Rapid urine-based screening for tuberculosis in HIV-positive patients admitted to hospital in Africa (STAMP): a pragmatic, multicentre, parallel-group, double-blind, randomised controlled trial

Incidence of HIV-positive admission and inpatient mortality in Malawi (2012-2019)

OBJECTIVE

To investigate trends in population incidence of HIV-positive hospital admission and risk of in-hospital death among adults living with HIV between 2012 and 2019 in Blantyre, Malawi.

DESIGN

Population cohort study using an existing electronic health information system ('SPINE') at Queen Elizabeth Central Hospital and Blantyre census data.

METHODS

We used multiple imputation and negative binomial regression to estimate population age-specific and sex-specific admission rates over time. We used a log-binomial model to investigate trends in risk of in-hospital death.

RESULTS

Of 32 814 adult medical admissions during Q4 2012--Q3 2019, HIV status was recorded for 75.6%. HIV-positive admissions decreased substantially between 2012 and 2019. After imputation for missing data, HIV-positive admissions were highest in Q3 2013 (173 per 100 000 adult Blantyre residents) and lowest in Q3 2019 (53 per 100 000 residents). An estimated 10 818 fewer than expected people with HIV (PWH) [95% confidence interval (CI) 10 068-11 568] were admitted during 2012-2019 compared with the counterfactual situation where admission rates stayed the same throughout this period. Absolute reductions were greatest for women aged 25-34 years (2264 fewer HIV-positive admissions, 95% CI 2002-2526). In-hospital mortality for PWH was 23.5%, with no significant change over time in any age-sex group, and no association with antiretroviral therapy (ART) use at admission.

CONCLUSION

Rates of admission for adult PWH decreased substantially, likely because of large increases in community provision of HIV diagnosis, treatment and care. However, HIV-positive in-hospital deaths remain unacceptably high, despite improvements in ART coverage. A concerted research and implementation agenda is urgently needed to reduce inpatient deaths among PWH.

Does tuberculosis screening improve individual outcomes? A systematic review

BACKGROUND

To determine if tuberculosis (TB) screening improves patient outcomes, we conducted two systematic reviews to investigate the effect of TB screening on diagnosis, treatment outcomes, deaths (clinical review assessing 23 outcome indicators); and patient costs (economic review).

METHODS

Pubmed, EMBASE, Scopus and the Cochrane Library were searched between 1/1/1980-13/4/2020 (clinical review) and 1/1/2010-14/8/2020 (economic review). As studies were heterogeneous, data synthesis was narrative.

FINDINGS

Clinical review: of 27,270 articles, 18 (n=3 trials) were eligible. Nine involved general populations. Compared to passive case finding (PCF), studies showed lower smear grade (n=2/3) and time to diagnosis (n=2/3); higher pre-treatment losses to follow-up (screened 23% and 29% vs PCF 15% and 14%; n=2/2); and similar treatment success (range 68-81%; n=4) and case fatality (range 3-11%; n=5) in the screened group. Nine reported on risk groups. Compared to PCF, studies showed lower smear positivity among those culture-confirmed (n=3/4) and time to diagnosis (n=2/2); and similar (range 80-90%; n=2/2) treatment success in the screened group. Case fatality was lower in n=2/3 observational studies; both reported on established screening programmes. A neonatal trial and post-hoc analysis of a household contacts trial found screening was associated with lower all-cause mortality. Economic review: From 2841 articles, six observational studies were eligible. Total costs (n=6) and catastrophic cost prevalence (n=4; range screened 9-45% vs PCF 12-61%) was lower among those screened.

INTERPRETATION

We found very limited patient outcome data. Collecting and reporting this data must be prioritised to inform policy and practice.

FUNDING

WHO and EDCTP.

Constructing confidence: User perspectives on AlereLAM testing for tuberculosis

BACKGROUND

Diagnosing tuberculosis (TB) in people living with HIV (PLHIV) is challenging due to atypical clinical and radiological presentation and higher rates of sputum-negative or extrapulmonary disease. Urine LAM is a promising diagnostic biomarker to address these challenges. Yet, AlereLAM, a World Health Organization-recommended point-of-care (POC) test of this kind, remains underutilized. This study aimed to understand perspectives and experiences of those using AlereLAM.

METHODS

Fifteen semi-structured interviews were conducted with clinicians, nurses, program officers, laboratory staff, and patient advocates in Uganda, Kenya, and South Africa. Discussed topics included the approach to diagnosing TB, and experiences, perspectives, and country policy of AlereLAM testing.

RESULTS

The POC-friendly characteristics of AlereLAM require more work to be realized. Although limited by relatively low sensitivity and specificity, AlereLAM has important value for identifying TB in people with advanced HIV disease, especially when the environment enables constructing confidence in the test. The initial communication about the low performance by global agencies, restrictive eligibility criteria, reliance on CD4+ testing, and lack of advocacy and awareness were noted as reasons for its slow uptake.

CONCLUSION

The work of operationalizing diagnostics, including constructing confidence, is important to consider for policymakers, implementers, and funders when assessing acceptability, feasibility, and scale-up of a diagnostic.

Impact of diagnostic strategies for tuberculosis using lateral flow urine lipoarabinomannan assay in people living with HIV

BACKGROUND

Tuberculosis is the primary cause of hospital admission in people living with HIV, and the likelihood of death in the hospital is unacceptably high. The Alere Determine TB LAM Ag test (AlereLAM) is a point-of-care test and the only lateral flow lipoarabinomannan assay (LF-LAM) assay currently commercially available and recommended by the World Health Organization (WHO). A 2019 Cochrane Review summarised the diagnostic accuracy of LF-LAM for tuberculosis in people living with HIV. This systematic review assesses the impact of the use of LF-LAM (AlereLAM) on mortality and other patient-important outcomes.

OBJECTIVES

To assess the impact of the use of LF-LAM (AlereLAM) on mortality in adults living with HIV in inpatient and outpatient settings. To assess the impact of the use of LF-LAM (AlereLAM) on other patient-important outcomes in adults living with HIV, including time to diagnosis of tuberculosis, and time to initiation of tuberculosis treatment.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE (PubMed); Embase (Ovid); Science Citation Index Expanded (Web of Science), BIOSIS Previews, Scopus, LILACS; ProQuest Dissertations and Theses; ClinicalTrials.gov; and the WHO ICTRP up to 12 March 2021.

SELECTION CRITERIA

Randomized controlled trials that compared a diagnostic intervention including LF-LAM with diagnostic strategies that used smear microscopy, mycobacterial culture, a nucleic acid amplification test such as Xpert MTB/RIF, or a combination of these tests. We included adults (≥ 15 years) living with HIV.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for eligibility, extracted data, and analysed risk of bias using the Cochrane tool for assessing risk of bias in randomized studies. We contacted study authors for clarification as needed. We used risk ratio (RR) with 95% confidence intervals (CI). We used a fixed-effect model except in the presence of clinical or statistical heterogeneity, in which case we used a random-effects model. We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included three trials, two in inpatient settings and one in outpatient settings. All trials were conducted in sub-Saharan Africa and assessed the impact of diagnostic strategies that included LF-LAM on mortality when the test was used in conjunction with other tuberculosis diagnostic tests or clinical assessment for clinical decision-making in adults living with HIV. Inpatient settings  In inpatient settings, the use of LF-LAM testing as part of a tuberculosis diagnostic strategy likely reduces mortality in people living with HIV at eight weeks compared to routine tuberculosis diagnostic testing without LF-LAM (pooled RR 0.85, 95% CI 0.76 to 0.94; 5102 participants, 2 trials; moderate-certainty evidence). That is, people living with HIV who received LF-LAM had 15% lower risk of mortality. The absolute effect was 34 fewer deaths per 1000 (from 14 fewer to 55 fewer). In inpatient settings, the use of LF-LAM testing as part of a tuberculosis diagnostic strategy probably results in a slight increase in the proportion of people living with HIV who were started on tuberculosis treatment compared to routine tuberculosis diagnostic testing without LF-LAM (pooled RR 1.26, 95% CI 0.94 to 1.69; 5102 participants, 2 trials; moderate-certainty evidence).  Outpatient settings In outpatient settings, the use of LF-LAM testing as part of a tuberculosis diagnostic strategy may reduce mortality in people living with HIV at six months compared to routine tuberculosis diagnostic testing without LF-LAM (RR 0.89, 95% CI 0.71 to 1.11; 2972 participants, 1 trial; low-certainty evidence). Although this trial did not detect a difference in mortality, the direction of effect was towards a mortality reduction, and the effect size was similar to that in inpatient settings.  In outpatient settings, the use of LF-LAM testing as part of a tuberculosis diagnostic strategy may result in a large increase in the proportion of people living with HIV who were started on tuberculosis treatment compared to routine tuberculosis diagnostic testing without LF-LAM (RR 5.44, 95% CI 4.70 to 6.29, 3022 participants, 1 trial; low-certainty evidence). Other patient-important outcomes Assessment of other patient-important and implementation outcomes in the trials varied. The included trials demonstrated that a higher proportion of people living with HIV were able to produce urine compared to sputum for tuberculosis diagnostic testing; a higher proportion of people living with HIV were diagnosed with tuberculosis in the group that received LF-LAM; and the incremental diagnostic yield was higher for LF-LAM than for urine or sputum Xpert MTB/RIF.

AUTHORS' CONCLUSIONS

In inpatient settings, the use of LF-LAM as part of a tuberculosis diagnostic testing strategy likely reduces mortality and probably results in a slight increase in tuberculosis treatment initiation in people living with HIV. The reduction in mortality may be due to earlier diagnosis, which facilitates prompt treatment initiation. In outpatient settings, the use of LF-LAM testing as part of a tuberculosis diagnostic strategy may reduce mortality and may result in a large increase in tuberculosis treatment initiation in people living with HIV. Our results support the implementation of LF-LAM to be used in conjunction with other WHO-recommended tuberculosis diagnostic tests to assist in the rapid diagnosis of tuberculosis in people living with HIV.

New management approaches to tuberculosis in people living with HIV

PURPOSE OF REVIEW

People living with HIV (PLWH) are commonly coinfected with Mycobacterium tuberculosis, particularly in high-transmission resource-limited regions. Despite expanded access to antiretroviral therapy and tuberculosis (TB) treatment, TB remains the leading cause of death among PLWH. This review discusses recent advances in the management of TB in PLWH and examines emerging therapeutic approaches to improve outcomes of HIV-associated TB.

RECENT FINDINGS

Three recent key developments have transformed the management of HIV-associated TB. First, the scaling-up of rapid point-of-care urine-based tests for screening and diagnosis of TB in PLWH has facilitated early case detection and treatment. Second, increasing the availability of potent new and repurposed drugs to treat drug-resistant TB has generated optimism about the treatment and outcome of multidrug-resistant and extensively drug-resistant TB. Third, expanded access to the integrase inhibitor dolutegravir to treat HIV in resource-limited regions has simplified the management of TB/HIV coinfected patients and minimized serious adverse events.

SUMMARY

While it is unequivocal that substantial progress has been made in early detection and treatment of HIV-associated TB, significant therapeutic challenges persist. To optimize the management and outcomes of TB in HIV, therapeutic approaches that target the pathogen as well as enhance the host response should be explored.

A longitudinal observational study of aetiology and long-term outcomes of sepsis in Malawi revealing the key role of disseminated tuberculosis

Background

Sepsis protocols in sub-Saharan Africa are typically extrapolated from high-income settings, yet sepsis in sub-Saharan Africa is likely caused by distinct pathogens and may require novel treatment strategies. Data to guide such strategies are lacking. We aimed to define causes and modifiable factors associated with sepsis outcomes in Blantyre, Malawi, in order to inform the design of treatment strategies tailored to sub-Saharan Africa.

Methods

We recruited 225 adults who met a sepsis case definition defined by fever and organ dysfunction in an observational cohort study at a single tertiary center. Etiology was defined using culture, antigen detection, serology, and polymerase chain reaction. The effect of treatment on 28-day outcomes was assessed using Bayesian logistic regression.

