Diagnosis and clinical outcomes of extrapulmonary tuberculosis in antiretroviral therapy programmes in low- and middle-income countries: a multicohort study

Interferon-gamma release assays as a tool for differential diagnosis of gastrointestinal tuberculosis

In this editorial, we comment on an article published in a recent issue of the World Journal of Clinical Cases. There is a pressing need for reliable tools for diagnosing tuberculosis (TB) of the gastrointestinal tract. Despite advancements in the diagnosis and treatment, TB remains a global health challenge. Ali et al demonstrated that TB may mimic gastrointestinal conditions, such as gastric outlet obstruction, causing a delay in the diagnosis. Furthermore, the latter complication is frequently observed during infections, including Helicobacter pylori, and rarely is related to TB, as in the presented case. In line with this, we think that laboratory tests based on interferon-gamma release assays can be a helpful tool for diagnosing latent TB paced in the gastrointestinal tract. Innovative strategies and approaches for diagnosing latent/active extra pulmonary TB are crucial for establishing the diagnosis early and enhancing treatment strategies to mitigate the global burden of TB.

Factors associated with hospitalization and mortality in adult and pediatric extrapulmonary tuberculosis at a tertiary care hospital in Central India

BACKGROUND

Comorbidities complicate the management of tuberculosis (TB) and have become an essential part of the end TB strategy to eradicate TB. However, pulmonary TB has received the most attention, and little is known about the impact of comorbidities and other factors on outcomes in patients with extrapulmonary tuberculosis (EPTB).

OBJECTIVES

Our aim was to analyze the factors associated with hospitalization and mortality in EPTB at a hospital in Central India, using non-TB patients with similar clinical presentations as a comparison.

METHODS

Patients with presumptive EPTB were prospectively enrolled and followed up until the end of treatment or for at least 6 months. Detailed demographic and clinical information was collected for all participants, and patients were categorized as TB or non-TB using a composite reference standard. Multivariate logistic regression was used to analyze the impact of various clinical findings and risk factors on hospitalization and mortality.

RESULTS

A total of 276 patients were categorized as TB cases and 175 as non-TB cases. Factors associated with hospitalization in children were younger age and non-adenitis site of disease. In adults, factors associated with mortality were older age, non-adenitis site of disease and HIV infection regardless of TB diagnosis, while diabetes mellitus increased the odds of mortality in EPTB patients.

CONCLUSION

Our results show that comorbidities increase the odds of death in both TB and non-TB patients in low-resource settings. This argues for a shift away from the traditional vertical management of diseases in these areas and supports a continued focus on building robust healthcare systems.

Comparing the cost-effectiveness of the MPT64-antigen detection test to Xpert MTB/RIF and ZN-microscopy for the diagnosis of Extrapulmonary Tuberculosis: An economic evaluation modelling study

Extrapulmonary Tuberculosis (EPTB) poses challenges from patient and health system perspectives. The cost-effectiveness analysis of the Xpert MTB/RIF (Xpert) test to diagnose pulmonary tuberculosis is documented. However, there are no economic evaluations for EPTB. Considering the reported better diagnostic sensitivity of the MPT64 test, this study explored its cost-effectiveness as an alternative diagnostic test. We conducted this economic evaluation to assess the cost-effectiveness of the MPT64 test compared to Xpert and ZN microscopy for EPTB adult patients. We utilised a Markov modelling approach to capture short- and long-term costs and benefits from a health system perspective. For the model inputs, we combined data from our cohort studies in Tanzania and peer-reviewed EPTB literature. We calculated the Incremental Cost Effectiveness Ratio (ICER) by comparing the cost (in USD) of each diagnostic test and Quality Adjusted Life Years (QALYs) as health gain. We found the MPT64 test cost-effective for EPTB diagnosis and absolutely dominated ZN microscopy and Xpert using the baseline model inputs. A scenario analysis showed that the Xpert test might be the most cost-effective at its higher test sensitivity, which corresponds to using it to diagnose lymph node aspirates. The prevalence of HIV among EPTB cases, their probability of treatment, costs of ART, and the probability of the MPT64 test in detecting EPTB patients were the main parameters associated with the highest impact on ICER in one-way deterministic analysis. The most cost-effective option for EPTB at the baseline parameters was the MPT64 diagnostic test. Including the MPT64 test in EPTB diagnostic pathways for previously untreated patients can lead to better resource use. The Xpert test was the most cost-effective diagnostic intervention at a higher diagnostic test sensitivity in scenario analyses based on different sites of infection, such as for the lymph node aspirates.

