ABNORMAL CHEST X-RAYS IN INTRAVENOUS-DRUG-USERS - IMPLICATIONS FOR TUBERCULOSIS SCREENING PROGRAMS

Objectives. The purpose of the study was to (1) determine the prevalence of significant abnormalities in routine chest x-rays used to screen for pulmonary tuberculosis in intravenous drug users and (2) evaluate the ability of the purified protein derivative skin test to identify persons with such abnormalities. Methods. We conducted a cross-sectional screening study on 1314 persons admitted to an opiate detoxification unit in an urban jail. Purified protein derivative tuberculin reactivity and the prevalence of abnormalities consistent with tuberculosis on screening chest x-rays were evaluated. The chest x-ray was obtained independent of the skin test. Results. The chest x-rays of 73 of the inmates (5.6%) showed abnormalities consistent with tuberculosis. Tuberculin skin testing missed 17 of 26 chest x-rays (65%) with significant infiltrates. Conclusions. Purified protein derivative screening is insensitive to chest x-ray abnormalities that require additional diagnostic evaluation for tuberculosis. Routine chest studies should be performed on all intravenous drug users admitted to congregate housing settings.