Changing patterns of susceptibilities of blood, urinary and respiratory pathogens in Hong Kong

The incidence and antimicrobial susceptibility of organisms isolated from blood, urine and respiratory specimens at a teaching hospital in Hong Kong were studied retrospectively from 1986-1993. The incidence of Gram-positive bacteraemia, particularly coagulase-negative staphylococci (CNS), increased significantly from 33·6 to 47·3% (P < 0.001) while that of Gram-negative bacteraemia fell from 60·0 to 47·0% (P < 0.001). Among blood isolates, methicillin resistance of CNS increased from 17·0 to 58·0% (P < 0.001) and cefuroxime resistance of Enterobacter spp. increased from 21·0 to over 50% (P < 0.001). Among urinary isolates, cefuroxime resistance of Klebsiella spp. (11·0 to 24·0%, P < 0.001) and Enterobacter spp. (32·0 to 75·0%, P < 0.001) increased. Nalidixic acid resistance among Gram-negative urinary isolates, except Proteus mirabilis, rose by three- to sixfold. For Streptococcus pneumoniae, isolated from the respiratory tract, penicillin resistance increased dramatically (2 to 18%, P < 0.001). For respiratory isolates of Haemophilus influenzae, ampicillin resistance increased from 17·0 to 29·0% (P < 0.001). These data are useful in guiding empirical treatment of nosocomial infections.