Diagnostic Yield of Urine Xpert MTB/RIF Ultra in Adults With Suspected Extrapulmonary Tuberculosis

We assessed the diagnostic yield of urine GeneXpert MTB/RIF Ultra and factors associated with a positive test among adult patients suspected to have extrapulmonary tuberculosis. Urine Ultra was positive in 14% of participants with definite or probable tuberculosis. Hospitalization, disseminated tuberculosis, and human immunodeficiency virus infection were associated with a positive result.

Mortality among extrapulmonary tuberculosis patients in the HIV endemic setting: lessons from a tertiary level hospital in Mbeya, Tanzania

Extrapulmonary tuberculosis (EPTB) has received less attention than pulmonary tuberculosis due to its non-contagious nature. EPTB can affect any organ and is more prevalent in people living with HIV. Low- and middle-income countries are now facing the double burden of non-communicable diseases (NCDs) and HIV, complicating the management of patients with symptoms that could be compatible with both EPTB and NCDs. Little is known about the risk of death of patients presenting with symptoms compatible with EPTB. We included patients with a clinical suspicion of EPTB from a tertiary level hospital in Mbeya, Tanzania, to assess their risk of dying. A total of 113 (61%) patients were classified as having EPTB, and 72 (39%) as having non-TB, with corresponding mortality rates of 40% and 41%. Associated factors for mortality in the TB groups was hospitalization and male sex. Risk factors for hospitalization was having disease manifestation at any site other than lymph nodes, and comorbidities. Our results imply that NCDs serve as significant comorbidities amplifying the mortality risk in EPTB. To strive towards universal health coverage, focus should be on building robust health systems that can tackle both infectious diseases, such as EPTB, and NCDs.

The clinical presentation and detection of tuberculosis during pregnancy and in the postpartum period in low- and middle-income countries: A systematic review and meta-analysis

For women infected with Mycobacterium tuberculosis, pregnancy is associated with an increased risk of developing or worsening TB disease. TB in pregnancy increases the risk of adverse maternal and neonatal outcomes, however the detection of TB in pregnancy is challenging. We aimed to identify and summarise the findings of studies regarding the clinical presentation and diagnosis of TB during pregnancy and the postpartum period (within 6 months of birth) in low-and middle-income countries (LMICs). A systematic review was conducted searching Ovid MEDLINE, Embase, CINAHL and Global Index Medicus databases. We included any primary research study of women diagnosed with TB during pregnancy or the postpartum period in LMICs that described the clinical presentation or method of diagnosis. Meta-analysis was used to determine pooled prevalence of TB clinical features and health outcomes, as well as detection method yield. Eighty-seven studies of 2,965 women from 27 countries were included. 70.4% of women were from South Africa or India and 44.7% were known to be HIV positive. For 1,833 women where TB type was reported, pulmonary TB was most common (79.6%). Most studies did not report the prevalence of presenting clinical features. Where reported, the most common were sputum production (73%) and cough (68%). Having a recent TB contact was found in 45% of women. Only six studies screened for TB using diagnostic testing for asymptomatic antenatal women and included mainly HIV-positive women ‒ 58% of women with bacteriologically confirmed TB did not report symptoms and only two were in HIV-negative women. Chest X-ray had the highest screening yield; 60% abnormal results of 3036 women tested. Screening pregnant women for TB-related symptoms and risk factors is important but detection yields are limited. Chest radiography and bacteriological detection methods can improve this, but procedures for optimal utilisation remain uncertain in this at-risk population. Trial registration: Prospero registration number: CRD42020202493.

Ultrasononography in Managing Extrapulmonary Tuberculosis: A Randomized, Controlled, Parallel, Superiority, Open-Label Trial

BACKGROUND

Patients with suspected extrapulmonary tuberculosis are often treated empirically. We hypothesized that extended focused assessment with sonography for human immunodeficiency virus (HIV) and tuberculosis (eFASH), in combination with other tests, would increase the proportion of correctly managed patients with suspected extrapulmonary tuberculosis.

