Investigation of tuberculosis contacts in a nonhospital pneumology practice

The aim of this study was to analyze the results of the tuberculosis contac t tracing carried out in an outpatient pneumology setting and to assess its performance with regard to the detection of new cases of tuberculosis and infected contacts. One thousand two hundred and twenty-eight contacts of 30 2 tuberculosis patients were evaluated in the Tuberculosis Unit of the Dr. Fleming Specialities Center between 1992 and 1996. Contacts were categorize d into groups with regard to bacteriological status of the index case (Grou p A, smear-positive; Group B, culture-positive only; Group C, smear- and cu lture-negative) and intimacy of exposure to the index case (close or casual ). The possible association between the existence of infection or disease a nd the bacteriological status of the index case and degree of intimacy of e xposure was analyzed. There were 582 infected contacts (47.4%) and 42 new c ases of tuberculosis (3.4%), six of which were smear-positive. The proporti on of infected and diseased contacts was significantly higher for those who had contact with smear-positive patients and those who had close contact w ith the index case. Chemoprophylaxis was completed in 431 (35.1%) of the co ntacts evaluated, Systematic investigation of contacts represents an effici ent means of discovering new cases of tuberculosis and infection, especiall y among contacts of smear-positive index cases and among those who are clos er to the index case. The administration of appropriate treatment to these contacts will contribute to controlling the transmission of tuberculosis wi thin the community.