Evaluation of diagnostic microbiology capacity and barriers in testing for HIV and TB at peripheral hospital-based laboratories in Oyo-state, Nigeria

Background: Tuberculosis (TB) and human immunodeficiency virus (HIV) are two interrelated infectious diseases that continue to threaten public health in several parts of the world. In Nigeria, a maximum of 52,000 people died from HIV and TB in 2017 which suggests that the two diseases are still a burden on the nation's health. This study sought to evaluate the diagnostic microbiology capacity and barriers in testing for HIV and TB at peripheral government-owned secondary hospital-based laboratories in Oyo State, Nigeria. Methods and materials: This study used a descriptive cross-sectional design to evaluate 17 government-owned secondary hospital-based laboratories in Oyo State. A WHO laboratory assessment tool was used to evaluate the study laboratories. Diagnostic capacity was measured on a scale of 100-point in which scores ≤49% were rated low, fair (50–79%), and good (≥80%). A score of 0, 50 and 100 were assigned to no, partial and yes responses respectively and the average score was calculated. Results: Evaluation of diagnostic capacity showed that 11 (64.7%) and 6 (35.3%) of the laboratories had ‘low’ and ‘fair’ capacity respectively to test sputum or cerebrospinal fluid for TB. For HIV, 14 (82.4%) of the laboratories had ‘low capacity’ and 3 (17.6%) had ‘fair capacity’ to test serum for HIV antigen and blood for viral load. Analysis of the type of assay performed at the laboratories indicated that 9 (52.9%) of the laboratories could carry out acid-fast bacilli (AFB) smear using Ziehl-Neelsen stain, 8 (47.1%) Rhodamine/Auramine stain and no laboratory could perform AFB culture and sensitivity. Seven (41.2%) of the laboratories could carry out a serological test for HIV and 3 (17.6%) could test blood for viral load. More than 50% of the laboratories reported that unavailable testing kits/reagents for HIV/TB and lack of culture facilities for AFB were the diagnostic barriers responsible for the ‘low’ and ‘fair’ capacity observed in the laboratories. Conclusion: The low capacity of laboratories in this state underscores the need for interventions to improve the supply of testing kits, reagents and culture facilities which will enhance prompt detection of HIV and TB cases.