METHODS

This trial in adults with suspected extrapulmonary tuberculosis was performed in a rural and an urban hospital in Tanzania. Participants were randomized 1:1 to intervention or routine care, stratified by site and HIV status. All participants underwent clinical evaluation, chest radiography, and testing with sputum Xpert MTB/RIF and urine Xpert MTB/RIF Ultra assays. The intervention was a management algorithm based on results of eFASH plus microbiology, adenosine deaminase (ADA), and chest radiography. The primary outcome was the proportion of correctly managed patients. The presence of positive microbiological or ADA results defined definite tuberculosis. An independent end-point review committee determined diagnoses of probable or no tuberculosis. We evaluated outcomes using logistic regression models, adjusted for randomization stratification factors.

RESULTS

From September 2018 to October 2020, a total of 1036 patients were screened and 701 were randomized (350 to the intervention and 351 to the control group). Of participants in the intervention group, 251 (72%) had a positive eFASH outcome. In 258 (74%) of the intervention and 227 (65%) of the control participants antituberculosis was initiated treatment at baseline. More intervention participants had definite tuberculosis (n = 124 [35%]), compared with controls (n = 85 [24%]). There was no difference between groups for the primary outcome (intervention group, 266 of 286 [93%]; control group, 245 of 266 [92%]; odds ratio, 1.14 [95% confidence interval: .60-2.16]; P = .68). There were no procedure-associated adverse events.

CONCLUSIONS

eFASH did not change the proportion of correctly managed patients but increased the proportion of those with definite tuberculosis.

CLINICAL TRIALS REGISTRATION

Pan African Registry: PACTR201712002829221.

Design and implementation of a global site assessment survey among HIV clinics participating in the International epidemiology Databases to Evaluate AIDS (IeDEA) research consortium

INTRODUCTION

Timely descriptions of HIV service characteristics and their evolution over time across diverse settings are important for monitoring the scale-up of evidence-based program strategies, understanding the implementation landscape, and examining service delivery factors that influence HIV care outcomes.

METHODS

The International epidemiology Databases to Evaluate AIDS (IeDEA) consortium undertakes periodic cross-sectional surveys on service availability and care at participating HIV treatment sites to characterize trends and inform the scientific agenda for HIV care and implementation science communities. IeDEA's 2020 general site assessment survey was developed through a consultative, 18-month process that engaged diverse researchers in identifying content from previous surveys that should be retained for longitudinal analyses and in developing expanded and new content to address gaps in the literature. An iterative review process was undertaken to standardize the format of new survey questions and align them with best practices in survey design and measurement and lessons learned through prior IeDEA site assessment surveys.

RESULTS

The survey questionnaire developed through this process included eight content domains covered in prior surveys (patient population, staffing and community linkages, HIV testing and diagnosis, new patient care, treatment monitoring and retention, routine HIV care and screening, pharmacy, record-keeping and patient tracing), along with expanded content related to antiretroviral therapy (differentiated service delivery and roll-out of dolutegravir-based regimens); mental health and substance use disorders; care for pregnant/postpartum women and HIV-exposed infants; tuberculosis preventive therapy; and pediatric/adolescent tuberculosis care; and new content related to Kaposi's sarcoma diagnostics, the impact of COVID-19 on service delivery, and structural barriers to HIV care. The survey was distributed to 238 HIV treatment sites in late 2020, with a 95% response rate.

CONCLUSION

IeDEA's approach for site survey development has broad relevance for HIV research networks and other priority health conditions.

Isolated Tuberculous Myositis: A Systematic Review and Multicenter Cases

Objective

To investigate the clinical features and associated underlying conditions of isolated tuberculous myositis (ITBM), a rare extrapulmonary tuberculosis (TB).

Methods

A systematic literature search and a multicenter survey were performed using a triangulation strategy. Data from the identified ITBM cases were extracted and analyzed to determine the underlying conditions, clinical presentations, treatments, and outcomes.

