Resistant strains isolated from bacteremia patients in northern Norway.

Bacterial isolates from blood cultures in 1985 and 1989 (227 and 258 isolates, respectively), were compared as regards resistance to a series of antimicrobial agents including the more recent beta-lactams and quinolones. An increase in the number of coagulase-negative staphylococcal strains and a decrease in Staphylococcus aureus strains were detected, otherwise there were no significant differences in the bacterial patterns in 1985 compared to 1989. Except for chloramphenicol, there was no major increase in antimicrobial resistance among Gram-negative species. An increase in the number of multiresistant enterobacteriaceae strains was due to an increased number of klebsiella strains and a decrease in Proteus mirabilis. S. aureus showed an increased resistance to sulfonamides. No methicillin-resistant strain was found. Coagulase-negative staphylococci were significantly more often multiresistant in 1989 than in 1985, and significant increase in resistance to gentamicin, sulfonamides and fusidic acid was found.