Background

Emergence of complex HIV-1 drug resistance mutations has been linked to the duration of time on a failing antiretroviral (ARV) drug regimen. This study reports on resistance profiles in a closely monitored subtype C infected cohort.

Methods

A total of 812 participants were enrolled into the CIPRA-SA ‘safeguard the household’ study, viral loads (VLs) were performed 12 weekly for 96 weeks. Virological failure was defined as either <1.5 log drop in VL at week 12 or 2 consecutive VL measurements >1000 RNA copies/ml after week 24. Regimens prescribed were in-line with the South African roll-out program (d4T, 3TC, EFV or NVP). Viral RNA was extracted from patients with virological failure, and pol RT-PCR and sequence analysis were performed to determine drug resistance mutations.

Results

Eighty three participants experienced virological failure on the first-line regimen during the study period, of which 61 (73%) had HIV-1 drug resistance mutations. The M184V mutation was the most frequent (n=46; 65%), followed by K103N (46%) and Y181C (21%). TAMS were infrequent (1%) and Q151M was not observed.

Conclusion

Drug resistance profiles were less complex than has been previously reported in South Africa using the same ARV drug regimens. This data suggests that frequent viral load monitoring limits the level and complexity of resistance observed in HIV-1 subtype C, preserving susceptibility to second-line options.

Objective

In April 2010 the South African government added Tenofovir disoproxil fumarate to its first-line antiretroviral therapy (ART) for HIV patients. We analyzed the relationship between renal dysfunction at tenofovir initiation, nephrotoxicity and mortality.

Design

Retrospective cohort analysis of HIV-infected adults who received tenofovir and had a creatinine clearance done at initiation at the Themba Lethu Clinic, Johannesburg, South Africa between April 2004-September 2009.

Methods

We estimated the relationship between renal dysfunction, nephrotoxicity [any decline in kidney function from baseline (acute or chronic) that is secondary to a toxin (including drugs)] and mortality for patients initiated on tenofovir-containing regimens using marginal structural models and inverse probability of treatment weights to correct estimates for lost to follow-up and confounding.

Results

Of 890 patients initiated on tenofovir, 573 (64.4%) had normal renal function (>90ml/min), 271 (30.4%) had mild renal dysfunction (60-89ml/min) and 46 (5.2%) had moderate renal dysfunction (30-59ml/min). 2.4% experienced nephrotoxicity, 7.8% died and 9.7% were lost during 48-months of follow-up. Patients with mild (HR 4.8; 95%CI: 1.5-15.2) or moderate (HR 15.0; 95%CI: 3.4-66.5) renal dysfunction were at greatest risk of nephrotoxicty, while those with mild (HR 1.2; 95%CI: 0.7-2.3) or moderate (HR 3.2; 95%CI: 1.3-7.8) renal dysfunction vs. normal renal function were at highest risk of death by 48-months.

Conclusion

Much of the incident renal dysfunction in tenofovir patients is likely related to pre-existing renal pathology, which may be exacerbated by tenofovir. With expanded use of tenofovir, screening for renal dysfunction prior to initiation and dose adjustment is necessary to help improve ART outcomes.

Objective

We investigated the effect of oropharyngeal candidiasis (OC) and body mass index (BMI) prior to ART initiation on treatment outcomes of HIV-positive patients.

Methods

Treatment outcomes included failure to increase CD4 count by ≥50 or ≥100cells/mm3 or failure to suppress viral load (<400copies/ml) at 6- or 12-months in addition to loss to follow-up (LTFU) and mortality by 12-months. Risk and hazard ratios were estimated using log-binomial regression and Cox proportional hazards models, respectively.

Results

Baseline CD4 <100cells/mm3, low BMI (<18.5 kg/m2), low hemoglobin and elevated aspartate transaminase were associated with OC at ART initiation. Patients with low BMI with/without OC were at risk of mortality (Hazard Ratio (HR)2.42 95%CI 1.88–3.12; HR1.87 95% CI 1.54-2.28) and LTFU (HR1.36 95%CI 1.02–1.82; HR1.55 95% CI 1.30-1.85).

Conclusion

Low BMI (with/without OC) at ART initiation was associated with poor treatment outcomes. Conversely, normal BMI with OC was associated with adequate CD4 response and reduced LTFU compared to without OC.

Objective

To assess the outcomes of linkage to TB and HIV care and identify risk factors for poor referral outcomes.

Design

Cohort study of TB patients diagnosed at an urban hospital.

Methods

Linkage to care was determined by review of clinic files, national death register, and telephone contact, and classified as linked to care, delayed linkage to care (>7 days for TB treatment, >30 days for HIV care), or failed linkage to care. We performed log-binomial regression to identify patient and referral characteristics associated with poor referral outcomes.

Results

Among 593 TB patients, 23% failed linkage to TB treatment and 30.3% of the 77.0% who linked to care arrived late. Among 486 (86.9%) HIV-infected TB patients, 38.3% failed linkage to HIV care, and 32% of the 61.7% who linked to care presented late. One in six HIV-infected patients failed linkage to both TB and HIV care. Only 20.2% of HIV-infected patients were referred to a single clinic for integrated care. A referral letter was present in 90.3%, but only 23.7% included HIV status and 18.8% CD4 cell count. Lack of education (RR 1.85) and low CD4 count (CD4≤50 vs. >250cells/mm3; RR 1.66) were associated with failed linkage to TB care. Risk factors for failed linkage to HIV care were antiretroviral-naïve status (RR 1.29), and absence of referral letter with HIV or CD4 cell count (RR1.23).

Conclusions

Linkage to TB/HIV care should be strengthened by communication of HIV and CD4 results, ART initiation during hospitalization and TB/HIV integration at primary care.

Background

As the current HIV-positive population ages, the absolute number of patients >50 years on treatment is increasing.

