Probiotics as an adjunct in the treatment of canine atopic dermatitis: a systematic review and meta-analysis of in vivo studies in dogs

Abstract

Probiotics have been suggested as a treatment for canine atopic dermatitis, a form of dermatopathy common in dogs. This systematic review and meta-analysis aimed to evaluate the effect of probiotics as an adjuvant in treating canine atopic dermatitis in vivo studies with dogs. The study was conducted following the PRISMA guidelines. Only clinical studies in dogs with atopic dermatitis that received intervention with probiotics were selected, being just original articles in English from the last 5 years (2019–2023). A total of 293 articles were obtained, and after the inclusion criteria, only 5 articles were eligible and included in the systematic review and meta-analysis. The 5 studies used different probiotics at concentrations of 10⁸ to 10¹⁰CFU/mL/g, 3 studies with oral administration for 12 weeks, and 2 studies with topical use for 4 weeks. The meta-analysis results show that probiotics did not present significant effects against atopic dermatitis by evaluating the CADESI-4 scale (P=0.08) and the PVAS scale (P=0.85). Furthermore, regarding the method of administration of probiotics (oral or topical), the meta-analysis showed that there were also no significant results when the disease index was evaluated using CADESI-4 (P=0.07) or PVAS (P=0.92). We concluded that, even without significant effects, all trials showed a reduction in CADESI-4 and PVAS scores, reflecting a reduction in the severity of atopic dermatitis in dogs that used probiotics as treatment adjuvants.