Comparative Diagnosis of Latent Tuberculosis Infection amongst HIV and Diabetic Patients Attending Tertiary Hospitals in Anambra State

Abstract

Aims: The aim of this research work was to survey the epidemiology and diagnosis of Latent Tuberculosis Infection (LTBI) amongst HIV and Diabetic patients in Anambra state of Nigeria using Tuberculin Skin Test (TST) and Interferon Gamma Release Assay (IGRA). Study Design: This was a multicenter study covering three tertiary hospitals in Anambra State involving 480 adult HIV positive and Diabetic patients with 240 normal participants as control. Place and Duration of Study:  This study conducted from February 2016 to April 2018 involved the general hospitals chosen from the three senatorial zones in the state.  Methodology: IGRA using T spot TB as well as TST were done for all the participants. HIV screening, CD4 count and Fasting Blood Sugar were also done accordingly. Results: Overall prevalence of Latent Tuberculosis Infection (LTBI) was 24.4% and 22.5% for IGRA and TST respectively, of the two health groups, HIV group had 35% and 20% for IGRA and TST respectively in their overall prevalence, this was significant (P<.05) compared with the controls which had 2.5% and 4% respectively to IGRA and TST. The diabetics group on the other hand had 13.8% and 25% for IGRA and TST respectively, this also was significant (P<.05) in comparison to its control group with 1.6% each for both IGRA and TST. Out of the 480 patients, 74(15.4%) of them had concordant result, this was 63.2% of the total positive value in the two groups worked on while 43(8.95%) and 34(7%) patients constituted the discordant figures for IGRA and TST respectively.CD4 count was inversely proportional to the presence of LTBI amongst HIV patients using the TST method. Age and duration of illness were significantly associated with LTBI in diabetics (P<.05). Participation rates were higher among males, though females recorded a non significant higher prevalence on the two test methods. Conclusion: There was a high prevalence of latent tuberculosis infection amongst HIV and Diabetic patients in Anambra State. IGRA and TST diagnostic results were not concordant with each other but IGRA appeared to be more specific than TST in diagnosing LTBI.