Methods

We analyse differences in treatment outcomes by age category (18-29, 30-39, 40-49, 50-59 and ≥60) among 9139 HIV-positive adults initiating ART in South Africa.

Results

The adjusted hazard ratios for all-cause mortality increased with increasing age, with the strongest association in the first 12-months of follow-up amongst 50-59 (HR 1.67; 95% CI: 1.24-2.23) vs. those <30. However, patients 50-59 years were less likely to be lost during 24-months on ART (HR 0.75; 95% CI: 0.59-0.94) vs. <30. By 6- and 12-months on treatment, older patients were less likely to increase their CD4 count by ≥50 cells/mm3.

Conclusion

While older patients are at higher risk of mortality and have poorer immunological responses than their younger counterparts, they are more likely to adhere to care and treatment in the first 24-months on ART.

Since its inception in 2003, the US President’s Emergency Plan for AIDS Relief (PEPFAR) has been an important driving force behind the global scale-up of HIV care and treatment services, particularly in expansion of access to antiretroviral therapy. Despite initial concerns about cost and feasibility, PEPFAR overcame challenges by leveraging and coordinating with other funders, by working in partnership with the most affected countries, by supporting local ownership, by using a public health approach, by supporting task-shifting strategies, and by paying attention to health systems strengthening. As of September 2011, PEPFAR directly supported initiation of antiretroviral therapy for 3.9 million people and provided care and support for nearly 13 million people. Benefits in terms of prevention of morbidity and mortality have been reaped by those receiving the services, with evidence of societal benefits beyond the anticipated clinical benefits. However, much remains to be accomplished to achieve universal access, to enhance the quality of programs, to ensure retention of patients in care, and to continue to strengthen health systems.

Objective

We estimated the incremental cost and impact on diagnosis and treatment uptake of national rollout of Xpert MTB/RIF technology (Xpert) for the diagnosis of pulmonary TB above the cost of current guidelines for the years 2011 to 2016 in South Africa.

Methods

We parameterised a population-level decision model with data from national-level TB databases (n = 199,511) and implementation studies. The model follows cohorts of TB suspects from diagnosis to treatment under current diagnostic guidelines or an algorithm that includes Xpert. Assumptions include the number of TB suspects, symptom prevalence of 5.5%, annual suspect growth rate of 10%, and 2010 public-sector salaries and drug and service delivery costs. Xpert test costs are based on data from an in-country pilot evaluation and assumptions about when global volumes allowing cartridge discounts will be reached.

Results

At full scale, Xpert will increase the number of TB cases diagnosed per year by 30%–37% and the number of MDR-TB cases diagnosed by 69%–71%. It will diagnose 81% of patients after the first visit, compared to 46% currently. The cost of TB diagnosis per suspect will increase by 55% to USD 60–61 and the cost of diagnosis and treatment per TB case treated by 8% to USD 797–873. The incremental capital cost of the Xpert scale-up will be USD 22 million and the incremental recurrent cost USD 287–316 million over six years.

Conclusion

Xpert will increase both the number of TB cases diagnosed and treated and the cost of TB diagnosis. These results do not include savings due to reduced transmission of TB as a result of earlier diagnosis and treatment initiation.

Luis Montaner and colleagues retrospectively apply a potential capacity-saving CD4 count prediction tool to a cohort of HIV patients on antiretroviral therapy.

Background

Global programs of anti-HIV treatment depend on sustained laboratory capacity to assess treatment initiation thresholds and treatment response over time. Currently, there is no valid alternative to CD4 count testing for monitoring immunologic responses to treatment, but laboratory cost and capacity limit access to CD4 testing in resource-constrained settings. Thus, methods to prioritize patients for CD4 count testing could improve treatment monitoring by optimizing resource allocation.

Methods and Findings

Using a prospective cohort of HIV-infected patients (n = 1,956) monitored upon antiretroviral therapy initiation in seven clinical sites with distinct geographical and socio-economic settings, we retrospectively apply a novel prediction-based classification (PBC) modeling method. The model uses repeatedly measured biomarkers (white blood cell count and lymphocyte percent) to predict CD4+ T cell outcome through first-stage modeling and subsequent classification based on clinically relevant thresholds (CD4+ T cell count of 200 or 350 cells/µl). The algorithm correctly classified 90% (cross-validation estimate = 91.5%, standard deviation [SD] = 4.5%) of CD4 count measurements <200 cells/µl in the first year of follow-up; if laboratory testing is applied only to patients predicted to be below the 200-cells/µl threshold, we estimate a potential savings of 54.3% (SD = 4.2%) in CD4 testing capacity. A capacity savings of 34% (SD = 3.9%) is predicted using a CD4 threshold of 350 cells/µl. Similar results were obtained over the 3 y of follow-up available (n = 619). Limitations include a need for future economic healthcare outcome analysis, a need for assessment of extensibility beyond the 3-y observation time, and the need to assign a false positive threshold.

Conclusions

Our results support the use of PBC modeling as a triage point at the laboratory, lessening the need for laboratory-based CD4+ T cell count testing; implementation of this tool could help optimize the use of laboratory resources, directing CD4 testing towards higher-risk patients. However, further prospective studies and economic analyses are needed to demonstrate that the PBC model can be effectively applied in clinical settings.

Please see later in the article for the Editors' Summary

Editors' Summary

Background

AIDS has killed nearly 30 million people since 1981, and about 34 million people (most of them living in low- and middle-income countries) are now infected with HIV, the virus that causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte and one of the body's white blood cell types), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected people died within ten years of infection. Then, in 1996, antiretroviral therapy (ART) became available, and for people living in affluent countries, HIV/AIDS became a chronic condition. However, ART was expensive, and for people living in developing countries, HIV/AIDS remained a fatal illness. In 2003, HIV was declared a global health emergency, and in 2006, the international community set itself the target of achieving universal access to ART by 2010. By the end of 2010, only 6.6 million of the estimated 15 million people in need of ART in developing countries were receiving ART.

