(See also Overview of Dermatitis.)
Stasis dermatitis occurs in people who have chronic swelling (edema) resulting from chronic venous insufficiency of the lower legs, which is damage to leg veins that prevents blood from flowing normally; heart failure; or lymphedema. Stasis dermatitis usually occurs on the shins but can also affect other areas that are prone to swelling such as the arms after radiation therapy to the lymph nodes.
At first, the skin is itchy, red, scaly, and thickened, usually on the shins. Eventually, areas of the skin may break down and form an open sore (ulcer). Ulcers sometimes become infected with bacteria, causing cellulitis (a bacterial infection of the skin), and are usually painful.
When chronic venous insufficiency is the cause, the skin can turn yellow-brown, varicose veins (dilated, twisted veins) usually develop, and the skin may become hard, thick, painful, and tender. This complication is called lipodermatosclerosis. Lipodermatosclerosis gives the lower leg an inverted bowling pin shape with enlargement of the calf and narrowing at the ankle.
The appearance of the skin and presence of chronic venous insufficiency
Doctors diagnose stasis dermatitis in people who have the characteristic skin changes and other symptoms of leg swelling and chronic venous insufficiency.
Sometimes more extensive evaluation and imaging tests (such as ultrasonography) are needed.
The cause of the chronic swelling is treated.
Long-term treatment is aimed at treating chronic venous insufficiency by keeping blood from pooling in the veins around the ankles. When sitting, the person should elevate the legs above the level of the heart. Properly fitted prescription support hose (compression stockings) also prevent pooling of blood and decrease swelling. Department store "support" stockings are not usually adequate.
For dermatitis that has started recently, and if there are no ulcers, a corticosteroid cream or ointment applied to the affected areas can help. If the disorder worsens, as evidenced by increased warmth, redness, oozing, or small ulcers, a more absorbent dressing, such as a hydrocolloid dressing, can be used.
In stasis dermatitis, the skin is easily irritated. Antibiotic creams, first-aid (anesthetic) creams, wool alcohols, witch hazel, lanolin, or other chemicals should not be used because they can make the disorder worse.
Ulcers are best treated with compresses and dressings made with zinc oxide paste. Special moisture-absorbing hydrocolloid or hydrogel dressings also may be used.
Some people may need an Unna paste boot, which is a woven stretch wrap filled with a gelatin paste that contains zinc. The wrap is applied to the ankle and lower leg where it hardens, similar to but softer than a cast. The boot limits swelling and helps protect the skin from irritation, and the paste helps heal the skin. At first the boot is changed every 2 or 3 days, but later it is changed only once or twice a week. After the ulcer heals, an elastic support should be applied before the person rises in the morning. Regardless of the dressing used, reduction of swelling (usually with compression) is essential for healing.
Antibiotics applied to the skin are useful for treating some open or irritated areas of skin and ulcers. Antibiotics given by mouth are used to treat cellulitis. Sometimes, skin from elsewhere on the body may be grafted to cover very large ulcers.