Enhanced tuberculosis identification through 1-month follow-up of smear-negative tuberculosis suspects

Bandim Health Project, Bissau, Guinea-Bissau.

To conduct tuberculosis (TB) screening among former TB suspects in whom TB had been ruled out on initial consultation and therefore assumed to be TB-negative (aTBneg).

In a cohort follow-up study, 'aTBneg suspects' were screened for symptoms from 1 month after the initial negative sputum smear examination. Symptomatic individuals were referred for clinical re-examination and human immunodeficiency virus (HIV) testing.

Among 428 TB suspects presenting over a 10-month period in 2007, 80% (343) were smear-negative. Of these, 21 were subsequently diagnosed with smear-negative TB. Of the remaining 322 aTBneg patients, 212 were followed up and symptoms were examined ≥1 month after initial examination. Among followed up patients, 89 (42%) were still symptomatic: five were diagnosed with TB on the basis of repeated sputum smears and chest X-ray. Of 44 symptomatic patients, 39% (n = 17) were HIV-infected. Thirteen (4%) of the 322 aTBneg suspects died before follow-up.

A large proportion of aTBneg patients remained symptomatic after 1 month. Several TB cases had initially not been diagnosed, and HIV infection was highly prevalent. aTBneg suspects have a high mortality rate and need increased attention from both TB and HIV programmes.