What is seborrhea?
Seborrhea or seborrheic dermatitis is a skin disorder in which the sebaceous glands of the skin produce an excessive amount of sebum. Seborrhea typically affects the back, face and flanks causing scaly, flaky, itchy, red skin. There are two types of seborrhea, called seborrhea sicca meaning dry seborrhea, and seborrhea oleosa (oily seborrhea). Most dogs with seborrheic dermatitis have a combination of dry and oily seborrhea.
What are the clinical signs of seborrhea?
In dogs, seborrhea usually affects skin areas that are rich in sebaceous glands, especially the skin along the back. The affected areas of skin often flake off in whitish scales (dandruff) that can be seen on the dog's bedding and other places where the dog lies. Some skin areas may be red and inflamed, with either a dry or an oily feel to the lesions. The dermatitis may be worse in areas with skin folds such as the feet, neck, lips, armpits, thighs, and underside.
" Many dogs will have an odor associated with seborrhea."
Many dogs will have an odor associated with seborrhea. This odor is usually worsened if the seborrhea is complicated by a secondary bacterial or yeast skin infection.
What causes seborrhea?
In some cases, the exact cause of seborrhea cannot be determined (called idiopathic seborrhea). Seborrhea is often related to an underlying medical problem, such as:
- Hormonal imbalances - thyroid disease, Cushing's disease, etc.
- Parasites (internal and external) - fleas, ticks, mange mites
- Fungal infections - especially yeast skin infections (Malassezia)
- Dietary abnormalities - poor diets containing low levels of omega-3 fatty acids
- Environmental factors (temperature, humidity changes)
- Musculoskeletal disease or pain - the dog is unable to groom itself properly
How is seborrhea diagnosed?
Tests that can aid your veterinarian in diagnosing your dog's seborrhea include:
- Complete blood cell count (CBC), serum chemistries and electrolytes - looking for subclinical or hidden underlying conditions or imbalances
- Skin cytology and/or skin scrapings
- Skin culture - for bacterial and fungal infections, including ringworm
- Skin biopsy
- Hormone tests - including thyroid disease and Cushing's disease testing
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 seborrhea. In general, treatments that help manage seborrhea include:
- Omega-3 fatty acid supplements
- Antiseborrheic shampoos
- Oral cyclosporine
- Antibiotics - to treat secondary bacterial infections
What is the prognosis for seborrhea?
The prognosis for seborrhea is based on your dog's specific condition and severity. The prognosis is better if an underlying cause has been identified and treated. Your veterinarian will discuss a diagnostic and treatment plan for your dog to help you manage this common and often frustrating condition.