Antiretroviral treatment in resource-poor settings: clinical research priorities

Curing HIV: Moving Forward Faster

There is enormous enthusiasm in the scientific community for finding a cure for HIV. Although much remains to be discovered regarding the mechanisms of viral persistence and how it may be disrupted, some assumptions regarding the goals of a cure, applicability to target populations, and what is required of the assays we employ, may lead to missed opportunities and discoveries and hamper the discovery of a product that will safely cure tens of millions of HIV-infected people around the world. The field will benefit from an awareness and critical interrogation of assumptions that may be implicit in their scientific pursuits.

Large unstained cells: a potentially valuable parameter in the assessment of immune activation levels in HIV infection

INTRODUCTION

Chronic immune activation is associated with the accelerated progression of HIV to AIDS; however, affordable markers reflecting this have not yet been determined. The percentage of large unstained cells (%LUCs) is a differential count parameter measured by certain routine hematology analyzers and reflects activated lymphocytes and peroxidase-negative cells. We hypothesized that the %LUCs would be increased in HIV infection and would correlate with markers of immune activation [i.e. CD38 expression on CD8+ T cells (%CD38onCD8) and lipopolysaccharide-binding protein (LBP)] and CD4 counts.

METHODS

In this cross-sectional study, 78 HIV-infected, antiretroviral therapy-naïve adults and 52 uninfected controls were recruited. %CD38onCD8 and CD4 counts were determined by flow cytometry, LBP levels were assessed by immunoassay, and the %LUCs was tested on a Siemens ADVIA 2120.

RESULTS

Significant differences were found between the HIV-infected and control groups for %LUCs (95% CI 2.3-2.7 vs. 1.8-2.2, respectively; p = 0.001), as well as for %CD38onCD8, LBP, and CD4 counts. Furthermore, %LUCs correlated directly with %CD38onCD8 and LBP and inversely with CD4 counts.

CONCLUSION

The %LUCs was significantly increased in this untreated, asymptomatic, HIV-infected group and correlated with markers of immune activation and CD4 counts. Therefore, the %LUCs may be of value in identifying HIV-infected patients at risk of accelerated disease progression.

Global cost modeling analysis of HIV-1 and HCV viral load assays

This review addresses hidden costs associated with the Bayer VERSANT assay, Roche AMPLICOR MONITOR test and COBAS AMPLICOR MONITOR test and how these influence the final per reportable cost to a testing laboratory in resource-rich and -poor countries. An in-depth evaluation and recommendation of the most cost-effective approach for these tests is presented. The analyses demonstrate the need for manufacturers to consider labor and supply costs when marketing a kit in resource-poor countries, noting that marketing strategies need to change. In the absence of any proven monitoring alternative, emphasis is placed on increasing market share to promote significant reduction in kit prices to suit the demands of markets in resource-poor countries. Finally, recommendations are made to improve the overall cost structure of viral load testing. This review is intended as a tool to optimize assay usage in attaining the lowest performance costs by assay and is not to endorse any test, as will become apparent.

Early antiretroviral therapy mortality in resource-limited settings: what can we do about it?

PURPOSE OF REVIEW

Highly active antiretroviral therapy has markedly reduced HIV morbidity and mortality in industrialized countries. Expanded access to the 6.5 million individuals in immediate need of antiretroviral therapy using a public-health-systems approach is now promulgated as an international policy. An approximate 1.6 million individuals have already accessed antiretroviral therapy within programs in resource-poor settings.

RECENT FINDINGS

Early studies from these treatment programs confirm similar virologic and immunologic responses to antiretroviral therapy as were observed earlier in industrialized settings. While medium-term reductions in morbidity and mortality also parallel those reported from Europe and North America, of particular concern is the observation that mortality immediately after starting antiretroviral therapy in resource-poor settings is several-fold higher than that of similar patients initiating antiretroviral therapy in industrialized settings.

SUMMARY

This early mortality is multifactorial and is both a reflection of a very high preantiretroviral therapy mortality and a variety of factors such as comorbid conditions, late presentation, immune restoration disease, together with limited treatment and diagnostic options. Causes of mortality immediately prior to and during early antiretroviral therapy are reviewed and strategies to reduce mortality are identified and discussed.

