HIV-1 drug resistance testing is essential for heavily-treated patients switching from first- to second-line regimens in resource-limited settings: evidence from routine clinical practice in Cameroon.

BACKGROUND: With the phase-out of stavudine (d4T), change to first-line regimens with zidovudine (AZT) or tenofovir (TDF) in resource-limited settings (RLS) might increase risks of cross-resistance to nucleos(t) ide reverse transcriptase inhibitors (NRTI). This would restrict the scope of switching to the World Health Organisation (WHO)-recommended standard second-line combinations (SLC) without HIV drug resistance (HIVDR)-testing in routine clinical practice. METHODS: An observational study was conducted among 101 Cameroonian patients (55.4% male, median [IQR] age 34 [10-41] years) failing first-line antiretroviral therapy (ART) in 2016, and stratified into three groups according to NRTIs exposure: exposure to both thymidine analogues AZT "and" D4T (group-A, n = 55); exposure to both TDF and AZT "or" D4T (group-B, n = 22); exposure solely to D4T (group-C, n = 24). Protease-reverse transcriptase HIVDR was interpreted using the HIVdb penalty scores (≥60: high-resistance; 20-59: intermediate-resistance; < 20: susceptible). The acceptable threshold for potential-efficacy was set at 80%. RESULTS: The median [IQR] CD4, viral RNA, and time on ART, were respectively 129 [29-466] cells/µl, 71,630 [19,041-368,000] copies/ml, and 4 [2-5] years. Overall HIVDR-level was 89.11% (90/101), with 83.2% harbouring M184 V (high-level 3TC/FTC-resistance) and only 1.98% (2/101) major HIVDR-mutations to ritonavir-boosted protease-inhibitors (PI/r). Thymidine-analogue mutations (TAMs)-1 [T215FY (46.53%), M41 L (22.77%), L210 W (8.91%)], with cross-resistance to AZT and TDF, were higher compared to TAMs-2 [D67N (21.78%), K70R (19.80%), K219QE (18.81%)]. As expected, K65R was related with TDF-exposure: 0% (0/55) in group-A, 22.72% (5/22) group-B, 4.17% (1/24) group-C (p = 0.0013). The potential-efficacy of AZT vs. TDF was respectively 43.64% (24/55) vs. 70.91% (39/55) in group-A (p = 0.0038); 63.64% (14/22) vs. 68.28% (15/22) in group-B (p = 1.0000); and 37.50% (9/24) vs. 83.33% (20/24) in group-C (p = 0.0032). CRF02_AG was the prevailing subtype (63.40%), followed by CRF11.cpx (8.91%), A1 (7.92%), G (5.94%); without any significant effect of the subtype-distribution on HIVDR (92.2% in CRF02_AG vs. 83.8% in non-AG; p = 0.204). CONCLUSION: First-line ART-failure exhibits high-level NRTI-resistance, with potential lower-efficacy of AZT compared to TDF. Significantly, using our 80% efficacy-threshold, only patients without NRTI-substitution on first-line could effectively switch to SLC following the WHO-approach. Patients with multiple NRTI-substitutions (exposed to both thymidine-analogues and TDF) on first-line ART would require HIVDR-testing to select active NRTIs for SLC.

Using weight-for-age for predicting wasted children in Cameroon.

INTRODUCTION: The equipment for taking body weights (scales) are more frequently used in Cameroon health centres than measuring boards for heights. Even when the later exist there are some difficulties inherent in their qualities; thus the height measurement is not always available or accurate. Our objective for this study was to construct statistical models for predicting wasting from weight-for-age. METHODS: 3742 children aged 0 to 59 months were enrolled in a cross-sectional household survey (2004 Cameroon Demographic and Health Surveys (DHS)) covering the entire Cameroon national territory. RESULTS: There were highly significant association between underweight and wasting. For all discriminant statistical methods used, the test error rates (using an independent testing sample) were less than 5%; the Area Under Curve (AUC) using the Receiver Operating Characteristic (ROC) was 0.86. CONCLUSION: The study showed that weight-for-age can be used for accurately classifying a child whose wasting status is unknown. The result is useful in Cameroon as too often the height measurements may not be feasible, thus the need for estimating wasted children. This study provides baseline information that will help to design a preliminary pivotal study on an immediate nutrition intervention for acute undernutrition. Its complications that could lead to morbidity and mortality can be greatly reduced or set up a management control strategy that will go a long way in reducing the cost of health care in Cameroon.