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This study was designed for early detection of drug resistance in Category II failure tuberculosis (TB) patients and to introduce a simple method to detect multi-drug resistant Mycobacterium tuberculosis (M.TB) from direct sputum sample. Total one hundred Ziehl-Neelsen (Z-N) staining positive Category II failure TB patients were enrolled in this study. Culture and drug susceptibility was done by slide and conventional method, among which 90 samples were positive by slide culture and 87 samples were positive by conventional culture. Susceptibility test by slide method showed 85 (94.44%) resistance to one or more anti -TB drugs. Resistance to Isoniazide (INH), Rifampicin (RMP), Ofloxacin (OFX) and Kanamycin (KA) was 94.44%, 84.44%, 31.11% and 4.44% respectively. By this method 80% isolates were detected as Multi-drug resistant (MDR) M.TB and 4.44% isolates were detected as Extended drug resistant (XDR) M.TB. Susceptibility results by slide DST demonstrated good concordance with conventional DST methods. Statistical analysis showed that, Sensitivity of slide DST method was 98.8%. Susceptibility results were available much faster by slide DST method (12.5±0.5 days) compared to that by conventional DST (60.4±5.9 days). Rate of contamination was also much lower by slide DST method than conventional culture (0.18% Vs 3.25%). The present study reflected that the slide DST method could be applied as rapid diagnostic tool to detect drug resistance among Category II failure TB cases, which is essential for applying appropriate therapy.DOI: http://dx.doi.org/10.3329/bjmm.v5i2.16910 Bangladesh J Med Microbiol 2011; 05 (02): 6-10

Mecillinam is one of the very few oral antibacterial agents used against extended spectrum β- lactamase (ESBL) producing Escherichia coli (E. coli) causing urinary tract infection (UTI)). It is reported that, resistance to mecillinam can be reversed to some extent by adding beta lactamase inhibitor like clavulanic acid. The present study was aimed to determine in-vitro activity of mecillinam and mecillinam-clavulanic acid combination on the susceptibility of ESBL producing and non-ESBL producing E. coli . Total 124 E. coli (78 ESBL positive and 46 ESBL negative) isolates from urine samples of patients with UTI were included in the study. Organisms were isolated from patients attending BIRDEM General Hospital from July 2012 to December 2012. ESBL production was tested by double disc synergy test. Minimum inhibitory concentration (MIC) of mecillinam and clavulanic acid against E. coli was determined by agar dilution method. Of the total E. coli isolates, 62.9% was ESBL positive and 37.1% was negative for ESBL. Out of ESBL positive isolates, 75.6% was sensitive to mecillinam while ESBL negative isolates showed the sensitivity as 67.4%. The sensitivity to mecillinam of ESBL positive and negative isolates increased to 85.9% and 86.9% respectively by addition of clavulanic acid with mecillinam. The MIC values of intermediate and resistant isolates converted to sensitive MIC range after addition of clavulanic acid with mecillinam. Conversion of resistance of ESBL producing isolates by adding clavulanic acid was also evident by the reduction of MIC 50 and MIC 90 from 4μg/ml to ≤1 μg/ml and from 128 μg/ ml to 64 μg/ml respectively. Similar trend of reduction of MICs was also observed in non-ESBLs. In conclusion, both ESBL positive and negative E. coli demonstrated considerable sensitivity to mecillinam and the sensitivity increased significantly (p