The bactericidal effect of silver ions on Pseudomonas aeruginosa

Abstract

THERE are frequent reports of Pseudomonas aeruginosa infections in hospitals, with contamination of hospital equipment and pharmaceutical preparations (Editorial, 1967). Cason, Jackson & others (1966) report a high incidence of this organism in burn patients and found silver nitrate compresses to be an effective prophylactic measure. Little information is available on the action of silver ions on Ps. aeruginosa, and the present communication reports the initial stages of such a study. Using cultures whose growth was eventually limited by the magnesium concentration in the culture medium, Brown & Melling (1968) found that Ps. aeruginosa resistance to EDTA was related to the degree of magnesium-limitation. We have examined the effect of magnesium-limitation on sensitivity to silver.