Results

There were 143 of 213 (67%) participants living with human immunodeficiency virus (HIV). We identified a diagnosis in 145 of 225 (64%) participants, most commonly tuberculosis (TB; 34%) followed by invasive bacterial infections (17%), arboviral infections (13%), and malaria (9%). TB was associated with HIV infection, whereas malaria and arboviruses with the absence of HIV infection. Antituberculous chemotherapy was associated with survival (adjusted odds ratio for 28-day death, 0.17; 95% credible interval, 0.05–0.49 for receipt of antituberculous therapy). Of those with confirmed etiology, 83% received the broad-spectrum antibacterial ceftriaxone, but it would be expected to be active in only 24%.

Conclusions

Sepsis in Blantyre, Malawi, is caused by a range of pathogens; the majority are not susceptible to the broad-spectrum antibacterials that most patients receive. HIV status is a key determinant of etiology. Novel antimicrobial strategies for sepsis tailored to sub-Saharan Africa, including consideration of empiric antituberculous therapy in individuals living with HIV, should be developed and trialed.

Clofazimine for Treatment of Cryptosporidiosis in Human Immunodeficiency Virus Infected Adults: An Experimental Medicine, Randomized, Double-blind, Placebo-controlled Phase 2a Trial

Background

We evaluated the efficacy, pharmacokinetics (PK), and safety of clofazimine (CFZ) in patients living with human immunodeficiency virus (HIV) with cryptosporidiosis.

Methods

We performed a randomized, double-blind, placebo-controlled study. Primary outcomes in part A were reduction in Cryptosporidium shedding, safety, and PK. Primary analysis was according to protocol (ATP). Part B of the study compared CFZ PK in matched individuals living with HIV without cryptosporidiosis.

Results

Twenty part A and 10 part B participants completed the study ATP. Almost all part A participants had high viral loads and low CD4 counts, consistent with failure of antiretroviral (ARV) therapy. At study entry, the part A CFZ group had higher Cryptosporidium shedding, total stool weight, and more diarrheal episodes compared with the placebo group. Over the inpatient period, compared with those who received placebo, the CFZ group Cryptosporidium shedding increased by 2.17 log2 Cryptosporidium per gram stool (95% upper confidence limit, 3.82), total stool weight decreased by 45.3 g (P = .37), and number of diarrheal episodes increased by 2.32 (P = .87). The most frequent solicited adverse effects were diarrhea, abdominal pain, and malaise. One placebo and 3 CFZ participants died during the study. Plasma levels of CFZ in participants with cryptosporidiosis were 2-fold lower than in part B controls.

Conclusions

Our findings do not support the efficacy of CFZ for the treatment of cryptosporidiosis in a severely immunocompromised HIV population. However, this trial demonstrates a pathway to assess the therapeutic potential of drugs for cryptosporidiosis treatment. Screening persons living with HIV for diarrhea, and especially Cryptosporidium infection, may identify those failing ARV therapy.

Clinical Trials Registration

NCT03341767.

Clinical, radiological, and laboratory predictors of a positive urine lipoarabinomannan test in sputum-scarce and sputum-negative patients with HIV-associated tuberculosis in two Johannesburg hospitals

Background

Tuberculosis (TB) is a major cause of mortality in persons living with HIV (PLWH). Sputum-based diagnosis of TB in patients with low CD4 counts is hampered by paucibacillary disease and consequent sputum scarcity or negative sputum results. Urine lipoarabinomannan (LAM) has shown promise in the point-of-care detection of TB in this patient subset but lacks sensitivity, and its exact role in a diagnostic algorithm for TB in South Africa remains to be clarified.

Objectives

The objective of this study was to better define the patient profile and the TB characteristics associated with a positive urine LAM (LAM+ve) test.

Method

This multicentre retrospective record review examined the clinical, radiological, and laboratory characteristics of hospitalised PLWH receiving urine LAM testing with sputum-scarce and/or negative sputum GeneXpert ^® (mycobacterium tuberculosis/resistance to rifampicin [MTB/RIF]) results.

Results

More than a third of patients, 121/342 (35%), were LAM+ve. The positive yield was greater in the sputum-scarce than the sputum-negative group, 66/156 (42%) versus 55/186 (30%), P = 0.0141, respectively. Patients who were LAM+ve were more likely to be confused (odds ratio [OR] = 2.2, 95% confidence interval [CI] = 1.2–3.7, P = 0.0045), have a higher median heart rate (P = 0.0135) and an elevated quick sepsis-related organ failure assessment score (≥ 2), OR = 3.5, 95% CI = 1.6–7.6, P = 0.0014. A LAM+ve test was significantly associated with disseminated TB (dTB), P < 0.0001, TB-related immune reconstitution inflammatory syndrome (IRIS), P = 0.0035, and abdominal TB, P < 0.0001. Laboratory predictors of a LAM+ve status included renal dysfunction, P = 0.044, severe anaemia, P = 0.0116, and an elevated C-reactive protein, P = 0.0131. Of the 12 PLWH with disseminated non-TB mycobacteria cultured from the blood and/or bone marrow, n = 9 (75%) had a LAM+ve result (OR = 5.8, 95% CI = 1.6–20.8, P = 0.0053).

Conclusion

Urine LAM testing of hospitalised PLWH with suspected active TB had significant diagnostic utility in those that were sputum-scarce or sputum-negative. A LAM+ve result was associated with dTB, clinical and laboratory markers of severe illness, and TB-IRIS. Disseminated non-tuberculous mycobacterial infection of hospitalised PLWH may also yield urine LAM+ve results, and mycobacterial cultures must be checked in those non-responsive to conventional TB treatment. Selective use of the LAM test in the critically ill is likely to maximise the diagnostic yield, improve the test’s predictive value, and reduce the time to TB diagnosis and initiation of treatment.

Early Empirical Tuberculosis Treatment in HIV-Positive Patients Admitted to Hospital in South Africa: An Observational Cohort Study

BACKGROUND

Empirical tuberculosis (TB) treatment in human immunodeficiency virus (HIV)-positive inpatients is common and may undermine the impact of new diagnostics. We sought to describe empirical TB treatment and compare characteristics and outcomes with patients treated for TB after screening.

METHODS

This was a retrospective observational cohort study of HIV-positive inpatients treated empirically for TB prior to TB screening. Data on clinical characteristics, investigations, and outcomes were collected from medical records. Comparison cohorts with microbiologically confirmed or empirical TB treatment after TB screening with Xpert MTB/RIF and urine lipoarabinomannan assays were taken from South African Screening for Tuberculosis to Reduce AIDS-Related Mortality in Hospitalized Patients in Africa (STAMP) trial site. In-hospital mortality was compared using a competing-risks analysis adjusted for age, sex, and CD4 cell count.

RESULTS

Between January 2016 and September 2017, 100 patients excluded from STAMP were treated for TB empirically prior to TB screening. After enrollment in STAMP and TB screening, 240 of 1177 (20.4%) patients received TB treatment, of whom 123 had positive TB tests and 117 were treated empirically. Characteristics were similar among early empirically treated patients and those treated after TB screening. 50% of early empirical TB treatment was based on radiological investigations, 22% on cerebrospinal or pleural fluid testing, and 28% on clinical features alone. Only 11 of 100 empirically treated patients had subsequent microbiological confirmation. In-hospital mortality was lower in patients with microbiologically confirmed TB compared to those treated empirically (adjusted subdistribution hazard ratio, 0.5 [95% confidence interval, .3-.9).

CONCLUSIONS

Empirical TB treatment remains common in severely ill HIV-positive inpatients. These patients may benefit from TB screening using existing rapid diagnostics, both to improve confirmation of TB disease and reduce overtreatment for TB.

Plasma hemoglobin and the risk of death in HIV/AIDS patients treated with antiretroviral therapy

Background: Previous studies concerning the effect of plasma hemoglobin (HB) and other factors that may modify the risk of death in people living with HIV/AIDS (PLHIV) treated with antiretroviral therapy (ART) are limited.

Results: Higher HB was independently linked to a lower death risk in PLHIV, with a decrease of 29% (13%, 43%) per standard deviation (SD) increment after adjusting for CD4, VL and other potential factors [hazard ratio (HR): 0.71, 95% confidence interval (CI): 0.57-0.87, P<0.001]. In addition, the addition of HB to the predictive model containing VL and CD4 significantly improved the C-index, by 0.69% (95% CI: 0.68%-0.71%), and net discrimination, by 0.5% (95% CI: 0.0%-1.6%, P=0.040), when predicting the death risk of PLHIV.

Conclusions: A lower level of HB was an independent risk factor for HIV/AIDS-associated death in PLHIV. HB combined with VL and CD4 may be an appropriate predictive model of the death risk of PLHIV.

Materials and methods: A propensity-score matching (PSM) approach was applied to select a total of 750 PLHIV (150 deceased and 600 living) from the AIDS prevention and control information system in the Wenzhou area from 2006 to 2018. Multivariable Cox proportional hazards regression models were formulated to estimate the effect of HB. The predictive performance improvement contributed by HB was evaluated using the C-index and net reclassification improvement.

Accuracy of a Novel Urine Test, Fujifilm SILVAMP Tuberculosis Lipoarabinomannan, for the Diagnosis of Pulmonary Tuberculosis in Children

BACKGROUND

An accurate point-of-care test for tuberculosis (TB) in children remains an elusive goal. Recent evaluation of a novel point-of-care urinary lipoarabinomannan test, Fujifilm SILVAMP Tuberculosis Lipoarabinomannan (FujiLAM), in adults living with human immunodeficiency virus (HIV) showed significantly superior sensitivity than the current Alere Determine Tuberculosis Lipoarabinomannan test (AlereLAM). We therefore compared the accuracy of FujiLAM and AlereLAM in children with suspected TB.

METHODS

Children hospitalized with suspected TB in Cape Town, South Africa, were enrolled (consecutive admissions plus enrichment for a group of children living with HIV and with TB), their urine was collected and biobanked, and their sputum was tested with mycobacterial culture and Xpert MTB/RIF or Xpert MTB/RIF Ultra. Biobanked urine was subsequently batch tested with FujiLAM and AlereLAM. Children were categorized as having microbiologically confirmed TB, unconfirmed TB (clinically diagnosed), or unlikely TB.

RESULTS

A total of 204 children were enrolled and had valid results from both index tests, as well as sputum microbiological testing. Compared to a microbiological reference standard, the sensitivity of FujiLAM and AlereLAM was similar (42% and 50%, respectively), but lower than that of Xpert MTB/RIF of sputum (74%). The sensitivity of FujiLAM was higher in children living with HIV (60%) and malnourished children (62%). The specificity of FujiLAM was substantially higher than that of AlereLAM (92% vs 66%, respectively). The specificity of both tests was higher in children 2 years or older (FujiLAM, 96%; AlereLAM, 72%).

CONCLUSIONS

The high specificity of FujiLAM suggests utility as a "rule-in" test for children with a high pretest probability of TB, including hospitalized children living with HIV or with malnutrition.

"SILVAMP TB LAM" Rapid Urine Tuberculosis Test Predicts Mortality in Patients Hospitalized With Human Immunodeficiency Virus in South Africa

Reducing diagnostic delay is key toward decreasing tuberculosis-associated deaths in people living with human immunodeficiency virus. In tuberculosis patients with retrospective urine testing, the point-of-care Fujifilm SILVAMP TB LAM (FujiLAM) could have rapidly diagnosed tuberculosis in up to 89% who died. In FujiLAM negative patients, the probability of 12-week survival was 86–97%.

Reduction in Baseline CD4 Count Testing Following Human Immunodeficiency Virus "Treat All" Adoption in Uganda

Baseline CD4 testing rates declined from 73% to 21% between 2013 and 2018 with adoption of "Treat All" in Uganda. Advanced human immunodeficiency virus (HIV) disease (CD4 count < 200 cells/µL) remained common (24% of those tested in 2018, 83% of whom had World Health Organization stage I/II disease). Despite frequent presentation with advanced HIV disease, CD4 testing has declined dramatically.

