Plasma Indoleamine 2, 3-Dioxygenase, a Biomarker for Tuberculosis in Human Immunodeficiency Virus-Infected Patients

Background

There is no biomarker for diagnosing active tuberculosis in patients with human immunodeficiency virus (HIV) infection. Indoleamine 2, 3-dioxygenase (IDO) is an immunoregulatory enzyme that breaks down tryptophan (Trp) to metabolites known as kynurenines (Kyns). We investigated whether IDO activity, as measured by the ratio of Kyn to Trp, could be used to diagnose or predict active tuberculosis disease in HIV-infected adults.

Methods

Kyn and Trp concentrations were measured using ultraperformance liquid chromatography mass spectrometry in plasma samples from 32 HIV-infected patients in whom active tuberculosis developed and who were followed up prospectively. We compared to 70 HIV-infected control subjects from the same cohort in whom tuberculosis did not develop, matched by age, sex, and CD4 cell count, and 37 unmatched HIV-infected patients with a diagnosis of pneumonia. Clinical parameters, including body mass index, CD4 cell count, HIV load, and C-reactive protein levels were analyzed.

Results

At the time of tuberculosis diagnosis, IDO activity was significantly higher in patients with tuberculosis than in controls (P < .001). Six months before tuberculosis diagnosis, IDO activity was significantly higher in all patients who later developed tuberculosis (P < .001) than controls. After 6 months of tuberculosis treatment, IDO activity in patients with tuberculosis declined to levels similar to those in controls. IDO activity was 4-fold higher in patients with tuberculosis than in those with pneumonia, and could be used to distinguish them. With a receiver operating characteristic curve, IDO activity had a sensitivity of 97%, a specificity of 99%, and positive and negative predictive values of 89% and 100% for detecting active tuberculosis disease.

Conclusion

Plasma IDO activity is suitable as a biomarker of active tuberculosis in HIV-positive patients.

Impact of Antiretroviral Therapy on Liver Fibrosis Among Human Immunodeficiency Virus-Infected Adults With and Without HBV Coinfection in Zambia

Background

We investigated changes in hepatic fibrosis, based on transient elastography (TE), among human immunodeficiency virus (HIV)-infected patients with and without hepatitis B virus (HBV) coinfection on antiretroviral therapy (ART) in Zambia.

Methods

Patients' liver stiffness measurements (LSM; kiloPascals [kPa]) at ART initiation were categorized as no or minimal fibrosis (equivalent to Metavir F0-F1), significant fibrosis (F2-F3), and cirrhosis (F4). TE was repeated following 1 year of ART. Stratified by HBV coinfection status (hepatitis B surface antigen positive at baseline), we described LSM change and the proportion with an increase/decrease in fibrosis category. Using multivariable logistic regression, we assessed correlates of significant fibrosis/cirrhosis at 1 year on ART.

Results

Among 463 patients analyzed (61 with HBV coinfection), median age was 35 years, 53.7% were women, and median baseline CD4+ count was 240 cells/mm3. Nearly all (97.6%) patients received tenofovir disoproxil fumarate-containing ART, in line with nationally recommended first-line treatment. The median LSM change was -0.70 kPa (95% confidence interval, -3.0 to +1.7) and was similar with and without HBV coinfection. Significant fibrosis/cirrhosis decreased in frequency from 14.0% to 6.7% (P < .001). Increased age, male sex, and HBV coinfection predicted significant fibrosis/cirrhosis at 1 year (all P < .05).

Conclusion

The percentage of HIV-infected Zambian adults with elevated liver stiffness suggestive of significant fibrosis/cirrhosis decreased following ART initiation-regardless of HBV status. This suggests that HIV infection plays a role in liver inflammation. HBV-coinfected patients were more likely to have significant fibrosis/cirrhosis at 1 year on ART.

Clinical Trials Registration

NCT02060162.

Depression and alcohol use disorder at antiretroviral therapy initiation led to disengagement from care in South Africa

We sought to assess mental health at the time of antiretroviral therapy (ART) initiation and subsequent retention in care over a six-month follow-up period. A total of 136 people living with HIV in South Africa were administered surveys measuring demographic information and mental health indicators at the time of ART initiation. Follow-up was completed via chart abstraction to assess for six-month outcomes of retention in care and viral suppression. At enrollment, 45/136 (33%), 67/136 (49%), and 45/136 (33%) participants screened positive for depression, anxiety, and alcohol use disorder, respectively. After six months of follow-up, 96/136 (71%) participants remained in care; 35/87 (40.2%) participants who remained in care had a level <50 copies/mL. Those with depression (49% vs. 77% retained; p < 0.01) and those with alcohol use disorder (52% vs. 76% retained; p < 0.01) were less likely to be retained in care. In multivariable logistic regression, depression OR 3.46 (95% CI: 1.33, 7.97; p < 0.01) and alcohol abuse OR 3.89 (95% CI: 1.70, 8.97; p < 0.01) were independently associated with loss from care. These results emphasize the importance of mental health on early ART outcomes and the HIV care continuum.

Factors associated with pulmonary impairment in HIV-infected South African adults

Background

HIV-infected individuals have increased risk of developing obstructive lung disease (OLD). Studies from developed countries report high viral load, low CD4 counts, and anti-retroviral therapy (ART) to be associated with OLD; but these findings may not be generalizable to populations in resource-limited settings.

Methods

We conducted a prospective cohort study of lung function in 730 HIV-infected black South African adults. Pre-bronchodilator spirometry was performed at enrollment and repeated annually for three years. Logistic regression models were used to identify factors associated with OLD, defined as FEV1/FVC<0.70, at enrollment. Excess annual declines in FEV1 and FVC were modelled as the product-term of follow-up time and exposures using random effects regression.

Results

Median (IQR) age at enrollment was 36 (32–41) years, 85% were female and 30% ever-smoked with a median (IQR) exposure of 3 (1–6) pack-years. Median (IQR) CD4 count and viral load at enrollment were 372 (261–518) cells/mm³ and 2655 (91–13,548) copies/mL respectively. Overall, 25% were receiving ART at enrollment, 16% of whom reported at least 6 months of ART receipt. OLD was found in 35 (5%) at enrollment. Increasing age (aOR = 2.08 per 10-years [95%CI 1.22–3.57], p = 0.007), current smoking (aOR = 3.55 [95%CI 1.20–10.53], p = 0.02), and CRP (aOR = 1.01 per unit-increase [95%CI 1.00–1.03], p = 0.04) were significantly associated with OLD at enrollment; while increasing CD4 count (aOR = 1.02 per-100 cells/mm³ [95%CI 0.85–1.22], p = 0.82), viral load (aOR = 0.67 per log-increase [95%CI 0.43–1.10], p = 0.12) and receipt of ART (aOR = 0.57 [95%CI 0.18–1.75], p = 0.32) were not. The median (IQR) follow-up time was 18 (12–24) months. Participants with a history of tuberculosis (TB) had a 35 mL (95%CI 2–68, p = 0.03) and 57 mL (95%CI 19–96, p = 0.003) per year excess loss of FEV1 and FVC respectively.

Conclusion

Prevalent OLD was associated with older age, current smoking and higher CRP levels, but not CD4 counts and ART, in HIV-infected South African adults. Better understanding of the long-term effects of TB, smoking and inflammation on lung function in HIV-infected populations is urgently needed.

Mutational Correlates of Virological Failure in Individuals Receiving a WHO-Recommended Tenofovir-Containing First-Line Regimen: An International Collaboration

Tenofovir disoproxil fumarate (TDF) genotypic resistance defined by K65R/N and/or K70E/Q/G occurs in 20% to 60% of individuals with virological failure (VF) on a WHO-recommended TDF-containing first-line regimen. However, the full spectrum of reverse transcriptase (RT) mutations selected in individuals with VF on such a regimen is not known. To identify TDF regimen-associated mutations (TRAMs), we compared the proportion of each RT mutation in 2873 individuals with VF on a WHO-recommended first-line TDF-containing regimen to its proportion in a cohort of 50,803 antiretroviral-naïve individuals. To identify TRAMs specifically associated with TDF-selection pressure, we compared the proportion of each TRAM to its proportion in a cohort of 5805 individuals with VF on a first-line thymidine analog-containing regimen. We identified 83 TRAMs including 33 NRTI-associated, 40 NNRTI-associated, and 10 uncommon mutations of uncertain provenance. Of the 33 NRTI-associated TRAMs, 12 - A62V, K65R/N, S68G/N/D, K70E/Q/T, L74I, V75L, and Y115F - were more common among individuals receiving a first-line TDF-containing compared to a first-line thymidine analog-containing regimen. These 12 TDF-selected TRAMs will be important for monitoring TDF-associated transmitted drug-resistance and for determining the extent of reduced TDF susceptibility in individuals with VF on a TDF-containing regimen.

