What is seborrhea?
Seborrhea, also called seborrheic dermatitis, is a skin disorder in which the skin’s sebaceous glands produce an excessive amount of sebum, which is an oily, waxy substance that helps moisturize and protect the skin. The excess sebum causes scaly, flaky, itchy, and red skin. Seborrhea typically affects the back, face, and flanks and is worse in skin folds.
There are two types of seborrhea: seborrhea sicca (meaning dry seborrhea) and seborrhea oleosa (meaning oily seborrhea). Most cats with seborrheic dermatitis have a combination of dry and oily seborrhea.
What are the clinical signs of seborrhea?
In cats, seborrhea usually affects skin areas that are rich in sebaceous glands, especially the skin along the back. Affected areas of skin often flake off like dandruff, which can be seen on the cat’s sleeping areas. Some skin areas may be red and crusty, with either a dry or oily feel to the areas.
A brown, waxy build-up may be seen on the skin surface or within the hair follicles. It may be worse in areas with skin folds, such as the feet, neck, lips, armpits, thighs, and underside. Many cats have an odor that is associated with seborrhea. This odor is usually worse if the seborrhea is complicated by a secondary bacterial or yeast skin infection.
What causes seborrhea?
Seborrhea can be a primary or secondary disease. Primary seborrhea is inherited and occurs in breeds such as Persian cats. Secondary seborrhea is more common, but the exact cause cannot always be determined. In these cases, it is called idiopathic seborrhea.
Secondary seborrhea is often related to an underlying medical problem, such as:
- Hormonal imbalances (especially hyperthyroidism)
- Allergies
- Parasites (internal and external) such as fleas, ticks, and mites
- Bacterial or yeast infections
- Dietary abnormalities (e.g., diets containing low levels of omega-3 fatty acids)
- Environmental factors (e.g., temperature, humidity changes)
- Obesity or musculoskeletal disease or pain that make the cat unable to groom properly
How is seborrhea diagnosed?
The following tests can help your veterinarian diagnose your dog's seborrhea:
- Complete blood cell count (CBC), serum chemistries, and electrolytes to look for subclinical or hidden underlying conditions or imbalances
- Skin cytology and biopsy to look for inflammatory cells, bacteria, yeast, fungus, or abnormal cells
- Skin scrapings and hair pluckings to check for external parasites
- Skin culture to test for bacterial and fungal infections (e.g., ringworm)
- Testing for underlying feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV), both of which can affect the immune system
- Hormone tests to check for hormonal imbalances (i.e., thyroid disease)
How is seborrhea treated?
Treatment is aimed at the underlying cause. If no underlying cause can be found, then a diagnosis of primary or idiopathic seborrhea is made. Unfortunately, there is no specific treatment for primary or idiopathic seborrhea. In general, treatments that help manage seborrhea include:
- Omega-3 fatty acid supplements
- Anti-seborrheic shampoos and topical treatments
- Corticosteroids
- Retinoids
- Oral cyclosporine (Atopica®)
- Antibiotics to treat secondary bacterial infections
- Antifungals if yeast infections are present
- Hypoallergenic or skin-specific diets
- Routine prevention of external parasites
What is the prognosis for seborrhea?
The prognosis for seborrhea is based on your cat’s specific condition and its severity. The prognosis is better if an underlying cause is identified and treated. Your veterinarian will discuss a diagnostic and treatment plan for your cat to help you manage this common and often frustrating condition.
