Gut colonization of mice by yeast: effects of methylprednisolone and antibiotics.

BACKGROUND/AIMS: This study evaluated the effects of broad spectrum antibiotics and methylprednisolone on the gut colonization of mice by C. albicans.

METHODOLOGY

Male Crl:CD1 (ICR) BR mice, 3 months of age, were fed chow containing Candida albicans, while similar mice were fed regular chow. The gut of the Candida-fed mice was colonized by yeast. Groups of mice were subsequently treated for 10 days, with either ceftriaxone, ticarcillin-clavulanic acid, or methylprednisolone, each alone or with the combination of methylprednisolone and each antibiotic. Other Candida-colonized mice received normal saline, and non-colonized mice, serving as controls, received the same drugs and drug combinations or saline.

RESULTS

Candida-colonized mice treated with each antibiotic alone had significantly higher yeast counts in their stool, while those treated with methylprednisolone alone did not. Colonized mice treated with the combination of each antibiotic with methylprednisolone had similar stool concentrations of Candida as mice treated with each antibiotic alone. Saline did not change Candida in the stool concentration. Yeast was not found in the stool of non-colonized mice treated with the drugs under investigation or saline. Dissemination of Candida did not occur in any mouse.

CONCLUSIONS

Ceftriaxone and ticarcillin-clavulanic acid significantly increase gut colonization of mice by yeast, while methylprednisolone, either alone or in combination with these antibiotics, does not.