HIV prevention cost-effectiveness: a systematic review

BACKGROUND

After more than 25 years, public health programs have not been able to sufficiently reduce the number of new HIV infections. Over 7,000 people become infected with HIV every day. Lack of convincing evidence of cost-effectiveness (CE) may be one of the reasons why implementation of effective programs is not occurring at sufficient scale. This paper identifies, summarizes and critiques the CE literature related to HIV-prevention interventions in low- and middle-income countries during 2005-2008.

METHODS

Systematic identification of publications was conducted through several methods: electronic databases, internet search of international organizations and major funding/implementing agencies, and journal browsing. Inclusion criteria included: HIV prevention intervention, year for publication (2005-2008), setting (low- and middle-income countries), and CE estimation (empirical or modeling) using outcomes in terms of cost per HIV infection averted and/or cost per disability-adjusted life year (DALY) or quality-adjusted life year (QALY).

RESULTS

We found 21 distinct studies analyzing the CE of HIV-prevention interventions published in the past four years (2005-2008). Seventeen CE studies analyzed biomedical interventions; only a few dealt with behavioral and environmental/structural interventions. Sixteen studies focused on sub-Saharan Africa, and only a handful on Asia, Latin America and Eastern Europe. Many HIV-prevention interventions are very cost effective in absolute terms (using costs per DALY averted), and also in country-specific relative terms (in cost per DALY measured as percentage of GDP per capita).

CONCLUSION

There are several types of interventions for which CE studies are still not available or insufficient, including surveillance, abstinence, school-based education, universal precautions, prevention for positives and most structural interventions. The sparse CE evidence available is not easily comparable; thus, not very useful for decision making. More than 25 years into the AIDS epidemic and billions of dollars of spending later, there is still much work to be done both on costs and effectiveness to adequately inform HIV prevention planning.

Hormonal contraception and HIV disease progression: a multicountry cohort analysis of the MTCT-Plus Initiative

OBJECTIVE

HIV-infected women need access to safe and effective contraception. Recent animal and human data suggest that hormonal contraception may accelerate HIV disease progression.

METHODS

We compared the incidence of HIV disease progression among antiretroviral therapy-naive women with and without exposure to hormonal contraception at 13 sites in Africa and Asia. Disease progression was defined as becoming eligible for antiretroviral therapy or death.

RESULTS

Between 1 August 2002 and 31 December 2007, the MTCT-Plus programs enrolled 7846 women. In total, 4109 (52%) women met eligibility criteria for this analysis and contributed 5911 person-years of follow-up (median follow-up, 379 days; interquartile range, 121-833). At baseline, 3064 (75%) women reported using either no contraception or a nonhormonal method, whereas 823 (20%) reported using implants/injectables and 222 (5%) reported using oral contraceptive pills. The disease progression outcome was met by 944 (29%) women (rate, 18.3/100 woman-years). Neither implants/injectables (adjusted hazard ratio 1.0, 95% confidence interval 0.8-1.1) nor oral contraceptive pills (adjusted hazard ratio 0.8, 95% confidence interval 0.6-1.1) were associated with disease progression. Treating contraceptive method as a time-varying exposure did not change this negative finding.

CONCLUSION

This multicountry cohort analysis provides some reassurance that hormonal contraception is not associated with HIV disease progression. Further research is needed to address the contraceptive needs of HIV-infected women.

Correlation analysis on total lymphocyte count and CD4 count of HIV-infected patients

OBJECTIVE

To determine the relationship between CD4 count and other blood indices and to explore the prediction of total lymphocyte count (TLC) for CD4 count in HIV-infected patients.

METHODS

Cross-sectional study was performed for the prediction of TLC and other indices for CD4 count, and historical cohort study was performed for the TLC changes as a surrogate for CD4 changes of patients on antiretroviral therapy (ART) to further understanding the utility of TLC changes for AIDS patients' management.

RESULTS

In our cross-sectional study, both TLC and white blood corpuscle count positively correlated to CD4 count, but differed in these patients. For patients on ART, the prediction of TLC for CD4 count is better than that of patient without ART. Further investigation of historical cohort study indicated that, among AIDS patients on highly active antiretroviral therapy, their TLC and haemoglobin changes also positively correlated to CD4 change, with a total correlation coefficient of 0.31 (p < 0.01) and 0.19 (p < 0.01) respectively. The prediction of TLC change for CD4 change differed each time point when patients underwent ART.

