Pyoderma literally means “pus in the skin” and can be caused by infection, inflammation, or cancer. It is not common in cats.
The most common sign of bacterial pyoderma is excessive scaling, particularly on the back near the tail. Scales are often pierced by hairs. Intact pustules are almost never found. Hair loss leads to small bald patches in affected areas or just excessive scaling. Deep pyoderma in a cat is most commonly seen as either a cat bite abscess or chin acne. Recurrent, nonhealing deep pyoderma in cats can be associated with multisystem disease, such as infection with feline immunodeficiency virus or feline leukemia virus, or atypical mycobacteria.
Diagnosis is based on signs. It is also important to identify any underlying causes. The most common causes include fleas, allergies, and poor grooming. However, any disease that causes itching and self-trauma can trigger a pyoderma. Multiple deep skin scrapings are needed to exclude parasitic infections. Bacterial and fungal cultures may also be done.
The most common causes of a bacterial pyoderma that recurs after treatment include failure to identify an underlying trigger or stopping antibiotics too soon. Thus, it is important to fully follow your veterinarian's instructions for any medication. Cats often have concurrent bacterial and yeast infections of the skin, and it is not uncommon for your veterinarian to treat both diseases.
Antibiotic treatment is usually prescribed for at least 3 weeks. Longterm, recurrent, or deep pyodermas typically require 8 to 12 weeks or longer to heal completely.
Attention to grooming is also crucial. The hair coat should be clipped in cats with deep pyoderma and a professional grooming is recommended in medium- to longhaired cats. This will remove excessive hair that can trap debris and bacteria and will help grooming. Carefully follow your veterinarian's instructions regarding grooming.
Last full review/revision July 2011 by Karen A. Moriello, DVM, DACVD; Thomas R. Klei, PhD; David Stiller, MS, PhD; Stephen D. White, DVM, DACVD; Michael W. Dryden, DVM, PhD; Carol S. Foil, DVM, MS, DACVD; Paul Gibbs, BVSc, PhD, FRCVS; John E. Lloyd, BS, PhD; Bernard Mignon, DVM, PhD, DEVPC; Wayne Rosenkrantz, DVM, DACVD; Patricia A. Talcott, MS, DVM, PhD, DABVT; Alice E. Villalobos, DVM, DPNAP; Patricia D. White, DVM, MS, DACVD