Active Case Finding for Tuberculosis among Prisoners in Karachi, Pakistan

Objective: Pakistan is ranked fifth among high Tuberculosis (TB)-burden countries. Globally, up to 25% of all TB burden may be accounted for TB cases in prisons. Unfavorable conditions of prison and stress coupled with inadequate medical access contributes to a higher risk of developing and spreading TB with poor treatment outcomes. The aim of this study was to estimate the yield of TB among the inmates screened through an active case finding approach in a prison of Karachi, Pakistan. Methods: Between September 2017 to December 2018, 57 mobile X-ray screening camps were conducted in “District Prison Malir, Karachi”. All prisoners were screened through computer aided detection for TB (CAD4TB) on chest X-rays. A CAD4TB cut-off of 70 was used to detect abnormal X-rays. Sputum was collected for Xpert testing from TB presumptive prisoners and a medical officer evaluated for clinical TB. Results: A total of 6,527 prisoners were screened for TB, of which 470 had abnormal x-ray. Xpert tests were run on 374 sputum samples, 17 were MTB positive and 100 prisoners were clinically diagnosed and registered for anti-tuberculous therapy. The TB yield was 1.8% out of screened prisoners and 24.9% out of all presumptives. (Table 1.) Conclusion: Active screening results in substantially high TB yield among prisoners. Screening for TB and ensuring treatment success among TB patients in the prisons in a high TB burden country is integral to TB control in the country.