CONCLUSIONS

Total lymphocyte count and its change can be used as alternative in conjunction with other indices to CD4 count and its change in the management of HIV-infected individuals in China.

C-reactive protein independently predicts HIV-related outcomes among women and children in a resource-poor setting

OBJECTIVE

To evaluate C-reactive protein (CRP) as a predictor of HIV-related outcomes among women and children in a resource-poor setting.

DESIGN

We measured serum CRP concentration among 606 HIV-infected women, all of whom were not taking highly-active antiretroviral therapy, 3 to 11 months after they gave birth, and assessed relationships of CRP to HIV-related endpoints, including maternal disease progression, mother-to-child transmission of HIV, and maternal and child mortality.

METHODS

We used Cox proportional hazards and regression models adjusted for age, sociodemographic characteristics, anthropometric measurements, hemoglobin, CD4 cell count, HIV viral load, and, for child outcomes, breastfeeding status.

RESULTS

Ninety-four women had a high CRP concentration (> 10 mg/l). During the follow-up, 56 women progressed to WHO stage 4 and 188 died, and a high maternal CRP concentration was associated with a 2.26-fold [95% confidence interval (CI), 1.64-3.12] greater risk of progression to stage 4 or death. Among children, 174 acquired HIV and 116 died by age 2 years, and a high maternal CRP concentration was associated with a 3.03-fold (95% CI, 1.85-4.96) greater risk of child mortality. In multivariate analyses among adults, a high maternal CRP concentration was associated with a 1.55-fold (95% CI, 1.08-2.23) greater risk of progression to stage 4 or death. A maternal CRP concentration was not significantly associated with mother-to-child transmission of HIV.

CONCLUSIONS

A high maternal CRP concentration independently predicts HIV disease progression, maternal mortality, and child mortality in a resource-poor setting. C-reactive protein may be an important and inexpensive prognostic indicator for HIV-infected women and their children.

International perspectives, progress, and future challenges of paediatric HIV infection

Paediatric HIV infection is a growing health challenge worldwide, with an estimated 1500 new infections every day. In developed countries, well established prevention programmes keep mother-to-child transmission rates at less than 2%. However, in developing countries, where transmission rates are 25-40%, interventions are available to only 5-10% of women. Children with untreated natural infection progress rapidly to disease, especially in resource-poor settings where mortality is greater than 50% by 2 years of age. As in adult infection, antiretroviral therapy has the potential to rewrite the natural history of HIV, but is accessible only to a small number of children needing therapy. We focus on the clinical and immunological features of HIV that are specific to paediatric infection, and the formidable challenges ahead to ensure that all children worldwide have access to interventions that have proved successful in developed countries.

Healthcare utilization of patients accessing an African national treatment program

Background

The roll-out of antiretroviral therapy (ART) in Africa will have significant resource implications arising from its impact on demand for healthcare services. Existing studies of healthcare utilization on HAART have been conducted in the developed world, where HAART is commenced when HIV illness is less advanced.

Methods

This paper describes healthcare utilization from program entry by treatment-naïve patients in a peri-urban settlement in South Africa. Treatment criteria included a CD4 cell count <200 cells/μl or an AIDS-defining illness. Data on health service utilization were collected retrospectively from the primary-care clinic and secondary and tertiary referral hospitals. Hospital visits were reviewed to determine the clinical reason for each visit.

Results

212 patients were followed for a median of 490 days. Outpatient visits per 100 patient years of observation (PYO), excluding scheduled primary-care follow-up, fell from 596 immediately prior to ART to 334 in the first 48 weeks on therapy and 245 thereafter. Total inpatient time fell from 2,549 days per 100 PYO pre-ART to 476 in the first 48 weeks on therapy and 73 thereafter. This fall in healthcare utilization occurred at every level of care. The greatest causes of utilization were tuberculosis, cryptococcal meningitis, HIV-related neoplasms and adverse reactions to stavudine. After 48 weeks on ART demand reverted to primarily non-HIV-related causes.

Conclusion

Utilization of both inpatient and outpatient hospital services fell significantly after commencement of ART for South African patients in the public sector, with inpatient demand falling fastest. Earlier initiation might reduce early on-ART utilization rates.

