In scientific literature, there is growing evidence on the resistance of S. pseudintermedius to methicillin [methicillin-resistant S. pseudintermedius (MRSP)] and other antimicrobials of beta-lactamase group, which is related to the mecA (methicillin-resistance) gene (32, 34, 35), which complicate the treatment of insidious infections such as those occurring in dogs suffering from deep pyoderma. The gene discussed is LACTB; the disease is infection.