Screening for tuberculosis among household contacts of index patients

ABSTRACT

Household contacts of sputum positive pulmonary TB cases are at a high risk of getting infected with tuberculosis therefore symptomatic or vulnerable individuals should be screened and treated early. To determine the prevalence of pulmonary tuberculosis in the households contacts of index patients having pulmonary tuberculosis infection using standard diagnostic tests and refer the positive cases to DOTS program for treatment. This national descriptive study was conducted in seven Centers of PMRC throughout Pakistan form November 2010 to March 2012. A total of 580 index adult patients suffering from pulmonary tuberculosis, being treated at DOTs Centers of major tertiary care hospitals of Karachi, Lahore, Multan, Peshawar and Quetta living within 5-8 kilometers of the hospital, who consented to participate in the study were selected from the DOTs centres. Generally one but occasionally two close contacts of these index patients [spouses, parents or siblings] were called to the hospital for screening of TB using chest Xray, smear microscopy and tuberculin skin test. Out of 800 contacts screened, 125 [15.6%] were positive on sputum smear examination while 113 had infiltration on X-rays along with positive tuberculin skin test [Indurations of >10 mm] making a definitive diagnosis of TB. Calcified lesions were seen on X-rays in another 91 cases giving evidence of past infection, however 26 of these were AFB positive indicating either the relapse of disease or active lesion. Low grade fever and weight loss were the most significant findings in contacts that were positive on sputum smear and radiology. Almost 15.6% household contacts of pulmonary tuberculosis patients have pulmonary tuberculosis. Health care providers in general and DOTs staff in particular should be trained to inform all index cases that their close contacts especially those suffering from weight loss and fever should be screened for tuberculosis and treated if required