Department of Microobiology,Kerman University of Medical Sciences and Health Services, KERMAN,IRAN
Department of Microbiology,School of Public Health,Tehran University of Medical Sciences and Health Services, TEHRAN-IRAN
Department of Microbiology, NRITLD,Shaheed Beheshti University of Medical Sciences and Health Services, TEHRAN-IRAN
Department of Pediatrics, NRITLD,Shaheed Beheshti University of Medical Sciences and Health Services, TEHRAN-IRAN
Background :Reemergence of tuberculosis along with multi drug- resistant strains has made both the treatment of affected patients and the progress of eradication programs a real struggle. Most second –line drugs are toxic and expensive and it is necessary to search for effective anti-tuberculosis drugs which are safer and less expensive. Due to their structure and production of β-Lactamase enzyme, mycobacteria are considered as β -lactam resistant.
Materials and Methods: we study the effects of β -Lactamase inhibition on the susceptibility of mycobacterium to β -Lactamase, changes in Minimal Inhibitory Concentration (MIC) of four cephalosporins; cephapirin, ceftriaxone, cefotaxime, and cefoperazone in the presence of sulbactam in both sensitive and resistant mycobacteria.
Results:β –Lactamase production was assessed with the Nitrosfin method and all strains were β-Lactamase. Resistant strains showed less sensitivity to β -Lactamas and both groups were most sensitive to cephapirin. Equal doses of sulbactam added to the cephalosporins reduced their MICs from zero to 16 times. MIC reduction was more pronounced with ceftriaxone in the sensitive group and with cefoperazone in the resisitant group.
Conclusion:Althoughantimycobacterial effects of β -lactamase such as cephalosporin in combination with β -Lactamase inhibitors, could not be compared with first- line anti TB drugs. We are still hopeful these drugs with the least side effects could be considered as the second- line anti TB drugs in near future.(Tanaffos 2002;1(1):28-35)