Urine lipoarabinomannan for rapid tuberculosis diagnosis in HIV-infected adult outpatients in Khayelitsha

Background

Decreasing tuberculosis (TB) mortality is constrained by diagnostic and treatment delays. The World Health Organization (WHO) recently actively recommended the point-of-care Alere Determine Lipoarabinomannan Ag assay (AlereLAM) to assist in the diagnosis of tuberculosis in specific HIV-infected outpatients.

Objectives

The primary objective of this study was to compare time to ambulatory TB treatment in HIV-infected adults with CD4 ≤ 100 cells/μL before and after (‘primary comparison groups’) availability of AlereLAM. In pre-specified subgroups, we prospectively assessed AlereLAM-positive prevalence.

Method

Clinicians prospectively performed AlereLAM in HIV-infected adults with TB symptoms and either CD4 ≤ 100 cells/μL or ‘seriously ill’ criteria. In a retrospective arm of equal duration, clinicians retrospectively collected data on HIV-infected adults with CD4 ≤ 100 cells/μL who initiated TB treatment.

Results

A total of 115 prospectively eligible adults (of whom 55 had CD4 ≤ 100 cells/μL) and 77 retrospectively eligible patients were included. In the primary comparison groups, the retrospective and prospective arms had similar age and sex distribution. With availability of AlereLAM, the time to TB treatment decreased from a median of 4 to 3 days (p = 0.0557). With availability of AlereLAM, same-day TB treatment initiation rose from 9.1% to 32.7% (p = 0.0006). In those with CD4 ≤ 100 only, those with ‘seriously ill’ criteria only, and in those meeting either, or both, of these criteria, AlereLAM was positive in 10.5%, 21.9%, 34.8% and 48.4% respectively.

Conclusion

Availability of AlereLAM led to more patients initiating same-day TB treatment. Using both CD4 ≤ 100 and ‘seriously ill’ criteria gave the greatest yield. Results of this study have informed local policy design.

Turning threats into opportunities: how to implement and advance quality TB services for people with HIV during the COVID-19 pandemic and beyond

INTRODUCTION

Until COVID-19, tuberculosis (TB) was the leading infectious disease killer globally, disproportionally affecting people with HIV. The COVID-19 pandemic is threatening the gains made in the fight against both diseases.

DISCUSSION

Although crucial guidance has been released on how to maintain TB and HIV services during the pandemic, it is acknowledged that what was considered normal service pre-pandemic needs to improve to ensure that we rebuild person-centred, inclusive and quality healthcare services. The threat that the pandemic may reverse gains in the response to TB and HIV may be turned into an opportunity by pivoting to using proven differentiated service delivery approaches and innovative technologies that can be used to maintain care during the pandemic and accelerate improved service delivery in the long term. Models of care should be convenient, supportive and sufficiently differentiated to avoid burdensome clinic visits for medication pick-ups or directly observed treatments. Additionally, the pandemic has highlighted the chronic and short-sighted lack of investment in health systems and the need to prioritize research and development to close the gaps in TB diagnosis, treatment and prevention, especially for children and people with HIV. Most importantly, TB-affected communities and civil society must be supported to lead the planning, implementation and monitoring of TB and HIV services, especially in the time of COVID-19 where services have been disrupted, and to report on legal, policy and gender-related barriers to access experienced by affected people. This will help to ensure that TB services are held accountable by affected communities for delivering equitable access to quality, affordable and non-discriminatory services during and beyond the pandemic.

CONCLUSIONS

Successfully reaching the related targets of ending TB and AIDS as public health threats by 2030 requires rebuilding of stronger, more inclusive health systems by advancing equitable access to quality TB services, including for people with HIV, both during and after the COVID-19 pandemic. Moreover, services must be rights-based, community-led and community-based, to ensure that no one is left behind.

Xpert MTB/RIF and Xpert Ultra assays for screening for pulmonary tuberculosis and rifampicin resistance in adults, irrespective of signs or symptoms

BACKGROUND

Tuberculosis is a leading cause of infectious disease-related death and is one of the top 10 causes of death worldwide. The World Health Organization (WHO) recommends the use of specific rapid molecular tests, including Xpert MTB/RIF or Xpert Ultra, as initial diagnostic tests for the detection of tuberculosis and rifampicin resistance in people with signs and symptoms of tuberculosis. However, the WHO estimates that nearly one-third of all active tuberculosis cases go undiagnosed and unreported. We were interested in whether a single test, Xpert MTB/RIF or Xpert Ultra, could be useful as a screening test to close this diagnostic gap and improve tuberculosis case detection.

OBJECTIVES

To estimate the accuracy of Xpert MTB/RIF and Xpert Ultra for screening for pulmonary tuberculosis in adults, irrespective of signs or symptoms of pulmonary tuberculosis in high-risk groups and in the general population. Screening "irrespective of signs or symptoms" refers to screening of people who have not been assessed for the presence of tuberculosis symptoms (e.g. cough). To estimate the accuracy of Xpert MTB/RIF and Xpert Ultra for detecting rifampicin resistance in adults screened for tuberculosis, irrespective of signs and symptoms of pulmonary tuberculosis in high-risk groups and in the general population.

SEARCH METHODS

We searched 12 databases including the Cochrane Infectious Diseases Group Specialized Register, MEDLINE and Embase, on 19 March 2020 without language restrictions. We also reviewed reference lists of included articles and related Cochrane Reviews, and contacted researchers in the field to identify additional studies.

SELECTION CRITERIA

Cross-sectional and cohort studies in which adults (15 years and older) in high-risk groups (e.g. people living with HIV, household contacts of people with tuberculosis) or in the general population were screened for pulmonary tuberculosis using Xpert MTB/RIF or Xpert Ultra. For tuberculosis detection, the reference standard was culture. For rifampicin resistance detection, the reference standards were culture-based drug susceptibility testing and line probe assays.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data using a standardized form and assessed risk of bias and applicability using QUADAS-2. We used a bivariate random-effects model to estimate pooled sensitivity and specificity with 95% credible intervals (CrIs) separately for tuberculosis detection and rifampicin resistance detection. We estimated all models using a Bayesian approach. For tuberculosis detection, we first estimated screening accuracy in distinct high-risk groups, including people living with HIV, household contacts, people residing in prisons, and miners, and then in several high-risk groups combined.

MAIN RESULTS

We included a total of 21 studies: 18 studies (13,114 participants) evaluated Xpert MTB/RIF as a screening test for pulmonary tuberculosis and one study (571 participants) evaluated both Xpert MTB/RIF and Xpert Ultra. Three studies (159 participants) evaluated Xpert MTB/RIF for rifampicin resistance. Fifteen studies (75%) were conducted in high tuberculosis burden and 16 (80%) in high TB/HIV-burden countries. We judged most studies to have low risk of bias in all four QUADAS-2 domains and low concern for applicability. Xpert MTB/RIF and Xpert Ultra as screening tests for pulmonary tuberculosis In people living with HIV (12 studies), Xpert MTB/RIF pooled sensitivity and specificity (95% CrI) were 61.8% (53.6 to 69.9) (602 participants; moderate-certainty evidence) and 98.8% (98.0 to 99.4) (4173 participants; high-certainty evidence). Of 1000 people where 50 have tuberculosis on culture, 40 would be Xpert MTB/RIF-positive; of these, 9 (22%) would not have tuberculosis (false-positives); and 960 would be Xpert MTB/RIF-negative; of these, 19 (2%) would have tuberculosis (false-negatives). In people living with HIV (1 study), Xpert Ultra sensitivity and specificity (95% CI) were 69% (57 to 80) (68 participants; very low-certainty evidence) and 98% (97 to 99) (503 participants; moderate-certainty evidence). Of 1000 people where 50 have tuberculosis on culture, 53 would be Xpert Ultra-positive; of these, 19 (36%) would not have tuberculosis (false-positives); and 947 would be Xpert Ultra-negative; of these, 16 (2%) would have tuberculosis (false-negatives). In non-hospitalized people in high-risk groups (5 studies), Xpert MTB/RIF pooled sensitivity and specificity were 69.4% (47.7 to 86.2) (337 participants, low-certainty evidence) and 98.8% (97.2 to 99.5) (8619 participants, moderate-certainty evidence). Of 1000 people where 10 have tuberculosis on culture, 19 would be Xpert MTB/RIF-positive; of these, 12 (63%) would not have tuberculosis (false-positives); and 981 would be Xpert MTB/RIF-negative; of these, 3 (0%) would have tuberculosis (false-negatives). We did not identify any studies using Xpert MTB/RIF or Xpert Ultra for screening in the general population. Xpert MTB/RIF as a screening test for rifampicin resistance Xpert MTB/RIF sensitivity was 81% and 100% (2 studies, 20 participants; very low-certainty evidence), and specificity was 94% to 100%, (3 studies, 139 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Of the high-risks groups evaluated, Xpert MTB/RIF applied as a screening test was accurate for tuberculosis in high tuberculosis burden settings. Sensitivity and specificity were similar in people living with HIV and non-hospitalized people in high-risk groups. In people living with HIV, Xpert Ultra sensitivity was slightly higher than that of Xpert MTB/RIF and specificity similar. As there was only one study of Xpert Ultra in this analysis, results should be interpreted with caution. There were no studies that evaluated the tests in people with diabetes mellitus and other groups considered at high-risk for tuberculosis, or in the general population.

The utility of point-of-care urinary lipoarabinomannan testing for the diagnosis of tuberculosis in critically ill patients: a prospective observational study

Background

Tuberculosis is a major global public health concern. Patients with tuberculosis who require critical care have a high mortality and delay in initiating antituberculous therapy is associated with increased mortality. Lipoarabinomannan (LAM) is a lipopolysaccharide found in the cell wall of Mycobacterium tuberculosis. Urinary LAM may be used as a bedside diagnostic test for tuberculosis.

Methods

The study was a single centre, prospective observational study that compared the utility of urinary LAM with conventional tuberculosis diagnostic modalities in patients with suspected tuberculosis who required intensive care admission. Urinary LAM testing was performed using the Alere Determine TB LAM Ag lateral flow assay test strips. A patient was classified as having confirmed tuberculosis if they met the following criteria: a clinical presentation compatible with tuberculosis, with either a positive TB culture, a positive GeneXpert, or a histological diagnosis of tuberculosis.

Results

Fifty patients were included in the study, with 12 having confirmed tuberculosis. All patients received mechanical ventilation, and the ICU mortality was 60%. Urinary LAM had a sensitivity of 50.0% (95% CI, 21.1 to 78.9%) and a specificity of 84.2% (95% CI, 68.8 to 94.0%) for confirmed tuberculosis.

Conclusion

Urinary LAM allows for rapid bedside diagnosis of tuberculosis in critically ill patients. A positive urinary LAM should prompt consideration to initiate antituberculous treatment while the results of further diagnostic testing are awaited.

What pulmonologists need to know about extrapulmonary tuberculosis

Extrapulmonary tuberculosis (EPT) can affect all organs. Its diagnosis is often challenging, especially when the lung is not involved. Some EPT locations, such as when the central nervous system is involved, are a medical emergency, and some have implications for treatment options and length. This review describes clinical features of EPT, diagnostic tests and treatment regimens.

Extrapulmonary tuberculosis can affect any organ, can be potentially life threatening or disabling, poses diagnostic difficulties and may change the type and length of treatment. Looking for concomitant pulmonary tuberculosis is essential.https://bit.ly/2YEaRVb

Xpert Ultra versus Xpert MTB/RIF for pulmonary tuberculosis and rifampicin resistance in adults with presumptive pulmonary tuberculosis

BACKGROUND

Xpert MTB/RIF and Xpert MTB/RIF Ultra (Xpert Ultra) are World Health Organization (WHO)-recommended rapid tests that simultaneously detect tuberculosis and rifampicin resistance in people with signs and symptoms of tuberculosis. This review builds on our recent extensive Cochrane Review of Xpert MTB/RIF accuracy.