Occult HIV-1 drug resistance to thymidine analogues following failure of first-line tenofovir combined with a cytosine analogue and nevirapine or efavirenz in sub Saharan Africa: a retrospective multi-centre cohort study

Background

HIV-1 drug resistance to older thymidine analogue nucleoside reverse transcriptase inhibitor drugs has been identified in sub-Saharan Africa in patients with virological failure of first-line combination antiretroviral therapy (ART) containing the modern nucleoside reverse transcriptase inhibitor tenofovir. We aimed to investigate the prevalence and correlates of thymidine analogue mutations (TAM) in patients with virological failure of first-line tenofovir-containing ART.

Methods

We retrospectively analysed patients from 20 studies within the TenoRes collaboration who had locally defined viral failure on first-line therapy with tenofovir plus a cytosine analogue (lamivudine or emtricitabine) plus a non-nucleoside reverse transcriptase inhibitor (NNRTI; nevirapine or efavirenz) in sub-Saharan Africa. Baseline visits in these studies occurred between 2005 and 2013. To assess between-study and within-study associations, we used meta-regression and meta-analyses to compare patients with and without TAMs for the presence of resistance to tenofovir, cytosine analogue, or NNRTIs.

Findings

Of 712 individuals with failure of first-line tenofovir-containing regimens, 115 (16%) had at least one TAM. In crude comparisons, patients with TAMs had lower CD4 counts at treatment initiation than did patients without TAMs (60·5 cells per μL [IQR 21·0–128·0] in patients with TAMS vs 95·0 cells per μL [37·0–177·0] in patients without TAMs; p=0·007) and were more likely to have tenofovir resistance (93 [81%] of 115 patients with TAMs vs 352 [59%] of 597 patients without TAMs; p<0·0001), NNRTI resistance (107 [93%] vs 462 [77%]; p<0·0001), and cytosine analogue resistance (100 [87%] vs 378 [63%]; p=0·0002). We detected associations between TAMs and drug resistance mutations both between and within studies; the correlation between the study-level proportion of patients with tenofovir resistance and TAMs was 0·64 (p<0·0001), and the odds ratio for tenofovir resistance comparing patients with and without TAMs was 1·29 (1·13–1·47; p<0·0001)

Interpretation

TAMs are common in patients who have failure of first-line tenofovir-containing regimens in sub-Saharan Africa, and are associated with multidrug resistant HIV-1. Effective viral load monitoring and point-of-care resistance tests could help to mitigate the emergence and spread of such strains.

Chronic hepatitis B increases mortality and complexity among HIV-coinfected patients in South Africa: a cohort study

OBJECTIVES

To assess the effect of chronic hepatitis B on survival and clinical complexity among people living with HIV following antiretroviral therapy (ART) initiation.

METHODS

We evaluated mortality and single-drug substitutions up to 3 years from ART initiation (median follow-up 2.75 years; interquartile range 2-3 years) among patients with and without chronic hepatitis B (CHB) enrolled in a workplace HIV care programme in South Africa.

RESULTS

Mortality was increased for CHB patients with hepatitis B virus (HBV) DNA levels > 10 000 copies/mL (adjusted hazard ratio 3.1; 95% confidence interval 1.2-8.0) compared with non-CHB patients. We did not observe a similar difference between non-CHB patients and those with CHB and HBV DNA < 10 000 copies/mL (adjusted hazard ratio 0.70; 95% confidence interval 0.2-2.3). Single-drug substitutions occurred more frequently among coinfected patients regardless of HBV DNA level.

CONCLUSIONS

Our findings suggest that CHB may increase mortality and complicate ART management.

HIV and tuberculosis in prisons in sub-Saharan Africa

Given the dual epidemics of HIV and tuberculosis in sub-Saharan Africa and evidence suggesting a disproportionate burden of these diseases among detainees in the region, we aimed to investigate the epidemiology of HIV and tuberculosis in prison populations, describe services available and challenges to service delivery, and identify priority areas for programmatically relevant research in sub-Saharan African prisons. To this end, we reviewed literature on HIV and tuberculosis in sub-Saharan African prisons published between 2011 and 2015, and identified data from only 24 of the 49 countries in the region. Where data were available, they were frequently of poor quality and rarely nationally representative. Prevalence of HIV infection ranged from 2·3% to 34·9%, and of tuberculosis from 0·4 to 16·3%; detainees nearly always had a higher prevalence of both diseases than did the non-incarcerated population in the same country. We identified barriers to prevention, treatment, and care services in published work and through five case studies of prison health policies and services in Zambia, South Africa, Malawi, Nigeria, and Benin. These barriers included severe financial and human-resource limitations and fragmented referral systems that prevent continuity of care when detainees cycle into and out of prison, or move between prisons. These challenges are set against the backdrop of weak health and criminal-justice systems, high rates of pre-trial detention, and overcrowding. A few examples of promising practices exist, including routine voluntary testing for HIV and screening for tuberculosis upon entry to South African and the largest Zambian prisons, reforms to pre-trial detention in South Africa, integration of mental health services into a health package in selected Malawian prisons, and task sharing to include detainees in care provision through peer-educator programmes in Rwanda, Zimbabwe, Zambia, and South Africa. However, substantial additional investments are required throughout sub-Saharan Africa to develop country-level policy guidance, build human-resource capacity, and strengthen prison health systems to ensure universal access to HIV and tuberculsosis prevention, treatment, and care of a standard that meets international goals and human rights obligations.

A Framework to Inform Strategies to Improve the HIV Care Continuum in Low- and Middle-Income Countries

Reasons for attrition along the HIV care continuum are well described. However, improving patient engagement in care has been a challenge. New approaches to understanding and responding to reasons for attrition are required. Here, with a focus on low- and middle-income countries, we propose a framework that brings together an explanatory model with social ecological levels. Individual action may be based on a conscious or unconscious balance between perceived value and perceived costs. When the balance between value and cost favors value, engagement in care can be expected. Value and cost may be mediated by levels of the individual, interpersonal interactions, the clinic experience, community, society, and policy. We encourage the use of a framework for developing strategies to improve the care continuum and believe that this framework provides a rigorous approach.

Household HIV Testing Uptake among Contacts of TB Patients in South Africa

BACKGROUND

In high HIV prevalence settings, offering HIV testing may be a reasonable part of contact tracing of index tuberculosis (TB) patients. We evaluated the uptake of HIV counselling and testing (HCT) among household contacts of index TB patients and the proportion of newly diagnosed HIV-infected persons linked into care as part of a household TB contact tracing study.

METHODS

We recruited index TB patients at public health clinics in two South African provinces to obtain consent for household contact tracing. During scheduled household visits we offered TB symptom screening to all household members and HCT to individuals ≥14years of age. Factors associated with HCT uptake were investigated using a random effects logistic regression model.

RESULTS & DISCUSSION

Out of 1,887 listed household members ≥14 years old, 984 (52%) were available during a household visit and offered HCT of which 108 (11%) self-reported being HIV infected and did not undergo HCT. Of the remaining 876, a total of 304 agreed to HCT (35%); 26 (8.6%) were newly diagnosed as HIV positive. In multivariable analysis, factors associated with uptake of HCT were prior testing (odds ratio 1.6; 95% confidence interval [CI]: 1.1-2.3) and another member in the household testing (odds ratio 2.4; 95% CI: 1.7-3.4). Within 3 months of testing HIV-positive, 35% reported initiating HIV care.

CONCLUSION

HCT as a component of household TB contact tracing reached individuals without prior HIV testing, however uptake of HIV testing was poor. Strategies to improve HIV testing in household contacts should be evaluated.

[S2k-guideline Helicobacter pylori and gastroduodenal ulcer disease]

In the line "bismuth-containing quadruple therapy" of Table 7 (p 342), in the column "dosage" incorrectly at the three antibiotics respectively 1-1-1-1. The correct is: 3-3-3-3.

Hepatitis B Infection, Viral Load and Resistance in HIV-Infected Patients in Mozambique and Zambia

Background

Few data on the virological determinants of hepatitis B virus (HBV) infection are available from southern Africa.

Methods

We enrolled consecutive HIV-infected adult patients initiating antiretroviral therapy (ART) at two urban clinics in Zambia and four rural clinics in Northern Mozambique between May 2013 and August 2014. HBsAg screening was performed using the Determine^® rapid test. Quantitative real-time PCR and HBV sequencing were performed in HBsAg-positive patients. Risk factors for HBV infection were evaluated using Chi-square and Mann-Whitney tests and associations between baseline characteristics and high level HBV replication explored in multivariable logistic regression.

