Staphylococcal kidney abscesses in rats treated with corticosteroids

Area of Science:

• Veterinary Medicine
• Microbiology
• Immunology

Background:

• Staphylococcus aureus is a common pathogen in animal models.
• Corticosteroids can modulate immune responses and increase susceptibility to infections.
• Rat breeding colonies can harbor endemic bacterial strains.

Purpose of the Study:

• To investigate the development of kidney abscesses in corticosteroid-treated rats.
• To identify the bacterial agents responsible for abscess formation.
• To determine if rat strain influences corticosteroid sensitivity and infection outcome.

Main Methods:

• Infection of two inbred rat strains with Staphylococcus aureus.
• Administration of corticosteroids to the treated rats.
• Isolation and phage typing of S. aureus from kidney abscesses.

Main Results:

• Heavy growth of Staphylococcus aureus was isolated from kidney abscesses in corticosteroid-treated rats.
• The specific S. aureus phage types causing abscesses were found to be endemic in the rat colonies.
• One rat strain exhibited greater sensitivity to the effects of corticosteroid treatment, correlating with abscess development.

Conclusions:

• Corticosteroid administration can predispose rats to Staphylococcus aureus kidney abscesses.
• Endemic S. aureus strains in rat colonies can cause significant infections under immunosuppression.
• Differential sensitivity to corticosteroids exists between rat strains, influencing susceptibility to bacterial infections.