Enhanced Susceptibility of Diabetic Mice to Gram-Negative Organisms

Abstract

The virulence of gram-negative organisms was studied in experimentally alloxan-induced diabetic mice. There was no significant difference in the mortality rate between normal and diabetic mice when intraperitoneally challenged with any of E. coli, K. pneumoniae, S. marcescens and P. aeruginosa with or without hog gastric mucin. Diabetic mice, however, proved higher susceptibility to urinary tract infection with either of P. mirabilis and S. marcescens and pulmonary infection with K. pneumoniae than nondiabetic controls. The function of polymorphonuclear cells and macrophages from normal and diabetic mice was investigated. Chemotactic activity of both phagocytes and phagocytic activity of macrophages from diabetic mice were lower than those from normal ones. These findings suggest that the increased susceptibility to bacterial infections of diabetic mice can be affected by the bacterial strain and infecting route.