Why Was This Study Done?

One factor that has impeded progress towards universal ART coverage has been the limited availability of trained personnel and laboratory facilities in many developing countries. These resources are needed to determine when individuals should start ART—the World Health Organization currently recommends that people start ART when their CD4 count drops below 350 cells/µl—and to monitor treatment responses over time so that viral resistance to ART is quickly detected. Although a total lymphocyte count can be used as a surrogate measure to decide when to start treatment, repeated CD4 cell counts are the only way to monitor immunologic responses to treatment, a level of monitoring that is rarely sustainable in resource-constrained settings. A method that optimizes resource allocation by prioritizing who gets tested might be one way to improve treatment monitoring. In this study, the researchers applied a new tool for prioritizing laboratory-based CD4 cell count testing in resource-constrained settings to patient data that had been previously collected.

What Did the Researchers Do and Find?

The researchers fitted a mixed-effects statistical model to repeated CD4 count measurements from HIV-infected individuals from seven sites around the world (including some resource-limited sites). They then used model-derived estimates to apply a mathematical tool for predicting—from a CD4 count taken at the start of treatment, and white blood cell counts and lymphocyte percentage measurements taken later—whether CD4 counts would be above 200 cells/µl (the original threshold recommended for ART initiation) and 350 cells/µl (the current recommended threshold) for up to three years after ART initiation. The tool correctly classified 91.5% of the CD4 cell counts that were below 200 cells/µl in the first year of ART. With this threshold, the potential savings in CD4 testing capacity was 54.3%. With a CD4 count threshold of 350 cells/µl, the potential savings in testing capacity was 34%. The results over a three-year follow-up were similar. When applied to six representative HIV-positive individuals, the tool correctly predicted all the CD4 counts above 200 cells/µl, although some individuals who had a predicted CD4 count of less than 200 cells/µl actually had a CD4 count above this threshold. Thus, none of these individuals would have been exposed to an undetected dangerous CD4 count, but the application of the tool would have saved 57% of the CD4 laboratory tests done during the first year of ART.

What Do These Findings Mean?

These findings support the use of this new tool—the prediction-based classification (PBC) algorithm—for predicting a drop in CD4 count below a clinically meaningful threshold in HIV-infected individuals receiving ART. Further studies are now needed to demonstrate the feasibility, clinical effectiveness, and cost-effectiveness of this approach, to find out whether the tool can be used over extended periods of time, and to investigate whether the accuracy of its predictions can be improved by, for example, adding in periodic CD4 testing. Provided these studies confirm its early promise, the researchers suggest that the PBC algorithm could be used as a “triage” tool to direct available laboratory testing capacity to high-priority individuals (those likely to have a dangerously low CD4 count). By optimizing the use of limited laboratory resources in this and other ways, the PBC algorithm could therefore help to maintain and expand ART programs in low- and middle-income countries.

Additional Information

Please access these web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001207.

Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS

NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment

Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV/AIDS treatment and care and on universal access to AIDS treatment (in English and Spanish)

The World Health Organization provides information about universal access to AIDS treatment (in several languages)

More information about universal access to HIV treatment, prevention, care, and support is available from UNAIDS

Patient stories about living with HIV/AIDS are available through Avert and through the charity website Healthtalkonline

Objective

To determine tuberculosis (TB) incidence rates and risk factors among individuals receiving antiretroviral treatment (ART).

Design

Observational cohort in Johannesburg, South Africa.

Methods

Incident TB was classified as early (<6 months of ART) or late (>6 months of ART) incident TB. CD4 cell counts, viral load (VL), body mass index (BMI) and hemoglobin were measured 6-monthly. Hazard ratios for factors associated with early and late incident TB were assessed using Cox proportional hazards regression.

Results

During 13,416 person-years (py) follow-up, 501 TB cases occurred among 7,536 individuals, corresponding to a 10% risk in the first four years of ART, and an overall incidence rate of 4.2 cases/100 py. The highest incidence rate (21.7 /100 py) was observed in the first 3 months of ART among people with CD4 count below 50 cells/mm3. Low baseline CD4 count, anemia, and low BMI were the strongest risk factor for early incident TB. Low updated CD4 count, low updated BMI, anemia, and high VL on ART were strong risk factors for late incident TB.

Conclusions

Severity of HIV disease and unfavorable response to ART are associated with early and late incident TB, respectively. Early ART initiation and intensified TB screening at ART initiation are crucial to reduce incident TB.

Background

As stavudine remains an important and widely prescribed drug in resource-limited settings, the effect of a reduced dose of stavudine (from 40 mg to 30 mg) on outcomes of highly active antiretroviral therapy (HAART) remains an important public health question.

Methods

We analyzed prospectively collected data from the Themba Lethu Clinic in Johannesburg, South Africa. We assessed the relationship between stavudine dose and six- and/or 12-month outcomes of stavudine substitution, failure to suppress viral load to below 400 copies/ml, development of peripheral neuropathy, lipoatrophy and hyperlactatemia/lactic acidosis. Since individuals with a baseline weight of less than 60 kg were expected to have received the same dose of stavudine throughout the study period, analysis was restricted to individuals who weighed 60 kg or more at baseline. Data were analyzed using logistic regression.

Results

Between 1 April 2004 and 30 September 2009, 3910 patients were initiated on antiretroviral therapy (ART) with a recorded stavudine dose and were included in the analysis. Of these, 2445 (62.5%) received a 40 mg stavudine dose while 1565 (37.5%) received 30 mg. In multivariate analysis, patients receiving a 40 mg dose were more likely to discontinue stavudine use (adjusted odds ratio, OR 1.71; 95% confidence limits, CI 1.13-2.57) than those receiving 30 mg by 12 months on ART. Additionally, patients receiving 40 mg doses of stavudine were more likely to report peripheral neuropathy (OR 3.12; 95% CI 1.86-5.25), lipoatrophy (OR 11.8; 95% CI 3.2-43.8) and hyperlactatemia/lactic acidosis (OR 8.37; 95% CI 3.83-18.29) in the same time period. Failure to suppress HIV viral load within 12 months of HAART initiation was somewhat more common among those given 40 mg doses (OR 1.62; 95% CI 0.88, 2.97) although this result lacked precision. Sensitivity analyses accounting for death and loss to follow up generally supported these estimates.

