Comparison of the Bactec system and Lowenstein-Jensen medium for the isolation of Mycobacterium tuberculosis and determination of drug sensitivity with Bactec

A total of 2058 different specimens (sputum, cerebrospinal fluid, pleural fluid, gastric aspirate, urine, bronchial lavage, lung aspirate) sent to the central laboratory from clinics and but-clinics of Balcali Hospital of Cukurova University, Faculty of Medicine, Adana, were evaluated for Mycobacterium tuberculosis using Bactec system and Lowenstein-Jensen (L.J.) media. Out of a total of 112 cultures positive for M. tuberculosis, 100 (89.28%) were positive in the Bactec system and 76 (67.85%) with L.J. media. The average day on which the culture was found to be positive was 11.59 for the Bactec system and 22.41 with L.J. medium. The rate of sensitivity to drugs was as follows; Ethambutol (EMB) 97.32%, Rifampin (RFP) 87.5%, Streptomycin (SM) 85.71% and Izoniazid (INAH) 83.09%. The rate of primary contamination was 120 (5.89%) with the Bactec system and 94 (4.56%) with L.J. medium. However using the decontamination method of the Bactec system, the results of 72 cultures were evaluated whereas it was impossible to decontaminate the L.J. cultures. Thus, the final rate of contamination with the Bactec system was found to be 2.33 percent