Joep J. van Oosterhout

The public health approach to identify antiretroviral therapy failure: high-level nucleoside reverse transcriptase inhibitor resistance among Malawians failing first-line antiretroviral therapy

Background:Over 150 000 Malawians have started antiretroviral therapy (ART), in which first-line therapy is stavudine/lamivudine/nevirapine. We evaluated drug resistance patterns among patients failing first-line ART on the basis of clinical or immunological criteria in Lilongwe and Blantyre, Malawi. Methods:Patients meeting the definition of ART failure (new or progressive stage 4 condition, CD4 cell count decline more than 30%, CD4 cell count less than that before treatment) from January 2006 to July 2007 were evaluated. Among those with HIV RNA of more than 1000 copies/ml, genotyping was performed. For complex genotype patterns, phenotyping was performed. Results:Ninety-six confirmed ART failure patients were identified. Median (interquartile range) CD4 cell count, log10 HIV-1 RNA, and duration on ART were 68 cells/μl (23–174), 4.72 copies/ml (4.26–5.16), and 36.5 months (26.6–49.8), respectively. Ninety-three percent of samples had nonnucleoside reverse transcriptase inhibitor mutations, and 81% had the M184V mutation. The most frequent pattern included M184V and nonnucleoside reverse transcriptase inhibitor mutations along with at least one thymidine analog mutation (56%). Twenty-three percent of patients acquired the K70E or K65R mutations associated with tenofovir resistance; 17% of the patients had pan-nucleoside resistance that corresponded to K65R or K70E and additional resistance mutations, most commonly the 151 complex. Emergence of the K65R and K70E mutations was associated with CD4 cell count of less than 100 cells/μl (odds ratio 6.1) and inversely with the use of zidovudine (odds ratio 0.18). Phenotypic susceptibility data indicated that the nucleoside reverse transcriptase inhibitor backbone with the highest activity for subsequent therapy was zidovudine/lamivudine/tenofovir, followed by lamivudine/tenofovir, and then abacavir/didanosine. Conclusion:When clinical and CD4 cell count criteria are used to monitor first-line ART failure, extensive nucleoside reverse transcriptase inhibitor and nonnucleoside reverse transcriptase inhibitor resistance emerges, with most patients having resistance profiles that markedly compromise the activity of second-line ART.

Retention in care under universal antiretroviral therapy for HIV-infected pregnant and breastfeeding women ('Option B+') in Malawi

Objective:To explore the levels and determinants of loss to follow-up (LTF) under universal lifelong antiretroviral therapy (ART) for pregnant and breastfeeding women (‘Option B+’) in Malawi. Design, setting, and participants:We examined retention in care, from the date of ART initiation up to 6 months, for women in the Option B+ program. We analysed nationwide facility-level data on women who started ART at 540 facilities (n = 21 939), as well as individual-level data on patients who started ART at 19 large facilities (n = 11 534). Results:Of the women who started ART under Option B+ (n = 21 939), 17% appeared to be lost to follow-up 6 months after ART initiation. Most losses occurred in the first 3 months of therapy. Option B+ patients who started therapy during pregnancy were five times more likely than women who started ART in WHO stage 3/4 or with a CD4+ cell count 350 cells/&mgr;l or less, to never return after their initial clinic visit [odds ratio (OR) 5.0, 95% confidence interval (CI) 4.2–6.1]. Option B+ patients who started therapy while breastfeeding were twice as likely to miss their first follow-up visit (OR 2.2, 95% CI 1.8–2.8). LTF was highest in pregnant Option B+ patients who began ART at large clinics on the day they were diagnosed with HIV. LTF varied considerably between facilities, ranging from 0 to 58%. Conclusion:Decreasing LTF will improve the effectiveness of the Option B+ approach. Tailored interventions, like community or family-based models of care could improve its effectiveness.

Prevention of mother-to-child transmission of HIV and the health-related Millennium Development Goals: time for a public health approach

This article focuses on prevention of mother-to-child transmission (PMTCT) of HIV particularly in Malawi and discusses how the country is preparing to revise its policies for PMTCT of HIV and for antiretroviral therapy (ART) in response to WHOs 2010 guidelines. The authors propose offering all HIV-infected pregnant women lifelong ART which they see as a more feasible alternative to WHOs guidelines in addition to being more ethical. The article also describes the various benefits of their proposed plan and estimates the results and costs associated.

