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Background: In developing countries, malnutrition remains a common clinical syndrome at antiretroviral treatment (ART) initiation. Physiologic changes because of malnutrition and during nutritional recovery could affect the pharmacokinetics of antiretroviral drugs., Methods: HIV-infected children admitted with severe acute malnutrition were randomized to early or delayed initiation of lopinavir (LPV)/ritonavir, abacavir and lamivudine using World Health Organization weight band dosage charts. LPV concentrations were measured on day 1 and day 14. Thereafter, patients were followed-up to week 48. The population pharmacokinetics of LPV was described using NONMEM v7.3. Covariates were screened to assess their influence on the pharmacokinetics of LPV, and the relationship between pharmacokinetic variability and treatment outcomes were assessed., Results: Five hundred and two LPV concentrations were collected from 62 pediatric patients 0.1-3.9 years of age (median: 0.9 years). Rifampin-based antituberculosis treatment and "super-boosted" LPV/ritonavir were prescribed in 20 patients. LPV disposition was well described by a one-compartment model with first-order elimination. Neither randomization to early or delayed ART, tuberculosis comedications nor anthropometrical measurements explained the pharmcokinetic variability. Allometrically scaled fat-free mass influenced apparent clearance (CL/F) and volume of distribution (Vd/F). Pharmacokinetic exposure did not correlate with virologic outcomes or death at 12 or 48 weeks., Conclusions: LPV pharmacokinetics was influenced by fat-free mass and not by timing of ART initiation or tuberculosis comedication in severely malnourished HIV-infected children. LPV pharmacokinetics was found to be highly variable and bioavailability greatly reduced, resulting in a high CL estimate in this population. The role of LPV dose adjustment should be further evaluated in severely malnourished children initiating ART.

Background: In a randomized trial comparing nevirapine (NVP)-based versus lopinavir/ritonavir (LPV/r)-based antiretroviral therapy (ART) in HIV-infected children [primary endpoint discontinuation of study treatment for any reason or virologic failure by week 24] aged 2 months to 3 years, we assessed whether clinical, virologic, immunologic and safety outcomes varied by prior single-dose NVP exposure (PrNVP) for prevention of mother-to-child HIV transmission and other covariates., Methods: Efficacy was assessed by time to ART discontinuation or virologic failure, virologic failure/death and death; safety by time to ART discontinuation because of a protocol-defined toxicity and first ≥ grade 3 adverse event; immunology and growth by changes in CD4%, weight/height World Health Organization z-scores from entry to week 48. Cox proportional hazards and linear regression models were used to test whether treatment differences depended on PrNVP exposure and other covariates., Results: Over a median follow up of 48 (PrNVP) and 72 (no PrNVP) weeks, there was no evidence of differential treatment effects by PrNVP exposure or any other covariates. LPV/r-based ART was superior to NVP-based ART for efficacy and safety outcomes; however, those on NVP had larger improvements in CD4%, weight and height z-scores. Lower pretreatment CD4% and higher HIV-1 RNA levels were associated with reduced efficacy, lower pretreatment CD4% with shorter time to ART discontinuation because of a protocol-defined toxicity, and no PrNVP with shorter time to first grade ≥ 3 adverse event., Conclusions: Differences between LPV/r and NVP ART in efficacy, safety, immunologic and growth outcomes did not depend on PrNVP exposure, prior breast-feeding, sex, HIV-1 subtype, age, pretreatment CD4%, HIV-1 RNA or World Health Organization disease stage. This finding should be considered when selecting an ART regimen for young children.

Background: Tuberculous meningitis (TBM) is the most frequent manifestation of central nervous system tuberculosis (TB) and is more common in children than in adults. The diagnosis of TBM in children is difficult because signs and symptoms are vague. Information about drug resistant TB in children is scarce, and there is no published information on drug resistant TBM in children., Methods: This is a retrospective review of medical records of children with culture-confirmed multidrug-resistant tuberculous meningitis (MDR-TBM) at King George V Hospital in Durban, South Africa., Results: Between 1992 and 2003, there were 8 children with MDR-TBM; 6 were HIV infected and 2 were HIV negative. Only one child survived. The diagnosis was made posthumously in almost all the children., Discussion: The changes in the cerebrospinal fluid (CSF) in early TBM can be nonspecific and can change rapidly; therefore, CSF studies should always include culture and susceptibility testing. Factors that contributed to the high mortality were disseminated TB, HIV infection, delay in diagnosis and treatment, the absence of a standardized approach to the management of MDR-TBM and the poor CSF penetration of most MDR-TB drugs. MDR-TB therapy should be considered if there is a history of TB: a MDR-TB contact or a poor clinical response to TB therapy despite adequate adherence to treatment. Early diagnosis is important because TBM in children is often associated with a grave outcome.

Objectives: To determine the vertical transmission rate of HIV-1 infection and to assess the influence of maternal risk factors on transmission in infants born to HIV-1-infected black women in Durban., Design: A prospective, hospital-based cohort study conducted at King Edward VIII hospital, Durban. HIV-1-seropositive women were enrolled into the study, and their infants were followed up at regular intervals from birth to early childhood. The infection status of the children was classified and the transmission rate was computed according to the recommendations of the workshop held in Ghent, Belgium (1992)., Results: The final cohort of 181 infants were classified as 48 infected, 93 not infected and 40 indeterminate. Clearance of maternal antibodies was achieved by 12 months of age in virtually all infants who became seronegative. The intermediate transmission rate was 34% (95% confidence interval, 26 to 42). Deliveries by cesarean section had significantly lower transmission (relative risk, 0.46; 95% confidence interval 0.23 to 0.91). Women with lower hemoglobin concentrations during pregnancy (< 10 g/dl) had an increased risk of transmission (relative risk, 1.99; 95% confidence interval, 1.18 to 3.34). Advanced maternal age, multiparity, positive syphilis serology, duration of ruptured membranes, preterm delivery and breast-feeding were not associated with an increased risk of transmission., Conclusions: This study, the first from South Africa, has confirmed that the rate of vertical transmission of HIV-1 is as high as that reported from most African cohorts. Cesarean sections were protective against transmission, whereas low hemoglobin values values were associated with an increased risk of transmission. Twelve months could be used as the cutoff age for teh diagnosis of vertical infection using antibody tests.

The evolution of human immunodeficiency virus type 1 (HIV-1) antibody titers determined by enzyme-linked immunosorbent assay between birth and 18 months of age was investigated in 118 babies born to HIV-1-seropositive South African mothers. By 18 months 41 (34.7%) children were diagnosed as HIV-1-infected by standard criteria. All 77 uninfected babies cleared maternal antibodies by 15 months; 94.5% of these babies seroreverted by 12 months. By 9 months of age a significant difference (P < 0.05) was noted between antibody decay rates in infected and uninfected children. Of the children subsequently shown to be uninfected, 95.8% demonstrated > or = 50% decay in antibody titers between 6 and 9 months; only 1 in the infected group showed a similar pattern (sensitivity, 97.8%; specificity, 93.8%). The approach of assessing the progression of antibody decay in infected and uninfected babies makes it a feasible and useful tool for estimating vertical transmission rates and diagnosis of perinatal HIV-1 infection earlier than standard practice.