Normal Clinical Laboratory Ranges by Age and Sex, and Impact on Study Screening Outcomes in Rural Mali.

The interpretation of a laboratory test result requires an appropriate reference range established in healthy subjects, and normal ranges may vary by factors such as geographic region, sex, and age. We examined hematological and clinical chemistry parameters in healthy residents at two rural vaccine trial sites: Bancoumana and Doneguebougou in Mali, West Africa. During screening of clinical studies in 2018 and 2019, peripheral blood samples from 1,192 apparently healthy individuals age 6 months to 82 years were analyzed at a laboratory accredited by the College of American Pathologists for a complete blood count, and creatinine and/or alanine aminotransferase levels. Based on manufacturers' reference range values, which are currently used in Malian clinical laboratories, abnormal values were common in this healthy population. In fact, 30.4% of adult participants had abnormal neutrophil levels and 19.8% had abnormal hemoglobin levels. Differences by sex were observed in those who were older, but not in those younger than 10 years, for several parameters, including hemoglobin, platelet, and absolute neutrophil counts in hematology, and creatinine in biochemistry. The site-specific reference intervals we report can be used in malaria vaccine clinical trials and other interventional studies, as well as in routine clinical care, to identify abnormalities in hematological and biochemical parameters among healthy Malian trial participants.

The effect of sample handling on cross sectional HIV incidence testing results.

OBJECTIVE(S): To determine if mishandling prior to testing would make a sample from a chronically infected subject appear recently infected when tested by cross-sectional HIV incidence assays. METHODS: Serum samples from 31 subjects with chronic HIV infection were tested. Samples were subjected to different handling conditions, including incubation at 4 °C, 25 °C and 37 °C, for 1, 3, 7 or 15 days prior to testing. Samples were also subjected to 1,3, 7 and 15 freeze-thaw cycles prior to testing. Samples were tested using the BED capture enzyme immuno assay (BED-CEIA), Vironostika-less sensitive (V-LS), and an avidity assay using the Genetic Systems HIV-1/HIV-2 plus O EIA (avidity assay). RESULTS: Compared to the sample that was not subjected to any mishandling conditions, for the BED-CEIA, V-LS and avidity assay, there was no significant change in test results for samples incubated at 4 °C or 25 °C prior to testing. No impact on test results occurred after 15 freeze-thaw cycles. A decrease in assay results was observed when samples were held for 3 days or longer at 37 °C prior to testing. CONCLUSIONS: Samples can be subjected up to 15 freeze-thaw cycles without affecting the results the BED-CEIA, Vironostika-LS, or avidity assays. Storing samples at 4 °C or 25 °C for up to fifteen days prior to testing had no impact on test results. However, storing samples at 37°C for three or more days did affect results obtained with these assays.

Frequency of long-term nonprogressors in HIV-1 seroconverters From Rakai Uganda.

OBJECTIVE: Studies on long-term nonprogressors (LTNP) have been conducted in the USA and Europe. This study examined the frequency of LTNPs and HIV controllers among 637 HIV-1 seroconverters in rural Uganda. DESIGN AND METHODS: LTNPs were defined as being infected for more than 7 years with a CD4 T-cell count above 600 cells per microliter, and HIV controllers as having undetectable viral loads on 3 separate occasions without antiretroviral treatment. HIV-1 viral load and subtype distribution between LTNP and non-LTNP populations were determined. RESULTS: Of the HIV seroconverters, 9.1% (58/637) were LTNPs and 1.4% (9/637) were HIV controllers. LTNPs had a significantly lower viral load at set point than non-LTNP participants (P < 0.001). The Kaplan-Meier joint probability of surviving to 7 years with a CD4 count >600 was 19.2%. Individuals who survived 7 years had a significantly higher frequency of HIV-1 subtype A (P < 0.05), but seroconverters infected with HIV-1A did not have a significantly higher probability of becoming an LTNP. CONCLUSIONS: The frequency of LTNPs appears to be relatively high in Uganda and it may be important to take this into account when designing studies of viral pathogenesis and performing HIV vaccine trials in sub-Saharan Africa.

Microbial translocation, the innate cytokine response, and HIV-1 disease progression in Africa.

Reports from the United States have demonstrated that elevated markers of microbial translocation from the gut may be found in chronic and advanced HIV-1 infection and are associated with an increase in immune activation. However, this phenomenon's role in HIV-1 disease in Africa is unknown. This study examined the longitudinal relationship between microbial translocation and circulating inflammatory cytokine responses in a cohort of people with varying rates of HIV-1 disease progression in Rakai, Uganda. Multiple markers for microbial translocation (lipopolysaccharide, endotoxin antibody, and sCD14) did not change significantly during HIV-1 disease progression. Moreover, circulating immunoreactive cytokine levels either decreased or remained virtually unchanged throughout disease progression. These data suggest that microbial translocation and its subsequent inflammatory immune response do not have a causal relationship with HIV-1 disease progression in Africa.

Selection of HIV variants with signature genotypic characteristics during heterosexual transmission.

BACKGROUND: Newly infected subjects acquire a limited number of human immunodeficiency virus type 1 (HIV-1) variants with specific genotypic and phenotypic features from the array of viruses present in a chronically infected transmitting partner. METHODS: We examined HIV-1 envelope sequences from the earliest available serum sample after HIV-1 acquisition in 13 newly infected subjects and from their epidemiologically linked HIV-1-infected heterosexual partner. Samples from both members were collected on the same day in the Rakai Community Cohort Study. RESULTS: Ten couples were infected with subtype D HIV-1, and 3 pairs had subtype A HIV-1. Newly infected subjects acquired a subset of the viruses that were circulating in the transmitting partner; transmitted variants had less diversity and divergence and were more closely related to the ancestral sequences. The majority of signature amino acid differences among donor and recipient sequences were in and immediately following the V3 loop. Envelopes from recipients were significantly shorter and had a lower V3 charge than envelopes from donors, but there was no significant difference in the number of potential N-linked glycosylation sites. CONCLUSION: A minority subset of HIV-1 variants with signature genotypes is favored for transmission in this population.

Improved performance of enzyme-linked immunosorbent assays and the effect of human immunodeficiency virus coinfection on the serologic detection of herpes simplex virus type 2 in Rakai, Uganda.

Ugandan subjects (820) were tested by Focus HerpeSelect enzyme-linked immunosorbent assay (ELISA), Kalon herpes simplex virus type 2 ELISA, and BioKit rapid test, and the results were compared to those of Western blotting. Higher-than-standard-index cutoff values gave optimal sensitivity and specificity. Kalon ELISA was the optimal assay when an index value of 1.5 was used (sensitivity, 91.7%; specificity, 92.4%).