Simple Pediatric AIDS Severity Score (PASS): a pediatric severity score for resource-limited settings

BACKGROUND

A multidimensional pediatric AIDS severity score (PASS) has been developed for severity adjustment and as a predictive model for mortality in a pediatric HIV-infected population. While the prognostic value of PASS is relevant in the US setting, there is a need to develop a simpler model of PASS for use in resource-limited settings where CD4% values and HIV RNA levels may not be available to assess prognosis and guide treatment decisions.

METHODS

A Simple PASS model was developed including baseline weight percentile, WHO stage, symptoms, a general health rating, total lymphocyte count, packed-cell volume, and albumin measures from 1178 perinatally HIV-infected children enrolled into a prospective cohort study (PACTG 219). This prognostic model was then validated among 952 perinatally HIV-infected children enrolled in other PACTG research studies at the same sites. Survival estimates and Hazard Ratios (HR) were obtained using the Kaplan-Meier method and proportional hazards models, respectively. The predictive ability of the models was determined using Harrell's "C" statistic.

RESULTS

Of the clinical measures and assays considered in this study, weight percentile, WHO stage, symptomatology, general health rating, total lymphocyte count, packed-cell volume, and albumin were found to be predictive of mortality. The simple PASS model including only the simple clinical measures and assays was found to be predictive of mortality (C statistic = 0.852). Its discriminative ability for mortality was comparable to a model consisting of the Simple PASS plus CD4% (C statistic = 0.871).

CONCLUSION

The Simple PASS scoring system provides a reasonable alternative to CD4% values and HIV viral-load levels to assess prognosis and guide decisions about antiretroviral therapy initiation in resource-limited settings.

Short-term risk of AIDS or death in people infected with HIV-1 before antiretroviral therapy in South Africa: a longitudinal study

BACKGROUND

In sub-Saharan Africa, data for short-term risk of AIDS or death, which might inform decisions about when to start antiretroviral therapy (ART), are scarce. Our aim was to investigate these risks in patients who had no access to ART or who were given zidovudine alone.

METHODS

6-month risks (%) of death, AIDS, and combined risk of AIDS and death (AIDS/death) were calculated according to CD4-cell count category of less than 200 cells per microL, 200-350 cells per microL, or greater than 350 cells per microL, stratified by WHO clinical stages 1 and 2 combined, 3, or 4 in untreated patients (n=1399) seeking care in tertiary public-sector HIV clinics before widespread availability of ART in Cape Town, South Africa.

FINDINGS

Risk of death for WHO stages 1 and 2 was 3.5% for those with less than 200 cells per microL, 2.8% for 200-350 cells per microL, and 1.2% for greater than 350 cells per microL. The corresponding rates for WHO stage 3 were 10.8%, 4.3%, and 4.9% and for stage 4, 22.2%, 10.3%, and 13.8%. 52% (90) of deaths took place in patients without AIDS. 6-month risk of AIDS for WHO stages 1 and 2 was 3.5% for those with less than 200 cells per microL, 1.6% for 200-350 cells per microL, and zero for greater than 350 cells per microL. The corresponding rates for those with WHO stage 3 disease were 17.4%, 7.0%, and 2.2%.

INTERPRETATION

In this study, risk of AIDS in patients with a CD4-cell count of less than 200 cells per microL or greater than 350 cells per microL was similar to that previously reported from European cohorts, but was 1.9 times greater for those with CD4-cell counts of between 200 and 350 cells per microL. The high death rate before development of AIDS and a high risk of AIDS in those with CD4-cell counts of 200-350 cells per microL indicate that delay in initiation of ART is associated with increased morbidity and mortality. These findings might help to amend criteria for start of ART in resource-limited settings.

Monitoring HIV treatment in developing countries

Laboratory monitoring of antiretroviral therapy helps limit resistance but is currently not feasible in developing countries. Alternative short term approaches are needed

Assessment of the efficacy of total lymphocyte counts as predictors of AIDS defining infections in HIV-1 infected people

BACKGROUND

The CD4 count is a dominant prognostic and predictive factor in HIV infection. This study assessed the utility of the total lymphocyte count (TLC) in place of the CD4 count to predict the development of AIDS defining opportunistic infections (ADOI).