Evaluation of antiretroviral therapy results in a resource-poor setting in Blantyre, Malawi

Objective  To evaluate treatment results of the paying antiretroviral therapy (ART) clinic of Queen Elizabeth Central Hospital, a large public and teaching hospital in Blantyre, Malawi. The only ART was a fixed drug combination of stavudine, lamivudine and nevirapine.

Dysregulated humoral immunity to nontyphoidal Salmonella in HIV-infected African adults.

HIV and Salmonella HIV-positive individuals who are infected with nontyphoidal strains of Salmonella enterica often succumb to high morbidity and mortality. Why this is the case is unknown. MacLennan et al. (p. 508; see the Perspective by Moir and Fauci) have uncovered a dysregulated antibody response to Salmonella that is the likely culprit. Sera from HIV-infected individuals do a poor job of killing S. Typhimurium, despite surprisingly elevated antibody titers. Experiments showed that HIV-infected serum inhibited the power of normal serum to kill Salmonella. Inhibition was specific to antibodies against lipopolysaccharide (LPS), a component of the cell wall of Salmonella. Hence, HIV-infected sera was able to kill Salmonella strains lacking LPS, and removing LPS immunoglobulin G from infected sera permitted Salmonella killing. Thus, not only does HIV cause defects in cell-mediated immunity but it also seems to impair humoral immunity, with severe consequences for multiple infections. Abnormal antibody responses produced in HIV-infected individuals are ineffective at clearing food-poisoning bacteria. Nontyphoidal Salmonellae are a major cause of life-threatening bacteremia among HIV-infected individuals. Although cell-mediated immunity controls intracellular infection, antibodies protect against Salmonella bacteremia. We report that high-titer antibodies specific for Salmonella lipopolysaccharide (LPS) are associated with a lack of Salmonella-killing in HIV-infected African adults. Killing was restored by genetically shortening LPS from the target Salmonella or removing LPS-specific antibodies from serum. Complement-mediated killing of Salmonella by healthy serum is shown to be induced specifically by antibodies against outer membrane proteins. This killing is lost when excess antibody against Salmonella LPS is added. Thus, our study indicates that impaired immunity against nontyphoidal Salmonella bacteremia in HIV infection results from excess inhibitory antibodies against Salmonella LPS, whereas serum killing of Salmonella is induced by antibodies against outer membrane proteins.

Assessment of second-line antiretroviral regimens for HIV therapy in Africa

BACKGROUND The efficacy and toxic effects of nucleoside reverse-transcriptase inhibitors (NRTIs) are uncertain when these agents are used with a protease inhibitor in second-line therapy for human immunodeficiency virus (HIV) infection in resource-limited settings. Removing the NRTIs or replacing them with raltegravir may provide a benefit. METHODS In this open-label trial in sub-Saharan Africa, we randomly assigned 1277 adults and adolescents with HIV infection and first-line treatment failure to receive a ritonavir-boosted protease inhibitor (lopinavir-ritonavir) plus clinician-selected NRTIs (NRTI group, 426 patients), a protease inhibitor plus raltegravir in a superiority comparison (raltegravir group, 433 patients), or protease-inhibitor monotherapy after 12 weeks of induction therapy with raltegravir in a noninferiority comparison (monotherapy group, 418 patients). The primary composite end point, good HIV disease control, was defined as survival with no new World Health Organization stage 4 events, a CD4+ count of more than 250 cells per cubic millimeter, and a viral load of less than 10,000 copies per milliliter or 10,000 copies or more with no protease resistance mutations at week 96 and was analyzed with the use of imputation of data (≤4%). RESULTS Good HIV disease control was achieved in 60% of the patients (mean, 255 patients) in the NRTI group, 64% of the patients (mean, 277) in the raltegravir group (P=0.21 for the comparison with the NRTI group; superiority of raltegravir not shown), and 55% of the patients (mean, 232) in the monotherapy group (noninferiority of monotherapy not shown, based on a 10-percentage-point margin). There was no significant difference in rates of grade 3 or 4 adverse events among the three groups (P=0.82). The viral load was less than 400 copies per milliliter in 86% of patients in the NRTI group, 86% in the raltegravir group (P=0.97), and 61% in the monotherapy group (P<0.001). CONCLUSIONS When given with a protease inhibitor in second-line therapy, NRTIs retained substantial virologic activity without evidence of increased toxicity, and there was no advantage to replacing them with raltegravir. Virologic control was inferior with protease-inhibitor monotherapy. (Funded by European and Developing Countries Clinical Trials Partnership and others; EARNEST Current Controlled Trials number, ISRCTN37737787, and ClinicalTrials.gov number, NCT00988039.).