Conclusions

Lower stavudine dosage is associated with fewer reports of several stavudine-associated adverse events and also a lower risk of stavudine discontinuation within the first year on ART.

Background

Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples.

Methods

In nine countries, we enrolled 1763 couples in which one partner was HIV-1–positive and the other was HIV-1–negative; 54% of the subjects were from Africa, and 50% of infected partners were men. HIV-1–infected subjects with CD4 counts between 350 and 550 cells per cubic millimeter were randomly assigned in a 1:1 ratio to receive antiretroviral therapy either immediately (early therapy) or after a decline in the CD4 count or the onset of HIV-1–related symptoms (delayed therapy). The primary prevention end point was linked HIV-1 transmission in HIV-1–negative partners. The primary clinical end point was the earliest occurrence of pulmonary tuberculosis, severe bacterial infection, a World Health Organization stage 4 event, or death.

Results

As of February 21, 2011, a total of 39 HIV-1 transmissions were observed (incidence rate, 1.2 per 100 person-years; 95% confidence interval [CI], 0.9 to 1.7); of these, 28 were virologically linked to the infected partner (incidence rate, 0.9 per 100 person-years, 95% CI, 0.6 to 1.3). Of the 28 linked transmissions, only 1 occurred in the early-therapy group (hazard ratio, 0.04; 95% CI, 0.01 to 0.27; P<0.001). Subjects receiving early therapy had fewer treatment end points (hazard ratio, 0.59; 95% CI, 0.40 to 0.88; P = 0.01).

Conclusions

The early initiation of antiretroviral therapy reduced rates of sexual transmission of HIV-1 and clinical events, indicating both personal and public health benefits from such therapy.

Background

There has been major improvement in the survival of HIV-1 infected individuals since the South African Government introduced highly active anti-retroviral therapy (HAART) in the public sector in 2004. This has brought new challenges which include the effects of stavudine-related toxicities.

Methods

Prospective analysis of a cohort of 9040 HIV-infected adults who were initiated on HAART at the Themba Lethu Clinic (TLC) in Johannesburg between April 1, 2004 to December 31, 2007, and followed up until June 30, 2008.

Results

Amongst the 9040 study subjects, 8497(94%) were on stavudine based therapy and 5962 (66%) were women. The median baseline CD4 count was 81 cells/mm3 (IQR 29-149). Median follow up on HAART was 19 months (IQR: 9.1-31.6). The proportion of HAART-related side effects for stavudine compared to non-stavudine containing regimens were, respectively: peripheral neuropathy,17.1% vs. 11.2% (p < 0.001); symptomatic hyperlactataemia, 5.7% vs. 2.2% (p < 0.0005); lactic acidosis, 2.5 vs. 1.3% (p = 0.072); lipoatrophy, 7.3% vs. 4.6% (p < 0.05). Among those on stavudine-based regimens, incidence rates for peripheral neuropathy were 12.1 cases/100 person-years (95%CI 7.0-19.5), symptomatic hyperlactataemia 3.6 cases/100 person-years (95%CI 1.2-7.5), lactic acidosis 1.6 cases/100 person-years (95%CI 0.4-5.2) and lipoatrophy 4.6 cases/100 person-years (95%CI 2.1-9.6). Females experienced more toxicity when compared to males in terms of symptomatic hyperlactataemia (p < 0.0001), lactic acidosis (p < 0.0001), lipoatrophy (p < 0.0001) and hypertension (p < 0.05).

Conclusions

We demonstrate significant morbidity associated with stavudine. These data support the latest WHO guidelines, and provide additional evidence for other resource limited HAART rollout programs considering the implementation of non-stavudine based regimens as first line therapy.

Objectives

To compare treatment outcomes by starting CD4 counts using data from the CIPRA-South Africa trial.

Design

Observational cohort study.

Methods

Patients presenting to primary care clinics with CD4 cell counts <350 cells/mm3 were randomized to either doctor- or nurse-managed HIV care and followed for at least two years after ART initiation. Clinical and laboratory outcomes were compared by baseline CD4 count.

Results

812 patients were followed for a median of 27.5 months and 36% initiated with a CD4 count >200. While 10% of patients failed virologically (VF), the risk was nearly double among those with a CD4 ≤200 vs. >200 (12.2% vs. 6.8%). 21 deaths occurred, with a five-fold increased risk for the low CD4 group (3.7% vs. 0.7%). After adjustment, those with a CD4 count ≤200 had twice the risk of death/VF (HR 1.9; 95% CI: 1.1–3.3) and twice the risk of incident tuberculosis (HR: 1.90; 95% CI: 0.89–4.04) as those >200. Those with either a CD4 ≤200 (HR 2.1; 1.2–3.8) or a WHO IV condition (HR 2.9; 0.93–8.8) alone had a two to three-fold increased risk of death/VF vs. those with neither, but those with both conditions had a 4-fold increased risk (HR 3.9; 95% CI: 1.9–8.1). We observed some increased loss to follow-up among those initiating <200 (HR 0.79; 95% CI: 0.50–1.25).

Conclusions

Patients initiating ART with higher CD4 counts had reduced mortality, tuberculosis and less virologic failure than those initiated at lower CD4 counts. Our data support increasing CD4 count eligibility criteria for ART initiation.

Background

Although women of reproductive age are the largest group of HIV-infected individuals in sub-Saharan Africa, little is known about the impact of pregnancy on response to highly active antiretroviral therapy (HAART) in that setting. We examined the effect of incident pregnancy after HAART initiation on virologic response to HAART.