Results

Seventy-eight of 1,032 participants in Mozambique (7.6%, 95% confidence interval [CI]: 6.1–9.3) and 90 of 797 in Zambia (11.3%, 95% CI: 9.3–13.4) were HBsAg-positive. HBsAg-positive individuals were less likely to be female compared to HBsAg-negative ones (52.3% vs. 66.1%, p<0.001). Among 156 (92.9%) HBsAg-positive patients with an available measurement, median HBV viral load was 13,645 IU/mL (interquartile range: 192–8,617,488 IU/mL) and 77 (49.4%) had high values (>20,000 UI/mL). HBsAg-positive individuals had higher levels of ALT and AST compared to HBsAg-negative ones (both p<0.001). In multivariable analyses, male sex (adjusted odds ratio: 2.59, 95% CI: 1.22–5.53) and CD4 cell count below 200/μl (2.58, 1.20–5.54) were associated with high HBV DNA. HBV genotypes A1 (58.8%) and E (38.2%) were most prevalent. Four patients had probable resistance to lamivudine and/or entecavir.

Conclusion

One half of HBsAg-positive patients demonstrated high HBV viremia, supporting the early initiation of tenofovir-containing ART in HIV/HBV-coinfected adults.

Hepatitis B prevalence and treatment needs among Tibetan refugees residing in India

Untreated chronic hepatitis B can lead to liver failure and/or liver cancer. These complications can be avoided through prevention with vaccination or treatment of disease. To inform health policy for the Tibetan community in India, we conducted study of hepatitis B prevalence and treatment needs. We conducted a cross-sectional study over 3 months of 2013. Households were randomly selected for participation via a satellite map; one boarding school and one residential monastery were also included. Participants were asked questions and a whole blood sample was collected for HBsAg assay. Participants with a positive HBsAg result were tested for hepatitis B e antigen, ALT, and AST. Participants with a negative HBsAg result were tested for anti-hepatitis B core antibodies. We recruited 2,769 participants; of which 247 (8.9%) were positive for HBsAg. Participants more likely to have a positive HBsAg result were those born in Tibet (12.4%) and aged 30-59 years old. Of those with a positive HBsAg result, 60.7% were positive for hepatitis B e antigen 7% of whom fit into a likely treatment-needed category; the others fit into management categories requiring repeat ALT testing with or without liver fibrosis assessment. Among participants negative for HBsAg, 52.9% from household sampling had anti-HBc antibodies. We identified a high endemicity of chronic hepatitis B in a Tibetan community in India. Resource appropriate approaches are needed for managing chronic hepatitis B in settings such as this one. J. Med. Virol. 88:1357-1363, 2016. © 2016 Wiley Periodicals, Inc.

Implementation and Operational Research: Risk Charts to Guide Targeted HIV-1 Viral Load Monitoring of ART: Development and Validation in Patients From Resource-Limited Settings

BACKGROUND

HIV-1 RNA viral load (VL) testing is recommended to monitor antiretroviral therapy (ART) but not available in many resource-limited settings. We developed and validated CD4-based risk charts to guide targeted VL testing.

METHODS

We modeled the probability of virologic failure up to 5 years of ART based on current and baseline CD4 counts, developed decision rules for targeted VL testing of 10%, 20%, or 40% of patients in 7 cohorts of patients starting ART in South Africa, and plotted cutoffs for VL testing on colour-coded risk charts. We assessed the accuracy of risk chart-guided VL testing to detect virologic failure in validation cohorts from South Africa, Zambia, and the Asia-Pacific.

RESULTS

In total, 31,450 adult patients were included in the derivation and 25,294 patients in the validation cohorts. Positive predictive values increased with the percentage of patients tested: from 79% (10% tested) to 98% (40% tested) in the South African cohort, from 64% to 93% in the Zambian cohort, and from 73% to 96% in the Asia-Pacific cohort. Corresponding increases in sensitivity were from 35% to 68% in South Africa, from 55% to 82% in Zambia, and from 37% to 71% in Asia-Pacific. The area under the receiver operating curve increased from 0.75 to 0.91 in South Africa, from 0.76 to 0.91 in Zambia, and from 0.77 to 0.92 in Asia-Pacific.

CONCLUSIONS

CD4-based risk charts with optimal cutoffs for targeted VL testing maybe useful to monitor ART in settings where VL capacity is limited.

Treatment Failure, Drug Resistance, and CD4 T-Cell Count Decline Among Postpartum Women on Antiretroviral Therapy in South Africa

BACKGROUND

We assessed HIV RNA suppression, resistance, and CD4 T-cell count 12 months postpartum among pregnant women retained in care in an observational cohort study.

METHODS

We prospectively followed two groups of HIV-infected pregnant women--with or without tuberculosis--recruited from prenatal clinics in South Africa. Women who received antiretroviral therapy during pregnancy and reported being on therapy 12 months postpartum were included. Serum samples from women with HIV viremia 12 months postpartum were tested for drug resistance.

RESULTS

Of 103 women in the study, median age and CD4 T-cell count at enrollment were 29 years [interquartile range (IQR): 26-32] and 317 cells per cubic millimeter (IQR: 218-385), respectively; 43 (42%) had tuberculosis at baseline. During pregnancy, 87% of the women achieved an HIV RNA <400 copies per milliliter compared with 71% at 12 months postpartum (P < 0.001). Factors independently associated with an HIV RNA <400 copies per milliliter at 12 months were age ≥ 30 years, detectable plasma efavirenz concentration, and HIV RNA <400 copies per milliliter while pregnant; there was a trend toward both a detectable viral load and peripartum depression. HIV drug resistance results were available from 25 women, and 12 (48%) had major drug resistance mutations. CD4 T-cell count declined a median of 13 cells per cubic millimeter (IQR: -66 to 140) from delivery to 12 months in women with viremia at 12 months.

CONCLUSIONS

Success with maintaining virologic control declined postpartum among HIV-infected women who remained in care and on antiretroviral therapy, and CD4 T-cell count decline and drug resistance were common.

CD4 count-based failure criteria combined with viral load monitoring may trigger worse switch decisions than viral load monitoring alone

OBJECTIVE

CD4 count decline often triggers antiretroviral regimen switches in resource-limited settings, even when viral load testing is available. We therefore compared CD4 failure and CD4 trends in patients with viraemia with or without antiretroviral resistance.

METHODS

Retrospective cohort study investigating the association of HIV drug resistance with CD4 failure or CD4 trends in patients on first-line antiretroviral regimens during viraemia. Patients with viraemia (HIV RNA >1000 copies/ml) from two HIV treatment programmes in South Africa (n = 350) were included. We investigated the association of M184V and NNRTI resistance with WHO immunological failure criteria and CD4 count trends, using chi-square tests and linear mixed models.

RESULTS

Fewer patients with the M184V mutation reached immunologic failure criteria than those without: 51 of 151(34%) vs. 90 of 199 (45%) (P = 0.03). Similarly, 79 of 220 (36%) patients, who had major NNRTI resistance, had immunological failure, whereas 62 of 130 (48%) without (chi-square P = 0.03) did. The CD4 count decline among patients with the M184V mutation was 2.5 cells/mm(3) /year, whereas in those without M184V it was 14 cells/mm(3) /year (P = 0.1), but the difference in CD4 count decline with and without NNRTI resistance was marginal.

CONCLUSION

Our data suggest that CD4 count monitoring may lead to inappropriate delayed therapy switches for patients with HIV drug resistance. Conversely, patients with viraemia but no drug resistance are more likely to have a CD4 count decline and thus may be more likely to be switched to a second-line regimen.

Pooling sputum from multiple individuals for Xpert® MTB/RIF testing: a strategy for screening high-risk populations

SETTING

Symptom-based screening for tuberculosis (TB) disease is limited by poor performance of symptom screening in several key populations. We tested the hypothesis that pooling sputum from multiple individuals for Xpert(®) MTB/RIF testing would reduce the number of tests required while retaining an acceptable sensitivity, thus allowing the use of Xpert for TB screening.

METHODS

We compared pooling ratios that would require the least number of assays using Xpert and determined that for a population with a TB prevalence of approximately 3%, a 1:5 pooling ratio is optimal. To evaluate sensitivity, we generated pools of one specimen with known Mycobacterium tuberculosis culture positivity (smear microscopy-positive or -negative) with four culture-negative specimens.

RESULTS

All 20 of the pools generated from a smear- and culture-positive sputum sample were positive using Xpert. Of the 22 pools with a smear-negative, culture-positive sample, we included 17 in the analysis, of which 13 (76%) were Xpert-positive.

CONCLUSIONS

Pooling of sputum samples using Xpert achieved reasonable sensitivity and warrants further evaluation of the systematic screening of high TB prevalence populations.