METHODS

The Chelsea and Westminster cohort was used to identify those people with a first episode of an ADOI. Corresponding CD4 and TLCs were recorded before diagnosis or at the time of first prescribing prophylaxis; patients without an AIDS defining opportunistic infection were defined as being at "risk" and receiver operating characteristic (ROC) curves were used to display the results of sensitivity and the false positive error rate of total lymphocyte and CD4 count groups.

RESULTS

A significant linear correlation was seen between the log(10) CD4 count and log(10) TLC (Pearson's correlation coefficient = 0.70, p<0.001). The finer cut off value for TLC where false positive error rate is minimum and sensitivity maximum was 1500-2000 cells/mm(3). Patients with TLC 1000-1500 cells/mm(3) were estimated to be at 40% increased risk of developing an ADOI. The cut off value for CD4 counts measured 200 cells/mm(3) above which the risk developing an ADOI decreased. Patients with a CD4 count of 150-200 cells/mm(3) were at a 34% increased risk of developing an ADOI. The area under the ROC curve for TLC was 10% lower than that for CD4 count.

CONCLUSIONS

The TLC is minimally less reliable than the CD4 count as a predictor of ADOIs. In the absence of expensive equipment for CD4 measurement, the TLC is a useful test.

Use of total lymphocyte count for informing when to start antiretroviral therapy in HIV-infected children: a meta-analysis of longitudinal data

BACKGROUND

Total lymphocyte count has been proposed as an alternative to the percentage of CD4+ T-cells to indicate when antiretroviral therapy should be started in children with HIV in resource-poor settings. We aimed to assess thresholds of total lymphocyte count at which antiretroviral therapy should be considered, and compared monitoring of total lymphocyte count with monitoring of CD4-cell percentage.

METHODS

Longitudinal data on 3917 children with HIV infection were pooled from observational and randomised studies in Europe and the USA. The 12-month risks of death and AIDS by most recent total lymphocyte count and age were estimated by parametric survival models, based on measurements before antiretroviral therapy or during zidovudine monotherapy. Risks were derived and compared at thresholds of total lymphocyte count and CD4-cell percentage for starting antiretroviral therapy recommended in WHO 2003 guidelines.

FINDINGS

Total lymphocyte count was a powerful predictor of the risk of disease progression despite a weak correlation with CD4-cell percentage (r=0.08-0.19 dependent on age). For children older than 2 years, the 12-month risk of death and AIDS increased sharply at values less than 1500-2000 cells per muL, with little trend at higher values. Younger children had higher risks and total lymphocyte count was less prognostic. Mortality risk was substantially higher at thresholds of total lymphocyte count recommended by WHO than at corresponding thresholds of CD4-cell percentage. When the markers were compared at the threshold values at which mortality risks were about equal, total lymphocyte count was as effective as CD4-cell percentage for identifying children before death, but resulted in an earlier start of antiretroviral therapy.

INTERPRETATION

In this population, total lymphocyte count was a strong predictor of short-term disease progression, being only marginally less predictive than CD4-cell percentage. Confirmatory studies in resource-poor settings are needed to identify the most cost-effective markers to guide initiation of antiretroviral therapy.

Body mass index at time of HIV diagnosis: a strong and independent predictor of survival

BACKGROUND

Identification of basic prognostic indicators of HIV infection is essential before widespread antiretroviral therapy can be implemented in low-technology settings. This study assessed how well body mass index (BMI:kg/m2) predicts survival.

METHODS

BMI within 3 months of HIV diagnosis was obtained from 1657 patients aged > or = 15 years, recruited in a seroprevalent clinical cohort in The Gambia since 1992 and followed up at least once. Baseline CD4+ counts and clinical assessment at time of diagnosis were done.

RESULTS

The mortality hazard ratio (HR) of those with a baseline BMI <18 compared with those with a baseline BMI > or = 18 was 3.4 (95% CI, 3.0-3.9). The median survival time of those presenting with a BMI <16 was 0.8 years, in contrast to a median survival of 8.9 years for those with a baseline BMI > or = 22. Baseline BMI <18 remained a highly significant independent predictor of mortality after adjustment for age, sex, co-trimoxazole prophylaxis, tuberculosis, reported wasting at diagnosis, and baseline CD4+ cell count (adjusted HR = 2.5, 95% CI 2.0-3.0). Sensitivity and specificity of baseline BMI <18 was comparable to that of a CD4+ count <200 in predicting mortality within 6 months of diagnosis.