Results

Based on the systematic review, we identified 58 ITBM, including 9 pediatric, cases in the literature published from 1981 to 2021 25 (43.1%) immunocompromised and 33 (56.9%) non-immunocompromised patients. Immunocompromised cases had a significant shorter symptom duration (median 30.0 vs. 75.0 days) and a higher prevalence of multilocular involvement (20.8% vs. 0%). Among 24 immunocompromised adult patients, dermatomyositis/polymyositis (DM/PM; n=10, 41.7%) were the most common underlying diseases in adults with ITBM identified in the systematic review. Over the past 20 years, 11 Korean adults with ITBM were identified in the multicenter survey. Of 7 immunocompromised cases, two (28.6%) were DM/PM patients. TB death rate of immunocompromised patients was 0.0% and 5/23 (21.7%) in the pediatric and adult ITBM cases identified in the systematic review, respectively, and 3/7 (42.9%) in survey-identified ITBM cases.

Conclusion

ITBM has a unique clinical presentation including fever, tenderness, local swelling, overlying erythema, abscess formation and was associated with a grave outcome, especially in immunocompromised hosts. DM/PM was a highly prevalent underlying disease in both systematic review-identified and survey-identified immunocompromised ITBM patients.

Host-directed therapies in pulmonary tuberculosis: Updates on anti-inflammatory drugs

Tuberculosis (TB) is a lethal disease and remains one of the top ten causes of mortality by an infectious disease worldwide. It can also result in significant morbidity related to persistent inflammation and tissue damage. Pulmonary TB treatment depends on the prolonged use of multiple drugs ranging from 6 months for drug-susceptible TB to 6-20 months in cases of multi-drug resistant disease, with limited patient tolerance resulting from side effects. Treatment success rates remain low and thus represent a barrier to TB control. Adjunct host-directed therapy (HDT) is an emerging strategy in TB treatment that aims to target the host immune response to Mycobacterium tuberculosis in addition to antimycobacterial drugs. Combined multi-drug treatment with HDT could potentially result in more effective therapies by shortening treatment duration, improving cure success rates and reducing residual tissue damage. This review explores the rationale and challenges to the development and implementation of HDTs through a succinct report of the medications that have completed or are currently being evaluated in ongoing clinical trials.

Manipulation and exploitation of host immune system by pathogenic Mycobacterium tuberculosis for its advantage

Mycobacterium tuberculosis (Mtb) can become a long-term infection by evading the host immune response. Coevolution of Mtb with humans has resulted in its ability to hijack the host's immune systems in a variety of ways. So far, every Mtb defense strategy is essentially dependent on a subtle balance that, if shifted, can promote Mtb proliferation in the host, resulting in disease progression. In this review, the authors summarize many important and previously unknown mechanisms by which Mtb evades the host immune response. Besides recently found strategies by which Mtb manipulates the host molecular regulatory machinery of innate and adaptive immunity, including the intranuclear regulatory machinery, costimulatory molecules, the ubiquitin system and cellular intrinsic immune components will be discussed. A holistic understanding of these immune-evasion mechanisms is of foremost importance for the prevention, diagnosis and treatment of tuberculosis and will lead to new insights into tuberculosis pathogenesis and the development of more effective vaccines and treatment regimens.

LATERAL FLOW URINE LIPOARABINOMANNAN ASSAY FOR EXTRAPULMONARY TUBERCULOSIS DIAGNOSIS IN HIV POSITIVE ADULTS

BACKGROUND

The diagnosis of extrapulmonary tuberculosis (EPTB) in Human Immunodeficiency Virus (HIV) patients remains a challenge for clinicians. World Health Organization (WHO) recommends the detection of Lipoarabinomannan (LAM) for diagnosing pulmonary tuberculosis in HIV patients. A new generation of urine LAM tests (FujiLAM®) is available. However, studies regarding its accuracy are limited.

OBJECTIVE

This study aims to evaluate the accuracy of urine LAM test using FujiLAM® for diagnosing EPTB in patients with HIV.

