Sarcoptic mange and iatrogenic hyperadrenocorticoidism in a dog undergoing hyposensitisation for atopy based on RAST testing.

摘要

A 3.5-year-old Labrador Retriever was presented with a two-year history of non-seasonal, severe pruritus, which was not responsive to corticosteroids. Immunotherapy based on a positive in vitro RAST (radioallergo sorbent testing) for aeroallergens was used unsuccessfully for 18 months. At presentation, the dog showed typical signs of hyperadrenocorticism. Adrenocorticotrophic hormone stimulation testing demonstrated that this was iatrogenic in nature. Sarcoptic mange (Sarcoptes scabiei) was diagnosed on skin scrapings. Response to ivermectin therapy and corticosteroid withdrawal was dramatic. There was no relapse of the disease during a 10-month follow-up period. It is suggested that sarcoptic mange was the primary disease rather than secondary tocorticosteroid therapy, although longer follow-up would be needed to rule out a seasonal allergen. The use of serological testing for the diagnosis of atopy is discussed.