OBJECTIVES

To compare the diagnostic accuracy of Xpert Ultra and Xpert MTB/RIF for the detection of pulmonary tuberculosis and detection of rifampicin resistance in adults with presumptive pulmonary tuberculosis. For pulmonary tuberculosis and rifampicin resistance, we also investigated potential sources of heterogeneity. We also summarized the frequency of Xpert Ultra trace-positive results, and estimated the accuracy of Xpert Ultra after repeat testing in those with trace-positive results.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, LILACS, Scopus, the WHO ICTRP, the ISRCTN registry, and ProQuest to 28 January 2020 with no language restriction.

SELECTION CRITERIA

We included diagnostic accuracy studies using respiratory specimens in adults with presumptive pulmonary tuberculosis that directly compared the index tests. For pulmonary tuberculosis detection, the reference standards were culture and a composite reference standard. For rifampicin resistance, the reference standards were culture-based drug susceptibility testing and line probe assays.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data using a standardized form, including data by smear and HIV status. We assessed risk of bias using QUADAS-2 and QUADAS-C. We performed meta-analyses comparing pooled sensitivities and specificities, separately for pulmonary tuberculosis detection and rifampicin resistance detection, and separately by reference standard. Most analyses used a bivariate random-effects model. For tuberculosis detection, we estimated accuracy in studies in participants who were not selected based on prior microscopy testing or history of tuberculosis. We performed subgroup analyses by smear status, HIV status, and history of tuberculosis. We summarized Xpert Ultra trace results.

MAIN RESULTS

We identified nine studies (3500 participants): seven had unselected participants (2834 participants). All compared Xpert Ultra and Xpert MTB/RIF for pulmonary tuberculosis detection; seven studies used a paired comparative accuracy design, and two studies used a randomized design. Five studies compared Xpert Ultra and Xpert MTB/RIF for rifampicin resistance detection; four studies used a paired design, and one study used a randomized design. Of the nine included studies, seven (78%) were mainly or exclusively in high tuberculosis burden countries. For pulmonary tuberculosis detection, most studies had low risk of bias in all domains. Pulmonary tuberculosis detection Xpert Ultra pooled sensitivity and specificity (95% credible interval) against culture were 90.9% (86.2 to 94.7) and 95.6% (93.0 to 97.4) (7 studies, 2834 participants; high-certainty evidence) versus Xpert MTB/RIF pooled sensitivity and specificity of 84.7% (78.6 to 89.9) and 98.4% (97.0 to 99.3) (7 studies, 2835 participants; high-certainty evidence). The difference in the accuracy of Xpert Ultra minus Xpert MTB/RIF was estimated at 6.3% (0.1 to 12.8) for sensitivity and -2.7% (-5.7 to -0.5) for specificity. If the point estimates for Xpert Ultra and Xpert MTB/RIF are applied to a hypothetical cohort of 1000 patients, where 10% of those presenting with symptoms have pulmonary tuberculosis, Xpert Ultra will miss 9 cases, and Xpert MTB/RIF will miss 15 cases. The number of people wrongly diagnosed with pulmonary tuberculosis would be 40 with Xpert Ultra and 14 with Xpert MTB/RIF. In smear-negative, culture-positive participants, pooled sensitivity was 77.5% (67.6 to 85.6) for Xpert Ultra versus 60.6% (48.4 to 71.7) for Xpert MTB/RIF; pooled specificity was 95.8% (92.9 to 97.7) for Xpert Ultra versus 98.8% (97.7 to 99.5) for Xpert MTB/RIF (6 studies). In people living with HIV, pooled sensitivity was 87.6% (75.4 to 94.1) for Xpert Ultra versus 74.9% (58.7 to 86.2) for Xpert MTB/RIF; pooled specificity was 92.8% (82.3 to 97.0) for Xpert Ultra versus 99.7% (98.6 to 100.0) for Xpert MTB/RIF (3 studies). In participants with a history of tuberculosis, pooled sensitivity was 84.2% (72.5 to 91.7) for Xpert Ultra versus 81.8% (68.7 to 90.0) for Xpert MTB/RIF; pooled specificity was 88.2% (70.5 to 96.6) for Xpert Ultra versus 97.4% (91.7 to 99.5) for Xpert MTB/RIF (4 studies). The proportion of Ultra trace-positive results ranged from 3.0% to 30.4%. Data were insufficient to estimate the accuracy of Xpert Ultra repeat testing in individuals with initial trace-positive results. Rifampicin resistance detection Pooled sensitivity and specificity were 94.9% (88.9 to 97.9) and 99.1% (97.7 to 99.8) (5 studies, 921 participants; high-certainty evidence) for Xpert Ultra versus 95.3% (90.0 to 98.1) and 98.8% (97.2 to 99.6) (5 studies, 930 participants; high-certainty evidence) for Xpert MTB/RIF. The difference in the accuracy of Xpert Ultra minus Xpert MTB/RIF was estimated at -0.3% (-6.9 to 5.7) for sensitivity and 0.3% (-1.2 to 2.0) for specificity. If the point estimates for Xpert Ultra and Xpert MTB/RIF are applied to a hypothetical cohort of 1000 patients, where 10% of those presenting with symptoms have rifampicin resistance, Xpert Ultra will miss 5 cases, and Xpert MTB/RIF will miss 5 cases. The number of people wrongly diagnosed with rifampicin resistance would be 8 with Xpert Ultra and 11 with Xpert MTB/RIF. We identified a higher number of rifampicin resistance indeterminate results with Xpert Ultra, pooled proportion 7.6% (2.4 to 21.0) compared to Xpert MTB/RIF pooled proportion 0.8% (0.2 to 2.4). The estimated difference in the pooled proportion of indeterminate rifampicin resistance results for Xpert Ultra versus Xpert MTB/RIF was 6.7% (1.4 to 20.1).

AUTHORS' CONCLUSIONS

Xpert Ultra has higher sensitivity and lower specificity than Xpert MTB/RIF for pulmonary tuberculosis, especially in smear-negative participants and people living with HIV. Xpert Ultra specificity was lower than that of Xpert MTB/RIF in participants with a history of tuberculosis. The sensitivity and specificity trade-off would be expected to vary by setting. For detection of rifampicin resistance, Xpert Ultra and Xpert MTB/RIF had similar sensitivity and specificity. Ultra trace-positive results were common. Xpert Ultra and Xpert MTB/RIF provide accurate results and can allow rapid initiation of treatment for rifampicin-resistant and multidrug-resistant tuberculosis.

HIV-associated tuberculosis

Tuberculosis (TB) remains a leading cause of morbidity and mortality among people living with HIV. HIV-associated TB disproportionally affects African countries, particularly vulnerable groups at risk for both TB and HIV. Currently available TB diagnostics perform poorly in people living with HIV; however, new diagnostics such as Xpert Ultra and lateral flow urine lipoarabinomannan assays can greatly facilitate diagnosis of TB in people living with HIV. TB preventive treatment has been underutilized despite its proven benefits independent of antiretroviral therapy (ART). Shorter regimens using rifapentine can support increased availability and scale-up. Mortality is high in people with HIV-associated TB, and timely initiation of ART is critical. Programs should provide decentralized and integrated TB and HIV care in settings with high burden of both diseases to improve access to services that diagnose TB and HIV as early as possible. The new prevention and diagnosis tools recently recommended by WHO offer an immense opportunity to advance our fight against HIV-associated TB. They should be made widely available and scaled up rapidly supported by adequate funding with robust monitoring of the uptake to advance global TB elimination.

Xpert MTB/RIF Ultra and Xpert MTB/RIF assays for extrapulmonary tuberculosis and rifampicin resistance in adults

BACKGROUND

Xpert MTB/RIF Ultra (Xpert Ultra) and Xpert MTB/RIF are World Health Organization (WHO)-recommended rapid nucleic acid amplification tests (NAATs) widely used for simultaneous detection of Mycobacterium tuberculosis complex and rifampicin resistance in sputum. To extend our previous review on extrapulmonary tuberculosis (Kohli 2018), we performed this update to inform updated WHO policy (WHO Consolidated Guidelines (Module 3) 2020).

OBJECTIVES

To estimate diagnostic accuracy of Xpert Ultra and Xpert MTB/RIF for extrapulmonary tuberculosis and rifampicin resistance in adults with presumptive extrapulmonary tuberculosis.

SEARCH METHODS

Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, Web of Science, Latin American Caribbean Health Sciences Literature, Scopus, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, the International Standard Randomized Controlled Trial Number Registry, and ProQuest, 2 August 2019 and 28 January 2020 (Xpert Ultra studies), without language restriction.

SELECTION CRITERIA

Cross-sectional and cohort studies using non-respiratory specimens. Forms of extrapulmonary tuberculosis: tuberculous meningitis and pleural, lymph node, bone or joint, genitourinary, peritoneal, pericardial, disseminated tuberculosis. Reference standards were culture and a study-defined composite reference standard (tuberculosis detection); phenotypic drug susceptibility testing and line probe assays (rifampicin resistance detection).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and applicability using QUADAS-2. For tuberculosis detection, we performed separate analyses by specimen type and reference standard using the bivariate model to estimate pooled sensitivity and specificity with 95% credible intervals (CrIs). We applied a latent class meta-analysis model to three forms of extrapulmonary tuberculosis. We assessed certainty of evidence using GRADE.

MAIN RESULTS

69 studies: 67 evaluated Xpert MTB/RIF and 11 evaluated Xpert Ultra, of which nine evaluated both tests. Most studies were conducted in China, India, South Africa, and Uganda. Overall, risk of bias was low for patient selection, index test, and flow and timing domains, and low (49%) or unclear (43%) for the reference standard domain. Applicability for the patient selection domain was unclear for most studies because we were unsure of the clinical settings. Cerebrospinal fluid Xpert Ultra (6 studies) Xpert Ultra pooled sensitivity and specificity (95% CrI) against culture were 89.4% (79.1 to 95.6) (89 participants; low-certainty evidence) and 91.2% (83.2 to 95.7) (386 participants; moderate-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 168 would be Xpert Ultra-positive: of these, 79 (47%) would not have tuberculosis (false-positives) and 832 would be Xpert Ultra-negative: of these, 11 (1%) would have tuberculosis (false-negatives). Xpert MTB/RIF (30 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 71.1% (62.8 to 79.1) (571 participants; moderate-certainty evidence) and 96.9% (95.4 to 98.0) (2824 participants; high-certainty evidence). Of 1000 people where 100 have tuberculous meningitis, 99 would be Xpert MTB/RIF-positive: of these, 28 (28%) would not have tuberculosis; and 901 would be Xpert MTB/RIF-negative: of these, 29 (3%) would have tuberculosis. Pleural fluid Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity against culture were 75.0% (58.0 to 86.4) (158 participants; very low-certainty evidence) and 87.0% (63.1 to 97.9) (240 participants; very low-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 192 would be Xpert Ultra-positive: of these, 117 (61%) would not have tuberculosis; and 808 would be Xpert Ultra-negative: of these, 25 (3%) would have tuberculosis. Xpert MTB/RIF (25 studies) Xpert MTB/RIF pooled sensitivity and specificity against culture were 49.5% (39.8 to 59.9) (644 participants; low-certainty evidence) and 98.9% (97.6 to 99.7) (2421 participants; high-certainty evidence). Of 1000 people where 100 have pleural tuberculosis, 60 would be Xpert MTB/RIF-positive: of these, 10 (17%) would not have tuberculosis; and 940 would be Xpert MTB/RIF-negative: of these, 50 (5%) would have tuberculosis. Lymph node aspirate Xpert Ultra (1 study) Xpert Ultra sensitivity and specificity (95% confidence interval) against composite reference standard were 70% (51 to 85) (30 participants; very low-certainty evidence) and 100% (92 to 100) (43 participants; low-certainty evidence). Of 1000 people where 100 have lymph node tuberculosis, 70 would be Xpert Ultra-positive and 0 (0%) would not have tuberculosis; 930 would be Xpert Ultra-negative and 30 (3%) would have tuberculosis. Xpert MTB/RIF (4 studies) Xpert MTB/RIF pooled sensitivity and specificity against composite reference standard were 81.6% (61.9 to 93.3) (377 participants; low-certainty evidence) and 96.4% (91.3 to 98.6) (302 participants; low-certainty evidence). Of 1000 people where 100 have lymph node tuberculosis, 118 would be Xpert MTB/RIF-positive and 37 (31%) would not have tuberculosis; 882 would be Xpert MTB/RIF-negative and 19 (2%) would have tuberculosis. In lymph node aspirate, Xpert MTB/RIF pooled specificity against culture was 86.2% (78.0 to 92.3), lower than that against a composite reference standard. Using the latent class model, Xpert MTB/RIF pooled specificity was 99.5% (99.1 to 99.7), similar to that observed with a composite reference standard. Rifampicin resistance Xpert Ultra (4 studies) Xpert Ultra pooled sensitivity and specificity were 100.0% (95.1 to 100.0), (24 participants; low-certainty evidence) and 100.0% (99.0 to 100.0) (105 participants; moderate-certainty evidence). Of 1000 people where 100 have rifampicin resistance, 100 would be Xpert Ultra-positive (resistant): of these, zero (0%) would not have rifampicin resistance; and 900 would be Xpert Ultra-negative (susceptible): of these, zero (0%) would have rifampicin resistance. Xpert MTB/RIF (19 studies) Xpert MTB/RIF pooled sensitivity and specificity were 96.5% (91.9 to 98.8) (148 participants; high-certainty evidence) and 99.1% (98.0 to 99.7) (822 participants; high-certainty evidence). Of 1000 people where 100 have rifampicin resistance, 105 would be Xpert MTB/RIF-positive (resistant): of these, 8 (8%) would not have rifampicin resistance; and 895 would be Xpert MTB/RIF-negative (susceptible): of these, 3 (0.3%) would have rifampicin resistance.