METHODS

A cross-sectional study using urine samples of patients at Cipto Mangunkusumo Hospital, Indonesia, was performed from January 2020 to December 2020. Fresh urine was applied to the FujiLAM®. Subjects were grouped into definitive, probable, and non-TB groups. The diagnostic accuracy of the urine LAM test was compared to other Mycobacterium tuberculosis specimen gold standard tests.

RESULTS

Among 62 patients, 16 patients (25.8%) had definitive diagnosis of EPTB. Amongst those with definitive TB, urine LAM test yielded a sensitivity of 75% (95%CI: 47.62%-92.73%) and specificity of 73.91% (95%CI: 87%-85.73%). Meanwhile, compared to all diagnostic tests (definite + probable TB), FujiLAM® had a sensitivity value of 61% (95%CI 43.36-76.86%) and a specificity value of 92.31% (95%CI 74.87-99.05%).

CONCLUSION

FujiLAM® test is a feasible method for diagnosing EPTB in HIV patients.

Improved diagnosis of extrapulmonary tuberculosis in adults with and without HIV in Mbeya, Tanzania using the MPT64 antigen detection test

Extrapulmonary tuberculosis (EPTB) in People Living with HIV (PLWHIV) is a diagnostic challenge. Our immunochemistry based MPT64 antigen detection test has shown improved sensitivity compared to current laboratory tests in the resource limited diagnostic setting. The aim of this study was to validate the implementability and diagnostic performance of the test in PLWHIV and HIV negative adults in a HIV endemic Tanzanian setting. Adult (>18 y) presumptive EPTB patients were prospectively enrolled at Mbeya Zonal Referral Hospital and followed to the end of treatment or until an alternative diagnosis was reached. Suspected sites of infection were sampled and were subject to routine diagnostics, GeneXpert MTB/RIF assay and the MPT64 test. The performance of the diagnostics tests was assessed using a composite reference standard that included clinical suspicion, mycobacterial culture, response to anti-tuberculosis (TB) therapy, cytological and radiological findings. Patients (N = 168) were categorized as 21 confirmed TB, 23 probable TB and 44 possible TB cases, 69 patients were categorized as non-TB cases and 11 were uncategorized. In the TB group, the three most common infections were adenitis (41%), peritonitis (19%) and pleuritis (14%). The TB and non-TB groups did not differ in HIV seropositivity (46% vs 42%) Among HIV negative and PLWHIV, the MPT64 test had a sensitivity of (91% vs 78%), specificity (75% vs 86%), positive predictive value (80% vs 88%), negative predictive value (89% vs 74%), and accuracy (84% vs 81%), respectively. Performance was not significantly reduced in PLWHIV, and sensitivity was higher than in the currently used tests, including the GeneXpert MTB/RIF assay. The MPT64 test improved the diagnosis of EPTB, irrespective of HIV status. The test performed better than currently used diagnostic test. The test was implementable in a tertiary level hospital with basic pathology services in a HIV endemic Tanzanian setting.

Clinical characteristic, Common sites and Drug resistance profile in Culture-confirmed EPTB/ HIV co-infection patients, Southwest of China

OBJECTIVES

There are few reports on EPTB/HIV co-infection patients, especially the drug resistance profile of culture-confirmed EPTB. The purpose of our study was to analysis the clinical characteristic, common sites and drug resistance profile of culture-confirmed EPTB/HIV co-infection patients in recent years in southwest of China.

METHODS

A total of 201 EPTB/HIV co-infection cases were selected for this study. Patient demographic and clinical characteristics were collected. Mycobacterium tuberculosis drug sensitivity testing was performed using the microporousplate ratio method.

RESULTS

For the 2884 culture-confirmed EPTB cases recruited, patients were predominantly male1921/2884(66.6%). Mean age was 31years. Two hundred and one cases were EPTB/ HIV co-infection patients(7.0 %), from 201 cases male make up 84.6% (170/201), mean age was 42 years (range 13-86/year). During the 7-years period, the mean number of EPTB/ HIV co-infection cases was 29 per year(range 12-49/year) at this institution. Diarrhea, headache and fever were the most common presenting symptom.DST results showed the resistance to any anti-tuberculosis drug was observed in 62(30.8%) patient isolates, while multidrug-resistant TB and extensively drug-resistant TB were found in 14(7.0%) and 10(5.0%) patients, respectively. The distribution of EPTB tissue type mainly in Meningeal and Lymph node, varies between different genders.

