Experimental systemic cryptococcosis in SCID mice.

The susceptibility of severe combined immune deficiency (SCID) mice to experimental systemic cryptococcosis was studied. SCID mice were at least 16-fold more susceptible to lethal infection than were immunocompetent control mice (P < 0.001). Histological assessment showed that control mice responded with a granulomatous inflammatory response, whereas SCID mice showed no evidence of a cellular host response. In a therapeutic study, 5 mg kg-1 day-1 of fluconazole caused a significant reduction in the infectious burden in the spleen, liver, kidney and lungs of treated mice compared with no treatment. These results indicate that a model of systemic cryptococcosis with meningitis in SCID mice may have utility in the study of immunology and therapy of this disease in the severely immunocompromised host.