Latent Tuberculosis Screening and Active Tuberculosis Disease Development in People Living with HIV: A Multicenter Retrospective Cohort Study in Turkiye

Abstract

Background: About 10% of individuals with latent tuberculosis infection (LTBI) develop tuberculosis (TB) disease during their lifetime. People living with HIV (PLWH) have a significantly higher risk of developing tuberculosis disease from latent tuberculosis infection (LTBI) compared to those without HIV. Many HIV treatment guidelines recommend screening and treating for LTBI.

Objective: This study aimed to investigate the LTBI screening frequency of PLWH and the rates of tuberculosis disease development during their follow-up.

Methods: A total of 483 PLWH were admitted to 3 research hospitals between January 2005 and April 2020. Patients who were 18 years and older, who did not have active TB disease, and who were followed up regularly were included in the study. Demographic characteristics and laboratory results of the patients, and tuberculin skin test (TST) and/or interferon gamma releasing assay (IGRA) results were recorded. Whether TB developed during the follow-up of the patients or not was recorded.

Results: A total of 482 PLWH were enrolled in the study, and 429 (89%) of them were male. The mean age of the patients was 37±13 years. The patients were followed for an average of 27.5 months (2-180 months). The mean CD4 count was 381±246/mm3 at the time of diagnosis. A total of 331 patients (68.7%) were screened for latent infection, and 62 (18.7%) of them were diagnosed with LTBI. During the follow-up of the patients, TB disease did not develop in anyone who was not screened for LTBI, while TB disease developed in 4 people who were screened. The mean age of PLWH who developed tuberculosis disease was 54±10 years, while those who did not develop it was 37±13 years, and the difference was statistically significant (p=0.009).

Conclusion: Screening for LTBI in PLWH and treating it when positive are recommended in the EACS guidelines. However, some local HIV guidelines recommend latent TB treatment according to ethnicity, CD4 count, and antiretroviral therapy use. Although the mean follow-up period was short, it was found that there was no difference in the development of TB disease in LTBIpositive and negative individuals in our study. For countries that are not on the list of high-burden countries for TB, it may be an option to give latent TB treatment only to selected patients who have lower CD4 counts.

Keywords: AIDS; HIV; Latent tuberculosis; interferon gamma releasing assay; tuberculin skin test; tuberculous screening..