CONCLUSIONS

The immune level of EPTB/HIV co-infected patients was low and most were in advanced AIDS stage. Mainly young male, and the site of EPTB was mainly in the Meningeal and Lymph node. The most common symptoms were diarrhea, headache and fever and high rates of drug resistance were found.

Prevalence and Risk Factors of Infection with High Risk Human Papilloma Viruses among HIV-Positive Women with Clinical Manifestations of Tuberculosis in a Middle-Income Country

Women living with HIV-1 are at high risk of infection with human papillomavirus of high carcinogenic risk (HR HPVs). M. tuberculosis (TB) promotes HPV infection and increases the risk to develop HPV-associated cancer. Our knowledge of persisting HR HPVs genotypes, and of the factors promoting HR HPV infection in people living with HIV-1 with clinical TB manifestations is sparse. Here, we analyzed 58 women living with HIV-1 with clinical TB manifestations (WLWH with TB) followed up in specialized centers in Russia, a middle income country endemic for HIV-1 and TB, for the presence in cervical smears of DNA of twelve HR HPV genotypes. DNA encoding HPV16 E5, E6/E7 was sequenced. Sociodemographic data of patients was collected by questionnaire. All women were at C2-C3 stages of HIV-infection (by CDC). The majority were over 30 years old, had secondary education, were unemployed, had sexual partners, experienced 2–3 pregnancies and at least one abortion, and were smokers. The most prevalent was HPV16 detected in the cervical smears of 38% of study participants. Altogether 34.5% of study participants were positive for HR HPV types other than HPV16; however, but none of these types was seen in more than 7% of tested samples. Altogether, 20.7% of study participants were positive for several HR HPV types. Infections with HPVs other than HPV16 were common among WLWH with generalized TB receiving combined ART/TB-therapy, and associated with their ability to work, indirectly reflecting both their health and lifestyle. The overall prevalence of HR HPVs was associated with sexual activity of women reflected by the number of pregnancies, and of HPV 16, with young age; none was associated to CD4+-counts, route of HIV-infection, duration of life with HIV, forms of TB-infection, or duration of ART, characterizing the immune status. Thus, WLWH with TB—especially young—were predisposed to infection with HPV16, advancing it as a basis for a therapeutic HPV vaccine. Phylogenetic analysis of HPV16 E5, E6/E7 DNA revealed no common ancestry; sequences were similar to those of the European and American HPV16 strains, indicating that HPV vaccine for WLWH could be the same as HPV16 vaccines developed for the general population. Sociodemographic and health correlates of HR HPV prevalence in WLWH deserve further analysis to develop criteria/recommendations for prophylactic catch-up and therapeutic HPV vaccination of this highly susceptible and vulnerable population group.

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.

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.

International epidemiology databases to evaluate AIDS (IeDEA) in sub-Saharan Africa, 2012-2019

PURPOSE

The objectives of the International epidemiology databases to evaluate AIDS (IeDEA) are to (i) evaluate the delivery of combination antiretroviral therapy (ART) in children, adolescents and adults in sub-Saharan Africa, (ii) to describe ART regimen effectiveness, durability and tolerability, (iii) to examine HIV-related comorbidities and coinfections and (iv) to examine the pregnancy-related and HIV-related outcomes of women on ART and their infants exposed to HIV or ART in utero or via breast milk.

PARTICIPANTS

IeDEA is organised in four regions (Central, East, Southern and West Africa), with 240 treatment and care sites, six data centres at African, European and US universities, and almost 1.4 million children, adolescents and adult people living with HIV (PLWHIV) enrolled.

FINDINGS TO DATE

The data include socio-demographic characteristics, clinical outcomes, opportunistic events, treatment regimens, clinic visits and laboratory measurements. They have been used to analyse outcomes in PLWHIV-1 or PLWHIV-2 who initiate ART, including determinants of mortality, of switching to second-line and third-line ART, drug resistance, loss to follow-up and the immunological and virological response to different ART regimens. Programme-level estimates of mortality have been corrected for loss to follow-up. We examined the impact of coinfection with hepatitis B and C, and the epidemiology of different cancers and of (multidrug resistant) tuberculosis, renal disease and of mental illness. The adoption of 'Treat All', making ART available to all PLWHIV regardless of CD4+ cell count or clinical stage was another important research topic.