Methods and Findings

We evaluated a prospective clinical cohort of adult women who initiated HAART in Johannesburg, South Africa between 1 April 2004 and 30 September 2009, and followed up until an event, death, transfer, drop-out, or administrative end of follow-up on 31 March 2010. Women over age 45 and women who were pregnant at HAART initiation were excluded from the study; final sample size for analysis was 5,494 women. Main exposure was incident pregnancy, experienced by 541 women; main outcome was virologic failure, defined as a failure to suppress virus to ≤400 copies/ml by six months or virologic rebound >400 copies/ml thereafter. We calculated adjusted hazard ratios using marginal structural Cox proportional hazards models and weighted lifetable analysis to calculate adjusted five-year risk differences. The weighted hazard ratio for the effect of pregnancy on time to virologic failure was 1.34 (95% confidence limit [CL] 1.02, 1.78). Sensitivity analyses generally confirmed these main results.

Conclusions

Incident pregnancy after HAART initiation was associated with modest increases in both relative and absolute risks of virologic failure, although uncontrolled confounding cannot be ruled out. Nonetheless, these results reinforce that family planning is an essential part of care for HIV-positive women in sub-Saharan Africa. More work is needed to confirm these findings and to explore specific etiologic pathways by which such effects may operate.

Background

The degree of immune reconstitution achieved in response to suppressive ART is associated with baseline individual characteristics, such as pre-treatment CD4 count, levels of viral replication, cellular activation, choice of treatment regimen and gender. However, the combined effect of these variables on long-term CD4 recovery remains elusive, and no single variable predicts treatment response. We sought to determine if adiposity and molecules associated with lipid metabolism may affect the response to ART and the degree of subsequent immune reconstitution, and to assess their ability to predict CD4 recovery.

Methods

We studied a cohort of 69 (48 females and 21 males) HIV-infected, treatment-naïve South African subjects initiating antiretroviral treatment (d4T, 3Tc and lopinavir/ritonavir). We collected information at baseline and six months after viral suppression, assessing anthropometric parameters, dual energy X-ray absorptiometry and magnetic resonance imaging scans, serum-based clinical laboratory tests and whole blood-based flow cytometry, and determined their role in predicting the increase in CD4 count in response to ART.

Results

We present evidence that baseline CD4+ T cell count, viral load, CD8+ T cell activation (CD95 expression) and metabolic and anthropometric parameters linked to adiposity (LDL/HDL cholesterol ratio and waist/hip ratio) significantly contribute to variability in the extent of CD4 reconstitution (ΔCD4) after six months of continuous ART.

Conclusions

Our final model accounts for 44% of the variability in CD4+ T cell recovery in virally suppressed individuals, representing a workable predictive model of immune reconstitution.

Summary

Background

Expanded access to combination antiretroviral therapy (ART) in the resource-poor setting is dependent on “task-shifting” from doctors to other health care providers. We compared “doctor-initiated-nurse-monitored” care to the current standard of care, “doctor-initiated-doctor-monitored” ART.

Methods

A randomised strategy trial to determine whether treatment outcomes of “nurse-monitored” ART were non-inferior to “doctor-monitored” ART was conducted at two South African primary-care clinics. HIV-positive individuals with a CD4 count of <350cells/mm3 or WHO stage 3 or 4 disease were eligible. The primary objective was a composite end-point of treatment limiting events, incorporating mortality, viral failure, treatment-limiting toxicities and visit schedule adherence. Intention-to-treat analyses were performed. This study is registered with ClinicalTrials.gov, NCT00255840.

Findings

The hazard ratio for composite failure was 1.09 (95% CI= 0.89-1.33) which lay within the limits for non-inferiority. The analysis was performed on 812 HIV-positive adults with either doctor-(n=408) or nurse-monitored ART (n=404). At baseline 573 (70%) patients were female, 282 (34.7%) had prior AIDS diagnoses and the median CD4 was 164 cells/mm3. After a median follow-up of 24.3 months, deaths (10 vs. 11), virological failures (44 vs. 39), CD4 gain (270 vs. 248 cells/mm3), toxicity failures (68 vs. 66) and program losses (70 vs. 63) were similar in nurse and doctor arms respectively. 371(46%) patients reached an endpoint of treatment failure; 192(47.5%) and 179(43.9%) in the nurse and doctor arms respectively.

Interpretation

Nurse-monitored ART was shown to be non-inferior to doctor-monitored therapy. This study supports task-shifting to appropriately trained nurses for monitoring ART.

Introduction

Increasing EFV dose from 600mg to 800mg daily has been suggested with concomitant RFN, as induction of cytochrome p450 isoenzymes may reduce EFV plasma concentrations

Methods

Individuals from the CIPRA-South Africa cohort taking EFV-based ART with concomitant TB were dosed with either increased-(800mg) or standard-(600mg) dose EFV during TB treatment. After TB therapy all took 600mg EFV. Two mid-dosing interval EFV concentrations were determined from each individual: after 4 weeks of concomitant EFV and RFN therapy, and at least 4 weeks after TB therapy completion. Mid-dosing interval EFV concentrations were compared within individuals using the Wilcoxon signed rank test.

Results

Paired-samples were collected from 72 individuals. 45(63%) were women; median weight 59kg (IQR52-67kg). At ART start median CD4 count was114 cells/mm3 (IQR37-165), median viral load 5.5log (IQR5.1–5.9). 38 (53%) took 800mg EFV during TB treatment and 34(47%) took 600mg. EFV concentrations in the 800mg group were higher with RFN [[2.9mg/L (IQR 1.8–5.6)] than without [2.1mg/L (IQR 1.4–3.0)]], p=0.0003. There was no significant difference in EFV concentrations with RFN [2.4mg/L (IQR1.2–5.1)] or without [2.2 mg/L (IQR 1.4 to 3.7)] in the 600mg group. There was no increase in EFV-linked adverse effects in either group. Proportion virologically suppressed at 48 weeks was similar in both groups.