AUTHORS' CONCLUSIONS

Xpert Ultra and Xpert MTB/RIF may be helpful in diagnosing extrapulmonary tuberculosis. Sensitivity varies across different extrapulmonary specimens: while for most specimens specificity is high, the tests rarely yield a positive result for people without tuberculosis. For tuberculous meningitis, Xpert Ultra had higher sensitivity and lower specificity than Xpert MTB/RIF against culture. Xpert Ultra and Xpert MTB/RIF had similar sensitivity and specificity for rifampicin resistance. Future research should acknowledge the concern associated with culture as a reference standard in paucibacillary specimens and consider ways to address this limitation.

Urine Lipoarabinomannan Testing for All HIV Patients Hospitalized in Medical Wards Identifies a Large Proportion of Patients With Tuberculosis at Risk of Death

Background

Diagnosing tuberculosis (TB), the leading cause of death in people with HIV, remains a challenge in resource-limited countries. We assessed TB diagnosis using a strategy that included systematic urine lipoarabinomannan (LAM) testing for all HIV patients hospitalized in medical wards and 6-month mortality according to LAM results.

Methods

This prospective, observational study included adult HIV patients hospitalized in the medical wards of a public district hospital in Malawi regardless of their TB symptoms or CD4 count. Each patient had a clinical examination, and Alere Determine TB-LAM, sputum microscopy, sputum GeneXpert MTB/RIF (Xpert), chest x-ray, and CD4 count were systematically requested.

Results

Among 387 inpatients, 54% had a CD4 <200 cells/µL, 64% had presumptive TB, and 90% had ≥1 TB symptom recorded in their medical file. LAM results were available for 99.0% of patients, microscopy for 62.8%, and Xpert for 60.7%. In total, 26.1% (100/383) had LAM-positive results, 48% (48/100) of which were grades 2-4. Any TB laboratory test result was positive in 30.8% (119/387). Among patients with no Xpert result, 28.5% (43/151) were LAM-positive. Cumulative 6-month mortality was 40.1% (151/377): 50.5% (49/97) in LAM-positives and 36.2% (100/276) in LAM-negatives (P = .013). In multivariable regression analyses, LAM-positive patients had a higher risk of mortality than LAM-negatives (adjusted odds ratio, 2.5; 95% CI, 1.1-5.8; P = .037).

Conclusions

In resource-limited hospital medical wards with high TB prevalence, a diagnostic strategy including systematic urine LAM testing for all HIV patients is an easily implementable strategy that identifies a large proportion of patients with TB at risk of death.

Tuberculosis in Hospitalized Patients With Human Immunodeficiency Virus: Clinical Characteristics, Mortality, and Implications From the Rapid Urine-based Screening for Tuberculosis to Reduce AIDS Related Mortality in Hospitalized Patients in Africa

BACKGROUND

Tuberculosis (TB) is the major killer of people living with human immunodeficiency virus (HIV) globally, with suboptimal diagnostics and management contributing to high case-fatality rates.

METHODS

A prospective cohort of patients with confirmed TB (Xpert MTB/RIF and/or Determine TB-LAM Ag positive) identified through screening HIV-positive inpatients with sputum and urine diagnostics in Malawi and South Africa (Rapid urine-based Screening for Tuberculosis to reduce AIDS Related Mortality in hospitalized Patients in Africa [STAMP] trial). Urine was tested prospectively (intervention) or retrospectively (standard of care arm). We defined baseline clinical phenotypes using hierarchical cluster analysis, and also used Cox regression analysis to identify associations with early mortality (≤56 days).

RESULTS

Of 322 patients with TB confirmed between October 2015 and September 2018, 78.0% had ≥1 positive urine test. Antiretroviral therapy (ART) coverage was 80.2% among those not newly diagnosed, but with median CD4 count 75 cells/µL and high HIV viral loads. Early mortality was 30.7% (99/322), despite near-universal prompt TB treatment. Older age, male sex, ART before admission, poor nutritional status, lower hemoglobin, and positive urine tests (TB-LAM and/or Xpert MTB/RIF) were associated with increased mortality in multivariate analyses. Cluster analysis (on baseline variables) defined 4 patient subgroups with early mortality ranging from 9.8% to 52.5%. Although unadjusted mortality was 9.3% lower in South Africa than Malawi, in adjusted models mortality was similar in both countries (hazard ratio, 0.9; P = .729).

CONCLUSIONS

Mortality following prompt inpatient diagnosis of HIV-associated TB remained unacceptably high, even in South Africa. Intensified management strategies are urgently needed, for which prognostic indicators could potentially guide both development and subsequent use.

The potential impact of urine-LAM diagnostics on tuberculosis incidence and mortality: A modelling analysis

BACKGROUND

Lateral flow urine lipoarabinomannan (LAM) tests could offer important new opportunities for the early detection of tuberculosis (TB). The currently licensed LAM test, Alere Determine TB LAM Ag ('LF-LAM'), performs best in the sickest people living with HIV (PLHIV). However, the technology continues to improve, with newer LAM tests, such as Fujifilm SILVAMP TB LAM ('SILVAMP-LAM') showing improved sensitivity, including amongst HIV-negative patients. It is important to anticipate the epidemiological impact that current and future LAM tests may have on TB incidence and mortality.

METHODS AND FINDINGS

Concentrating on South Africa, we examined the impact that widening LAM test eligibility would have on TB incidence and mortality. We developed a mathematical model of TB transmission to project the impact of LAM tests, distinguishing 'current' tests (with sensitivity consistent with LF-LAM), from hypothetical 'future' tests (having sensitivity consistent with SILVAMP-LAM). We modelled the impact of both tests, assuming full adoption of the 2019 WHO guidelines for the use of these tests amongst those receiving HIV care. We also simulated the hypothetical deployment of future LAM tests for all people presenting to care with TB symptoms, not restricted to PLHIV. Our model projects that 2,700,000 (95% credible interval [CrI] 2,000,000-3,600,000) and 420,000 (95% CrI 350,000-520,000) cumulative TB incident cases and deaths, respectively, would occur between 2020 and 2035 if the status quo is maintained. Relative to this comparator, current and future LAM tests would respectively avert 54 (95% CrI 33-86) and 90 (95% CrI 55-145) TB deaths amongst inpatients between 2020 and 2035, i.e., reductions of 5% (95% CrI 4%-6%) and 9% (95% CrI 7%-11%) in inpatient TB mortality. This impact in absolute deaths averted doubles if testing is expanded to include outpatients, yet remains <1% of country-level TB deaths. Similar patterns apply to incidence results. However, deploying a future LAM test for all people presenting to care with TB symptoms would avert 470,000 (95% CrI 220,000-870,000) incident TB cases (18% reduction, 95% CrI 9%-29%) and 120,000 (95% CrI 69,000-210,000) deaths (30% reduction, 95% CrI 18%-44%) between 2020 and 2035. Notably, this increase in impact arises largely from diagnosis of TB amongst those with HIV who are not yet in HIV care, and who would thus be ineligible for a LAM test under current guidelines. Qualitatively similar results apply under an alternative comparator assuming expanded use of GeneXpert MTB/RIF ('Xpert') for TB diagnosis. Sensitivity analysis demonstrates qualitatively similar results in a setting like Kenya, which also has a generalised HIV epidemic, but a lower burden of HIV/TB coinfection. Amongst limitations of this analysis, we do not address the cost or cost-effectiveness of future tests. Our model neglects drug resistance and focuses on the country-level epidemic, thus ignoring subnational variations in HIV and TB burden.

CONCLUSIONS

These results suggest that LAM tests could have an important effect in averting TB deaths amongst PLHIV with advanced disease. However, achieving population-level impact on the TB epidemic, even in high-HIV-burden settings, will require future LAM tests to have sufficient performance to be deployed more broadly than in HIV care.

Cost-effectiveness of a novel lipoarabinomannan test for tuberculosis in patients with HIV

Background

A novel urine lipoarabinomannan assay (FujiLAM) has higher sensitivity and higher cost than the first-generation AlereLAM assay. We evaluated the cost-effectiveness of FujiLAM for tuberculosis testing among hospitalized people with human immunodeficiency virus (HIV), irrespective of symptoms.

Methods

We used a microsimulation model to project clinical and economic outcomes of 3 testing strategies: (1) sputum Xpert MTB/RIF (Xpert), (2) sputum Xpert plus urine AlereLAM (Xpert+AlereLAM), (3) sputum Xpert plus urine FujiLAM (Xpert+FujiLAM). The modeled cohort matched that of a 2-country clinical trial. We applied diagnostic yields from a retrospective study (yields for Xpert/Xpert+AlereLAM/Xpert+FujiLAM among those with CD4 <200 cells/µL: 33%/62%/70%; among those with CD4 ≥200 cells/µL: 33%/35%/47%). Costs of Xpert/AlereLAM/FujiLAM were US$15/3/6 (South Africa) and $25/3/6 (Malawi). Xpert+FujiLAM was considered cost-effective if its incremental cost-effectiveness ratio (US$/year-of-life saved) was <$940 (South Africa) and <$750 (Malawi). We varied key parameters in sensitivity analysis and performed a budget impact analysis of implementing FujiLAM countrywide.

Results

Compared with Xpert+AlereLAM, Xpert+FujiLAM increased life expectancy by 0.2 years for those tested in South Africa and Malawi. Xpert+FujiLAM was cost-effective in both countries. Xpert+FujiLAM for all patients remained cost-effective compared with sequential testing and CD4-stratified testing strategies. FujiLAM use added 3.5% (South Africa) and 4.7% (Malawi) to 5-year healthcare costs of tested patients, primarily reflecting ongoing HIV treatment costs among survivors.

Conclusions

FujiLAM with Xpert for tuberculosis testing in hospitalized people with HIV is likely to increase life expectancy and be cost-effective at the currently anticipated price in South Africa and Malawi. Additional studies should evaluate FujiLAM in clinical practice settings.