Monitoring and switching of first-line antiretroviral therapy in adult treatment cohorts in sub-Saharan Africa: collaborative analysis

BACKGROUND

HIV-1 viral load testing is recommended to monitor antiretroviral therapy (ART) but is not universally available. The aim of our study was to assess monitoring of first-line ART and switching to second-line ART in sub-Saharan Africa.

METHODS

We did a collaborative analysis of cohort studies from 16 countries in east Africa, southern Africa, and west Africa that participate in the international epidemiological database to evaluate AIDS (IeDEA). We included adults infected with HIV-1 who started combination ART between January, 2004, and January, 2013. We defined switching of ART as a change from a non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen to one including a protease inhibitor, with adjustment of one or more nucleoside reverse-transcriptase inhibitors (NRTIs). Virological and immunological failures were defined according to WHO criteria. We calculated cumulative probabilities of switching and hazard ratios with 95% CIs comparing routine viral load monitoring, targeted viral load monitoring, CD4 monitoring, and clinical monitoring, adjusting for programme and individual characteristics.

FINDINGS

Of 297,825 eligible patients, 10,352 (3%) switched to second-line ART during 782 ,412 person-years of follow-up. Compared with CD4 monitoring, hazard ratios for switching were 3·15 (95% CI 2·92-3·40) for routine viral load monitoring, 1·21 (1·13-1·30) for targeted viral load monitoring, and 0·49 (0·43-0·56) for clinical monitoring. Of 6450 patients with confirmed virological failure, 58·0% (95% CI 56·5-59·6) switched by 2 years, and of 15,892 patients with confirmed immunological failure, 19·3% (18·5-20·0) switched by 2 years. Of 10,352 patients who switched, evidence of treatment failure based on one CD4 count or viral load measurement ranged from 86 (32%) of 268 patients with clinical monitoring to 3754 (84%) of 4452 with targeted viral load monitoring. Median CD4 counts at switching were 215 cells per μL (IQR 117-335) with routine viral load monitoring, but were lower with other types of monitoring (range 114-133 cells per μL).

INTERPRETATION

Overall, few patients switched to second-line ART and switching happened late in the absence of routine viral load monitoring. Switching was more common and happened earlier after initiation of ART with targeted or routine viral load testing.

FUNDING

National Institute of Allergy and Infectious Diseases, Swiss National Science Foundation.

Evaluation of a point-of-care tuberculosis test-and-treat algorithm on early mortality in people with HIV accessing antiretroviral therapy (TB Fast Track study): study protocol for a cluster randomised controlled trial

Background

Early mortality for HIV-positive people starting antiretroviral therapy (ART) remains high in resource-limited settings, with tuberculosis the most important cause. Existing rapid diagnostic tests for tuberculosis lack sensitivity among HIV-positive people, and consequently, tuberculosis treatment is either delayed or started empirically (without bacteriological confirmation). We developed a management algorithm for ambulatory HIV-positive people, based on body mass index and point-of-care tests for haemoglobin and urine lipoarabinomannan (LAM), to identify those at high risk of tuberculosis and mortality. We designed a clinical trial to test whether implementation of this algorithm reduces six-month mortality among HIV-positive people with advanced immunosuppression.

Methods/design

The TB Fast Track study is an open, pragmatic, cluster randomised superiority trial, with 24 primary health clinics randomised to implement the intervention or standard of care. Adults (aged ≥18 years) with a CD4 count of 150 cells/μL or less, who have not received any tuberculosis treatment in the last three months, or ART in the last six months, are eligible. In intervention clinics, the study algorithm is used to classify individuals as at high, medium or low probability of tuberculosis. Those classified as high probability start tuberculosis treatment immediately, followed by ART after two weeks. Medium-probability patients follow the South African guidelines for test-negative tuberculosis and are reviewed within a week, to be re-categorised as low or high probability. Low-probability patients start ART as soon as possible. The primary outcome is all-cause mortality at six months. Secondary outcomes include severe morbidity, time to ART start and cost-effectiveness.

Discussion

This trial will test whether a primary care-friendly management algorithm will enable nurses to identify HIV-positive patients at the highest risk of tuberculosis, to facilitate prompt treatment and reduce early mortality. There remains an urgent need for better diagnostic tests for tuberculosis, especially for people with advanced HIV disease, which may render empirical treatment unnecessary.

Trial registration

This trial was registered with Current Controlled Trials (identifier: ISRCTN35344604) on 12 September 2012.

Tuberculosis active case finding: uptake and diagnostic yield among minibus drivers in urban South Africa

Background

Tuberculosis (TB) active case finding is a part of TB control in areas of higher TB prevalence. Congested public transportation settings may be areas of increased TB transmission. We evaluated the uptake and diagnostic yield of an active TB screening program among minibus drivers in a large public transportation facility in Johannesburg, South Africa.

Methods

Over an eight month period, we intensively recruited minibus drivers for TB screening with a goal of 80% uptake among the estimated 2000 drivers. All participants were screened for TB symptoms, offered HIV testing, and had sputum collected for smear microscopy and liquid culture.

Results

686 drivers were screened for TB, representing an uptake of only 34% of all drivers (43% of the target screening). Ten drivers (1.5%) were culture positive for TB, nine of whom were sputum smear microscopy negative. Factors associated with previously undiagnosed TB included a history of incarceration (odds ratio [OR] 5.5, 95% confidence interval: 1.1, 27.3) and HIV positivity (OR 5.3, 95% confidence interval: 1.1, 26.3).

Conclusions

We identified undiagnosed pulmonary TB cases among drivers but at a level that may be insufficient to justify systematic case finding in this population considering the poor uptake.

Tuberculosis and hepatic steatosis are prevalent liver pathology findings among HIV-infected patients in South Africa

Liver disease epidemiology in sub-Saharan Africa has shifted as a result of HIV and the increased use of antiretroviral therapy leading to a need for updated data on common causes of liver disease. We retrospectively reviewed records from all hospitalized patients who had liver biopsy at a single hospital in South Africa from 2001 to 2009 and compared diagnosis by HIV status. During the period of study 262 patients had liver biopsy, 108 (41%) were HIV-infected, 25 (10%) were HIV-sero-negative, and 129 (49%) had unknown or unrecorded HIV status. Overall 81% of biopsies provided additional diagnostic data. Malignancy was the most common finding reported on 56 (21%) biopsies followed by granuloma or TB, hepatic steatosis, and fibrosis or cirrhosis. HIV-infected patients were more likely to have granulomas and steatosis. Half of patients with granulomas were already on TB treatment, suggesting paradoxical reactions or drug induced liver injury may have been important causes of liver inflammation among these patients. We note that TB, paradoxical reactions during TB treatment, possible drug induced liver injury, and hepatic steatosis are important causes of liver pathology among HIV-infected hospitalized patients with unclear etiology of liver disease after initial assessment. Among HIV sero-negative patients, malignancy was the major cause of liver disease. Our findings re-enforce the importance of TB as a diagnosis among HIV-infected individuals.

Implementing a large-scale systematic tuberculosis screening program in correctional facilities in South Africa

Background.  Tuberculosis (TB) prevalence is high in correctional facilities in southern Africa. With support from local South African nongovernmental organizations, the South African Department of Correctional Services initiated a program of systematically screening newly admitted and current inmates for symptoms followed by GeneXpert Mycobacterium tuberculosis (MTB)/rifampicin (Rif) for microbiologic testing of symptomatic inmates. Methods.  We conducted a program evaluation during a 5-month window describing program reach, effectiveness, adoption within the facilities, cost, and opportunities for sustainability. This evaluation included 4 facilities (2 large and 2 smaller) with a total daily census of 20 700 inmates. Results.  During the 5-month evaluation window from May to September 2013, 7426 inmates were screened at the 4 facilities. This represents screening 87% of all new admits (the remaining new admits were screened by correctional staff only and are not included in these statistics) and 23% of the daily inmate census, reaching 55% of the overall screening target as calculated per annum. The reach ranged from 57% screened during these 5 months at one of the smaller facilities to 13% at the largest facility. Two hundred one cases of pulmonary TB were diagnosed, representing 2.1% of the screened population; 93% had documented initiation of TB treatment. The cost per TB case identified was $1513, excluding treatment costs (with treatment costs it was $1880). Conclusions.  We reached a large number of inmates with high-volume screening and effectively used GeneXpert MTB/Rif to diagnose pulmonary TB and rapidly initiate treatment. The cost was comparable to other screening programs.