Conclusion

EFV concentrations were significantly increased in the EFV 800mg group on RFN. There was no significant decrease in EFV concentrations when on RFN in the 600mg group. Dose escalation of EFV 600mg to 800mg is not required during concomitant TB therapy in South Africa.

In this prospective, real-world cohort study nested within a national screening program for tuberculosis, Lesley Scott and colleagues compare the performance of Xpert MTB/RIF on a single sputum sample with different TB sputum detection technologies.

Background

The Xpert MTB/RIF (Cepheid) non-laboratory-based molecular assay has potential to improve the diagnosis of tuberculosis (TB), especially in HIV-infected populations, through increased sensitivity, reduced turnaround time (2 h), and immediate identification of rifampicin (RIF) resistance. In a prospective clinical validation study we compared the performance of Xpert MTB/RIF, MTBDRplus (Hain Lifescience), LightCycler Mycobacterium Detection (LCTB) (Roche), with acid fast bacilli (AFB) smear microscopy and liquid culture on a single sputum specimen.

Methods and Findings

Consecutive adults with suspected TB attending a primary health care clinic in Johannesburg, South Africa, were prospectively enrolled and evaluated for TB according to the guidelines of the National TB Control Programme, including assessment for smear-negative TB by chest X-ray, clinical evaluation, and HIV testing. A single sputum sample underwent routine decontamination, AFB smear microscopy, liquid culture, and phenotypic drug susceptibility testing. Residual sample was batched for molecular testing. For the 311 participants, the HIV prevalence was 70% (n = 215), with 120 (38.5%) culture-positive TB cases. Compared to liquid culture, the sensitivities of all the test methodologies, determined with a limited and potentially underpowered sample size (n = 177), were 59% (47%–71%) for smear microscopy, 76% (64%–85%) for MTBDRplus, 76% (64%–85%) for LCTB, and 86% (76%–93%) for Xpert MTB/RIF, with specificities all >97%. Among HIV+ individuals, the sensitivity of the Xpert MTB/RIF test was 84% (69%–93%), while the other molecular tests had sensitivities reduced by 6%. TB detection among smear-negative, culture-positive samples was 28% (5/18) for MTBDRplus, 22% (4/18) for LCTB, and 61% (11/18) for Xpert MTB/RIF. A few (n = 5) RIF-resistant cases were detected using the phenotypic drug susceptibility testing methodology. Xpert MTB/RIF detected four of these five cases (fifth case not tested) and two additional phenotypically sensitive cases.

Conclusions

The Xpert MTB/RIF test has superior performance for rapid diagnosis of Mycobacterium tuberculosis over existing AFB smear microscopy and other molecular methodologies in an HIV- and TB-endemic region. Its place in the clinical diagnostic algorithm in national health programs needs exploration.

Please see later in the article for the Editors' Summary

Editors' Summary

Background

Tuberculosis (TB)—a contagious bacterial infection that mainly affects the lungs—is a global public health problem. In 2009, 9.4 million people developed TB, and 1.7 million people died from the disease; a quarter of these deaths were in HIV-positive individuals. People who are infected with HIV, the virus that causes AIDS, are particularly susceptible to TB because of their weakened immune system. Consequently, TB is a leading cause of illness and death among people living with HIV. TB is caused by Mycobacterium tuberculosis, which is spread in airborne droplets when people with the disease cough or sneeze. Its characteristic symptoms are a persistent cough, night sweats, and weight loss. Diagnostic tests for TB include sputum smear analysis (the microscopic examination of mucus brought up from the lungs by coughing for the presence of M. tuberculosis) and mycobacterial liquid culture (in which bacteriologists try to grow M. tuberculosis from sputum samples and test its drug sensitivity). TB can usually be cured by taking several powerful drugs daily for at least six months.

Why Was This Study Done?

Mycobacterial culture is a sensitive but slow way to diagnose TB. To halt the disease's spread, it is essential that TB—particularly TB that is resistant to several treatment drugs (multidrug-resistant, or MDR, TB)—is diagnosed quickly. Recently, several nucleic acid amplification technology (NAAT) tests have been developed that rapidly detect M. tuberculosis DNA in patient samples and look for DNA changes that make M. tuberculosis drug-resistant. In December 2010, the World Health Organization (WHO) endorsed Xpert MTB/RIF—an automated DNA test that detects M. tuberculosis and rifampicin resistance (an indicator of MDR TB) within two hours—for the investigation of patients who might have TB, especially in regions where MDR TB and HIV infection are common. TB diagnosis in HIV-positive people can be difficult because they are more likely to have smear-negative TB than HIV-negative individuals. In this prospective study, the researchers compare the performance of Xpert MTB/RIF on a single sputum sample with that of smear microscopy, liquid culture, and two other NAAT tests (MTBDRplus and LightCycler Mycobacterium Detection) in adults who might have TB in Johannesburg (South Africa), a region where many adults are HIV-positive.

What Did the Researchers Do and Find?

The researchers evaluated adults with potential TB attending a primary health care clinic for TB according to national guidelines and determined their HIV status. A sputum sample from 311 participants underwent smear microscopy, liquid culture, and drug susceptibility testing; 177 samples were also tested for TB using NAAT tests. They found that 70% of the participants were HIV-positive and 38.5% had culture-positive TB. Compared to liquid culture, smear microscopy, MTBDRplus, LightCycler Mycobacterium Detection, and Xpert MTB/RIF had sensitivities of 59%, 76%, 76%, and 86%, respectively. That is, assuming that liquid culture detected everyone with TB, Xpert MTB/RIF detected 86% of the cases. The specificity of all the tests compared to liquid culture was greater than 97%. That is, they all had a low false-positive rate. Among people who were HIV-positive, the sensitivity of Xpert MTB/RIF was 84%; the sensitivities of the other NAAT tests were 70%. Moreover, Xpert MTB/RIF detected TB in 61% of smear-negative, culture-positive samples, whereas the other NAATs detected TB in only about a quarter of these samples. Finally, although some TB cases were identified as drug-resistant by one test but drug-sensitive by another, the small number of drug-resistant cases means no firm conclusions can be made about the accuracy of drug resistance determination by the various tests.

