Reconfirming HIV serostatus in three West African Military ART clinics.

BACKGROUND: HIV rapid diagnostic test (RDT) algorithms have been successfully employed worldwide to accelerate critically important HIV testing. Deviations from the algorithm and processing errors have been associated with inaccurate algorithm results. Positive RDT algorithm results should be confirmed prior to HIV clinic enrollment, but compliance varies. We sought to retest HIV status of patients in three West African military HIV clinics. SETTING: Military HIV clinics in Lome, Togo; Freetown, Sierra Leone; and Monrovia, Liberia METHODS: Patients coming for routine HIV clinic visits were approached for enrollment. Consenting participants completed a 15-minute questionnaire and provided blood samples for both national and WHO-recommended HIV RDT algorithms, and HIV ELISA (plus HIV PCR if HIV ELISA negative). RESULTS: In total, 817 participants provided data: 374 in Togo, 360 in Sierra Leone, and 83 in Liberia. One participant from Liberia was HIV-negative (although follow-up testing was positive). Two of 807 participants on antiretroviral treatment (ART) had inconclusive algorithms, while 2 of 10 participants not on ART had algorithms, for 4 total based on the WHO-approved algorithm. Using the national algorithms, only 3 were inconclusive. A substantial proportion of the cohort had taken ART for over 6 years (25-46%, depending on the site). CONCLUSION: HIV RDT retesting in three military HIV clinics did not uncover significant numbers of misclassified HIV patients. There was no significant difference between national and WHO-recommended RDT algorithms, although the study was underpowered to detect a difference. Antiretroviral treatment was not associated with increased rates of inconclusive RDT algorithm results.

The use of dried tube specimens of Plasmodium falciparum in an external quality assessment programme to evaluate health worker performance for malaria rapid diagnostic testing in healthcare centres in Togo.

BACKGROUND: The use of rapid diagnostic tests (RDTs) to diagnose malaria is common in sub-Saharan African laboratories, remote primary health facilities and in the community. Currently, there is a lack of reliable methods to ascertain health worker competency to accurately use RDTs in the testing and diagnosis of malaria. Dried tube specimens (DTS) have been shown to be a consistent and useful method for quality control of malaria RDTs; however, its application in National Quality Management programmes has been limited. METHODS: A Plasmodium falciparum strain was grown in culture and harvested to create DTS of varying parasite density (0, 100, 200, 500 and 1000 parasites/µL). Using the dried tube specimens as quality control material, a proficiency testing (PT) programme was carried out in 80 representative health centres in Togo. Health worker competency for performing malaria RDTs was assessed using five blinded DTS samples, and the DTS were tested in the same manner as a patient sample would be tested by multiple testers per health centre. RESULTS: All the DTS with 100 parasites/µl and 50% of DTS with 200 parasites/µl were classified as non-reactive during the pre-PT quality control step. Therefore, data from these parasite densities were not analysed as part of the PT dataset. PT scores across all 80 facilities and 235 testers was 100% for 0 parasites/µl, 63% for 500 parasites/µl and 93% for 1000 parasites/µl. Overall, 59% of the 80 healthcare centres that participated in the PT programme received a score of 80% or higher on a set of 0, 500 and 1000 parasites/ µl DTS samples. Sixty percent of health workers at these centres recorded correct test results for all three samples. CONCLUSIONS: The use of DTS for a malaria PT programme was the first of its kind ever conducted in Togo. The ease of use and stability of the DTS illustrates that this type of samples can be considered for the assessment of staff competency. The implementation of quality management systems, refresher training and expanded PT at remote testing facilities are essential elements to improve the quality of malaria diagnosis.