Rationale and evidence for human immunodeficiency virus treatment as prevention at the individual and population levels

Individual health benefits of antiretroviral therapy (ART) are becoming clearer. In resource-rich countries, side effects of current ART regimens are minimal. US guidelines recommend ART regardless of CD4 count or viral load. Maintaining an undetectable viral load with ART comes close to eliminating the risk of HIV transmission, leading the US guidelines to recommend universal ART to reduce HIV transmission. Achieving population-level control through treatment as prevention (TasP) may be feasible, but requires considerable investment of resources devoted to HIV testing, linkage to care, ART accessibility, and retention in care. Ongoing studies of TasP will provide insight into achieving meaningful ART coverage.

Four models of HIV counseling and testing: utilization and test results in South Africa

BACKGROUND

HIV Counseling and Testing (HCT) is the point-of-entry for pathways of HIV care and prevention. However, HCT is not reaching many who are HIV infected and this may be related to the HCT provision model. We describe HCT utilization and HIV diagnosis using four models of HCT delivery: clinic-based, urban mobile, rural mobile, and stand-alone.

METHODS

Using cross-sectional data from routine HCT provided in South Africa, we described client characteristics and HIV test results from information collected during service delivery between January 2009 and June 2012.

RESULTS

118,358 clients received services at clinic-based units, 18,597; stand-alone, 28,937; urban mobile, 38,840; and rural mobile, 31,984. By unit, clients were similar in terms of median age (range 28-31), but differed in sex distribution, employment status, prior testing, and perceived HIV risk. Urban mobile units had the highest proportion of male clients (52%). Rural mobile units reached the highest proportion of clients with no prior HCT (61%) and reporting no perceived HIV risk (64%). Overall, 10,862 clients (9.3%) tested HIV-positive.

CONCLUSIONS

Client characteristics varied by HCT model. Importantly, rural and urban mobile units reached more men, first-time testers, and clients who considered themselves to be at low risk for HIV.

Durable HIV RNA resuppression after virologic failure while remaining on a first-line regimen: a cohort study

Adherence interventions are a recommended strategy to salvage failing antiretroviral therapy without regimen change. We assessed the durability of resuppression when using this approach. Of 300 patients who resuppressed on the same regimen (41% of all those with virologic failure), 148 (45%) remained suppressed during follow-up for a median of 2.4 years (interquartile range [IQR]: 1.1, 4.0). Resuppression can be durable following viraemia without a switch in antiretroviral therapy regimen.

Cotrimoxazole prophylaxis and tuberculosis risk among people living with HIV

Objectives

Many randomized and cohort studies have reported a survival benefit with cotrimoxazole prophylaxis without detecting a difference in tuberculosis (TB) incidence by cotrimoxazole status. However, several in vitro studies have reported that cotrimoxazole possesses anti-TB activity. We sought to compare TB incidence and TB diagnostic yield by cotrimoxazole use among participants in a well characterized cohort of HIV-infected adults living in a high TB prevalence region.

Methods

We analyzed prospective data from a long-term longitudinal cohort of adults receiving HIV care and TB investigations in Soweto, South Africa. Using longitudinal analysis, we compared total and laboratory confirmed TB incidence by cotrimoxazole status as well as all-cause mortality. In addition, we compared TB culture results by cotrimoxazole status.

Results

In a multivariable analysis, adjusted for sex, body mass index, WHO clinical stage, time-updated CD4 count, and antiretroviral therapy status, we observed an association between cotrimoxazole and an increase in TB incidence (hazard ratio 1.7, 95% CI: 1.2, 2.2). However, when restricted to laboratory-confirmed TB, there was no association between cotrimoxazole and TB incidence (hazard ratio: 0.97, 95% CI: 0.39, 2.4). In TB cases, we found no difference in the proportion of positive sputum cultures or days to culture positivity by cotrimoxazole status. Cotrimoxazole was associated with a reduction in mortality.

Conclusions

In this cohort with a mortality benefit from cotrimoxazole, we found an increased risk of all TB among individuals using cotrimoxazole, likely a result of residual confounding, but no association between use of cotrimoxazole and laboratory-confirmed TB. Cotrimoxazole did not compromise TB diagnosis.

Immunodeficiency at the start of combination antiretroviral therapy in low-, middle-, and high-income countries

OBJECTIVE

To describe the CD4 cell count at the start of combination antiretroviral therapy (cART) in low-income (LIC), lower middle-income (LMIC), upper middle-income (UMIC), and high-income (HIC) countries.

METHODS

Patients aged 16 years or older starting cART in a clinic participating in a multicohort collaboration spanning 6 continents (International epidemiological Databases to Evaluate AIDS and ART Cohort Collaboration) were eligible. Multilevel linear regression models were adjusted for age, gender, and calendar year; missing CD4 counts were imputed.

RESULTS

In total, 379,865 patients from 9 LIC, 4 LMIC, 4 UMIC, and 6 HIC were included. In LIC, the median CD4 cell count at cART initiation increased by 83% from 80 to 145 cells/μL between 2002 and 2009. Corresponding increases in LMIC, UMIC, and HIC were from 87 to 155 cells/μL (76% increase), 88 to 135 cells/μL (53%), and 209 to 274 cells/μL (31%). In 2009, compared with LIC, median counts were 13 cells/μL [95% confidence interval (CI): -56 to +30] lower in LMIC, 22 cells/μL (-62 to +18) lower in UMIC, and 112 cells/μL (+75 to +149) higher in HIC. They were 23 cells/μL (95% CI: +18 to +28 cells/μL) higher in women than men. Median counts were 88 cells/μL (95% CI: +35 to +141 cells/μL) higher in countries with an estimated national cART coverage >80%, compared with countries with <40% coverage.

CONCLUSIONS

Median CD4 cell counts at the start of cART increased 2000-2009 but remained below 200 cells/μL in LIC and MIC and below 300 cells/μL in HIC. Earlier start of cART will require substantial efforts and resources globally.

Tenofovir or zidovudine in second-line antiretroviral therapy after stavudine failure in southern Africa

BACKGROUND

There is debate over using tenofovir or zidovudine alongside lamivudine in second-line antiretroviral therapy (ART) following stavudine failure. We analysed outcomes in cohorts from South Africa, Zambia and Zimbabwe

METHODS

Patients aged ≥16 years who switched from a first-line regimen including stavudine to a ritonavir-boosted lopinavir-based second-line regimen with lamivudine or emtricitabine and zidovudine or tenofovir in seven ART programmes in southern Africa were included. We estimated the causal effect of receiving tenofovir or zidovudine on mortality and virological failure using Cox proportional hazards marginal structural models. Its parameters were estimated using inverse probability of treatment weights. Baseline characteristics were age, sex, calendar year and country. CD4(+) T-cell count, creatinine and haemoglobin levels were included as time-dependent confounders.

RESULTS

A total of 1,256 patients on second-line ART, including 958 on tenofovir, were analysed. Patients on tenofovir were more likely to have switched to second-line ART in recent years, spent more time on first-line ART (33 versus 24 months) and had lower CD4(+) T-cell counts (172 versus 341 cells/μl) at initiation of second-line ART. The adjusted hazard ratio comparing tenofovir with zidovudine was 1.00 (95% CI 0.59, 1.68) for virological failure and 1.40 (0.57, 3.41) for death.

CONCLUSIONS

We did not find any difference in treatment outcomes between patients on tenofovir or zidovudine; however, the precision of our estimates was limited. There is an urgent need for randomized trials to inform second-line ART strategies in resource-limited settings.

Resistance to tenofovir-based regimens during treatment failure of subtype C HIV-1 in South Africa

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is increasingly available for patients infected with subtype C HIV-1. This subtype is reported to develop the principal TDF resistance mutation in the HIV reverse transcriptase, K65R, with greater propensity than other subtypes. We sought to describe K65R development during TDF use in a cohort of patients infected with subtype C HIV.

METHODS

Using a prospectively followed cohort with 6 monthly HIV RNA assays, we identified virological failure (defined as an HIV RNA > 1,000 copies/ml) during treatment that included TDF. Residual serum, stored at the time of the HIV RNA assay, was used for consensus sequencing and allele-specific PCR. We assessed prevalence of resistance at failure during TDF-containing treatment and associated factors.

RESULTS

Among 1,682 patients on a TDF-containing regimen, 270 developed failure of which 40 were assessed for resistance. By sequencing, the K65R was identified in 5 (12%), major non-nucleoside reverse transcriptase inhibitor mutations in 24 (57%) and the M184V/I in 12 (28%) patients. The K65R was associated with lower HIV RNA at failure (HIV RNA 3.3 versus 4.2 log10 copies/ml) and prior stavudine exposure. An additional five patients had minority K65R populations identified by allele-specific PCR.

CONCLUSIONS

These data suggest that the K65R prevalence at virological failure is moderately higher in our subtype C population than some non-subtype C HIV cohorts. However, we did not find that the K65R was highly selected in HIV-1 subtype-C-infected patients with up to 6 months of failure of a TDF-containing regimen.

