Abacillary pulmonary tuberculosis

In Copenhagen, a city with a low incidence of tuberculosis, 72 patients with discrete pulmonary infiltrates on the chest X-ray had a tentative diagnosis of tuberculosis. All were sputum smear negative for acid-fast bacilli. A prospective randomised study was carried out to determine whether these patients would benefit from chemotherapy. Out of the 72 patients, 22 (30.6%) had positive cultures initially and were treated. Of the remaining 50 patients, 22 received chemotherapy and 28 were untreated controls. Among the untreated patients 8 (29%) later became culture positive for M. tuberculosis, whereas none of the treated patients developed culture positive tuberculosis during the follow-up period of 5 years.