The Costs of Creatinine Testing in the Context of a HIV Pre-Exposure Prophylaxis Demonstration Project in Eswatini.

HIV treatment and prevention as well as other chronic disease care can require regular kidney function assessment based on a creatinine test. To assess the costs of creatinine testing in a public health care system, we conducted activity-based costing during a HIV pre-exposure prophylaxis (PrEP) demonstration project in the Hhohho region of Eswatini. Resource use was assessed by a laboratory technician and valued with government procurement prices, public sector salaries, and own cost estimates. Obtaining a blood sample in a clinic and performing a creatinine test in a high-throughput referral laboratory (> 660,000 blood tests, including > 120,000 creatinine tests, in 2018) were estimated to have cost, on average, $1.98 in 2018. Per test, $1.95 were variable costs ($1.38 personnel, ¢39 consumables, and ¢18 other costs) and ¢2.6 were allocated semi-fixed costs (¢1.1 laboratory equipment, ¢0.85 other, ¢0.45 consumables, and ¢1.3 personnel costs). Simulating different utilization of the laboratory indicated that semi-fixed costs of the laboratory (e.g., equipment purchase or daily calibration of the chemistry analyzer) contributed less than variable costs (e.g., per-test personnel time and test reagents) to the average creatinine test cost when certain minimum test numbers can be maintained. Our findings suggest, first, lower creatinine testing costs than previously used in cost and cost-effectiveness analyses of HIV services and, second, that investment in laboratory equipment imposed a relatively small additional cost on each performed test in the high-throughput referral laboratory.

RESUMEN: El tratamiento y la prevención del VIH, así como el cuidado de otras enfermedades crónicas, pueden requerir una evaluación periódica de la función renal basada en una prueba de creatinina. Para evaluar los costes de las pruebas de creatinina en un sistema de atención sanitaria público, realizamos un cálculo de costes basado en actividades durante un proyecto de demostración de profilaxis preexposición al VIH (PrEP) en la región de Hhohho de Eswatini. El uso de los recursos fue evaluado por un técnico de laboratorio y valorado con los precios de adquisición del gobierno, los salarios del sector público y las estimaciones de costes propias. La obtención de una muestra de sangre en una clínica y la realización de una prueba de creatinina en un laboratorio de referencia de alto rendimiento (> 660.000 pruebas de sangre, incluidas > 120.000 pruebas de creatinina, en 2018) se estimó que habían costado, en promedio, $1,98 en 2018. Por prueba, $1,95 eran costes variables ($1,38 de personal, ¢39 de consumibles y ¢18 de otros costes) y ¢2,6 eran costes semifijos asignados (¢1,1 de equipamiento de laboratorio, ¢0,85 de otros, ¢0,45 de consumibles y ¢1,3 de personal). La simulación de utilización diferente del laboratorio indicó que los costes semifijos del laboratorio (por ejemplo, la compra de equipos o la calibración diaria del analizador químico) contribuyeron menos que los costes variables (por ejemplo, el tiempo del personal por prueba y los reactivos de la prueba) al coste medio de la prueba de creatinina cuando se pueden mantener ciertos números mínimos de pruebas. Nuestros resultados sugieren, en primer lugar, que los costes de las pruebas de creatinina son inferiores a los utilizados anteriormente en los análisis de coste y costo-efectividad de los servicios de VIH y, en segundo lugar, que la inversión en equipos de laboratorio supuso un coste adicional relativamente pequeño en cada prueba realizada en el laboratorio de referencia de alto rendimiento.

Predicting, Diagnosing, and Treating Acute and Early HIV Infection in a Public Sector Facility in Eswatini.

