Wide Variations in Compliance with Tuberculosis Screening Guidelines and Tuberculosis Incidence between Antiretroviral Therapy Facilities - Côte d'Ivoire

Background

In Côte d’Ivoire, tuberculosis (TB) is a common cause of death among HIV-infected antiretroviral therapy (ART) enrollees. Ivorian guidelines recommend screening for TB and initiation of TB treatment before ART initiation. Compliance with these guidelines can help reduce TB-related mortality during ART and possibly nosocomial TB transmission.

Methods and Findings

In a retrospective cohort study among 3,682 randomly selected adults (≥15 years old) starting ART during 2004–2007 at 34 randomly selected facilities, documentation of TB screening completion, prevalence of active TB at ART initiation, and incidence of TB during ART were evaluated. At ART initiation, median age was 36 years, 67% were female, and median CD4 count was 135 cells/μL. Among all 3,682 enrollees, 73 (2%) were on TB treatment at the time of referral to the ART facility. Among the 3,609 not on TB treatment, 1,263 (36%) were documented to receive some TB screening before ART initiation; 21% were screened for cough, 21% for weight loss, 18% for fever, 18% for TB contacts, and 12% for night sweats. Among the 1,263 screened, 111 (11%) were diagnosed with TB and started TB treatment before ART. No associations between patient characteristics and probability of being screened were noted. However, documentation of TB screening completion before ART varied widely by ART facility from 0–100%. TB incidence during ART was 3.0 per 100 person-years but varied widely by ART facility from 0/100 person-year to 13.1/100 person-years.

Conclusions

Screening for TB before ART initiation was poorly documented. Facility-level variations in TB screening documentation suggest facility-level factors, such as investment in training programs, might determine documentation practices. Targeting under-performing ART facilities with improvement activities is needed. Variations among facilities in TB incidence warrant further research. These incidence variations could reflect differences between facilities in TB screening, diagnostic tests, documentation practices, or TB risk possibly related to infection control practices or local community TB incidence.

Detectable HIV Viral Load in Kenya: Data from a Population-Based Survey

Introduction

At the individual level, there is clear evidence that Human Immunodeficiency Virus (HIV) transmission can be substantially reduced by lowering viral load. However there are few data describing population-level HIV viremia especially in high-burden settings with substantial under-diagnosis of HIV infection. The 2^nd Kenya AIDS Indicator Survey (KAIS 2012) provided a unique opportunity to evaluate the impact of antiretroviral therapy (ART) coverage on viremia and to examine the risks for failure to suppress viral replication. We report population-level HIV viral load suppression using data from KAIS 2012.

Methods

Between October 2012 to February 2013, KAIS 2012 surveyed household members, administered questionnaires and drew serum samples to test for HIV and, for those found to be infected with HIV, plasma viral load (PVL) was measured. Our principal outcome was unsuppressed HIV viremia, defined as a PVL ≥ 550 copies/mL. The exposure variables included current treatment with ART, prior history of an HIV diagnosis, and engagement in HIV care. All point estimates were adjusted to account for the KAIS 2012 cluster sampling design and survey non-response.

Results

Overall, 61·2% (95% CI: 56·4–66·1) of HIV-infected Kenyans aged 15–64 years had not achieved virological suppression. The base₁₀ median (interquartile range [IQR]) and mean (95% CI) VL was 4,633 copies/mL (0–51,596) and 81,750 copies/mL (59,366–104,134), respectively. Among 266 persons taking ART, 26.1% (95% CI: 20.0–32.1) had detectable viremia. Non-ART use, younger age, and lack of awareness of HIV status were independently associated with significantly higher odds of detectable viral load. In multivariate analysis for the sub-sample of patients on ART, detectable viremia was independently associated with younger age and sub-optimal adherence to ART.

Discussion

This report adds to the limited data of nationally-representative surveys to report population- level virological suppression. We established heterogeneity across the ten administrative and HIV programmatic regions on levels of detectable viral load. Timely initiation of ART and retention in care are crucial for the elimination of transmission of HIV through sex, needle and syringe use or from mother to child. Further refinement of geospatial mapping of populations with highest risk of transmission is necessary.

Rethinking Dosing Regimen Selection of Piperaquine for Malaria Chemoprevention: A Simulation Study

Background

The combination of short-acting dihydroartemisinin and long-acting piperaquine (DP) is among the first-line therapies for the treatment of uncomplicated Plasmodium falciparum malaria. Population pharmacokinetic models of piperaquine (PQ) based on data from acute treatment of young children can be used to predict exposure profiles of piperaquine under different DP chemoprevention regimens. The purpose of our study was to make such predictions in young children.

Methods

Based on a prior population pharmacokinetic model of PQ in young Ugandan children, we simulated capillary plasma concentration-time profiles (including their variability) of candidate chemoprevention regimens for a reference population of 1–2 year olds weighing at least 11 kg. Candidate regimens that were tested included monthly administration of standard therapeutic doses, bimonthly dosing, and weekly dosing (with and without a loading dose).

Results

Once daily doses of 320 mg for three days (960 mg total) at the beginning of each month are predicted to achieve an average steady-state trough capillary piperaquine concentration of 35 ng/mL, with 60% achieving a level of 30 ng/mL or higher. In contrast, weekly dosing of 320 mg (i.e., 33% higher amount per month) is predicted to approximately double the average steady-state trough concentration, increase the percent of children predicted to achieve 30 ng/mL or higher (94%), while at the same time lowering peak concentrations. Exposure at steady-state, reached at approximately 3 months of multiple dosing, is expected to be approximately 2-fold higher than exposure following initial dosing, due to accumulation. A loading dose improves early exposure, thereby reducing the risk of breakthrough infections at the initiation of chemoprevention.

Conclusions

Once weekly chemoprevention of DP predicts favourable exposures with respect to both trough and peak concentrations. These predictions need to be verified, as well as safety evaluated, in field-based clinical studies of young children. Simulations based on prior knowledge provide a systematic information-driven approach to evaluate candidate DP chemopreventive regimens for future trial designs.