Prevalence and associations with hepatitis B and hepatitis C infection among HIV-infected adults in South Africa

We assessed prevalence and factors associated with hepatitis B in a cross section of HIV-infected primary care and antinatal clinic patients in South Africa and evaluated a rapid hepatitis B surface antigen (HBsAg) assay. We enrolled 998 patients; 88% were women, median age was 29 years and median CD4 count was 354 cells/mm(3). HBsAg enzyme-linked immunosorbent assay (ELISA), anti-hepatitis B core (HBc) antibodies and hepatitis C virus antibody were positive among 4.2%, 37% and 0.1% of subjects, respectively. Univariate and multivariate associations were assessed using logistic regression. Anti-HBc antibodies were associated with alcohol use, traditional medicines and higher CD4 counts; HBsAg positivity was associated with lower CD4. Compared with the HBsAg ELISA, a rapid HBsAg test had a sensitivity of 75.0% and specificity of 99.6%. In conclusion, we identified a moderate prevalence of both HBsAg and anti-HBc. Importantly, we found that subjects with HBsAg positivity had lower CD4 counts.

Comparison of tenofovir, zidovudine, or stavudine as part of first-line antiretroviral therapy in a resource-limited-setting: a cohort study

BACKGROUND

Tenofovir (TDF) is part of the WHO recommended first-line antiretroviral therapy (ART); however, there are limited data comparing TDF to other nucleoside reverse transcriptase inhibitors in resource-limited-settings. Using a routine workplace and community-based ART cohort in South Africa, we assessed single drug substitution, HIV RNA suppression, CD4 count increase, loss-from-care, and mortality between TDF, stavudine (d4T) 30 mg dose, and zidovudine (AZT).

METHODS

In a prospective cohort study we included ART naïve patients aged ≥17 years-old who initiated ART containing TDF, d4T, or AZT between 2007 and 2009. For analysis of single drug substitutions we used a competing-risks time-to-event analysis; for loss-from-care, mixed-effect Poisson modeling; for HIV RNA suppression, competing-risks logistic regression; for CD4 count slope, mixed-effects linear regression; and for mortality, proportional hazards modeling.

RESULTS

Of 6,196 patients, the initial drug was TDF for 665 (11%), d4T for 4,179 (68%), and AZT for 1,352 (22%). During the first 6 months of ART, the adjusted hazard ratio for a single drug substitution was 2.3 for d4T (95% confidence interval [CI]: 0.27, 19) and 5.2 for AZT (95% CI: 1.1, 23), compared to TDF; whereas, after 6 months, it was 10 (95% CI: 5.8, 18) and 4.4 (95% CI: 2.5, 7.8) for d4T and AZT, respectively. Virologic suppression was similar by agent; however, CD4 count rise was lowest for AZT. The adjusted hazard ratio for loss-from-care, when compared to TDF, was 1.5 (95% CI: 1.1, 1.9) for d4T and 1.2 (95% CI: 1.1, 1.4) for AZT. The adjusted hazard ratio for mortality, when compared to TDF, was 2.7 (95% CI: 2.0, 3.5) and 1.4 (95% CI: 1.3, 1.5) and for d4T and AZT, respectively.

DISCUSSION

In routine care, TDF appeared to perform better than either d4T or AZT, most notably with less drug substitution and mortality than for either other agent.

High prevalence of pulmonary tuberculosis but low sensitivity of symptom screening among HIV-infected pregnant women in South Africa

Symptom screening is a recommended component of intensified case-finding (ICF) for pulmonary tuberculosis (TB) among HIV-infected individuals. Symptomatic individuals are further investigated to either exclude or diagnose pulmonary TB, thus reducing the number of individuals requiring costly laboratory investigation. Those with laboratory evaluations negative for pulmonary TB or who lack symptoms may be eligible for antiretroviral therapy (ART) and/or TB isoniazid preventive therapy (IPT). A four-part symptom screen has been recommended by the World Health Organization (WHO) for identifying TB suspects and those unlikely to have TB. A meta-analysis of studies among HIV-infected individuals calculated a sensitivity of 90.1% for the four-part symptoms screen - of any of cough, fever, night sweats, or weight loss - among patients in clinical care, making it an effective tool for identifying most patients with TB. An important population for intensified case-finding not included in that meta-analysis was HIV-infected pregnant women. We undertook a cross-sectional survey among HIV-infected pregnant women receiving prenatal care at community clinics in South Africa. We obtained a four-symptom review and sputum smear microscopy and mycobacterial culture on all participants. Among 1415 women, 226 (16%) had a positive symptom screen, and 35 (2.5%) were newly diagnosed with culture-positive TB. Twelve were on TB treatment at the time of screening, yielding 47 (3.3%) women with prevalent TB. Symptom screening among women without known TB had a sensitivity of 28% and specificity of 84%. The poor performance of symptom screening to identify women with TB suggests that other approaches may be needed for intensified case-finding to be effective for this population.

Life expectancies of South African adults starting antiretroviral treatment: collaborative analysis of cohort studies

BACKGROUND

Few estimates exist of the life expectancy of HIV-positive adults receiving antiretroviral treatment (ART) in low- and middle-income countries. We aimed to estimate the life expectancy of patients starting ART in South Africa and compare it with that of HIV-negative adults.

METHODS AND FINDINGS

Data were collected from six South African ART cohorts. Analysis was restricted to 37,740 HIV-positive adults starting ART for the first time. Estimates of mortality were obtained by linking patient records to the national population register. Relative survival models were used to estimate the excess mortality attributable to HIV by age, for different baseline CD4 categories and different durations. Non-HIV mortality was estimated using a South African demographic model. The average life expectancy of men starting ART varied between 27.6 y (95% CI: 25.2-30.2) at age 20 y and 10.1 y (95% CI: 9.3-10.8) at age 60 y, while estimates for women at the same ages were substantially higher, at 36.8 y (95% CI: 34.0-39.7) and 14.4 y (95% CI: 13.3-15.3), respectively. The life expectancy of a 20-y-old woman was 43.1 y (95% CI: 40.1-46.0) if her baseline CD4 count was ≥ 200 cells/µl, compared to 29.5 y (95% CI: 26.2-33.0) if her baseline CD4 count was <50 cells/µl. Life expectancies of patients with baseline CD4 counts ≥ 200 cells/µl were between 70% and 86% of those in HIV-negative adults of the same age and sex, and life expectancies were increased by 15%-20% in patients who had survived 2 y after starting ART. However, the analysis was limited by a lack of mortality data at longer durations.

CONCLUSIONS

South African HIV-positive adults can have a near-normal life expectancy, provided that they start ART before their CD4 count drops below 200 cells/µl. These findings demonstrate that the near-normal life expectancies of HIV-positive individuals receiving ART in high-income countries can apply to low- and middle-income countries as well. Please see later in the article for the Editors' Summary.

A novel HIV treatment model using private practitioners in South Africa

OBJECTIVES

The extent of the HIV epidemic in South Africa may render the public sector capacity inadequate to manage all patients requiring antiretroviral treatment (ART). Private practitioners are an underutilised resource.

METHODS

The authors developed a model of care using 72 private practitioners in five provinces in urban and rural areas of South Africa with centralised clinical support, training, pharmacy control and data management. The authors describe the programme, its quality control measures and patient outcomes using a cohort analysis.

RESULTS

Between January 2005 and December 2008, 9102 individuals were started on ART, 62% female, median age 34 years, median viral load 50,655 copies/ml and median baseline CD4 count 123 cells/μl. Retention (alive and in care) after 12 months was 63% in the 2005 cohort (646 of 1026) and remained similar in the other calendar years, 58%, 68% and 64% in 2006, 2007 and 2008, respectively. After 36 months, retention was 50% and 41% for those enrolled in 2005 and 2006, respectively. The percentage virally suppressed remained similar at 6 months, 82% vs 84%, 84% and 85% from 2005, 2006, 2007 to 2008, respectively, p=0.66; but improved slightly at 12 months, 78% vs 83%, 83% and 84% from 2005 to 2008, p=0.05. At 36 months, it was 84% and 82% for the 2005 and 2006 cohorts, respectively.

CONCLUSIONS

The results show that a well-managed private practitioner model can achieve comparable results to public services, although long-term retention needs further evaluation. This model of ART delivery can be used to expand access to ART in areas where the public sector is unable to meet the demand.

Gender differences in survival among adult patients starting antiretroviral therapy in South Africa: a multicentre cohort study

BACKGROUND

Increased mortality among men on antiretroviral therapy (ART) has been documented but remains poorly understood. We examined the magnitude of and risk factors for gender differences in mortality on ART.