DISCUSSION

BMI at diagnosis is a strong, independent predictor of survival in HIV-infected patients in West Africa. In the absence of sophisticated clinical and laboratory support, BMI may also prove a useful guide for deciding when to initiate antiretroviral therapy.

A pilot study of once-daily antiretroviral therapy integrated with tuberculosis directly observed therapy in a resource-limited setting

To determine the feasibility and effectiveness of integrating highly active antiretroviral therapy (HAART) into existing tuberculosis directly observed therapy (TB/DOT) programs, we performed a pilot study in an urban TB clinic in South Africa. Patients with smear-positive pulmonary TB were offered HIV counseling and testing. Twenty HIV-positive patients received once-daily didanosine (400 mg) plus lamivudine (300 mg) plus efavirenz (600 mg) administered concomitantly with standard TB therapy Monday to Friday and self-administered on weekends. After completing TB therapy, patients were referred to an HIV clinic for continued treatment. At baseline, patients had a mean CD4 count of 230 cells/mm(3) (range: 24-499 cells/mm(3)) and a mean viral load of 5.75 log(10) (range: 3.81-7.53 log(10)). Seventeen completed combined standard TB and HIV therapy; 16 of 20 (80%) patients enrolled and 15 of 17 (88%) patients completing standard TB therapy achieved a viral load <50 copies/mL and mean CD4 count increase of 148 cells/mm(3). TB was cured in 17 of 20 (85%) enrolled patients and 17 of 19 (89%) patients with drug-sensitive TB. Treatment was well tolerated, with minimal gastrointestinal, hepatic, skin, or neurologic toxicity. The project was well accepted and integrated into the daily TB clinic functions. This pilot study demonstrates that TB/DOT programs can be feasible and effective sites for HIV identification and the introduction and monitoring of a once-daily HAART regimen in resource-limited settings.

Antiretroviral therapy in resource-poor countries: illusions and realities

The prospects for antiretroviral therapy in resource-poor settings have changed recently and considerably with the availability of generic drugs, the drastic price reduction of brand-name drugs, and the simplification of treatment. However, such cost reductions, although allowing the implementation of large-scale donor programs, have yet to render treatment accessible and possible in the general population. Successfully providing HIV treatment in high-prevalence/high-caseload countries may require that we redefine the problem as a public health mass therapy program rather than a multiplication of clinical situations. The public health goal cannot simply be the reduction of morbidity and mortality for those treated but must be the reduction in morbidity and mortality for the many, that is, at a population level.

Behavior Assessment of Blood Donors Facing the Risk of HIV Infection, Abidjan, Côte D'Ivoire, 2001-2002

Despite precautions taken to guarantee blood safety, in the National Blood Transfusion Center (CNTS) of Abidjan, about 30 regular blood donors are detected with HIV seroconversion each year, two-thirds of them men. A survey through face-to-face interviews was carried out at the CNTS of Abidjan from September 2001 to March 2002 among HIV-positive and HIV-negative regular blood donors, informed about their serologic status. HIV-negative regular blood donors informed about their serologic status since a median time of 67 months (n = 50) disclosed more risky behaviors such as multiple sexual partners (68%) than HIV-positive blood donors informed about their status (n = 112) since a median time of 35 months (41%) (P < 0.001). Condoms were systematically used by 17% of HIV-negative blood donors and 55% of HIV-positive blood donors (P < 0.001). Enhanced counseling and awareness could reduce in the future the number of cases of seroconversion among regular blood donors and improve their subsequent behavior. Blood donors who have unprotected sex with partners of unknown HIV serologic status and especially with casual partners are strongly exposed to HIV transmission and should be discouraged to continue giving blood, after adequate counseling.

Antiretroviral treatment in resource-poor settings: public health research priorities

Many countries in Africa are planning to provide highly active antiretroviral therapy (HAART) to millions of people with acquired immune deficiency syndrome. This will be a highly complex therapy programme. Physician-based models of care adapted from industrialized countries will not succeed in providing treatment to the majority of those who need it in resource-constrained settings. A high priority is to identify care models for Africa that will increase coverage of HAART safely and effectively: key issues are (i) whether nursing staff or non-clinically qualified staff can take the major role in the treatment programme and reduce the workload of physicians, (ii) whether treatment and monitoring can be delivered through peripheral health centres or through home visits and achieve better adherence and be more cost-effective than delivery at hospitals and (iii) which clinical algorithms used by nursing or non-clinically qualified staff will be effective for screening, diagnosing and managing treatment-related side-effects and medical problems being incurred. Many current ART support programmes are making little or no investment in research, but answering important questions on delivery of HAART will be essential if HAART programmes are to be successful in African nations with a high burden of human immunodeficiency virus infection.

