Review of 15 cases of pemphigus foliaceus in horses and a survey of the literature.

The records of 15 horses with pemphigus foliaceus diagnosed on the basis of their history, clinical signs, histopathology and the exclusion of differential diagnoses were evaluated with respect to the age of onset, the clinical signs and the diagnostic tests used. There was no apparent breed predisposition. The horses' mean age was nine years, with a range from three months to 25.5 years, three were foals up to six months old and eight were nine years old or older. The most frequent lesions were scaling in 11, crusting in 10 and alopecia in 10, and they appeared most commonly on the face, neck and trunk, in 10 horses for each of these sites. The extremities were involved in nine of the horses, pruritus occurred in seven, and four of the horses had pustules. The clinical signs mostly corresponded with those described in previous reports, but signs of pain were not a prominent feature. Acantholytic cells were identified cytologically in four of six of the horses.