Encephalitozoon Cuniculi as a Kidney Parasite in the Rabbit

Abstract

A spontaneous epidemic of nephritis among young rabbits associated with a protozoan parasite has been observed in a certain breeding stock since 1918. It is regarded as a nest infection. The parasite is tentatively classed among the microsporidia and the stages encountered are regarded as vegetative which may perhaps pass through several generations in the same host. It is a parasite of the epithelial cell, provoking no immediate host reactions. These are supposed to follow injury such as destruction of the epithelium and denudation and plugging of the tubules. The localizations in the brain are also without cell reaction, except under special conditions, and the many cell foci present are attributed to coccidia and perhaps bacteria and other intestinal parasites. The kidneys are looked upon as the normal habitat and the brain parasites as aberrant and outside the normal cycle unless it can be shown that the spores discharged into the circulation may again multiply in some organ like the kidneys in direct communication with the exterior. It is highly probable that many reported cases of nephritis among older rabbits used in experiments had their origin in an early invasion of the parasite described.

Comparative evaluation of specific methods for labeling of Encephalitozoon cuniculi in paraffin wax–embedded tissue samples

“…These round structures were considered to be early developmental forms of E. cuniculi . This finding is comparable to a previous report, 16 where similar immature structures are described in light microscopic examinations. However, ISH potentially failed to detect all developmental stages of the organism.…”

Humoral immune response to infection with Encephalitozoon cuniculi in rabbits

“…A high incidence of encephalitozoonosis in domestic rabbits was reported in several surveys (Smith & Florence, 1925;Robinson, 1954;Ostler, 1961;Howell & Edington, 1968;Koller, 1969;Pattison, Clegg & Duncan, 1971;Pakes, Shadduck & Olsen, 1972;Waller, 1977). Since this infection may interfere with results obtained in biomedical research (Shadduck & Pakes, 1971;Cox, 1977), all rabbits used should be free of the disease.…”

The immunoperoxidase test diagnosis of Encephalitozoon cuniculi in rabbits

“…The disease can be observed histologically by the identification of the distinctive lesions in the brain and kidney and, more rarely, by finding spores of the parasite in these tissues by the use of suitable stains (McCartney, 1924;Smith & Florence, 1925).…”