Reduction in extrapulmonary tuberculosis in context of antiretroviral therapy scale-up in rural South Africa

Incidence of self-reported tuberculosis treatment with community-wide universal testing and treatment for HIV and tuberculosis screening in Zambia and South Africa: A planned analysis of the HPTN 071 (PopART) cluster-randomised trial

BACKGROUND

HIV is a potent risk factor for tuberculosis (TB). Therefore, community-wide universal testing and treatment for HIV (UTT) could contribute to TB control, but evidence for this is limited. Community-wide TB screening can decrease population-level TB prevalence. Combining UTT with TB screening could therefore significantly impact TB control in sub-Saharan Africa, but to our knowledge there is no evidence for this combined approach.

METHODS AND FINDINGS

HPTN 071 (PopART) was a community-randomised trial conducted between November 2013 to July 2018; 21 Zambian and South African communities (with a total population of approximately 1 million individuals) were randomised to arms A (community-wide UTT and TB screening), B (community-wide universal HIV testing with treatment following national guidelines and TB screening), or C (standard-of-care). In a cohort of randomly selected adults (18 to 44 years) enrolled between 2013 and 2015 from all 21 communities (total size 38,474; 27,139 [71%] female; 8,004 [21%] HIV positive) and followed-up annually for 36 months to measure the population-level impact of the interventions, data on self-reported TB treatment in the previous 12 months (self-reported TB) were collected by trained research assistants and recorded using a structured questionnaire at each study visit. In this prespecified analysis of the trial, self-reported TB incidence rates were measured by calendar year between 2014 and 2017/2018. A p-value ≤0.05 on hypothesis testing was defined as reaching statistical significance. Between January 2014 and July 2018, 38,287 individuals were followed-up: 494 self-reported TB during 104,877 person-years. Overall incidence rates were similar across all arms in 2014 and 2015 (0.33 to 0.46/100 person-years). In 2016 incidence rates were lower in arm A compared to C overall (adjusted rate ratio [aRR] 0.48 [95% confidence interval (95% CI) 0.28 to 0.81; p = 0.01]), with statistical significance reached. In 2017/2018, while incidence rates were lower in arm A compared to C, statistical significance was not reached (aRR 0.58 [95% CI 0.27 to 1.22; p = 0.13]). Among people living with HIV (PLHIV) incidence rates were lower in arm A compared to C in 2016 (RR 0.56 [95% CI 0.29 to 1.08; p = 0.08]) and 2017/2018 (RR 0.50 [95% CI 0.26 to 0.95; p = 0.04]); statistical significance was only reached in 2017/2018. Incidence rates in arms B and C were similar, overall and among PLHIV. Among HIV-negative individuals, there were too few events for cross-arm comparisons. Study limitations include the use of self-report which may have been subject to under-reporting, limited covariate adjustment due to the small number of events, and high losses to follow-up over time.

CONCLUSIONS

In this study, community-wide UTT and TB screening resulted in substantially lower TB incidence among PLHIV at population-level, compared to standard-of-care, with statistical significance reached in the final study year. There was also some evidence this translated to a decrease in self-reported TB incidence overall in the population. Reduction in arm A but not B suggests UTT drove the observed effect. Our data support the role of UTT in TB control, in addition to HIV control, in high TB/HIV burden settings.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01900977.

The Burden of Bacteriologically Negative TB Diagnosis: A Four-Year Review of Tuberculosis Cases at a Tertiary Facility

Aim

We aimed to investigate the demographic and clinical factors associated with TB mortality in patients managed at a tertiary TB referral center.

Methods

We conducted a retrospective review of the medical records of 1,933 TB patients seen between January 2017 and December 2020 at the Korle-Bu Teaching Hospital (KBTH) Chest Department in Accra, Ghana. TB mortality was defined as any TB patient who died for any reason during the course of treatment. Multivariable logistic regression was used to estimate adjusted odds ratios with 95% confidence intervals for factors associated with TB mortality.

Results

A total of 1,933 patients with TB were registered at the chest clinic over the study period. Males accounted for 1,227 (63.5%), and majority of participants were between 24 and 64 years old. Pulmonary TB (PTB) and extrapulmonary TB (EPTB) cases accounted for 51% and 48.4% of the total TB cases, respectively. A significant proportion (69%) of the patients managed for TB had no bacteriological confirmation of the disease. About 34% of tested TB patients were HIV positive. Mortality among patients was 33.6%. In a multivariable regression model, patients with HIV positive status had over 3-fold increased risk of mortality, compared to those with HIV negative status. TB patients diagnosed empirically had an increased risk of death compared to those with a confirmed diagnosis.