What Do These Findings Mean?

Although these findings are likely to be affected by the study's small size, they suggest that Xpert MTB/RIF may provide a more accurate rapid diagnosis of TB than smear microscopy and other currently available NAAT tests in regions where HIV and TB are endemic (i.e., always present). Indeed, the reported accuracy of Xpert MTB/RIF for TB diagnosis—85% sensitivity and 97% specificity—has the potential to save more than 400,000 lives per year. Taken together with the results of other recent studies (including an accompanying article by Lawn et al. that investigates the use of Xpert MTB/RIF for screening for HIV-associated TB and rifampicin resistance), these findings support the WHO recommendation that Xpert MTB/RIF, rather than smear microscopy, should be the initial test in HIV-infected individuals who might have TB.

Additional Information

Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001061.

This study is further discussed in a PLoS Medicine Perspective by Carlton Evans; a related PLoS Medicine Research Article by Lawn et al. is also available

WHO provides information (in several languages) on all aspects of tuberculosis, including general information on tuberculosis diagnostics and specific information on the Xpert MTB/RIF test; further information about WHO's endorsement of Xpert MTB/RIF is included in a recent Strategic and Technical Advisory Group for Tuberculosis report

WHO also provides information about tuberculosis and HIV

The US National Institute of Allergy and Infectious Diseases has detailed information on tuberculosis and HIV/AIDS

The US Centers for Disease Control and Prevention also has information about tuberculosis, including information on the diagnosis of and on tuberculosis and HIV co-infection

Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on HIV-related tuberculosis (in English and Spanish)

Lawrence Long and colleagues report that “down-referring” stable HIV patients from a doctor-managed, hospital-based ART clinic to a nurse-managed primary health facility provides good health outcomes and cost-effective treatment for patients.

Background

To address human resource and infrastructure shortages, resource-constrained countries are being encouraged to shift HIV care to lesser trained care providers and lower level health care facilities. This study evaluated the cost-effectiveness of down-referring stable antiretroviral therapy (ART) patients from a doctor-managed, hospital-based ART clinic to a nurse-managed primary health care facility in Johannesburg, South Africa.

Methods and Findings

Criteria for down-referral were stable ART (≥11 mo), undetectable viral load within the previous 10 mo, CD4>200 cells/mm3, <5% weight loss over the last three visits, and no opportunistic infections. All patients down-referred from the treatment-initiation site to the down-referral site between 1 February 2008 and 1 January 2009 were compared to a matched sample of patients eligible for down-referral but not down-referred. Outcomes were assigned based on vital and health status 12 mo after down-referral eligibility and the average cost per outcome estimated from patient medical record data.

The down-referral site (n = 712) experienced less death and loss to follow up than the treatment-initiation site (n = 2,136) (1.7% versus 6.2%, relative risk = 0.27, 95% CI 0.15–0.49). The average cost per patient-year for those in care and responding at 12 mo was US$492 for down-referred patients and US$551 for patients remaining at the treatment-initiation site (p<0.0001), a savings of 11%. Down-referral was the cost-effective strategy for eligible patients.

Conclusions

Twelve-month outcomes of stable ART patients who are down-referred to a primary health clinic are as good as, or better than, the outcomes of similar patients who are maintained at a hospital-based ART clinic. The cost of treatment with down-referral is lower across all outcomes and would save 11% for patients who remain in care and respond to treatment. These results suggest that this strategy would increase treatment capacity and conserve resources without compromising patient outcomes.

Please see later in the article for the Editors' Summary

Editors' Summary

Background

AIDS has killed more than 25 million people since 1981, and about 33 million people are now infected with HIV, the virus that causes AIDS. Because HIV destroys immune system cells, which leaves infected individuals susceptible to other infections, early in the AIDS epidemic, most HIV-infected people died within ten years of infection. Then, in 1996, antiretroviral therapy (ART), which can keep HIV in check for many years, became available. For people living in developed countries, HIV infection became a chronic condition, but people in developing countries were not so lucky—ART was prohibitively expensive and so a diagnosis of HIV infection remained a death sentence in many regions of the world. In 2003, this situation was declared a global health emergency, and governments, international agencies, and funding bodies began to implement plans to increase ART coverage in developing countries. As a result, nowadays, more than a third of people in low- and middle-income countries who need ART are receiving it.

Why Was This Study Done?

Unfortunately, shortages of human resources in developing countries are impeding progress toward universal ART coverage. In sub-Saharan Africa, for example, where two-thirds of all HIV-positive people live, there are too few doctors to supervise all the ART that is required. Various organizations are therefore encouraging a shift of clinical care responsibilities for people receiving ART from doctors to less highly trained, less expensive, and more numerous members of the clinical workforce. Thus, in South Africa, plans are underway to reduce the role of hospital doctors in ART and to increase the role of primary health clinic nurses. One specific strategy involves “down-referring” patients whose HIV infection is under control (“stable ART patients”) from a doctor-managed, hospital-based ART clinic to a nurse-managed primary health care facility. In this observational study, the researchers investigate the effect of this strategy on treatment outcomes and costs by retrospectively analyzing data collected from a cohort (group) of adult patients initially treated by doctors at the Themba Lethu Clinic in Johannesburg and then down-referred to a nearby primary health clinic where nurses supervised their treatment.

What Did the Researchers Do and Find?

