Spirocerca lupi (Rudolphi, 1809) Railliet and Henry, 1911
Spirocercalupi is basically a parasite of dogs and other canids, although lesions or signs of lesions have been reported in non-domestic felids (Kikuchi et al., 1976; Murray, 1968; Pence and Stone, 1978). Infections in the domestic cat have been rare to nonexistent. Experimentally, it has been possible to cause lesions in cats although they have not been described under other circumstances.
Faust (1928) described the life cycle of Spirocercalupi, showing that it was capable of utilizing beetle intermediate hosts and various vertebrate paratenic hosts. The life cycle of Spirocercalupi as it relates to the canine host has been described in detail by Bailey (1963—3or 5?????). Bailey exposed adult dung beetles of the genus Geotrupes to large numbers of eggs of Spirocercalupi. In these intermediate hosts, development to the third larval stage occurred. These larvae were found within cysts in the body of the beetle. Some of the cysts contained two or more larvae, while one contained 25 larvae. The cysts possessed a brown sclerotized wall that conformed to the shape of the coiled larva. When ingested by a variety of transport hosts, the larvae either continued a migration similar to that in the definitive host or localized in the wall of some portion of the digestive tract. When the infective third larval stages from either the intermediate or transport host were ingested by the canine host, the larvae excysted in the stomach and began a meandering migration. The larvae continued their migration in the wall of the gastric artery and aorta to the area between the aortic arch and diaphragm. In the canine definitive host, most of the developing larvae traveled through the wall of the aorta and invaded the wall of the esophagus where they induced the formation of a reactive granuloma. This granuloma may vary greatly in size and shape depending on the number of worms present and the pressure of the surrounding tissues. Cavernous tracts often formed around the adult worms; through these apertures, ova passed to the lumen of the esophagus and hence to the external environment via the gut. This parasite does demonstrate a wanderlust activity; it has been reported in many unusual locations, including the kidney, wall of the urinary bladder, subcutaneous abscess, interdigital cyst, trachea, mediastinum, and lung.
Chhabra and Singh (1972) reported on the experimental infection of cats with Spirocerca lupi. Two adult cats given larvae did not develop any signs of infection or lesions. Three kittens that were given 50 to 100 larvae all died within 40 days of the infection. In all three kittens, the lesions that were observed were in the aorta. These authors reported that the majority of larvae were juveniles and that most of the larvae detected were degenerating. Faust (1928) reported that cats served as a model for tracing the routes of migration during early infection, and that the primary lesions in the aortic wall of the cat are much less intense than they are in the dog. Faust felt that in the cat the infections were usually aborted before the worms reached maturity.
Achtar (1939) reported on a cat....[NEEDS TO BE FILLED IN}
The one reported case of Spirocerca in a domestic cat was a single, mature, infertile female, therefore no eggs were observed (Mense et al., 1992). This worm was in the stomach wall of a 7-year-old spayed domestic shorthair cat living in Florida. The cat had chronic postprandial vomiting that persisted for several weeks. On examination, no eggs were detected in the feces, and the cat began a course of antibiotics. Three weeks later, the cat returned to the hospital, radiographs appeared normal, and the cat was started on an oral pertroleum-based laxative. Two weeks later, the cat was still vomiting and a laparotomy was performed which revealed a 1.5 to 2.0 cm nodule in the wall of the pylorus. The nodule was removed and submitted for histological examination. The larva in section was considered to be a larva of Spirocerca based on the morphology of the observed sections through the worm. The sections were compared with those of Gnathostoma and Physaloptera, but comparisons were not made with Cylicospirurafelineus. It would be of interest to determine if this cat was perhaps infected with the later species which is present in the United States in bobcats.
Akhtar SA. 1939. On some nematode parasites from Afghanistan. Proc Ind Acad Sci B 10:287-297.
Bailey WS. 1965. Parasites and cancer: sarcoma associated with Spirocercalupi. Ann NY Acad Sci 108:890-923.
Chhabra RC, Singh KS. 1972. On Spirocercilupi infection in some paratenic hosts infected experimentally. Ind J Anim Sci 42:297-304.
Faust EC. 1928. The life cycle of Spirocercasanguinolenta - a natural nematode parasite of the dog. Science 68:407-409.
Kikuchi S, Ori M, Saito K, Hayashi S. 1976. Scanning electron microscopy of Spirocercalupi obtained from the lower esophagus and cardiac opening of a marbled cat. Jap J Parasitol 25 (Suppl 1): 13.
Mense MG, Gardiner CH, Moeller RB, Partridge HL, Wilson S. 1992. Chronic emesis caused by a nematode-induced gastric nodule in a cat. JAVMA 201:597-598.
Murray M. 1968. Incidence and pathology of Spirocercalupi in Kenya. J Comp Path 78:401-405.
Pence DB, Stone JE. 1978. Visceral lesions in wild carnivores naturally infected with Spirocercalupi. Vet Pathol 15:322-331.