Conclusion

The proportion of clinically diagnosed TB was high among the patients seen at the chest clinic. Mortality was high among the patients with HIV/TB coinfection as well as in patients with empirical TB diagnosis.

The tuberculous pleural effusion

Pleural tuberculosis (TB) is a common entity with similar epidemiological characteristics to pulmonary TB. It represents a spectrum of disease that can variably self-resolve or progress to TB empyema with severe sequelae such as chronic fibrothorax or empyema necessitans. Coexistence of and progression to pulmonary TB is high. Diagnosis is challenging, as pleural TB is paucibacillary in most cases, but every effort should be made to obtain microbiological diagnosis, especially where drug resistance is suspected. Much attention has been focussed on adjunctive investigations to support diagnosis, but clinicians must be aware that apparent diagnostic accuracy is affected both by the underlying TB prevalence in the population, and by the diagnostic standard against which the specified investigation is being evaluated. Pharmacological treatment of pleural TB is similar to that of pulmonary TB, but penetration of the pleural space may be suboptimal in complicated effusions. Evidence for routine drainage is limited, but evacuation of the pleural space is indicated in complicated disease.

Educational aims

To demonstrate that pleural TB incorporates a wide spectrum of disease, ranging from self-resolving lymphocytic effusions to severe TB empyema with serious sequelae.To emphasise the high coexistence of pulmonary TB with pleural TB, and the importance of obtaining sputum for culture (induced if necessary) in all cases.To explore the significant diagnostic challenges posed by pleural TB, and consequently the frequent lack of information about drug sensitivity prior to initiating treatment.To highlight the influence of underlying TB prevalence in the population on the diagnostic accuracy of adjunctive investigations for the diagnosis of pleural TB.To discuss concerns around penetration of anti-TB medications into the pleural space and how this can influence decisions around treatment duration in practice.

Unusual presentation of Pott disease and diagnostic challenges in a resource-limited setting: a case report

BACKGROUND

Pott disease is rare and responsible for only 1%-2% of all tuberculosis cases. It poses diagnostic challenges in resource-limited settings due to unusual presentation and limited investigative capacity, resulting in debilitating sequelae if diagnosed late.

CASE PRESENTATION

We present a case of severe Pott disease of the lumbar spine, with a large paravertebral abscess tracking down to the gluteal region in a 27-year-old Black African Ugandan woman living with human immunodeficiency virus, whose main complaint was right lower abdominal pain. She was initially misdiagnosed from the peripheral clinics as a case of lumbago and later with a psoas abscess. The diagnosis of severe Pott disease was established at the regional referral hospital following an abdominal computed tomography scan, and the patient was appropriately initiated on anti-tuberculosis drugs. However, only abscess drainage and provision of a lumbar corset were possible, with no neurosurgical intervention done on the spine due to financial constraints. Clinical review at 2, 6, and 12 months revealed improvement.

CONCLUSIONS

Pott disease may present with non-specific symptoms such as abdominal pain resulting from pressure effects of an expansile cold abscess. This, coupled with limited diagnostic capacity in resource-limited settings; results in significant morbidity and possible mortality. Hence, there is need to train clinicians to increase their index of suspicion and equip health units with basic radiological equipment, such as x-ray, for timely detection and subsequent management of Pott disease.

Sex and Gender Differences in Tuberculosis Pathogenesis and Treatment Outcomes

Tuberculosis remains a daunting public health concern in many countries of the world. A consistent observation in the global epidemiology of tuberculosis is an excess of cases of active pulmonary tuberculosis among males compared with females. Data from both humans and animals also suggest that males are more susceptible than females to develop active pulmonary disease. Similarly, male sex has been associated with poor treatment outcomes. Despite this growing body of evidence, little is known about the mechanisms driving sex bias in tuberculosis disease. Two dominant hypotheses have been proposed to explain the predominance of active pulmonary tuberculosis among males. The first is based on the contribution of biological factors, such as sex hormones and genetic factors, on host immunity during tuberculosis. The second is focused on non-biological factors such as smoking, professional exposure, and health-seeking behaviors, known to be influenced by gender. In this chapter, we review the literature regarding these two prevailing hypotheses by presenting human but also experimental animal studies. In addition, we presented studies aiming at examining the impact of sex and gender on other clinical forms of tuberculosis such as latent tuberculosis infection and extrapulmonary tuberculosis, which both appear to have their own specificities in relation to sex. We also highlighted potential intersections between sex and gender in the context of tuberculosis and shared future directions that could guide in elucidating mechanisms of sex-based differences in tuberculosis pathogenesis and treatment outcomes.

