Atopy in Cats – From the Cat’s Point of View
Atopy, also known as inhalant allergies or atopic dermatitis, is an immune-mediated, itchy and inflammatory disorder that affects the skin of some cats. It also can affect their respiratory system, causing breathing difficulties (also known as dyspnea). The symptoms of atopy normally show up between 3 months and 3 years of age and tend to worsen as the cat grows older. In cats that live in North America, atopy often waxes and wanes, getting worse during the spring and summer months. In chronic cases, atopy can become non-seasonal, progressing to where the cat has symptoms all of the time. Cats with atopy almost always have intensely itchy, inflamed skin, which in medical circles is referred to as “pruritis.” Atopy is diagnosed less commonly in companion cats than in dogs, and the characteristic signs differ somewhat between those species.
Atopy in Cats – What Owners May See
Owners of cats with atopic dermatitis may notice one or more of the following signs that alert them to their cat’s condition. Unfortunately, these symptoms can mimic those of several other disorders that cause cats to have itchy, inflamed skin:
- Intense and chronic itchy skin is the hallmark of feline atopy; affected cats will scratch, lick, bite and chew at their skin, without getting any apparent relief from their efforts
- Hair loss (alopecia); often symmetrical; can come and go and be seasonal or non-seasonal; tends to affect the feet, face, ears, tail base and underbelly most commonly
- Skin redness, inflammation and irritation
- Skin abrasions, weeping wounds, sores and scabs from self-trauma; can lead to secondary bacterial or yeast skin infections, although this is less common in cats than in dogs
- Breathing and other respiratory difficulties (dyspnea); can mimic the symptoms of feline asthma
- Smelly ear infections (malodorous otitis); swollen inflamed ears with profuse amounts of ear wax; more frequent in atopic cats than in dogs with atopy; can be recurrent or chronic
- Miliary dermatitis or one of several eosinophilic granuloma complex lesions (these are eosinophilic plaques, eosinophilic granulomas and indolent ulcers, the description of which is beyond the scope of this article)
Cats at Increased Risk
There is no reported gender or breed predisposition for atopy in cats. Most symptoms of the disorder worsen with time. True immune-mediated atopy in cats can’t be cured, but it usually can be controlled with appropriate medical management and identification and removal of the inciting allergens.