Comparison of symptoms and treatment outcomes between actively and passively detected tuberculosis cases: the additional value of active case finding

Passive detection of tuberculosis (TB) cases may lead to delay in treatment which may contribute to increased severity of disease and mortality. Active case finding may be an alternative. In a community survey in Cape Town, South Africa, we actively detected 27 bacteriologically positive TB cases and compared those with 473 passively detected TB cases. Seven of 27 (26%) actively detected TB cases did not start treatment within 2 months and were considered initial defaulters. Those who did start treatment had similar treatment success rates as passively detected TB cases (both 80%) (OR 1.01, CI 0.33-3.09). Passively detected cases reported the presence of the symptoms cough (OR 3.72, 95% CI 1.47-9.39), haemoptysis (OR 3.20, 95% CI 1.03-9.93), night sweats (OR 3.35, 95% CI 1.40-7.99), fever (OR 4.28, 95% CI 1.21-15.14), and weight loss (OR 11.14, 95% CI 4.17-29.74) more often than those detected actively. We conclude that although TB cases detected by a community survey are less symptomatic and are prone to a high initial default rate, active case finding can potentially identify a substantial portion of the existing caseload at an earlier stage of disease, thereby reducing the risk of transmission.