Pleural Tuberculosis

Pleural tuberculosis (TB) is common and often follows a benign course but may result in serious long-term morbidity. Diagnosis is challenging because of the paucibacillary nature of the condition. Advances in Mycobacterium culture media and PCR-based techniques have increased the yield from mycobacteriologic tests. Surrogate biomarkers perform well in diagnostic accuracy studies but must be interpreted in the context of the pretest probability in the individual patient. Confirming the diagnosis often requires biopsy, which may be acquired through thoracoscopy or image-guided closed pleural biopsy. Treatment is standard anti-TB therapy, with optional drainage and intrapleural fibrinolytics or surgery in complicated cases.

Ocular Tuberculosis in HIV-infected Individuals

Aim: To review the current literature and publications to assess the clinical features, recommended investigations and treatment for ocular tuberculosis in HIV infected patients. Methods: Literature review. Results: The human immunodeficiency virus (HIV) epidemic affects as many as 37.9 million people. Mycobacterium tuberculosis infection is common in HIV infection and is a leading cause of death and morbidity. Common clinical presentations include anterior uveitis (granulomatous or otherwise), choroidal granulomas/tubercles, chorioretinitis, subretinal abscess, panophthalmitis, retinal detachment and vasculitis. The majority of clinical findings were in the posterior segment, appeared primarily infective (tubercles/chorioretinitis/abscess) and were largely seen in the context of pulmonary tuberculosis or disseminated disease. Current investigational patterns include corroborative tests such as tuberculin skin test or Interferon-γ release assay. Systemic testing includes Computed Tomography, MRI or PET/CT scans. Newer Molecular techniques such as GeneXpert MTB/RIF assay and Line Probe assays (LPA) are increasingly important. Apart from standard ocular anti-inflammatory protocols, anti-tubercular treatment as per the clinical staging (latent or active) needs to be initiated. Initiation of anti-retroviral therapy (ART) is important and can be started soon after ATT. Conclusions: Ocular manifestations within this group are distinct and unique investigational and therapeutic approaches are needed.

Machine learning reveals that Mycobacterium tuberculosis genotypes and anatomic disease site impacts drug resistance and disease transmission among patients with proven extra-pulmonary tuberculosis

Background

There is a general dearth of information on extrapulmonary tuberculosis (EPTB). Here, we investigated Mycobacterium tuberculosis (Mtb) drug resistance and transmission patterns in EPTB patients treated in the Tshwane metropolitan area, in South Africa.

Methods

Consecutive Mtb culture-positive non-pulmonary samples from unique EPTB patients underwent mycobacterial genotyping and were assigned to phylogenetic lineages and transmission clusters based on spoligotypes. MTBDRplus assay was used to search mutations for isoniazid and rifampin resistance. Machine learning algorithms were used to identify clinically meaningful patterns in data. We computed odds ratio (OR), attributable risk (AR) and corresponding 95% confidence intervals (CI).

Results

Of the 70 isolates examined, the largest cluster comprised 25 (36%) Mtb strains that belonged to the East Asian lineage. East Asian lineage was significantly more likely to occur within chains of transmission when compared to the Euro-American and East-African Indian lineages: OR = 10.11 (95% CI: 1.56–116). Lymphadenitis, meningitis and cutaneous TB, were significantly more likely to be associated with drug resistance: OR = 12.69 (95% CI: 1.82–141.60) and AR = 0.25 (95% CI: 0.06–0.43) when compared with other EPTB sites, which suggests that poor rifampin penetration might be a contributing factor.

Conclusions

The majority of Mtb strains circulating in the Tshwane metropolis belongs to East Asian, Euro-American and East-African Indian lineages. Each of these are likely to be clustered, suggesting on-going EPTB transmission. Since 25% of the drug resistance was attributable to sanctuary EPTB sites notorious for poor rifampin penetration, we hypothesize that poor anti-tuberculosis drug dosing might have a role in the development of resistance.

