Rush allergen specific immunotherapy protocol in feline atopic dermatitis: a pilot study of four cats

Abstract

Rush immunotherapy has been shown to be as safe as conventional immunotherapy in canine atopic patients. Rush immunotherapy has not been reported in the feline atopic patient. The purpose of this pilot study was to determine a safe protocol for rush immunotherapy in feline atopic patients. Four atopic cats diagnosed by history, physical examination and exclusion of appropriate differential diagnoses were included in the study. Allergens were identified via liquid phase immunoenzymatic testing (VARL: Veterinary Allergy Reference Labs, Pasadena, CA). Cats were premedicated with 1.5 mg triamcinolone orally 24 and 2 h prior to first injection and 10 mg hydroxyzine PO 24, 12 and 2 h prior to first injection. An intravenous catheter was placed prior to first injection. Allergen extracts (Greer Laboratories, Lenoir, North Carolina) were all administered subcutaneously at increasing protein nitrogen units (pnu) every 30 minutes for 5 h to maintenance dose of 15,000 pnus ml-1. Vital signs were assessed every 15 minutes. Two cats developed mild pruritus and the subsequent injection was delayed 30 minutes. No changes in either cat's vital signs were noted, nor was there any further pruritus. All four cats successfully completed rush immunotherapy. Two cats developed a dermal swelling on the dorsal neck one week later. In these four cats, this protocol appeared to be a safe regimen to reach maintenance therapy. A larger sample of feline patients is needed to determine the incidence of adverse reactions and to follow the success of ASIT based upon this method of induction.

Safety of Accelerated Schedules of Subcutaneous Allergen Immunotherapy with House Dust Mite Extract in Patients with Atopic Dermatitis

“…Application of ASAI in the treatment of patients with respiratory allergic diseases has been suggested to increase compliance by reducing time and cost for hospital visits and providing a rapid onset of clinical efficacy (3). Interestingly, rush immunotherapy has been successfully tried in dogs and cats with AD without severe systemic reactions (25, 26). Further studies on the long-term safety and clinical efficacy are needed to evaluate a clinical usefulness of ASAI in patients with AD.…”

A review of allergen‐specific immunotherapy in human and veterinary medicine

“…In a pilot study with four cats, a RIT protocol was conducted to reach maintenance therapy 238 . All allergen extracts were administered subcutaneously in the dorsal neck area at increasing PNUs every 30 min for five hours to an average maintenance of 7500 PNU mL −1 The purpose of this study was to determine a safe protocol for RIT in atopic cats; therefore, clinical efficacy was not assessed.…”

“…Because RIT is associated with a relatively high incidence of systemic reactions in humans, patients are routinely pre‐medicated with a myriad of medications including glucocorticoids, antihistamines and leucotriene inhibitors 246 . With the exception of leucotriene inhibitors similar medications have been utilized in canine and feline pre‐medication protocols 238,239 …”

Allergen‐Specific Immunotherapy

“…Abby Foust emphasized that there are few articles in the veterinary literature on rush immunotherapy, with the exception of Ralf Mueller and Sonya Bettenay's article in the American Journal of Veterinary Research 2001 that described approximately 30 patients, 1 and the report of several cats by Trimmer et al in an article in Veterinary Dermatology in 2005. 2 There appears to be more information regarding rush immunotherapy for desensitization of feline asthma patients.…”