FUTURE PLANS

IeDEA has formulated several research priorities for the 'Treat All' era in sub-Saharan Africa. It recently obtained funding to set up sentinel sites where additional data are prospectively collected on cardiometabolic risks factors as well as mental health and liver diseases, and is planning to create a drug resistance database.

Extrapulmonary tuberculosis in HIV-infected patients in rural Tanzania: The prospective Kilombero and Ulanga antiretroviral cohort

BACKGROUND

In sub-Saharan Africa, diagnosis and management of extrapulmonary tuberculosis (EPTB) in people living with HIV (PLHIV) remains a major challenge. This study aimed to characterize the epidemiology and risk factors for poor outcome of extrapulmonary tuberculosis in people living with HIV (PLHIV) in a rural setting in Tanzania.

METHODS

We included PLHIV >18 years of age enrolled into the Kilombero and Ulanga antiretroviral cohort (KIULARCO) from 2013 to 2017. We assessed the diagnosis of tuberculosis by integrating prospectively collected clinical and microbiological data. We calculated prevalence- and incidence rates and used Cox regression analysis to evaluate the association of risk factors in extrapulmonary tuberculosis (EPTB) with a combined endpoint of lost to follow-up (LTFU) and death.

RESULTS

We included 3,129 subjects (64.5% female) with a median age of 38 years (interquartile range [IQR] 31-46) and a median CD4+ cell count of 229/μl (IQR 94-421) at baseline. During the median follow-up of 1.25 years (IQR 0.46-2.85), 574 (18.4%) subjects were diagnosed with tuberculosis, whereof 175 (30.5%) had an extrapulmonary manifestation. Microbiological evidence by Acid-Fast-Bacillus stain (AFB-stain) or Xpert® MTB/RIF was present in 178/483 (36.9%) patients with pulmonary and in 28/175 (16.0%) of patients with extrapulmonary manifestations, respectively. Incidence density rates for pulmonary Tuberculosis (PTB and EPTB were 17.9/1000person-years (py) (95% CI 14.2-22.6) and 5.8/1000 py (95% CI 4.0-8.5), respectively. The combined endpoint of death and LTFU was observed in 1058 (33.8%) patients, most frequently in the subgroup of EPTB (47.2%). Patients with EPTB had a higher rate of the composite outcome of death/LTFU after TB diagnosis than with PTB [HR 1.63, (1.14-2.31); p = 0.006]. The adjusted hazard ratios [HR (95% CI)] for death/LTFU in EPTB patients were significantly increased for patients aged >45 years [HR 1.95, (1.15-3.3); p = 0.013], whereas ART use was protective [HR 0.15, (0.08-0.27); p <0.001].

CONCLUSIONS

Extrapulmonary tuberculosis was a frequent manifestation in this cohort of PLHIV. The diagnosis of EPTB in the absence of histopathology and mycobacterial culture remains challenging even with availability of Xpert® MTB/RIF. Patients with EPTB had increased rates of mortality and LTFU despite early recognition of the disease after enrollment.

Mycobacterium tuberculosis Dissemination Plays a Critical Role in Pathogenesis

Mycobacterium tuberculosis is primarily a respiratory pathogen. However, 15% of infections worldwide occur at extrapulmonary sites causing additional complications for diagnosis and treatment of the disease. In addition, dissemination of M. tuberculosis out of the lungs is thought to be more than just a rare event leading to extrapulmonary tuberculosis, but rather a prerequisite step that occurs during all infections, producing secondary lesions that can become latent or productive. In this review we will cover the clinical range of extrapulmonary infections and the process of dissemination including evidence from both historical medical literature and animal experiments for dissemination and subsequent reseeding of the lungs through the lymphatic and circulatory systems. While the mechanisms of M. tuberculosis dissemination are not fully understood, we will discuss the various models that have been proposed to address how this process may occur and summarize the bacterial virulence factors that facilitate M. tuberculosis dissemination.