A study on drug resistance of newly admitted pulmonary tuberculosis patients with special reference to the resistance to SM, INH, EB and RFP

Abstract

Previously untreated 347 tuberculosis patients newly admitted to our hospital from 1980 to 1991 with positive bacilli and the full record of the drug sensitivity tests were analysed in this study. Among them, 49 cases showed primary resistance to either of major 4 anti-tuberculosis drugs (SM, INH, EB, RFP). The results obtained were as follows: 1. The number of patients with positive bacilli increased with age. The rate of primary drug resistance in patients of age group below 49 were significantly higher than that of age group over 50. 2. The rate of resistance was 8.6% to SM, 4.0% to INH, 1.4% to RFP and 0.6% to EB. These results are consistent with the results of studies of the Tuberculosis Research Committee, Ryoken. EB was frequently substituted to resistant drugs. 3. There was no significant difference between a group with primary resistance and a sensitive group in the various risk and intractable factors, laboratory data as a indicator of risk factors, and in the results of tuberculin skin test. There was also no significant difference in the rate of culture negative conversion of tubercle bacilli and the improvement in radiological findings. 4. We could rarely find the source of infection in 49 cases with primary resistance. In only 5 cases, family contacts were suspected and in another 1 case, the contact in a work place was suspected.