Susceptibility to experimental Candida albicans urinary tract infection in the rat

The urinary tract is resistant to ascending infection due to Candida albicans. Host and microbial factors that may alter such resistance were evaluated in the rat after inoculating C. albicans into the urinary tract. Diuresis, diabetes, candidal germ-tube formation, and vaginal Candida colonization (alone or in concert) failed to promote ascending urinary tract infection with two vaginal isolates of C. albicans capable of producing renal infection by the hematogenous route. Both germinated and ungerminated Candida adhered poorly to bladder mucosa. Unlike prior urinary tract infection due to an enterococcus that failed to agglutinate Candida in vitro, prior urinary tract infection with a mannose-binding strain of Escherichia coli that agglutinated C. albicans in vitro enhanced adherence of C. albicans to bladder mucosa and increased susceptibility to ascending C. albicans urinary tract infection. Thus, resistance to Candida ascending urinary tract infection is likely to be due to poor adherence of C. albicans to normal bladder mucosa.