RESISTANCE OF GRAM-NEGATIVE BACILLI AND THEIR SENSITIVITY TO COMBINATION OF ANTIMICROBIAL AGENTS IN VITRO

Abstract

Members of Family Enterobacteriaceae have been associated with clinical syndromes in which bactericidal antibiotics are felt to be impor­ tant. These conditions include sepsis in neutropenic cancer patients and neonatal and nosocomial meningitis. Some Gram-negative bacilli were noticed to acquire resistance to most of the commonly employed antimi­ crobial agents.

Therefore, 61 strains of Gram-negative bacilli were isolated from

115 samples collected from patients suffering from urinary tract infec­

tions, otitis media and wound sepsis.

The isolates after complete identification were subjected to in vitro sensitivity test against 8 ofB-lactams and aminoglycosides, viz, pipera­ cillin, flucloxacillin, cefamandole, cefoperazone, cefotaxime, arri.ikacin, gentamicin and tobramycin.

The strains were found to vary quantitatively in their susceptibility to the individual drugs. Amikan was the most active one against isolates of E.coli, Klebsiella species, Proteus vulgaris and Pseudomonas species. The majority of the E.coli strains was sensitive to 4 of the drugs as such, 80.5% were sensitive to each of cefoperazone and cefotaxime, 76.9% to piperacillin and 73.1% to cefamandole. As regards Klebsiella species, 75% of the tested strains were sensitive to cefotaxime and 67.8% to

piperacillin.