Imaging Diagnosis—sublumbar Pseudomycetoma in a Persian Cat

Abstract

A 6-year-old Persian cat was examined for constipation, anorexia, and vomiting that was subsequently found to be due to a pseudomycetoma originating from the descending colon and sublumbar region, and causing mechanical obstruction of the colon and rectum. Multiple discrete hyperechoic foci likely representing fungal grains within the lesion gave the mass a coarse echotexture on ultrasound and was supportive of the diagnosis and computed tomography allowed delineation the extent of the mass. A pseudomycetoma is a granulomatous/pyogranulomatous reaction that surrounds dermatophytic fungal hyphae. Definitive diagnosis of a dermatophytic pseudomycetoma requires identification of the etiologic agent by cultivation or immunohistochemical staining. A pseudomycetoma should be included in the differential diagnosis for an abdominal mass in a Persian cat, especially is accompanied by the sonographic findings noted above.

Disseminated dermatophytic pseudomycetoma caused by Microsporum species

“…Most of them are caused by Microsporum canis. 12,13 Human cases of pseudomycetomas caused by Microsporum canis have been reported, most commonly in the scalp of young adults and children. [14][15][16] The etiological agents causing pseudomycetomas include Microsporum canis, Microsporum ferrugineum, Microsporum audouinii, Tricophyton rubrum, Tricophyton mentagrophytes, Tricophyton tonsurans, and Tricophyton schoenleinii.…”

Successful treatment of an intra-pelvic fungal pseudomycetoma causing constipation and hypercalcaemia in a Persian cat

“…Dermatophyte penetration into body cavities is extremely rare and, to date, only three cases of intra-abdominal pseudomycetoma in cats have been reported in the veterinary literature. 7,9,10 In the first case the cat died 3 weeks after a therapeutic trial with itraconazole; however, the cause of death was unknown, as post-mortem examination was not allowed. The other cats were euthanased owing to financial constraints or poor prognosis.…”