METHODS AND FINDINGS

Analyses included 46,201 ART-naïve adults starting ART between January 2002 and December 2009 in eight ART programmes across South Africa (SA). Patients were followed from initiation of ART to outcome or analysis closure. The primary outcome was mortality; secondary outcomes were loss to follow-up (LTF), virologic suppression, and CD4+ cell count responses. Survival analyses were used to examine the hazard of death on ART by gender. Sensitivity analyses were limited to patients who were virologically suppressed and patients whose CD4+ cell count reached >200 cells/µl. We compared gender differences in mortality among HIV+ patients on ART with mortality in an age-standardised HIV-negative population. Among 46,201 adults (65% female, median age 35 years), during 77,578 person-years of follow-up, men had lower median CD4+ cell counts than women (85 versus 110 cells/µl, p<0.001), were more likely to be classified WHO stage III/IV (86 versus 77%, p<0.001), and had higher mortality in crude (8.5 versus 5.7 deaths/100 person-years, p<0.001) and adjusted analyses (adjusted hazard ratio [AHR] 1.31, 95% CI 1.22-1.41). After 36 months on ART, men were more likely than women to be truly LTF (AHR 1.20, 95% CI 1.12-1.28) but not to die after LTF (AHR 1.04, 95% CI 0.86-1.25). Findings were consistent across all eight programmes. Virologic suppression was similar by gender; women had slightly better immunologic responses than men. Notably, the observed gender differences in mortality on ART were smaller than gender differences in age-standardised death rates in the HIV-negative South African population. Over time, non-HIV mortality appeared to account for an increasing proportion of observed mortality. The analysis was limited by missing data on baseline HIV disease characteristics, and we did not observe directly mortality in HIV-negative populations where the participating cohorts were located.

CONCLUSIONS

HIV-infected men have higher mortality on ART than women in South African programmes, but these differences are only partly explained by more advanced HIV disease at the time of ART initiation, differential LTF and subsequent mortality, and differences in responses to treatment. The observed differences in mortality on ART may be best explained by background differences in mortality between men and women in the South African population unrelated to the HIV/AIDS epidemic. Please see later in the article for the Editors' Summary.

Viremia, resuppression, and time to resistance in human immunodeficiency virus (HIV) subtype C during first-line antiretroviral therapy in South Africa

BACKGROUND

Episodes of viremia are common in African antiretroviral therapy (ART) programs. We sought to describe viremia, resuppression, and accumulation of resistance during first-line combination ART (cART) in South Africa.

METHODS

Retrospective analysis of a cohort receiving zidovudine, lamivudine, and either efavirenz or nevirapine with human immunodeficiency virus (HIV) RNA monitoring every 6 months. We assessed viremia (HIV RNA >1000 copies/mL after initial HIV RNA response) and resuppression (HIV RNA <400 copies/mL after viremia). Genotypic resistance testing was performed using stored plasma on a subset of patients at first detection of viremia and subsequently among patients with persistent viremia.

RESULTS

Between 2002 and 2006, 3727 patients initiated cART (median CD4, 147 cells/mm(3)). Of 1007 patients who developed viremia, 815 had subsequent HIV RNA assays, and 331 (41%) of these resuppressed without regimen switch. At identification of viremia, 45 (66%) of 68 patients had HIV-1 drug resistance, 42 (62%) had nonnucleoside reverse-transcriptase inhibitor (NNRTI)-resistance, 25 (37%) had M184V/I, and 4 (6%) had multi-nucleoside analogue drug mutations. By 12 months of persistent viremia among a subset of 14 patients with resistance testing to 12 months, 11 (78%) had nonnucleoside reverse-transcriptase inhibitor (NNRTI)-resistance, 8 (57%) had M184V/I, and 2 (14%) had multi-nucleoside analogue drug mutations. Resistance was associated with a reduced probability of resuppression; however, 50% of patients with NNRTI resistance resuppressed while receiving an NNRTI.

CONCLUSIONS

The majority of patients had NNRTI resistance mutations at detection of viremia. However, 41% resuppressed without regimen switch. Our findings support maximizing first-line use while minimizing risk of significant cross-resistance by implementing intensive adherence support and repeat HIV RNA testing 3-6 months after detecting viremia, with regimen switch only if viremia persists.

Hepatitis B and long-term HIV outcomes in coinfected HAART recipients

BACKGROUND

Chronic hepatitis B (CH-B) is common among HIV-infected individuals and increases liver-related mortality in the absence of HAART. The impact of CH-B on long-term HAART outcomes has not been fully characterized.

METHODS

To address this question, HAART initiators enrolled in the Multicenter AIDS Cohort Study were retrospectively analyzed. Patients were classified by hepatitis B category based on serology at the time of HAART initiation. The association of CH-B with mortality, AIDS-defining illnesses, CD4 cell rise, and HIV suppression was assessed using regression analysis.

RESULTS

Of 816 men followed for a median of 7 years on HAART, 350 were never hepatitis B virus (HBV) infected, 357 had past infection, 45 had CH-B, and 64 were only core-antibody positive. Despite HAART, AIDS-related mortality was the most common cause of death [8.3/1000 person-years (PYs)]. It was highest in those with CH-B (17/1000 PYs, 95% confidence interval 7.3, 42) and lowest among never HBV infected (2.9/1000 PYs, 95% confidence interval 1.4, 6.4). In a multivariable model, patients with CH-B had a 2.7-fold higher incidence of AIDS-related mortality compared with those never infected (P = 0.08). Non-AIDS-related mortality was also highest among those with CH-B (22/1000 PYs), primarily due to liver disease (compared to never infected, adjusted hazard ratio 4.1, P = 0.04). There was no significant difference in AIDS-defining events, HIV RNA suppression, and CD4 cell increase.

CONCLUSION

In HIV-infected patients receiving long-term HAART, HBV status did not influence HIV suppression or CD4 cell increase. However, mortality was highest among those with CH-B and was mostly due to liver disease despite HBV-active HAART.

Hepatitis B virus infection and response to antiretroviral therapy (ART) in a South African ART program

BACKGROUND

Coinfection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV) is common in Africa; however, the impact of HBV infection on the outcomes of antiretroviral therapy programs is unclear. We evaluated the impact of chronic hepatitis B on HIV virologic response, changes in CD4 cell count, hepatotoxicity, and mortality among Africans receiving highly active antiretroviral therapy (HAART).

METHODS

We conducted a retrospective cohort study involving a workplace HAART program in South Africa. Participants received HAART according to a protocol and were followed up for up to 72 weeks. On the basis of pre-HAART serum assays, patients were classified as being hepatitis B surface antigen (HBsAg) negative, HBsAg positive with a low HBV DNA level (</= 1 x 10(4) copies/mL), and HBsAg positive with a high HBV DNA level (> 1 x 10(4) copies/mL). The relationships between HBV status and HIV RNA suppression, change in CD4 cell count, mortality, and hepatotoxicity were assessed with use of regression techniques.

RESULTS

Five hundred thirty-seven individuals fulfilled the inclusion criteria; 431 (80.3%) of these patients were HBsAg negative, 60 (11.2%) were HBsAg positive with a low HBV DNA level, and 46 (8.6%) were HBsAg positive with a high HBV DNA level. All groups had similar rates of HIV RNA suppression (P = .61), CD4 cell count increases (P =.75), and mortality (17 total deaths; P=.11) for up to 72 weeks after the initiation of HAART. Baseline transaminase levels were highest in the group with high HBV DNA levels (P=.004). Hepatotoxicity was similar between the HBsAg-negative group and the group with low HBV DNA levels but was higher in the group with high HBV DNA levels (incidence rate ratio, 4.4).

CONCLUSIONS

We revealed that HBV status does not affect HIV RNA suppression, CD4 cell count response, or mortality during the first 72 weeks of HAART in an African setting. The risk of HBV-associated hepatotoxicity, however, is associated with the baseline HBV DNA level.

Thyroid function abnormalities in HIV-infected patients

Abnormal thyroid function test results are common among human immunodeficiency virus (HIV)-infected patients. Although the prevalence of overt thyroid disease does not appear to be significantly increased in HIV-infected patients, compared with the general population, specific patterns of abnormal thyroid function test findings are more frequently identified among HIV-infected patients. Among patients with advanced acquired immunodeficiency syndrome, nonthyroidal illness (i.e., euthyroid sick syndrome) is common. During antiretroviral therapy, the prevalence of 2 generally asymptomatic conditions (subclinical hypothyroidism, which is characterized by isolated elevated thyroid-stimulating hormone levels, and isolated low free thyroxine levels) is increased. In addition, Graves disease, which is marked by low thyroid-stimulating hormone and elevated thyroxine levels, may occur during immune reconstitution. Testing for thyroid disease among symptomatic patients should begin with measurement of the thyroid-stimulating hormone level. However, there is insufficient evidence to recommend routine thyroid screening of asymptomatic HIV-infected individuals. This review summarizes the current evidence regarding the optimal laboratory evaluation of thyroid function; highlights the causes, presentation, and treatment of thyroid dysfunction in HIV-infected patients; and discusses the controversies regarding screening.