Drug resistant Tuberculosis: A review

Tuberculosis (TB) was announced as a global emergency in 1993. There was an alarming counter attack of TB worldwide. However, when it was known that TB can be cured completely, the general public became ignorant towards the infection. The pathogenic organism Mycobacterium tuberculosis continuously evolved to resist the antagonist drugs. This has led to the outbreak of resistant strain that gave rise to "Multi Drug Resistant-Tuberculosis" and "Extensively Drug Resistant Tuberculosis" that can still be cured with a lower success rate. While the mechanism of resistance proceeds further, it ultimately causes unmanageable totally drug resistant TB (TDR-TB). Studying the molecular mechanisms underlying the resistance to drugs would help us grasp the genetics and pathophysiology of the disease. In this review, we present the molecular mechanisms behind Mycobacterium tolerance to drugs and their approach towards the development of multi-drug resistant, extremely drug resistant and totally drug resistant TB.

Diagnostic accuracy of 3 urine lipoarabinomannan tuberculosis assays in HIV-negative outpatients

BACKGROUNDInadequate tuberculosis (TB) diagnostics are a major hurdle in the reduction of disease burden, and accurate point-of-care tests (POCTs) are urgently needed. We assessed the diagnostic accuracy of Fujifilm SILVAMP TB lipoarabinomannan (FujiLAM) POCT for TB diagnosis in HIV-negative outpatients and compared it with Alere Determine TB LAM Ag (AlereLAM) POCT and a laboratory-based ultrasensitive electrochemiluminescence LAM research assay (EclLAM).METHODSIn this multicenter diagnostic test accuracy study, we recruited HIV-negative adults with symptoms suggestive of pulmonary TB presenting to outpatient health care centers in Peru and South Africa. Urine samples were tested using FujiLAM, AlereLAM, and EclLAM, and the diagnostic accuracy was assessed against a microbiological reference standard (MRS) and a composite reference standard.RESULTSThree hundred seventy-two HIV-negative participants were included and the prevalence of microbiologically confirmed TB was 30%. Compared with the MRS, the sensitivities of AlereLAM, FujiLAM, and EclLAM were 10.8% (95% confidence interval [CI] 6.3%-18.0%), 53.2% (95% CI 43.9%-62.1%), and 66.7% (95% CI 57.5%-74.7%), respectively. The specificities of AlereLAM, FujiLAM, and EclLAM were 92.3% (95% CI 88.5%-95.0%), 98.9% (95% CI 96.7%-99.6%), and 98.1% (95% CI 95.6%-99.2%), respectively. Positive likelihood ratios of AlereLAM, FujiLAM, and EclLAM were 1.4, 46.2, and 34.8, respectively, and positive predictive values were 37.5%, 95.2%, and 93.7%, respectively.CONCLUSIONCompared with AlereLAM, FujiLAM detected 5 times more patients with TB in HIV-negative participants, had a high positive predictive value, and has the potential to improve rapid diagnosis of TB at the point-of-care. EclLAM demonstrated that additional sensitivity gains are possible, which highlights LAM's potential as a biomarker. Additional research is required to assess FujiLAM's performance in prospective cohorts, its cost-effectiveness, and its impact in real-world clinical settings.FUNDINGGlobal Health Innovative Technology Fund, the UK Department for International Development, the Dutch Ministry of Foreign Affairs, the Bill and Melinda Gates Foundation, the Australian Department of Foreign Affairs and Trade, the German Federal Ministry of Education and Research through Kreditanstalt für Wiederaufbau, and the NIH and National Institute of Allergy and Infectious Diseases.

Advances in the diagnosis of pulmonary tuberculosis in children

Major challenges still exist in the accurate diagnosis of tuberculosis in children. Algorithms based on clinical and radiological features remain in widespread use despite poor performance. Newer molecular diagnostics allow for rapid identification of TB and detection of drug-resistance in a subset of children, but lack sensitivity. Molecular testing of multiple specimens, including non-traditional specimen types, such as nasopharyngeal aspirates and stool and urine, may improve sensitivity, but the optimal combination of specimens requires further research. Novel tests under development or evaluation include a urine lipoarabinomannan test with improved sensitivity and a range of biomarkers measured from stimulated or unstimulated peripheral blood.

Perspective for Precision Medicine for Tuberculosis

Tuberculosis is a bacterial infectious disease that is mainly transmitted from human to human via infectious aerosols. Currently, tuberculosis is the leading cause of death by an infectious disease world-wide. In the past decade, the number of patients affected by tuberculosis has increased by ~20 percent and the emergence of drug-resistant strains of Mycobacterium tuberculosis challenges the goal of elimination of tuberculosis in the near future. For the last 50 years, management of patients with tuberculosis has followed a standardized management approach. This standardization neglects the variation in human susceptibility to infection, immune response, the pharmacokinetics of drugs, and the individual duration of treatment needed to achieve relapse-free cure. Here we propose a package of precision medicine-guided therapies that has the prospect to drive clinical management decisions, based on both host immunity and M. tuberculosis strains genetics. Recently, important scientific discoveries and technological advances have been achieved that provide a perspective for individualized rather than standardized management of patients with tuberculosis. For the individual selection of best medicines and host-directed therapies, personalized drug dosing, and treatment durations, physicians treating patients with tuberculosis will be able to rely on these advances in systems biology and to apply them at the bedside.

Virological failure, HIV-1 drug resistance, and early mortality in adults admitted to hospital in Malawi: an observational cohort study

BACKGROUND

Antiretroviral therapy (ART) scale-up in sub-Saharan Africa combined with weak routine virological monitoring has driven increasing HIV drug resistance. We investigated ART failure, drug resistance, and early mortality among patients with HIV admitted to hospital in Malawi.

METHODS

This observational cohort study was nested within the rapid urine-based screening for tuberculosis to reduce AIDS-related mortality in hospitalised patients in Africa (STAMP) trial, which recruited unselected (ie, irrespective of clinical presentation) adult (aged ≥18 years) patients with HIV-1 at admission to medical wards. Patients were included in our observational cohort study if they were enrolled at the Malawi site (Zomba Central Hospital) and were taking ART for at least 6 months at admission. Patients who met inclusion criteria had frozen plasma samples tested for HIV-1 viral load. Those with HIV-1 RNA of at least 1000 copies per mL had drug resistance testing by ultra-deep sequencing, with drug resistance defined as intermediate or high-level resistance using the Stanford HIVDR program. Mortality risk was calculated 56 days from enrolment. Patients were censored at death, at 56 days, or at last contact if lost to follow-up. The modelling strategy addressed the causal association between HIV multidrug resistance and mortality, excluding factors on the causal pathway (most notably, CD4 cell count, clinical signs of advanced HIV, and poor functional and nutritional status).

FINDINGS

Of 1316 patients with HIV enrolled in the STAMP trial at the Malawi site between Oct 26, 2015, and Sept 19, 2017, 786 had taken ART for at least 6 months. 252 (32%) of 786 patients had virological failure (viral load ≥1000 copies per mL). Mean age was 41·5 years (SD 11·4) and 528 (67%) of 786 were women. Of 237 patients with HIV drug resistance results available, 195 (82%) had resistance to lamivudine, 128 (54%) to tenofovir, and 219 (92%) to efavirenz. Resistance to at least two drugs was common (196, 83%), and this was associated with increased mortality (adjusted hazard ratio 1·7, 95% CI 1·2-2·4; p=0·0042).

INTERPRETATION

Interventions are urgently needed and should target ART clinic, hospital, and post-hospital care, including differentiated care focusing on patients with advanced HIV, rapid viral load testing, and routine access to drug resistance testing. Prompt diagnosis and switching to alternative ART could reduce early mortality among inpatients with HIV.

FUNDING

Joint Global Health Trials Scheme of the Medical Research Council, UK Department for International Development, and Wellcome Trust.

Xpert MTB/RIF and Xpert MTB/RIF Ultra assays for active tuberculosis and rifampicin resistance in children

BACKGROUND

Every year, at least one million children become ill with tuberculosis and around 200,000 children die. Xpert MTB/RIF and Xpert Ultra are World Health Organization (WHO)-recommended rapid molecular tests that simultaneously detect tuberculosis and rifampicin resistance in adults and children with signs and symptoms of tuberculosis, at lower health system levels. To inform updated WHO guidelines on molecular assays, we performed a systematic review on the diagnostic accuracy of these tests in children presumed to have active tuberculosis.

OBJECTIVES

Primary objectives • To determine the diagnostic accuracy of Xpert MTB/RIF and Xpert Ultra for (a) pulmonary tuberculosis in children presumed to have tuberculosis; (b) tuberculous meningitis in children presumed to have tuberculosis; (c) lymph node tuberculosis in children presumed to have tuberculosis; and (d) rifampicin resistance in children presumed to have tuberculosis - For tuberculosis detection, index tests were used as the initial test, replacing standard practice (i.e. smear microscopy or culture) - For detection of rifampicin resistance, index tests replaced culture-based drug susceptibility testing as the initial test Secondary objectives • To compare the accuracy of Xpert MTB/RIF and Xpert Ultra for each of the four target conditions • To investigate potential sources of heterogeneity in accuracy estimates - For tuberculosis detection, we considered age, disease severity, smear-test status, HIV status, clinical setting, specimen type, high tuberculosis burden, and high tuberculosis/HIV burden - For detection of rifampicin resistance, we considered multi-drug-resistant tuberculosis burden • To compare multiple Xpert MTB/RIF or Xpert Ultra results (repeated testing) with the initial Xpert MTB/RIF or Xpert Ultra result SEARCH METHODS: We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, the WHO International Clinical Trials Registry Platform, ClinicalTrials.gov, and the International Standard Randomized Controlled Trials Number (ISRCTN) Registry up to 29 April 2019, without language restrictions.

SELECTION CRITERIA

Randomized trials, cross-sectional trials, and cohort studies evaluating Xpert MTB/RIF or Xpert Ultra in HIV-positive and HIV-negative children younger than 15 years. Reference standards comprised culture or a composite reference standard for tuberculosis and drug susceptibility testing or MTBDRplus (molecular assay for detection of Mycobacterium tuberculosis and drug resistance) for rifampicin resistance. We included studies evaluating sputum, gastric aspirate, stool, nasopharyngeal or bronchial lavage specimens (pulmonary tuberculosis), cerebrospinal fluid (tuberculous meningitis), fine needle aspirates, or surgical biopsy tissue (lymph node tuberculosis).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed study quality using the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2). For each target condition, we used the bivariate model to estimate pooled sensitivity and specificity with 95% confidence intervals (CIs). We stratified all analyses by type of reference standard. We assessed certainty of evidence using the GRADE approach.

MAIN RESULTS

For pulmonary tuberculosis, 299 data sets (68,544 participants) were available for analysis; for tuberculous meningitis, 10 data sets (423 participants) were available; for lymph node tuberculosis, 10 data sets (318 participants) were available; and for rifampicin resistance, 14 data sets (326 participants) were available. Thirty-nine studies (80%) took place in countries with high tuberculosis burden. Risk of bias was low except for the reference standard domain, for which risk of bias was unclear because many studies collected only one specimen for culture. Detection of pulmonary tuberculosis For sputum specimens, Xpert MTB/RIF pooled sensitivity (95% CI) and specificity (95% CI) verified by culture were 64.6% (55.3% to 72.9%) (23 studies, 493 participants; moderate-certainty evidence) and 99.0% (98.1% to 99.5%) (23 studies, 6119 participants; moderate-certainty evidence). For other specimen types (nasopharyngeal aspirate, 4 studies; gastric aspirate, 14 studies; stool, 11 studies), Xpert MTB/RIF pooled sensitivity ranged between 45.7% and 73.0%, and pooled specificity ranged between 98.1% and 99.6%. For sputum specimens, Xpert Ultra pooled sensitivity (95% CI) and specificity (95% CI) verified by culture were 72.8% (64.7% to 79.6%) (3 studies, 136 participants; low-certainty evidence) and 97.5% (95.8% to 98.5%) (3 studies, 551 participants; high-certainty evidence). For nasopharyngeal specimens, Xpert Ultra sensitivity (95% CI) and specificity (95% CI) were 45.7% (28.9% to 63.3%) and 97.5% (93.7% to 99.3%) (1 study, 195 participants). For all specimen types, Xpert MTB/RIF and Xpert Ultra sensitivity were lower against a composite reference standard than against culture. Detection of tuberculous meningitis For cerebrospinal fluid, Xpert MTB/RIF pooled sensitivity and specificity, verified by culture, were 54.0% (95% CI 27.8% to 78.2%) (6 studies, 28 participants; very low-certainty evidence) and 93.8% (95% CI 84.5% to 97.6%) (6 studies, 213 participants; low-certainty evidence). Detection of lymph node tuberculosis For lymph node aspirates or biopsies, Xpert MTB/RIF pooled sensitivity and specificity, verified by culture, were 90.4% (95% CI 55.7% to 98.6%) (6 studies, 68 participants; very low-certainty evidence) and 89.8% (95% CI 71.5% to 96.8%) (6 studies, 142 participants; low-certainty evidence). Detection of rifampicin resistance Xpert MTB/RIF pooled sensitivity and specificity were 90.0% (67.6% to 97.5%) (6 studies, 20 participants; low-certainty evidence) and 98.3% (87.7% to 99.8%) (6 studies, 203 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

We found Xpert MTB/RIF sensitivity to vary by specimen type, with gastric aspirate specimens having the highest sensitivity followed by sputum and stool, and nasopharyngeal specimens the lowest; specificity in all specimens was > 98%. Compared with Xpert MTB/RIF, Xpert Ultra sensitivity in sputum was higher and specificity slightly lower. Xpert MTB/RIF was accurate for detection of rifampicin resistance. Xpert MTB/RIF was sensitive for diagnosing lymph node tuberculosis. For children with presumed tuberculous meningitis, treatment decisions should be based on the entirety of clinical information and treatment should not be withheld based solely on an Xpert MTB/RIF result. The small numbers of studies and participants, particularly for Xpert Ultra, limits our confidence in the precision of these estimates.