Using touchscreen electronic medical record systems to support and monitor national scale-up of antiretroviral therapy in Malawi.

Gerry Douglas and colleagues describe the rationale and their experience with scaling up electronic health records in six antiretroviral treatment sites in Malawi.

Impact of HIV-Associated Immunosuppression on Malaria Infection and Disease in Malawi

BACKGROUND Human immunodeficiency virus (HIV) infection and malaria coexist in much of Africa. Previous studies differ in their findings on the interactions between the 2 infections. METHODS Adults living with HIV infection in Blantyre, Malawi, were enrolled in a longitudinal observational study from September 2002 to August 2004. Malaria blood smears were obtained monthly and for any illness suggestive of malaria. Complete evaluations of all illness episodes were conducted, regardless of malaria smear results. RESULTS The incidence of clinical malaria episodes was higher in participants with CD4 cell counts <200 cells/mm3 than in those with CD4 cell counts >500 cells/mm3. The trend was preserved when increasingly specific definitions of malaria disease were used. The prevalence of malaria infection was not associated with CD4 cell count. In per-visit analysis, lower CD4 cell counts were associated with higher incidences of pneumonia, sepsis, and tuberculosis but not of malaria. Severe malaria was rare, with only 3 cases in 591 person-years of observation. Parasite density and CD4 cell count were independent risk factors for fever. CONCLUSIONS Profoundly immunosuppressed adults with HIV infection require more-frequent treatment for uncomplicated malaria, but malaria infection and disease are less strongly associated with HIV-associated immunosuppression than are other opportunistic infections. Where malaria is common, the high incidence of fever found among immunosuppressed adults may lead to misclassification of illness episodes as malaria.

Supplementary feeding with either ready-to-use fortified spread or corn-soy blend in wasted adults starting antiretroviral therapy in Malawi: randomised, investigator blinded, controlled trial.

Objective To investigate the effect of two different food supplements on body mass index (BMI) in wasted Malawian adults with HIV who were starting antiretroviral therapy. Design Randomised, investigator blinded, controlled trial. Setting Large, public clinic associated with a referral hospital in Blantyre, Malawi. Participants 491 adults with BMI <18.5. Interventions Ready-to-use fortified spread (n=245) or corn-soy blend (n=246). Main outcome measures Primary outcomes: changes in BMI and fat-free body mass after 3.5 months. Secondary outcomes: survival, CD4 count, HIV viral load, quality of life, and adherence to antiretroviral therapy. Results The mean BMI at enrolment was 16.5. After 14 weeks, patients receiving fortified spread had a greater increase in BMI and fat-free body mass than those receiving corn-soy blend: 2.2 (SD 1.9) v 1.7 (SD 1.6) (difference 0.5, 95% confidence interval 0.2 to 0.8), and 2.9 (SD 3.2) v 2.2 (SD 3.0) kg (difference 0.7 kg, 0.2 to 1.2 kg), respectively. The mortality rate was 27% for those receiving fortified spread and 26% for those receiving corn-soy blend. No significant differences in the CD4 count, HIV viral load, assessment of quality of life, or adherence to antiretroviral therapy were noted between the two groups. Conclusion Supplementary feeding with fortified spread resulted in a greater increase in BMI and lean body mass than feeding with corn-soy blend. Trial registration Current Controlled Trials ISRCTN67515515.

Diagnosis of antiretroviral therapy failure in Malawi: poor performance of clinical and immunological WHO criteria.

Objectives  In antiretroviral therapy (ART) scale‐up programmes in sub‐Saharan Africa viral load monitoring is not recommended. We wanted to study the impact of only using clinical and immunological monitoring on the diagnosis of virological ART failure under routine circumstances.