Active case finding of undetected tuberculosis among chronic coughers in a slum setting in Kampala, Uganda

Kisenyi slum in peri-urban Kampala, Uganda.

Using chronic cough (> or = 2 weeks) inquiry as a screening tool to identify undetected smear-positive tuberculosis (TB) cases and to describe the characteristics of smear-positive TB cases detected by active case finding.

A house-to-house survey was conducted in five randomly selected villages in Kampala between June and August 2005. A sample of households was visited; adults aged > or = 15 years were consecutively interviewed to identify those with chronic cough. Three sputum specimens were collected and examined by smear microscopy.

Among 930 individuals, we identified 189 (20%) chronic coughers. Of these, we found 33 (18%) undiagnosed smear-positive cases. The newly detected cases had an even sex distribution (P = 0.47), a median age of 30 years, a median cough duration of 1 month and 55% had acid-fast bacilli 1+ sputum smear grade.

These findings suggest that active case finding could supplement DOTS to yield additional smear-positive TB cases, lead to early diagnosis and thus shorten the duration of infectiousness before effective chemotherapy is initiated. In communities such as Kisenyi, this is a feasible strategy that may prove useful for TB control, but its cost-effectiveness needs to be evaluated. Early health care seeking for cough should be emphasized.