THE ABILITY OF A PROTEUS-MIRABILIS STRAIN TO INVADE THE BLOOD-STREAM IS INDEPENDENT OF ITS PROTICINE PRODUCTION PROTICINE SENSITIVITY TYPE

Proteus mirabilis strains frequently infect the upper urinary tract an d some progress to invade the bloodstream. In an attempt to determine if these were features only of particular strains of P. mirabilis, iso lates from the brood of 38 unrelated patients, many of whom had an und erlying urinary tract infection, and eight from different sources and sites within the upper urinary tract, were analysed by proticine produ ction/proticine sensitivity (p/s) typing. Twenty-six different p/s typ es were found among the 38 isolates from blood and seven among the eig ht isolates from the upper urinary tract. The p/s types found previous ly to be associated frequently with virulence for the upper urinary tr act were not found. Analyses of the frequency of occurrence of the dif ferent p/s types and of their distribution showed no evidence that the p/s characteristics of a P. mirabilis strain conferred any advantage on its ability to infect the upper urinary tract or invade the bloodst ream.