Klebsiella pneumoniae clinical isolates: susceptibility to some antibiotics and surface hydrophobicity.

The susceptibility of Klebsiella pneumoniae strains isolated from the respiratory tract (55), urinary tract (19) and other human body sites (8) to the antibiotics, amoxycillin/clavulanate, cefuroxime, ceftazidime, gentamicin, norfloxacin, colistine, cotrimoxazole and oxolinic acid, as well as their surface hydrophobicity, were studied. The strains expressed a very high sensitivity to the antibiotics (94.7-100%). The surface hydrophobicity of the strains was evaluated by means of three assays and was minimal. The hydrophobicity manifested by adherence to xylene ranged between 0 and 10% for 96.4% of the respiratory strains, and for 100% of the urinary and other sites. Weak binding of Congo red (10-29 micrograms/10(10) cells) showed 96.4% of respiratory isolates as well as 100% of the urinary and other strains. Results of the salt aggregation test showed that 96.4% of respiratory strains and 100% of urinary and other strains aggregated only at 1.5 M, 2 M or higher concentrations.