Patients attending the hospital-based ART clinic were invited to transfer to the down-referral site if they had been on ART for at least 11 months and met criteria that indicated that ART was controlling their HIV infection. Each of the 712 stable ART patients who agreed to be down-referred to the primary health clinic was matched to three patients eligible for down-referral but not down-referred (2,136 patients), and clinical outcomes and costs in the patient groups were compared 12 months after down-referral eligibility. At this time point, 1.7% of the down-referred patients had died or had been lost to follow up compared to 6.2% of the patients who continued to receive hospital-based ART. The average cost per patient-year for those in care and responding at 12 months was US$492 for down-referred patients but US$551 for patients remaining at the hospital. Finally, the down-referral site spent US$509 to produce a patient who was in care and responding one year after down-referral on average, whereas the hospital spent US$602 for each responding patient. Thus, the down-referral strategy (nurse-managed care) was more cost-effective than continued hospital treatment (doctor-managed care).

What Do These Findings Mean?

These findings indicate that, at least for this pair of study sites, the 12-month outcomes of stable ART patients who were down-referred to a primary health clinic were as good as or better than the outcomes of similar patients who remained at a hospital-based ART clinic. Moreover, the down-referral strategy saved 11% of costs for patients who remained in care and responded to treatment and appeared to be cost-effective, although additional studies are needed to confirm this last finding. Because this is an observational study (that is, patients eligible for down-referral were not randomly assigned to hospital or primary care facility treatment), it is possible that some unknown factor was responsible for the difference in outcomes between the two patient groups. Nevertheless, these results suggest that the down-referral strategy tested in this study could increase ART capacity and conserve resources without compromising patient outcomes in South Africa and possibly in other resource-limited settings.

Additional Information

Please access these Web sites via the online version of this summary at http://dx.doi.org/journal.pmed.pmed.1001055.

This study is further discussed in a PLoS Medicine Perspective by Ford and Mills

The US National Institute of Allergy and Infectious Diseases provides information on HIV infection and AIDS

HIV InSite has comprehensive information on HIV/AIDS

Information is available from Avert, an international AIDS charity, on many aspects of HIV/AIDS, including information on HIV and AIDS in Africa and on universal access to AIDS treatment (in English and Spanish)

The World Health Organization provides information about universal access to AIDS treatment, including its 2010 progress report (in English, French and Spanish)

Right to Care, a non-profit organization that aims to deliver and support quality clinical services in Southern Africa for the prevention, treatment, and management of HIV, provides information on down-referral

Background

The clinical outcomes of short interruptions of PI-based ART regimens remains undefined.

Methods

A 2-arm non-inferiority trial was conducted on 53 HIV-1 infected South African participants with viral load <50 copies/ml and CD4 T cell count >450 cells/µl on stavudine (or zidovudine), lamivudine and lopinavir/ritonavir. Subjects were randomized to a) sequential 2, 4 and 8-week ART interruptions or b) continuous ART (cART). Primary analysis was based on the proportion of CD4 count >350 cells(c)/ml over 72 weeks. Adherence, HIV-1 drug resistance, and CD4 count rise over time were analyzed as secondary endpoints.

Results

The proportions of CD4 counts >350 cells/µl were 82.12% for the intermittent arm and 93.73 for the cART arm; the difference of 11.95% was above the defined 10% threshold for non-inferiority (upper limit of 97.5% CI, 24.1%; 2-sided CI: −0.16, 23.1). No clinically significant differences in opportunistic infections, adverse events, adherence or viral resistance were noted; after randomization, long-term CD4 rise was observed only in the cART arm.

Conclusion

We are unable to conclude that short PI-based ART interruptions are non-inferior to cART in retention of immune reconstitution; however, short interruptions did not lead to a greater rate of resistance mutations or adverse events than cART suggesting that this regimen may be more forgiving than NNRTIs if interruptions in therapy occur.

Trial Registration

ClinicalTrials.gov NCT00100646

Background

Current guidelines for providing antiretroviral therapy (ART) in South Africa's public sector programme call for switching patients from first-line to second-line treatment upon virologic failure as indicated by two consecutive viral loads above 5000 copies/ml, but without laboratory evidence of viral resistance. We modelled the net cost of adding resistance testing for patients with virological failure and retaining patients without resistance on first-line therapy, rather than switching all failures to second-line therapy.

Methods

Costs were estimated for three scenarios: routine maintenance (standard care without resistance testing, switch all failures to second line); resistance testing (resistance test for patients with failure, switch those with resistance); and limited testing (resistance test for patients with failure in the first three years, switch those with resistance). A Markov model was used to estimate the cost of each arm over five years after first line initiation. Rates of treatment failure, viral resistance and treatment costs were estimated with primary data from a large HIV treatment cohort at a public facility in Johannesburg. Future costs were discounted at 3%.

Results

Virological failure rates over five years were 19.8% in routine maintenance and 20.2% in resistance testing and limited testing; 16.8% and 11.4% of failures in routine and limited testing, respectively, did not have any resistance mutations, resulting in 3.1% and 2.0% fewer patients switching to second-line ART by the end of five years. Treatment costs were estimated at US$526 and $1268 per patient per year on first-line and second-line therapy, respectively; a resistance test cost $242. The total average cost per patient over five years was $2780 in routine maintenance; $2775 in resistance testing; and $2763 in limited testing.

Conclusions

Incorporating resistance testing into treatment guidelines in South Africa is potentially cost-neutral and can identify other reasons for failure, conserve treatment options, and generate information about emerging resistance patterns.

Background

Dosing frequency is an important determinant of regimen effectiveness.

Methods

To compare efficacy of once-daily (QD) versus twice-daily (BID) antiretroviral therapy, we randomized HIV-1 positive, treatment-naïve, patients to lopinavir/ritonavir (LPV/r) 400/100 mg BID (n=160) or LPV/r 800/200 mg QD (n=161), plus either emtricitabine 200 mg QD and extended-release stavudine (d4T-XR) 100 mg QD, or tenofovir 300 mg QD. Randomization was stratified by screening HIV-1 RNA