Chin acne is a term used to describe the presence of multiple comedones (blackheads) on the chin, commissures, and perioral area of cats. The skin around the mouth and on the chin of cats is rich in sebaceous glands, which secrete an oily material for scent marking in this species. When the ducts leading from the gland to the skin becomes occluded, oil and bacteria accumulate and a comedone is formed. These comedones are relatively benign unless they are present in large numbers or unless they develop into folliculitis and furunculosis. The sudden development of marked comedones in a cat should alert the clinician to the possibility of an underlying disease. Feline demodicosis, dermatophytosis, and Malassezia infections have been diagnosed in such cats. Skin scrapings, fungal culture, and cytologic preparations of the debris expressed from these comedones should be examined.
Treatment will depend on the underlying cause. Cats with bacterial infections will require 3 to 4 weeks of antibiotic therapy, and the owner should be instructed not to squeeze the comedones because this can cause more inflammation and spread the infection through the dermis. Hot packing the cat's face may be beneficial, if the patient is cooperative.
The development of comedones in older cats has been attributed to diminished grooming activity or cessation of grooming of the face by the cat. The development of comedones in older cats is a common geriatric finding independent of grooming activity, unless the cat is severely arthritic. Careful evaluation of the patient rarely confirms poor grooming behavior in these older cats. In addition, owners rarely report decreased grooming activity preceding the onset of acne. Treatment of these cats depends primarily on how objectionable the condition is to the owners. The comedones tend to wax and wane, causing little discomfort to the cat, unless an infection develops. The area can be washed daily with benzoyl peroxide; however, given the choice, most cats would rather be left alone.
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