Drug Sensitivity of Bacteria Isolated by Blood Culture

Abstract

564 consecutive positive blood cultures were analysed. The sensitivity for 16 antibiotics was tested and the number of strains found to be simultaneously resistant to two antibiotics was counted for all combinations. Bacteremia was more common in the higher age groups and mostly caused by gram-negative enteric bacteria. In the younger age groups bacteremia was mainly caused by Staphylococcus aureus and other bacteria characteristic of the skin and airways. Gentamicin was the single most effective antibiotic in vitro against most bacterial strains, but it proved inadequate against the common streptococci and pneumococci and might therefore be combined with a penicillin. Such a combination was theoretically effective against 99% of all strains. Chloramphenicol was the second broad spectrum antibiotic.