The Changing Global Epidemic of HIV and Ocular Disease

Purpose: Overview of the evolving epidemiology of human immunodeficiency virus (HIV)-related ocular disease over time. Method: Narrative review. Results: HIV enhances susceptibility to opportunistic eye infections, has direct pathogenic effects, and places patients at risk of immune recovery inflammatory syndromes in previously infected eyes after starting highly-active antiretroviral therapy (HAART). Widespread availability of HAART has resulted in a decrease of infectious ocular conditions such as cytomegalovirus retinitis, toxoplasmic retinitis, squamous cell carcinoma of the conjunctiva, and microvascular retinopathy. However, large coexisting burdens of tuberculosis, herpesvirus infection and syphilis (among others) continue to contribute to the burden of ocular disease, especially in low-resource settings. Growing risks of cataract, retinopathy and retinal nerve fiber thinning can affect patients with chronic HIV on HAART; thought due to chronic inflammation and immune activation. Conclusion: The changing epidemic of ocular disease in HIV-infected patients warrants close monitoring and identification of interventions that can help reduce the imminent burden of disease.

Imaging and clinical features of breast tuberculosis: a review series of 62 cases

AIM

To outline the disease burden of breast tuberculosis (TB) as a quantitative analysis amongst three tertiary hospitals in South Africa, with correlation to their clinical, demographic, and imaging features.

MATERIALS AND METHODS

A retrospective analysis was undertaken over an 18-month period (01/01/2017-30/06/2018) of all patients undergoing laboratory investigations for breast disease at the mammography departments of these three tertiary centres.

RESULTS

The prevalence of breast TB was 2.5% (n=62) of 2,516 patients. The median age of presentation was 38.5 years (interquartile range [IQR] 33-45). HIV status was known in 45 patients, of whom 36 were HIV infected (80%, 95% CI: 0.65-0.90, p<0.0001). Based on the ultrasound and/or mammogram findings, the patients were classified into five categories: TB breast abscess (40.3%), inflammatory/disseminated (24.2%), isolated TB lymphadenitis (22.6%), nodular (11.3%), and sclerosing form (1.6%). Histology demonstrated necrotising granulomatous inflammation in 57 cases (92%). Acid-fast bacilli (AFB) were positive in 8.1% (n=5) of the cytology and 16.1% (n=10) of the histology specimens. Culture for Mycobacterium tuberculosis was positive in 27% (17 cases), and in 12.9% (n=8). AFB were detected histologically using polymerase chain reaction (PCR) testing.

CONCLUSION

Knowledge of the varied clinical and radiological features is necessary to maintain a high degree of suspicion to prevent misdiagnoses, inappropriate management, and complications. Ultrasound-guided core biopsy rather than fine-needle aspiration (FNA) is advocated as the first-line intervention in diagnosing or excluding this disease, as it yields a better tissue sample and more often a positive diagnosis.

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.

Child and adult spinal tuberculosis at tertiary hospitals in the Western Cape, South Africa: 4-year burden and trend

The aim of this retrospective review was to assess the overall burden and trend in spinal tuberculosis (TB) at tertiary hospitals in the Western Cape Province of South Africa. All spinal TB cases seen at the province's three tertiary hospitals between 2012 and 2015 were identified and clinical records of each case assessed. Cases were subsequently classified as bacteriologically confirmed or clinically diagnosed and reported with accompanying clinical and demographic information. Odds ratios (OR) for severe spinal disease and corrective surgery in child vs. adult cases were calculated. A total of 393 cases were identified (319 adults, 74 children), of which 283 (72%) were bacteriologically confirmed. Adult cases decreased year-on-year (P = 0.04), however there was no clear trend in child cases. Kyphosis was present in 60/74 (81%) children and 243/315 (77%) adults with available imaging. Corrective spinal surgery was performed in 35/74 (47%) children and 80/319 (25%) adults (OR 2.7, 95% confidence interval 1.6-4.5, P = 0.0003). These findings suggest that Western Cape tertiary hospitals have experienced a substantial burden of spinal TB cases in recent years with a high proportion of severe presentation, particularly among children. Spinal TB remains a public health concern with increased vigilance required for earlier diagnosis, especially of child cases.