Susceptibility of gram-negative bacteria isolated from a paediatric hospital environment to antibiotics.

The majority of tested Gram-negative strains isolated from the hospital environment were resistant to 6-14 used antibiotics. The greatest resistance was shown by three strains: Enterobacter cloacae, Proteus mirabilis and Ps. maltophilia, which were resistant to all tested drugs. The most effective antibiotic was gentamicin, at least against half of bacteria belonging to Enterobacteriaceae family, to 90% of strains from Pseudomonas genus and to all other Gram-negative rods. Cephtazidim, cephotaxim, colistin and carbenicillin were effective only to 60-70% of Enterobacteriaceae family strains, whereas ampicillin and tetracycline to 70% of Pseudomonas genus. Other Gram-negative bacilli were more susceptible to antibiotics. Cephalothin was ineffective to all tested strains.