Tuberculosis active case-finding interventions and approaches for prisoners in sub-Saharan Africa: a systematic scoping review

BACKGROUND

In sub-Saharan Africa (SSA), most prisons are overcrowded with poor ventilation and put prisoners disproportionally at risk of exposure to Mycobacterium tuberculosis (TB) and developing TB infection but are mostly missed due to poor access to healthcare. Active case-finding (ACF) of TB in prisons facilitates early diagnosis and treatment of inmates and prevent the spread. We explored literature and described evidence on TB ACF interventions and approaches for prisoners in SSA prisons.

METHODS

Guided by the Arksey and O'Malley framework, we searched PubMed, Google Scholar, SCOPUS, Academic search complete, CINAHL and MEDLINE with full text via EBSCOhost for articles on prisoners and ACF from 2000 to May 2019 with no language restriction. Two investigators independently screened the articles at the abstract and full-text stages in parallel guided by the eligibility criteria as well as performed the methodological quality appraisal of the included studies using the latest mixed-method appraisal tool. We extracted all relevant data, organized them into themes and sub-themes, and presented a narrative summary of the results.

RESULTS

Of the 391 eligible articles found, 31 met the inclusion criteria. All 31 articles were published between 2006 and 2019 with the highest six (19.4%) in 2015. We found evidence in 11 countries. That is, Burkina Faso, Cameroon, Coˆte d'Ivoire, the Democratic Republic of the Congo, Ethiopia, Ghana, Malawi, Nigeria, South Africa, Uganda, and Zambia with most 41.9% (13/31) recorded in Ethiopia. These intervention studies were conducted in 134 prisons between 2001 and 2018 using either a single or combination of mass, facility-led, entry, peer educators for routine screening, and exit ACF approaches. The majority (74%) of the studies utilized only a mass screening approach. The most (68%) reported study outcome was smear-positive TB cases only (68%). We found no evidence in 16 SSA countries although they are classified among the three high-burden country lists for TB TB/HIV and Multidrug resistant-TB group.

CONCLUSION

Our review highlights a dearth of evidence on TB ACF interventions in most SSA countries prisons. Hence, there is the need to scaling-up ACF interventions in SSA prisons, particularly countries included in the three high-burden country lists for TB, TB/HIV, and MDR-TB.

Determine TB-LAM point-of-care tuberculosis assay predicts poor outcomes in outpatients during their first year of antiretroviral therapy in South Africa

BACKGROUND

Determine TB-LAM is the first point-of-care test (POC) for HIV-associated tuberculosis (TB) and rapidly identifies TB in those at high-risk for short-term mortality. While the relationship between urine-LAM and mortality has been previously described, the outcomes of those undergoing urine-LAM testing have largely been assessed during short follow-up periods within diagnostic accuracy studies. We therefore sought to assess the relationship between baseline urine-LAM results and subsequent hospitalization and mortality under real-world conditions among outpatients in the first year of ART.

METHODS

Consecutive, HIV-positive adults with a CD4 count < 100 cells/uL presenting for ART initiation were enrolled. TB diagnoses and outcomes (hospitalization, loss-to-follow and mortality) were recorded during the first year following enrolment. Baseline urine samples were retrospectively tested using the urine-LAM POC assay. Kaplan Meier survival curves were used to assess the cumulative probability of hospitalization or mortality in the first year of follow-up, according to urine-LAM status. Cox regression analyses were performed to determine independent predictors of hospitalization and mortality at  three months and one year of follow-up.

RESULTS

468 patients with a median CD4 count of 59 cells/uL were enrolled. There were 140 patients (29.9%) with newly diagnosed TB in the first year of follow-up of which 79 (56.4%) were microbiologically-confirmed. A total of 18% (n = 84) required hospital admission and 12.2% (n = 57) died within a year of study entry. 38 out of 468 (8.1%) patients retrospectively tested urine-LAM positive - including 19.0% of those with microbiologically-proven TB diagnoses (n = 15/79) and 23.0% (n = 14/61) of those with clinical-only TB diagnoses; 9 of 38 (23.7%) of patients retrospectively testing LAM positive were never diagnosed with TB under routine program conditions. Among all patients (n = 468) in the first year of follow-up, a positive urine-LAM result was strongly associated with all-cause hospitalization and mortality with a corresponding adjusted hazard ratio (aHR) of 3.7 (95%CI, 1.9-7.1) and 2.6 (95%, 1.2-5.7), respectively.

CONCLUSIONS

Systematic urine-LAM testing among ART-naïve HIV-positive outpatients with CD4 counts < 100 cells/uL detected TB cases that were missed under routine programme conditions and was highly predictive for subsequent hospitalization and mortality in the first year of ART.

Should Urine-LAM Tests Be Used in TB Symptomatic HIV-Positive Patients When No CD4 Count Is Available? A Prospective Observational Cohort Study From Malawi

Supplemental Digital Content is Available in the Text.

Current eligibility criteria for urine lateral-flow lipoarabinomannan assay (LF-LAM) in ambulatory, HIV-positive patients rely on the CD4 count. We investigated the diagnostic yield of LF-LAM and the 6-month mortality in ambulatory, TB symptomatic, HIV-positive patients regardless of their CD4 count.

Tuberculosis-HIV Co-Infection: Progress and Challenges After Two Decades of Global Antiretroviral Treatment Roll-Out

Despite wide antiretroviral scale-up during the past two decades resulting in declining new infections and mortality globally, HIV-associated tuberculosis remains as a major public health concern. Tuberculosis is the leading HIV-associated opportunistic infection and the main cause of death globally and, particularly, in resource-limited settings. Several challenges exist regarding diagnosis, global implementation of latent tuberculosis treatment, management of active tuberculosis, delivery of optimal patient-centered TB and HIV prevention and care in high burden countries. In this article we review the advances on pathogenesis, diagnosis, and treatment after nearly two decades of global roll-out of antiretroviral therapy and discuss the current challenges for the global control of tuberculosis-HIV co-infection.

Mycobacterium tuberculosis bloodstream infection prevalence, diagnosis, and mortality risk in seriously ill adults with HIV: a systematic review and meta-analysis of individual patient data

BACKGROUND

The clinical and epidemiological significance of HIV-associated Mycobacterium tuberculosis bloodstream infection (BSI) is incompletely understood. We hypothesised that M tuberculosis BSI prevalence has been underestimated, that it independently predicts death, and that sputum Xpert MTB/RIF has suboptimal diagnostic yield for M tuberculosis BSI.

METHODS

We did a systematic review and individual patient data (IPD) meta-analysis of studies performing routine mycobacterial blood culture in a prospectively defined patient population of people with HIV aged 13 years or older. Studies were identified through searching PubMed and Scopus up to Nov 10, 2018, without language or date restrictions and through manual review of reference lists. Risk of bias in the included studies was assessed with an adapted QUADAS-2 framework. IPD were requested for all identified studies and subject to harmonised inclusion criteria: age 13 years or older, HIV positivity, available CD4 cell count, a valid mycobacterial blood culture result (excluding patients with missing data from lost or contaminated blood cultures), and meeting WHO definitions for suspected tuberculosis (presence of screening symptom). Predicted probabilities of M tuberculosis BSI from mixed-effects modelling were used to estimate prevalence. Estimates of diagnostic yield of sputum testing with Xpert (or culture if Xpert was unavailable) and of urine lipoarabinomannan (LAM) testing for M tuberculosis BSI were obtained by two-level random-effect meta-analysis. Estimates of mortality associated with M tuberculosis BSI were obtained by mixed-effect Cox proportional-hazard modelling and of effect of treatment delay on mortality by propensity-score analysis. This study is registered with PROSPERO, number 42016050022.

FINDINGS

We identified 23 datasets for inclusion (20 published and three unpublished at time of search) and obtained IPD from 20, representing 96·2% of eligible IPD. Risk of bias for the included studies was assessed to be generally low except for on the patient selection domain, which was moderate in most studies. 5751 patients met harmonised IPD-level inclusion criteria. Technical factors such as number of blood cultures done, timing of blood cultures relative to blood sampling, and patient factors such as inpatient setting and CD4 cell count, explained significant heterogeneity between primary studies. The predicted probability of M tuberculosis BSI in hospital inpatients with HIV-associated tuberculosis, WHO danger signs, and a CD4 count of 76 cells per μL (the median for the cohort) was 45% (95% CI 38-52). The diagnostic yield of sputum in patients with M tuberculosis BSI was 77% (95% CI 63-87), increasing to 89% (80-94) when combined with urine LAM testing. Presence of M tuberculosis BSI compared with its absence in patients with HIV-associated tuberculosis increased risk of death before 30 days (adjusted hazard ratio 2·48, 95% CI 2·05-3·08) but not after 30 days (1·25, 0·84-2·49). In a propensity-score matched cohort of participants with HIV-associated tuberculosis (n=630), mortality increased in patients with M tuberculosis BSI who had a delay in anti-tuberculosis treatment of longer than 4 days compared with those who had no delay (odds ratio 3·15, 95% CI 1·16-8·84).

INTERPRETATION

In critically ill adults with HIV-tuberculosis, M tuberculosis BSI is a frequent manifestation of tuberculosis and predicts mortality within 30 days. Improved diagnostic yield in patients with M tuberculosis BSI could be achieved through combined use of sputum Xpert and urine LAM. Anti-tuberculosis treatment delay might increase the risk of mortality in these patients.

FUNDING

This study was supported by Wellcome fellowships 109105Z/15/A and 105165/Z/14/A.

Management of active tuberculosis in adults with HIV

Every year, about 1 million people living with HIV worldwide develop tuberculosis. Although the drug regimens used to treat tuberculosis in these patients are the same as those used in HIV-negative patients, cotreatment of tuberculosis with antiretroviral therapy involves challenges including the optimal timing of antiretroviral initiation, drug-drug interactions, drug tolerability, and the prevention and treatment of tuberculosis-associated immune reconstitution syndrome. Furthermore, mortality is high in people with HIV who are diagnosed with tuberculosis during a hospital admission, and in those with tuberculous meningitis. Studies in this field have better characterised these challenges and informed optimal management and guideline revisions. In patients with tuberculosis, antiretroviral therapy improves survival, is well tolerated, and can be adjusted to manage drug-drug interactions with rifampicin. Prednisone is effective in both preventing and treating the paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome.