BACKGROUND: The lack of acute and early HIV infection (AEHI) diagnosis and care contributes to high HIV incidence in resource-limited settings. We aimed to assess the yield of AEHI, predict and diagnose AEHI, and describe AEHI care outcomes in a public sector setting in Eswatini. SETTING: This study was conducted in Nhlangano outpatient department from March 2019 to March 2020. METHODS: Adults at risk of AEHI underwent diagnostic testing for AEHI with the quantitative Xpert HIV-1 viral load (VL) assay. AEHI was defined as the detection of HIV-1 VL on Xpert and either an HIV-seronegative or HIV-serodiscordant third-generation antibody-based rapid diagnostic test (RDT) result. First, the cross-sectional analysis obtained the yield of AEHI and established a predictor risk score for the prediction of AEHI using Lasso logistic regression. Second, diagnostic accuracy statistics described the ability of the fourth-generation antibody/p24 antigen-based Alere HIV-Combo RDT to diagnose AEHI (vs Xpert VL testing). Third, we described acute HIV infection care outcomes of AEHI-positive patients using survival analysis. RESULTS: Of 795 HIV-seronegative/HIV-serodiscordant outpatients recruited, 30 (3.8%, 95% confidence interval: 2.6% to 5.3%) had AEHI. The predictor risk score contained several factors (HIV-serodiscordant RDT, women, feeling at risk of HIV, swollen glands, and fatigue) and had sensitivity and specificity of 83.3% and 65.8%, respectively, to predict AEHI. The HIV-Combo RDT had sensitivity and specificity of 86.2% and 99.9%, respectively, to diagnose AEHI. Of 30 AEHI-positive patients, the 1-month cumulative treatment initiation was 74% (95% confidence interval: 57% to 88%), and the 3-month viral suppression (<1000 copies/mL) was 87% (67% to 98%). CONCLUSION: AEHI diagnosis and care seem possible in resource-limited settings.

Poor performance of the determine HIV-1/2 Ag/Ab combo fourth-generation rapid test for detection of acute infections in a National Household Survey in Swaziland.

Fourth-generation HIV rapid tests (RTs) claim to detect both p24 antigen (Ag) and HIV antibodies (Ab) for early identification of acute infections, important for targeting prevention and reducing HIV transmission. In a nationally representative household survey in Swaziland, 18,172 adults, age 18 to 49 years, received home-based HIV rapid testing in 2010 and 2011. Of the 18,172 individuals, 5,822 (32.0%) were Ab positive (Ab(+)) by the Determine HIV-1/2 Ab/Ab combo test, and 5,789 (99.4%) of those were confirmed to be reactive in the Uni-Gold test. Determine combo identified 12 individuals as having acute infections (Ag(+)/Ab negative [Ab(-)]); however, none had detectable HIV-1 RNA and 8 of 12 remained HIV negative at their 6-week follow-up visit (4 were lost to follow-up). All RT-nonreactive samples were pooled and tested by nucleic acid amplification testing (NAAT) to identify acute infections. NAAT identified 13 (0.1%) of the 12,338 HIV antibody-negative specimens as HIV RNA positive, with RNA levels ranging from 300 to >10,000,000 copies/ml. However, none of them were Ag(+) by Determine combo. Follow-up testing of 12 of the 13 NAAT-positive individuals at 6 months demonstrated 12 seroconversions (1 individual was lost to follow-up). Therefore, the Determine combo test had a sensitivity of 0% (95% confidence interval, 0 to 28) and positive predictive value of 0% for the detection of acute infections. The ability of the 4th-generation Determine combo to detect antigen was very poor in Swaziland. Thus, the Determine combo test does not add any value to the current testing algorithm; rather, it adds additional costs and complexity to HIV diagnosis. The detection of acute HIV infections may need to rely on other testing strategies.

Subtype assignment and phylogenetic analysis of HIV type 1 strains in patients from Swaziland.

Aim of this study was to assess HIV-1 subtype distribution and prevalence of transmitted mutations related to antiretroviral drugs in Swaziland. According to the WHO guidelines, 47 plasma samples from naive patients stored at HIV/AIDS National Reference Laboratory in Mbabane between 2002 and 2003, before the introduction of antiretroviral therapy in the country, were studied. HIV-1 RNA was extracted from the plasma samples, RT and protease regions of pol gene were amplified and sequenced. The mutations associated to drug resistance were defined as major or minor on the basis of the recommendations of the International AIDS Society-USA panel. A mutation associated to non nucleoside inhibitors (Y181I) was found in one case showing a prevalence of transmitted drug resistance <5% in Swaziland. No major mutations conferring resistance to protease and nucleoside RT inhibitors were found. Clade assignment was performed by phylogenetic analysis of pol gene. The general time-reversible model of substitution was used to study the phylogenetic relationships between sequences obtained from Swazi patients and sequences from neighbor countries. All patients were found to carry a C subtype. No phylogenetic relationships were detected within Swazi sequences, indicating the absence of epidemiological relationships among patients in study. Although local variants of subtype C have been recently recognized, phylogenetic analysis did not reveal the presence of significant cluster of Swaziland sequences within African variants. This finding may be explained by multiple introduction of C strains.