Hepatotoxicity in an African antiretroviral therapy cohort: the effect of tuberculosis and hepatitis B

OBJECTIVE

Hepatotoxicity is a significant complication of antiretroviral therapy (ART). We assessed the incidence of and risk factors for hepatotoxicity among HIV-infected individuals on ART in South Africa.

DESIGN

We conducted a retrospective cohort study in a workplace HIV care program in South Africa which uses a first-line regimen of efavirenz, zidovudine, and lamivudine and provides routine clinical and laboratory monitoring.

METHODS

We included subjects with baseline and follow-up alanine transaminase and aspartate aminotransferase tests. Severe hepatotoxicity cases were identified during the first 12 months of ART. Potential risk factors, including concomitant medication use, tuberculosis, and hepatitis B and C, were determined from clinical records, database queries, and serological testing. Associations with hepatotoxicity were investigated using Cox proportional hazards modeling.

RESULTS

Of the 868 subjects (94% male, median age 41 years), the median nadir CD4 cell count was 136/microl, 25% received concomitant tuberculosis treatment during ART, and 17% of a randomly selected subset were positive for hepatitis B surface antigen (HBsAg). We identified 7.7 episodes of severe hepatotoxicity per 100 person-years. Tuberculosis treatment increased risk 8.5 fold, positive HBsAg 3.0 fold, and nadir CD4 cells count < 100/microl 1.9 fold. Importantly, the fraction of patients with severe hepatotoxicity on ART (4.6%) was similar to the fraction with liver enzyme elevations > 5 times the upper limit of normal before starting ART (4%).

CONCLUSIONS

In this African ART cohort, we found a low incidence of and minimal morbidity due to hepatotoxicity. HBsAg and concomitant tuberculosis therapy significantly increased the risk of hepatotoxicity.

Clinical implications of HIV and hepatitis B co-infection in Asia and Africa

Hepatitis B virus (HBV) is the leading cause of chronic liver disease and liver-related death worldwide, with the majority of these cases occurring in areas of Africa and Asia where HBV prevalence is high. Many of the countries that are affected by hepatitis B are also affected by a high HIV burden, leading to frequent HIV/HBV co-infection. The consequences of co-infection, including increased liver-related morbidity and mortality, increased hepatitis B viral replication, immune reconstitution to HBV in the setting of antiretroviral therapy, and hepatotoxicity from antiretroviral drugs, are especially important in regions with expanding antiretroviral programmes. Little data, however, are available on HIV/HBV co-infection from regions with high chronic hepatitis B prevalence. This Review discusses the epidemiology, natural history, pathogenesis, and management of HIV/HBV co-infection from these areas. Topics for future research relevant to HIV/HBV co-infection in Africa and Asia are also highlighted.

Neurocysticercosis in Oregon, 1995-2000

The unexpected death of a teenager from neurocysticercosis prompted an investigation of this disease in Oregon. We found 89 hospitalizations, 43 newly diagnosed cases, and 6 deaths from 1995 to 2000. At least five cases occurred in persons who had not traveled or lived outside the United States. Enhanced surveillance for neurocysticercosis is warranted.

Emphysematous cystitis: a review of the spectrum of disease

Emphysematous cystitis is an uncommon condition in which pockets of gas are formed in and around the bladder wall by gas-forming organisms. Persons with diabetes, neurogenic bladder and chronic urinary infection are predisposed to the disease. Severity of illness ranges from an asymptomatic condition to life-threatening cystitis. We present 2 cases of emphysematous cystitis. One case was an incidental finding on evaluation of abdominal discomfort with resolution upon removal of predisposing factors. The other patient presented with an acute abdomen that progressed to severe necrotizing cystitis ultimately requiring cystectomy. The initial involvement of the urologist as a consultant is emphasized. A complete review of the literature describes the incidence, various presentations, associated diseases and organisms, pathogenesis, and available methods for diagnosis and treatment reported for this disease. Successful management depends on early diagnosis with correction of underlying causes, administration of appropriate antibiotics, establishment of adequate bladder drainage and surgical excision of involved tissue when required. Early detection and prompt treatment are encouraged.

Altered 5'-nucleotidase specific activity and distribution between two plasma membrane domains of ascites tumor cells with modified lipid composition

1. The cholesterol and phospholipid content of the surface membranes of ascites tumor cells cultivated in lipid-depleted medium was reduced to about 60(70)% of the control, but the relative composition of the individual phospholipids was not altered. 2. Differences in lipid composition were also observed between the two plasma membrane domains isolated from the cells cultured in normal and lipid-depleted medium respectively. 3. The fatty acid spectrum of the lipid-depleted membranes showed a greater fraction of saturated vs unsaturated acids. 4. The membrane lipid fluidity measured by fluorescence polarization was decreased in the modified surface membranes. 5. The 5'-nucleotidase specific activity was drastically reduced (46-66%) in the lipid-deleted membranes, and in addition its distribution between the two vesicle fractions was altered.

Influence of triethyl lead on the activity of enzymes of the ascites tumor cell plasma membrane and its microviscosity

The influence of triethyl lead (TriEL) on the activity of plasma membrane-bound enzymes of Ehrlich ascites tumor cells and on membrane fluidity has been investigated. TriEL completely inhibits the (Na+-K+)-ATPase in its membrane-bound and even more pronounced in its solubilized form between 5 and about 20 microM. It also alters the microviscosity of the isolated plasma membrane up to a temperature of about 30 degrees C, but it does not have any influence on the fluidity of the membrane-derived liposomes. From these data it is concluded that the inhibitor may interact directly with the catalytic subunit of the (Na+ + K+)-ATPase, and may not exert its influence by interfering with the membrane lipids.

Cholesterol-induced growth stimulation, cell aggregation, and membrane properties of ascites tumor cells in culture

Ascites tumor cells can be cultivated at a reduced serum concentration if cholesterol (2.50 mg per 100 ml of medium) is added to the culture medium. At serum concentrations of 3%, optimal growth properties are obtained; below 3%, cell cultures usually perish after a few days. Cells grown in the presence of added cholesterol have an elevated content of this molecule per cell as well as in the plasma membrane, and they also show a cholesterol concentration-dependent rate of proliferation. Precursors of the cholesterol-biosynthetic pathway like mevalonic acid, added in mM amounts, or squalene and lanosterol cannot be substituted for cholesterol itself. This is due to the observation that the biosynthetic pathway is blocked at the stage of lanosterol conversion to cholesterol. Cholesterol de novo synthesis from acetate is regulated by the cholesterol content of the cells, which also affects the production of ubiquinone and dolichol. Growth factors such as insulin, prostaglandin F2 alpha, and transferrin added to the medium do not mimic the cholesterol-induced effect. Distribution of DNA during cell cycle and the cell density-dependent reduction in macromolecule synthesis is very similar to the control cells. In contrast, cells without added cholesterol show reduced growth properties accompanied by the accumulation of cells in the mitotic and G2 phase. The cholesterol/phospholipid ratio of the plasma membranes of cholesterol-rich cells is about 15% lower than of the control cells and 40% higher compared to the cholesterol-poor cells, which, however, does not significantly alter the membrane fluidity between the cholesterol-rich and -poor cells as revealed by fluorescence polarization measurements. The most dramatic behavior of the cholesterol-rich cells is their tendency to form aggregates, which is demonstrated either by concanavalin A-induced agglutination or by cell density-dependent aggregation shown by interference microscopy in vivo.

Structural and functional alterations of lipid-depleted ascites tumor cells in culture

Ascites tumor cells growth-arrested in lipid-depleted medium were modified with respect to their lipid composition, i.e. mainly cholesterol and the phospholipid fraction. These so-called lipid-depleted cells were generally smaller, had a surface area reduced by 55% compared to the control cells and had an altered cell surface architecture with large parts being smooth, interrupted by isolated bundles of microvilli and blebs as revealed by scanning electron microscopy. This deorganization process of the cells. Lectin-induced agglutination and receptor binding capacity was reduced, and also the receptor distribution was changed resulting in a cap-like formation on the surface as shown with FITC-labelled concanavalin A. The reduction in lipid content yielding a lower C/P ratio profoundly decreased the plasma membrane fluidity which was determined by fluorescence polarization measurements. Studies on fatty acid and cholesterol de novo synthesis revealed only small increases under lipid-free conditions not sufficient to meet the requirements of the lipid-depleted cells for these substances. It is therefore concluded that ascites tumor cells need exogenous preformed lipids for adequate functioning of the cell.