Prevalence and Sequelae of Cryptococcal Antigenemia in Antiretroviral Therapy-Experienced Populations: An Evaluation of Reflex Cryptococcal Antigen Screening in Botswana.

BACKGROUND: Evidence to inform cryptococcal antigen (CrAg)-screening guidelines among ART-experienced populations is lacking. We performed a study evaluating the utility of reflex CrAg screening in Gaborone, Botswana. METHODS: CD4 count data were collected from the HIV reference laboratory from 2014-2016. CrAg screening was performed on samples with CD4 ≤100 cells/µL beginning January 2015. The proportion of CD4 counts ≤100 cells/µL was determined and the frequency of repeat CrAg testing described. Analyses ascertained the impact of ART status on CrAg prevalence and outcomes, and whether CrAg titers could be used for risk stratification. RESULTS: Overall, 5.6% (3335/59 300) of individuals tested had CD4 ≤100 cells/µL; 2108 samples with CD4 ≤100 cells/µL from 1645 unique patients were CrAg tested. Over half of samples were from ART-experienced individuals: 40.9% (863) on ART and 12.1% (255) defaulters; 22% (463) of CrAg tests were on repeat samples. CrAg prevalence was 4.8% (72/1494; 95% CI, 3.8-6.0%) among outpatients and 21.9% (32/151; 95% CI, 15.3-28.5%) among inpatients. CrAg prevalence rates did not differ by ART status, but 6-month mortality was significantly lower in CrAg-positive individuals on ART at screening. Ten CrAg positives were identified through repeat testing. A CrAg titer cutoff ≥1:80 provided the best discrimination for 6-month survival. CONCLUSIONS: CrAg-positivity rates in an ART-experienced population were comparable to those seen in ART-naive populations. Repeat screening identified individuals who seroconverted to CrAg positivity and were at risk of cryptococcal disease. CrAg titers ≥1:80 can help identify the individuals at highest risk of death for more intensive management.

Evaluation of anatomically designed flocked rectal swabs for molecular detection of enteric pathogens in children admitted to hospital with severe gastroenteritis in Botswana.

Two-hundred eighty matched bulk stool and anatomically designed flocked rectal swab samples were collected from children admitted to the hospital with acute diarrhea in Botswana. Their parents were asked about the acceptability of the swab collection method compared with bulk stool sampling. All samples underwent identical testing with a validated 15-target (9 bacterial, 3 viral, and 3 parasite) commercial multiplex PCR assay. The flocked swabs had a 12% higher yield for bacterial pathogen targets (241 versus 212; P = 0.003) compared with that of stool samples, as well as similar yields for viral targets (110 versus 113; P = 0.701) and parasite targets (59 versus 65; P = 0.345). One hundred sixty-four of the flocked swab-stool pairs were also tested with separate laboratory-developed bacterial and viral multiplex assays, and the flocked rectal swabs had a performance that was similar to that seen with commercial assay testing. Almost all parents/guardians found the swabs acceptable. Flocked rectal swabs significantly facilitate the molecular diagnosis of diarrheal disease in children.

Vitamin D3supplementation in Batswana children and adults with HIV: a pilot double blind randomized controlled trial.

OBJECTIVES: Since vitamin D insufficiency is common worldwide in people with HIV, we explored safety and efficacy of high dose cholecalciferol (D3) in Botswana, and evaluated potential modifiers of serum 25 hydroxy vitamin D change (Δ25D). DESIGN: Prospective randomized double-blind 12-week pilot trial of subjects ages 5.0-50.9 years. METHODS: Sixty subjects randomized within five age groups to either 4000 or 7000 IU per day of D3 and evaluated for vitamin D, parathyroid hormone, HIV, safety and growth status. Efficacy was defined as serum 25 hydroxy vitamin D (25D) ≥32 ng/mL, and safety as no simultaneous elevation of serum calcium and 25D. Also assessed were HIV plasma viral RNA viral load (VL), CD4%, anti-retroviral therapy (ART) regime, and height-adjusted (HAZ), weight-adjusted (WAZ) and Body Mass Index (BMIZ) Z scores. RESULTS: Subjects were 50% male, age (mean±SD) 19.5±11.8 years, CD4% 31.8±10.4, with baseline VL log10 range of <1.4 to 3.8 and VL detectable (>1.4) in 22%. From baseline to 12 weeks, 25D increased from 36±9 ng/ml to 56±18 ng/ml (p<0.0001) and 68% and 90% had 25D ≥32 ng/ml, respectively (p = 0.02). Δ25D was similar by dose. No subjects had simultaneously increased serum calcium and 25D. WAZ and BMIZ improved by 12 weeks (p<0.04). HAZ and CD4% increased and VL decreased in the 7000 IU/d group (p<0.04). Younger (5-13y) and older (30-50y) subjects had greater Δ25D than those 14-29y (26±17 and 28±12 vs. 11±11 ng/ml, respectively, p≤0.001). Δ25D was higher with efavirenz or nevirapine compared to protease inhibitor based treatment (22±12, 27±17, vs. 13±10, respectively, p≤0.03). CONCLUSIONS: In a pilot study in Botswana, 12-week high dose D3 supplementation was safe and improved vitamin D, growth and HIV status; age and ART regimen were significant effect modifiers. TRIAL REGISTRATION: ClinicalTrials.gov NCT02189902.