The Methicillin-Resistant S pseudintermedius Crisis: Are We Out of Options to Treat the Most Common Canine Pathogen?

S pseudintermedius is a leading cause of canine pyoderma and an important pathogen in small animal skin, soft tissue, otic, wound, and postoperative infections. The emergence of methicillin-resistant S pseudintermedius (MRSP) has made recurrent infections more difficult to manage by combining multidrug resistance, biofilm-associated persistence, treatment failure, and repeated antimicrobial exposure. This article reviews MRSP emergence and epidemiology, mechanisms of resistance and recurrence, and the limitations of current treatment options. It discusses emerging therapeutic strategies, including phage-based therapies, microbiome-directed interventions, immune modulation, nanomaterials, photodynamic therapy, and antimicrobial peptides, that serve as adjuncts to standard care and reduce reliance on systemic antimicrobials.