Systematic, Point-of-Care Urine Lipoarabinomannan (Alere TB-LAM) Assay for Diagnosing Tuberculosis in Severely Immunocompromised HIV-Positive Ambulatory Patients

Point-of-care urine-lipoarabinomannan (LAM) Alere Determine TB-LAM assay has shown utility diagnosing tuberculosis (TB) in HIV-positive, severely immunocompromised, TB-symptomatic patients. We assessed LAM results in severely immunocompromised patients, who had LAM systematically performed at new or follow-up HIV consultations. This was a prospective, observational study on consecutive ambulatory, > 15-year-old HIV-positive patients with CD4 < 100 cells/µL in Mozambique. Clinical assessments and LAM were performed for all and microscopy, Xpert, sputum culture, and chest X-ray for LAM-positive participants. Patients were followed up for 6 months. Of 360 patients, half were ART-naive. Lipoarabinomannan positivity was 11.9% (43/360), higher among symptomatic patients compared with asymptomatic: 18.5% (30/162), and 6.6% (13/198), respectively, P = 0.001. Tuberculosis was bacteriologically confirmed in 6/35 LAM-positive patients (2 of them asymptomatic). Lipoarabinomannan positivity was associated with higher risk of mortality (adjusted odds ratio [aOR]: 4.6, 95% CI: 1.3–15.6, P = 0.015). Systematic urine-LAM allows for rapid TB treatment initiation in severely immunocompromised HIV ambulatory patients and identifies patients at a higher risk of death.

Diagnostic accuracy of a novel tuberculosis point-of-care urine lipoarabinomannan assay for people living with HIV: A meta-analysis of individual in- and outpatient data

BACKGROUND

Tuberculosis (TB) is the most common cause of death in people living with HIV (PLHIV), yet TB often goes undiagnosed since many patients are not able to produce a sputum specimen, and traditional diagnostics are costly or unavailable. A novel, rapid lateral flow assay, Fujifilm SILVAMP TB LAM (SILVAMP-LAM), detects the presence of TB lipoarabinomannan (LAM) in urine, and is substantially more sensitive for diagnosing TB in PLHIV than an earlier LAM assay (Alere Determine TB LAM lateral flow assay [LF-LAM]). Here, we present an individual participant data meta-analysis of the diagnostic accuracy of SILVAMP-LAM in adult PLHIV, including both published and unpublished data.

METHODS AND FINDINGS

Adult PLHIV (≥18 years) were assessed in 5 prospective cohort studies in South Africa (3 cohorts), Vietnam, and Ghana, carried out during 2012 to 2017. Of the 1,595 PLHIV who met eligibility criteria, the majority (61%) were inpatients, median age was 37 years (IQR 30-43), 43% had a CD4 count ≤ 100 cells/μl, and 35% were receiving antiretroviral therapy. Most participants (94%) had a positive WHO symptom screen for TB on enrollment, and 45% were diagnosed with microbiologically confirmed TB, using mycobacterial culture or Xpert MTB/RIF testing of sputum, urine, or blood. Previously published data from inpatients were combined with unpublished data from outpatients. Biobanked urine samples were tested, using blinded double reading, with SILVAMP-LAM and LF-LAM. Applying a microbiological reference standard for assessment of sensitivity, the overall sensitivity for TB detection was 70.7% (95% CI 59.0%-80.8%) for SILVAMP-LAM compared to 34.9% (95% CI 19.5%-50.9%) for LF-LAM. Using a composite reference standard (which included patients with both microbiologically confirmed as well as clinically diagnosed TB), SILVAMP-LAM sensitivity was 65.8% (95% CI 55.9%-74.6%), and that of LF-LAM 31.4% (95% CI 19.1%-43.7%). In patients with CD4 count ≤ 100 cells/μl, SILVAMP-LAM sensitivity was 87.1% (95% CI 79.3%-93.6%), compared to 56.0% (95% CI 43.9%-64.9%) for LF-LAM. In patients with CD4 count 101-200 cells/μl, SILVAMP-LAM sensitivity was 62.7% (95% CI 52.4%-71.9%), compared to 25.3% (95% CI 15.8%-34.9%) for LF-LAM. In those with CD4 count > 200 cells/μl, SILVAMP-LAM sensitivity was 43.9% (95% CI 34.3%-53.9%), compared to 10.9% (95% CI 5.2%-18.4%) for LF-LAM. Using a microbiological reference standard, the specificity of SILVAMP-LAM was 90.9% (95% CI 87.2%-93.7%), and that of LF-LAM 95.3% (95% CI 92.2%-97.7%). Limitations of this study include the use of biobanked, rather than fresh urine samples, and testing by skilled laboratory technicians in research laboratories, rather than at the point of care.

CONCLUSIONS

In this study, we found that SILVAMP-LAM identified a substantially higher proportion of TB patients in PLHIV than LF-LAM. The sensitivity of SILVAMP-LAM was highest in patients with CD4 count ≤ 100 cells/μl. Further work is needed to demonstrate accuracy when implemented as a point-of-care test.

Closing gaps in the tuberculosis care cascade: an action-oriented research agenda

The care cascade-which evaluates outcomes across stages of patient engagement in a health system-is an important framework for assessing quality of tuberculosis (TB) care. In recent years, there has been progress in measuring care cascades in high TB burden countries; however, there are still shortcomings in our knowledge of how to reduce poor patient outcomes. In this paper, we outline a research agenda for understanding why patients fall through the cracks in the care cascade. The pathway for evidence generation will require new systematic reviews, observational cohort studies, intervention development and testing, and continuous quality improvement initiatives embedded within national TB programs. Certain gaps, such as pretreatment loss to follow-up and post-treatment disease recurrence, should be a priority given a relative paucity of high-quality research to understand and address poor outcomes. Research on interventions to reduce death and loss to follow-up during treatment should move beyond a focus on monitoring (or observation) strategies, to address patient needs including psychosocial and nutritional support. While key research questions vary for each gap, some patient populations may experience disparities across multiple stages of care and should be a priority for research, including men, individuals with a prior treatment history, and individuals with drug-resistant TB. Closing gaps in the care cascade will require investments in a bold and innovative action-oriented research agenda.

A multi-parameter diagnostic clinical decision tree for the rapid diagnosis of tuberculosis in HIV-positive patients presenting to an emergency centre

Background: Early diagnosis is essential to reduce the morbidity and mortality of HIV-associated tuberculosis. We developed a multi-parameter clinical decision tree to facilitate rapid diagnosis of tuberculosis using point-of-care diagnostic tests in HIV-positive patients presenting to an emergency centre. Methods: A cross-sectional study was performed in a district hospital emergency centre in a high-HIV-prevalence community in South Africa. Consecutive HIV-positive adults with ≥1 WHO tuberculosis symptoms were enrolled over a 16-month period. Point-of-care ultrasound (PoCUS) and urine lateral flow lipoarabinomannan (LF-LAM) assay were done according to standardized protocols. Participants also received a chest X-ray. Reference standard was the detection of Mycobacterium tuberculosis using Xpert MTB/RIF or culture. Logistic regressions models were used to investigate the independent association between prevalent microbiologically confirmed tuberculosis and clinical and biological variables of interest. A decision tree model to predict tuberculosis was developed using the classification and regression tree algorithm. Results: There were 414 participants enrolled: 171 male, median age 36 years, median CD4 cell count 86 cells/mm3. Tuberculosis prevalence was 42% (n=172). Significant variables used to build the classification tree included ≥2 WHO symptoms, antiretroviral therapy use, LF-LAM, PoCUS independent features (pericardial effusion, ascites, intra-abdominal lymphadenopathy) and chest X-ray. LF-LAM was positioned after WHO symptoms (75% true positive rate, representing 17% of study population). Chest X-ray should be performed next if LF-LAM is negative. The presence of ≤1 PoCUS independent feature in those with ‘possible or unlikely tuberculosis’ on chest x-ray represented 47% of non-tuberculosis participants (true negative rate 83%). In a prediction tree which only included true point-of-care tests, a negative LF-LAM and the presence of ≤2 independent PoCUS features had a 71% true negative rate (representing 53% of sample). Conclusions: LF-LAM should be performed in all adults with suspected HIV-associated tuberculosis (regardless of CD4 cell count) presenting to the emergency centre.

The shift in tuberculosis timing among people living with HIV in the course of antiretroviral therapy scale-up in Malawi

Introduction

Although the use of antiretroviral therapy (ART) reduces HIV‐associated tuberculosis (TB), patients living with HIV receiving ART remain at a higher risk of developing TB compared to those without HIV. We investigated the incidence of TB and the proportion of HIV‐associated TB cases among patients living with HIV who are receiving ART.

Methods

The study used TB registration and ART programme data collected between 2008 and 2017 from an integrated, public clinic in urban Lilongwe, Malawi. ART initiation was based on either WHO clinical staging or CD4 cell count. The CD4 thresholds for ART initiation eligibility was initially 250 cells/μL then changed to 350 cells/μL in 2011, 500 cells/μL in 2014 and to universal treatment upon diagnosis from 2016. Using TB registration data, we calculated the proportion of TB/HIV patients who were already on ART when they registered for TB treatment by year of TB registration. ART registration data were used to examine TB incidence by calendar year of ART follow‐up and by time on ART.

Results

The overall proportion of TB/patients living with HIV who started TB treatment while on ART increased from 21% in 2008 to 81% in 2017 but numbers remained relatively constant at 500 TB cases annually. The overall incidence rate of TB among patients on ART was 1.35/100 person‐years (95% CI 1.28 to 1.42). The incidence of TB by time on ART decreased from 6.4/100 person‐years in the first three months of ART to 0.4/100 person‐years after eight years on ART. TB incidence was highest in the first month on ART. The annual rate of TB among patients on ART rapidly decreased each calendar year and stabilized at 1% after 2013. Although the risk of developing TB decreased with year of ART initiation in univariable analysis, there was no significant association after adjusting for sex, age and reason for ART eligibility.

Conclusions

The decline in TB incidence over calendar years suggests protective effects of early ART initiation. The high TB incidence within the first month of ART highlights the need for more sensitive tools such as X‐ray and GeneXpert to identify patients living with HIV who have clinical and subclinical TB disease at ART initiation.

Adoption and uptake of the lateral flow urine LAM test in countries with high tuberculosis and HIV/AIDS burden: current landscape and barriers

Background: Since 2015, the World Health Organization (WHO) has recommended a commercially available lateral-flow urine LAM test (Alere-LAM) to assist in the diagnosis of tuberculosis (TB) in severely ill people living with HIV (PLHIV). The test can rapidly detect TB in severely ill PLHIV and can identify PLHIV most at-risk of death, leading to mortality reductions. However, its uptake in countries with high burdens of TB and HIV has been slow. To assess the current use landscape and identify barriers to the adoption of Alere-LAM, we conducted a questionnaire-based study in 31 high TB and HIV/AIDS burden countries. Methods: Between November 2018 and December 2019, we collected responses to a semi-structured questionnaire that had been emailed to staff and affiliates of National TB Programs or HIV/AIDS Programs, Ministries of Health, and TB or HIV institutes of 31 high TB/HIV burden countries. Questions concerned country policies, adoption, and current use of Alere-LAM testing, as well as testing algorithms and barriers preventing Alere-LAM uptake. Results: We received questionnaire responses from 24 out of 31 (77%) high TB/HIV burden countries. Of these 24 countries, 11 (46%) had adopted Alere-LAM policies, with only five (21%) countries currently using Alere-LAM testing. Testing algorithms were generally aligned with WHO recommendations. Fifteen countries (63%) said they were planning to implement Alere-LAM testing in the near future. The most commonly cited constraint to adoption and implementation was budget limitations. Additional barriers to Alere-LAM implementation included lack of country-specific data and piloting, administrative hurdles such as regulatory agency approval, lack of coordination between National TB and HIV programs, and small perceived patient population. Conclusion: Responses to our questionnaire demonstrate the persistent gap between country-level policy and real-world use of Alere-LAM, as well as specific barriers that must be addressed to scale-up testing in PLHIV.