High Yield of Active Tuberculosis Case Finding Among HIV-Infected Patients Using Xpert MTB/RIF Testing

Open Forum Infect Dis. 2019 May 17;6(6):ofz233. doi: 10.1093/ofid/ofz233. eCollection 2019 Jun.

Abstract

Objective: Conduct an active case finding study in Tbilisi, Georgia, for pulmonary tuberculosis (TB) among people living with HIV (PLWH).

Methods: Newly diagnosed HIV patients were assessed for symptoms and asked to submit sputum samples for smear microscopy, culture, and molecular diagnostic testing (Xpert MTB/RIF).

Results: Among 276 PLWH, 131 agreed to participate and 103 submitted sputum samples. Most participants were male (70%) and mean age of 43 years. There were high rates of a positive hepatitis C virus (HCV) antibody test (46%) and the median CD4 count was 122 cells/mm3. A total of 15 (11.5%) persons were diagnosed with pulmonary TB, including 1 each with multidrug-resistant and isoniazid-resistant disease. Twelve had a positive culture for Mycobacterium tuberculosis and Xpert TB/RIF assay, and 4 had positive smear microscopy. Patients with pulmonary TB were more likely to use injection drugs (67% vs 36%, P = .02) and have a positive HCV antibody (73% vs 42%, P = .02). The presence and absence of any TB symptom had a sensitivity and negative predictive value for TB of 93% and 98%, respectively.

Conclusion: Our findings highlight the high prevalence of TB among newly diagnosed HIV-infected patients in an area with high rates of drug-resistant TB and the utility of an active case finding strategy for TB diagnosis.

Keywords: Case finding; Georgia; TB symptoms; Tbilisi.