Long-term virological outcomes, failure and acquired resistance in a large cohort of Ugandan children.

OBJECTIVES: To evaluate long-term virological failure (VF) and drug resistance among HIV-infected Ugandan children on first-line ART. METHODS: In a multicentre prospective cohort study, viral load (VL) and drug resistance mutations (DRMs) were investigated at baseline and 6 monthly intervals in children (age ≤ 12 years). VF (two consecutive VLs >1000 copies/mL or death after 6 months of ART) was defined as early VF (0-24 months of ART) or late VF (25-48 months of ART). An active regimen was defined as partially active if the genotypic susceptibility score (GSS) was <3. RESULTS: Between 2010 and 2011, 316 children were enrolled. Viral suppression was achieved in 75.8%, 71.5%, 72.6% and 69.2% at 12, 24, 36 and 48 months. VF occurred in 111/286 (38.8%), of which 67.6% was early and 32.4% late VF. Early VF was associated with a partially active regimen at baseline (OR 6.0, 95% CI 1.9-18.5), poor adherence (OR 3.1, 95% CI 1.3-7.4) and immunodeficiency (OR 3.3, 95% CI 1.1-10.2). Late VF was associated with age >3 years (OR 2.5, 95% CI 1.0-6.6) and WHO stage 3/4 (OR 4.2, 95% CI 1.4-13.4). Acquired DRMs were detected in 27.0% before 24 months, versus 14.4% after 24 months (P < 0.001). A total of 92.2% of the children with early VF, versus 56.2% with late VF, had a partially active regimen (P < 0.001). CONCLUSIONS: VF rates were high, occurred predominantly in the first 24 months and appeared to increase again in year four. Risk factors and patterns of early VF/DRMs were different from those of late VF/DRMs. Virological control may improve by close monitoring and prompt switching to second-line therapy in the first 24 months. Late VF may be prevented by early start of ART.

High prevalence of virological failure and HIV drug mutations in a first-line cohort of Malawian children.

Background: Drug resistance mutations (DRMs) increasingly jeopardize paediatric HIV programmes in sub-Saharan Africa. As individual monitoring of DRMs and viral loads has limited availability, population data on DRMs are essential to determine first-line susceptibility. Paediatric data from sub-Saharan Africa are scarce and unavailable for Malawi. Objectives: To determine the prevalence of virological failure (VF) and DRMs among ART-naive HIV-infected Malawian children during the first year of first-line ART. Methods: In a prospective cohort of HIV-infected Malawian children, on first-line treatment, children were followed monthly; blood was collected for viral load testing (6 and 12 months) and genotypic resistance testing (12 months). VF was defined as at least one viral load >1000 copies/mL or death after 6 months of ART. DRMs were identified and susceptibility to NRTIs and NNRTIs was scored using the Stanford algorithm and by calculating genotypic susceptibility scores (GSSs). Results: VF occurred in 66% (23/35) of the children during 12 months of follow-up. DRMs were detected in 44% (15/34); all had NNRTI resistance and 12% (4/34) had dual-class NNRTI/NRTI resistance. Reduced susceptibility (DRMs and GSS <3) was seen in 41% (14/34) to their current first-line regimen. High-level resistance was most common for nevirapine [26% (9/34)]. Conclusions: In this first report on VF and DRMs in children on first-line ART in Malawi, the rates of VF and DRMs were alarmingly high. Paediatric HIV programmes in sub-Saharan Africa should emphasize programmatic evaluation of VF and include detection of DRMs to adjust and design adequate first- and second-line regimens and prevent widespread resistance in children.

New cut-off values for ferritin and soluble transferrin receptor for the assessment of iron deficiency in children in a high infection pressure area.

BACKGROUND: Due to the potential risk of iron supplementation in iron replete children, it is important to properly identify children who may require iron supplementation. However, assessment of the iron status has proven to be difficult, especially in children living in areas with high infection pressure (including malaria). AIMS AND METHODS: Biochemical iron markers were compared to bone marrow iron findings in 381 Malawian children with severe anaemia. RESULTS: Soluble transferrin receptor/log ferritin (TfR-F index), using a cut-off of 5.6, best predicted bone marrow iron stores deficiency (sensitivity 74%, specificity 73%, accuracy 73%). In order to improve the diagnostic accuracy of ferritin or sTfR as a stand-alone marker, the normal cut-off value needed to be increased by 810% and 83% respectively. Mean cell haemoglobin concentration (MCHC), using a cut-off of 32.1 g/dl, had a sensitivity of 67% and specificity of 64% for detecting iron stores deficiency. CONCLUSION: TfR-F index incorporated the high sensitivity of sTfR, a proxy for cellular iron need, and the high specificity of ferritin, a proxy for iron stores. In areas with a high infection pressure, the TfR-F index best predicted iron deficiency. However, in settings where diagnostic tests are limited, MCHC may be an acceptable alternative screening test.

Improved method for assessing iron stores in the bone marrow.

BACKGROUND: Bone marrow iron microscopy has been the "gold standard" method of assessing iron deficiency. However, the commonly used method of grading marrow iron remains highly subjective. AIM: To improve the bone marrow grading method by developing a detailed protocol that assesses iron in fragments, in macrophages around fragments and in erythroblasts. METHODS: A descriptive study of marrow aspirates of 303 children (aged 6-60 months) with severe anaemia and 22 controls (children undergoing elective surgery) was conducted at hospitals in southern Malawi (2002-04). RESULTS: Using an intensive marrow iron grading method, 22% and 39% of cases and controls had deficient iron stores, and 40% and 46% had functional iron deficiency, respectively. Further evaluation of the iron status classification by the intensive method showed that functional iron deficiency was associated with significantly increased C-reactive protein concentrations (126.7 (85.6) mg/l), and iron stores deficiency with significantly increased soluble transferrin receptor concentrations (21.7 (12.5) mug/ml). CONCLUSIONS: Iron assessment can be greatly improved by a more intense marrow examination. This provides a useful iron status classification which is of particular importance in areas where there is a high rate of inflammatory conditions.

Aetiology of neonatal sepsis in Blantyre, Malawi: 1996-2001.

AIM: The aim of this retrospective study was to report causes, antibiotic resistance and outcome of neonatal sepsis (often fatal in developing countries) in Malawi. METHODS: All blood and cerebrospinal fluid isolates collected between January 1996 and December 2001 from inpatients aged 0-30 days with suspected sepsis at Queen Elizabeth Central Hospital, Blantyre, Malawi were reviewed. In vitro resistance to antibiotics commonly used in Malawi was assessed. Case fatality rate was analysed with respect to age, bacterial pathogen and infection site. RESULTS: A total of 801 bacteria were isolated from 784 neonates over 6 years-599 isolates from blood and 202 from cerebrospinal fluid. Overall, 54% of bacteria were gram-positive and 46% gram-negative. The commonest causes of neonatal sepsis were group B Streptococcus (17%) and non-typhoidal Salmonella (14%). In vitro antibiotic susceptibility to the first-line antibiotic combination of penicillin and gentamicin was 78% for all isolates, but in vitro sensitivities to gentamicin for Klebsiella spp and non-typhoidal Salmonella were only 33% and 53%, respectively. In-hospital case fatality rate was known for only 301 cases and was high at 48%. Group B Streptococcus was associated with the best outcome. Mortality was significantly higher if presentation was in the 1st week of life or if sepsis was caused by gram-negative bacteria. The causes of neonatal sepsis in this population show a different pattern from other studies in developing countries.