Effectiveness of a combined (4% chlorhexidine digluconate shampoo and solution) protocol in MRS and non-MRS canine superficial pyoderma: a randomized, blinded, antibiotic-controlled study

Background There is a lack of studies comparing topical antiseptics to systemic antibiotics in the treatment of canine superficial pyoderma. Hypothesis/Objectives To compare the efficacy of topical chlorhexidine with systemic amoxicillin–clavulanic acid for the treatment of canine superficial pyoderma. Animals A randomized controlled trial was conducted in dogs with superficial pyoderma. Group T (n = 31) was treated topically with 4% chlorhexidine digluconate shampoo (twice weekly) and solution (once daily) for 4 weeks. Group S (n = 20) was treated orally with amoxicillin–clavulanic acid (25 mg/kg) twice daily for 4 weeks. Methods Bacterial culture and susceptibility testing were performed on clinical specimens collected before treatment. Severity of lesions and number of intracellular bacteria were evaluated using four-point scales to calculate a total pyoderma score for each dog. Pruritus was assessed by owners using a visual analog scale (range 0–10). Scores were analysed for statistical differences between groups T and S. Results Staphylococcus pseudintermedius was isolated from 48 dogs, including eight meticillin-resistant strains (MRSP). Although the number of dogs was small, no significant differences in pyoderma and pruritus scores were observed between groups throughout the study except for day 1, when group S had a significantly higher total score than group T (P = 0.03). Treatment with chlorhexidine products resulted in resolution of clinical signs in all dogs including those infected with MRSP. Conclusion and clinical importance Topical therapy with chlorhexidine digluconate products may be as effective as systemic therapy with amoxicillin–clavulanic acid. This finding supports the current recommendations to use topical antiseptics alone for the management of superficial pyoderma.