EXPERIMENTAL-STUDY OF ASCENDING CANDIDA-ALBICANS PYELONEPHRITIS FOCUSING ON THE HYPHAL FORM AND OXIDANT INJURY

To investigate the pathogenicity of the hyphal form of Candida in pyel onephritis a Candida albicans strain, assuming only the yeast form but not the hyphal form when induced by ultraviolet mutagenesis, and a re vertant strain from this mutant strain showing bimorphism were compare d in a rat experimental model with regard to the incidence of ascendin g Candida pyelonephritis and the grade of inflammation. To increase th e frequency of pyelonephritis unilateral incomplete ureteral stenosis was created. The revertant strain assuming the hyphal form showed a si gnificantly (p < 0.01) higher frequency of pyelonephritis as compared with the mutant strain not assuming this form, and the grade of inflam mation was also higher in the revertant strain group. Also, higher ren al tissue and serum levels of both lipid peroxide and superoxide dismu tase, which an related to marked renal oxidant injury, tended to be co rrelated with the degree of neutrophil infiltration in the acute phase . These findings suggest that the hyphal form plays an important role in the development of C. albicans pyelonephritis and also that the oxy gen radicals from neutrophils appearing at the sites of inflammation p lay a major part in the further extension of inflammatory lesions.