Highly active antiretroviral therapies among HIV-1-infected children in Abidjan, Côte d'Ivoire

OBJECTIVE

To describe the effect of highly active antiretroviral therapy (HAART) in HIV-1-infected African children.

STUDY DESIGN

Observational ANRS 1244 cohort of 159 children with HIV between October 2000 and September 2002; 78 children (49%) receiving HAART were followed for a mean duration of 21 months.

METHODS

Weight-for-age Z-scores (WAZ), height-for-age Z-scores (HAZ), CD4 lymphocyte count and HIV-1 RNA viral load were measured before initiating HAART and every 6 months during treatment. Probability of survival and incidences of pneumonia and acute diarrhoea were calculated.

RESULTS

Values before and after 620 days of HAART, respectively, were -2.02 and -1.39 for mean WAZ, (P < 0.01); -2.03 and -1.83 for mean HAZ (P = 0.51); 0.07 and 0.025/child-month (P = 0.002) for incidence of pneumonia; and 0.12 and 0.048/child-month for incidence of acute diarrhoea (P < 0.001) (incidence changes statistically significant only in children < 6.5 years). Overall, the probability of survival under HAART was 72.8% at 24 months for children with < 5% CD4 cells versus 97.8% in children with >/= 5% (P < 0.01). At HAART initiation, median viral load and CD4 cell percentage were 5.41 log10 copies/ml and 7.7%, respectively. After 756 days of HAART, on average, 50% of patients had undetectable viral load and 10% had 2.4-3.0 log10 copies/ml. The median CD4 percentage was 22.5%.

CONCLUSION

In resource-limited setting, it is possible to use HAART to treat African children. This treatment appears as effective as in developed countries.

Transmission of HIV-1 drug resistance

BACKGROUND

The use of highly-active anti-retroviral therapy (HAART) for treating HIV infections is increasing. Recent studies have demonstrated that HAART is improving both the length and quality of life in HIV-infected patients. Resistant strains of HIV arise when drug adherence is poor. This can lead to the transmission of drug-resistant strains of HIV to susceptible individuals. This can lead to suboptimal first-line therapy, if the resistance profile of the transmitted virus is unknown.

OBJECTIVES

To review the mechanisms of how drug resistance arises; the methods used to characterise drug resistance; the problems arising with compliance leading to the development of drug-resistant HIV strains; the evidence for the incidence, prevalence and trends in the transmission of resistant HIV strains in different risk groups; and the evidence of suboptimal response to first-line therapy where transmission of a resistant HIV strain has occurred. On the basis of this, a case is presented for the routine resistance testing of all newly diagnosed HIV-infected individuals.

STUDY DESIGN

Literature review.

RESULTS AND CONCLUSIONS

There is evidence, though limited at present, that transmission of drug-resistant HIV strains can lead to suboptimal response to first-line therapy in newly diagnosed HIV-infected individuals. As the use of HAART can only increase in the future, and compliance will always be a problem in such HAART-treated patients, baseline resistance testing should become a routine part of their management.

Changes in Total Lymphocyte Count as a Surrogate for Changes in CD4 Count Following Initiation of HAART: Implications for Monitoring in Resource-Limited Settings

BACKGROUND

A major obstacle to the administration of highly active antiretroviral therapy (HAART) in resource-limited settings is the high cost of CD4 count testing. The total lymphocyte count (TLC) has been proposed as a surrogate marker to monitor immune response to therapy.

OBJECTIVE

To assess, in a developed country setting, the capability and clinical utility of TLC change as a surrogate marker for CD4 count change in monitoring patients on HAART.

