Verification of dried blood spot as a sample type for HIV viral load and early infant diagnosis on Hologic Panther in Zambia.

OBJECTIVE: Zambia has embarked on improving the diagnostic capacity by setting up high throughput and accurate machines in the testing process and introduction of dried blood spot (DBS) as a sample type. This was a cross sectional study to verify dried blood spot as a sample type for HIV viral load and early infant diagnosis (EID) on Hologic Panther platform and Evaluate the analytical performance (precision, linearity and measurement of uncertainty) of the Hologic Panther. RESULTS: The specificity and sensitivity of EID performance of Aptima Quant Dx assay on Hologic panther machine against the gold standard machine COBAS Taqman (CAP/CTM) was 100% with an overall agreement of 100%. The quantitative HIV Viral Load (VL) accuracy had a positive correlation of (0.96) obtained against the gold standard (plasma samples) run on COBAS4800 platform. Analytical performance of the Hologic panther machine was evaluated; Precision low positive repeatability 3.50154 and within lab 2.268915 at mean 2.88 concentration and precision high positive repeatability 1.116955 and within lab 2.010677 at mean 5.09 concentration were obtained confirming manufacturers claims. Uncertainty of measurement for this study was found to be ± 71 copies/ml. Linearity studies were determined and all points were within acceptable limits. We therefore recommend DBS as a sample type alternative to plasma for the estimation of HIV-1 viral load and EID diagnosis on the Hologic panther machine.

Prevalence of low high-density lipoprotein among young adults receiving antiretroviral therapy in Zambia: An opportunity to consider non-communicable diseases in resource-limited settings.

BACKGROUND: With the introduction of effective antiretroviral therapy (ART), people living with HIV (PLWH) are surviving longer and are at risk for developing metabolic abnormalities that contribute to cardiovascular disease (CVD). In Sub-Saharan Africa (SSA), there is a paucity of epidemiological data on lipid profiles among young adults receiving ART. This study aimed to estimate the prevalence of low high-density lipoprotein cholesterol (HDL-c), a cardioprotective lipid class, and whether it differed by age among adults on ART in Livingstone, Zambia. METHODS: From April to December 2019, we conducted a cross-sectional study of 597 PLWH [n = 58 aged 18-24 years (young adults); n = 539 aged ≥25 years (adults)] on ART for ≥6 months. Data collected included demographic and lifestyle information, anthropometrics, viral load (VL), CD4 count, blood pressure, lipid profiles and fasting/random blood glucose. Clinical measures were defined as: low HDL-c [<1.0 mmol/L for men, <1.3 for women], increased waist circumference (WC) [≥94 cm for men, ≥80 cm for women], high triglycerides (TG) [≥1.7 mmol/l], and virological failure (VF) [VL ≥1000 copies/µl]. We used logistic regression to examine the association between age and low HDL-c after adjusting for multiple variables. RESULTS: Among the young adults, 60% (35/58) were women, median (25th, 75th percentile) age 21 years (18, 23), and median time on ART 116 months (60, 144). Among adults, 63% (342/539) were women, median age 46 years (40, 53) and median time on ART 108 months (60, 144). Young adults had a lower CD4 count compared to adults (median, 492 vs. 568 cells/µL, p = 0.010) and higher prevalence of VF (29% vs. 17%, p = 0.016). In young adults, prevalence of low HDL-c was significantly higher than in adults (63 vs. 38%, p<0.001). A high proportion of young adults (75%) and adults (58%) with low HDL-c were on dolutegravir (DTG)-based ART regimens. After adjusting for sex, duration on ART, WC, body mass index, ART regimen, VF, CD4 count, low density lipoprotein cholesterol, blood pressure and smoking, young adults were significantly more likely than adults to have low HDL-c (odds ratio 2.93; 95% confidence interval 1.46-5.86). CONCLUSION: Low HDL-c is highly prevalent among young adult with HIV in SSA independent of other risk factors for metabolic derangements. Lipid abnormalities among young PLWH may contribute to the early development of cardiovascular diseases in this population. This highlights the need to consider low HDL-c in the quest to reduce CVD risk among young adults on ART in SSA.