Detection of Pulmonary Tuberculosis by Gene Xpert Method among HIV Patient in ART Center, Gadarif State, Sudan

Background: Tuberculosis (TB) is one of the most common and deadly infectious diseases in humans. Due to widespread poverty, inequity, and conflict, suboptimal health services in many countries, and the impact of the HIV/AIDS pandemic, TB/HIV co-infected patients frequently test negative for TB with direct microscopy, posing diagnostic challenges. Traditional HIV-associated TB diagnosis is complex, expensive, time-consuming, and technically demanding because it relies on conventional culture and drug susceptibility testing. The lengthy wait for results has disastrous consequences for patients who go undiagnosed or are diagnosed too late.

Objective: To detect the accuracy of gene X pert® MTB/RIF as a novel automated molecular tool to diagnose Mycobacterium tuberculosis in HIV patients.

Methods: A cross sectional study was conducted on 70 HIV patients suspected to have Mycobacterium tuberculosis and who were referred to the ART and Tuberculosis Centers at Gadarif state, from June 2022 to December 2022. Sputum samples were tested by two methods involved the Gene X pert (Cepheid, California, United States of America) and direct smear microscopy (SM) stained with ZN stain for detection of acid fast bacilli. Out of 70 sputum samples analyzed for acid fast bacilli, 50(71%) cases were positive using GeneXpert whereas the DM was positive only for 28 (4o %) of the cases. GeneXpert detected another 22 AFB positive cases. Therefore GeneXpert is more accurate. Sensitivity of the GeneXpert was calculated as 93% and the specificity was 43%. The majority of the patients who contributed to (SM) were found to be co-infected with HIV.

Conclusion: GeneXpert demonstrated two-time case detection rate compared to the sputum smear microscopy so the direct smear showed poor performance tool for evaluation of TB-HIV co-infection. Also The Gene X pert’s sensitivity was found to be high while the specificity was low. Although this was the case, the GeneXpert as compared to DM could greatly reduce false negatives and the wait on treatment initiation can be significantly shortened, minimising premature death and continued transmission.