METHODS

Longitudinal co-variation between changes in TLC and concomitant changes in CD4 count following the initiation of HAART was examined using a retrospective cohort study of 126 HIV-positive patients attending The Miriam Hospital, Brown University, Providence, RI. Analyses included evaluation of the direction of TLC change as a marker for direction of CD4 change, using sensitivity and specificity; evaluation of absolute change in TLC as a marker for benchmark changes in CD4 (> or =50 over 6 months, > or =100 over 12 months), using receiver-operator characteristic (ROC) curves; and a regression model of change in TLC as a function of change in CD4, to understand within-individual variation of longitudinal TLC measures.

RESULTS

In the first 24 months of HAART, the sensitivity of a TLC increase as a marker for CD4 count increase over the same time period ranged from 86-94%, and the specificity ranged from 80-85%. The median change in TLC among patients with a CD4 count rise of > or =100 cells/mm at 1 year of HAART was +766 cells/mm while that of patients with a CD4 count rise of <100 cells/m was +100 cells/mm. The area under the corresponding ROC curve was 0.89, suggesting that change in TLC discriminates well between those with 1-year CD4 change of > or =100 vs. those with change <+100. From a regression analysis, we found that mean change in TLC per 1 cell/mm change in CD4 count was 7.3 (SE 1.2, P < 0.001). The degree of this association varied from individual to individual but was positive for all individuals.

CONCLUSIONS

Within the first 2 years of HAART, the direction of change in TLC appears to be a strong marker for direction of concomitant change in CD4 count (sensitivity 86-94% and specificity 80-85%, depending on length of interval). Positive and negative predictive values depend on the proportion of CD4 changes that are positive. In this cohort, that proportion is 87.9%, which yields high positive predictive value (96-98%) but lower negative predictive value (43-63%). Findings from the regression model suggest that taking multiple measurements of TLC at more frequent intervals may reduce variability and potentially improve predictive accuracy.

Scaling-up treatment for HIV/AIDS: lessons learned from multidrug-resistant tuberculosis

The UN has launched an initiative to place 3 million people in developing countries on antiretroviral AIDS treatment by end 2005 (the 3 by 5 target). Lessons for HIV/AIDS treatment scale-up emerge from recent experience with multidrug-resistant tuberculosis. Expansion of treatment for multidrug-resistant tuberculosis through the multipartner mechanism known as the Green Light Committee (GLC) has enabled gains in areas relevant to 3 by 5, including policy development, drug procurement, rational use of drugs, and the strengthening of health systems. The successes of the GLC and the obstacles it has encountered provide insights for building sustainable HIV/AIDS treatment programmes.

Alternatives to HIV-1 RNA concentration and CD4 count to predict mortality in HIV-1-infected children in resource-poor settings

Cheaper, simpler alternatives to CD4 lymphocyte count and HIV-1 RNA detection for assessing the prognosis of HIV-1 infection are needed for resource-poor settings. However, little is known about the predictive value of alternative assays, in particular in children. We assessed the prognostic value of total lymphocyte count, immune complex-dissociated p24 antigen, white blood cell count, packed-cell volume (haematocrit), and serum albumin for mortality in 376 HIV-1-infected, mainly African-American or Hispanic children enrolled during March, 1988 to January, 1991. In a Cox proportional hazards model, including all assay-alternatives to CD4 and RNA, total lymphocyte count (p<0.0001) and serum albumin (p=0.0107) independently predicted mortality. Further assessment of these markers is warranted in resource-poor settings.

Highly active antiretroviral therapy in resource-poor settings: the experience of Médecins Sans Frontières

We describe the short-term results of highly active antiretroviral therapy (HAART) in seven projects in low and middle income countries. A total of 743 adults were included, and clinical, immunological and virological responses were analysed. At 6 months, outcomes were similar to those observed in western countries, and the probability of remaining on treatment was 94%. The challenge now is to extend access to HAART to the millions in urgent need.

What can oncologists learn from HIV?

Developments in HIV-related medicine have significant implications for the practice of oncology. Although HIV is a relatively new discipline within medicine, the identification and therapeutic targeting of HIV has been rapid. Furthermore, political lobbying has sculpted scientific research and patient care. Rational drug design has reduced morbidity and mortality to such an extent that the development of predictive surrogate endpoints has been necessary to enable randomised assessments of new protocols to continue. These studies now include the routine detection of resistance to tailor specific therapies to the patient. The involvement of affected communities in dynamically modelled studies have shown the efficacy of new, preventive strategies and debates about such approaches have improved the standard of care. In this review, we discuss what oncologists can learn from the HIV epidemic.