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STASIS
DERMATITIS
Stasis
dermatitis is characterized by scaly, greasy looking skin on the lower
legs and around the ankles. Stasis dermatitis is most apt to affect the
inner side of the calf and is generally related to circulatory problems This
type often occurs with varicose veins. Stasis dermatitis may cause the
skin at your ankles and over your shins to become discolored (red or
brown), thick and itchy. Stasis
dermatitis can occur when fluid accumulates in the tissues just
beneath your skin. Varicose veins and other chronic conditions in your
legs can cause the fluid buildup. This swelling (edema)
is caused when plasma (the fluid portion of blood) leaks out of the
blood vessels and into the tissues. The excess fluid in the tissues
interferes with the blood's ability to feed the tissue cells and dispose
of cellular waste products. The tissue becomes poorly nourished and
fragile, resulting in stasis dermatitis. The disorder is common on the
ankles because there is less supportive tissue in this area. Stasis
dermatitis causes a red, itchy rash on the lower legs. The rash can be
dry and scaly or can weep and form crusts. The skin may turn to a brown
or purple color, and the lower legs may swell. As the skin becomes thin
and inflamed, open ulcers may form
and heal slowly. The skin, initially thin, may later thicken, perhaps
because of itching
and scratching of the area. Stasis dermatitis is usually caused by poor blood flow from the veins of the legs back to the heart. It is seen most often in middle-aged people or people who are elderly. The poor blood flow may be associated with the following conditions:
The
rash is often made worse by the use of salves or ointments. It may be
aggravated by infection with bacteria or fungus. Elevating
the ankle above the heart while resting (to increase venous return and
prevent tissue swelling), wearing properly fitted support hose, and
applying topical therapy are necessary. However, unless circulation
improves, these approaches will be relatively ineffective. The choice of
topical therapy depends on the disease stage. For acute stasis
dermatitis, continuous and then intermittent tap-water compresses should
be applied. For an exudative lesion, a more absorbent hydrocolloid
dressing may be the best treatment. For less acute dermatitis, a
corticosteroid cream or ointment may be prescribed or incorporated into
zinc oxide paste. Oral
antibiotics are useful when cellulitis is present; topical antibiotics
are useless and often cause contact dermatitis. Complex
or multiple topical drugs or nonprescription remedies should not be
used: The skin in stasis dermatitis is more vulnerable to direct
irritants and to potentially sensitizing topical agents (antibiotics;
anesthetics; vehicles of topical drugs, especially lanolin or wool
alcohols). Involved
skin in stasis dermatitis may exhibit the same changes as seen in other
eczema conditions. Severe, acute inflammation may result in exudative,
weeping patches and plaques. Secondary infection can cause typical
honey-colored crusting due to bacteria, or monomorphous pustules due to
cutaneous candidiasis. In long-standing lesions, lichenification and
hyperpigmentation may occur as a consequence of chronic scratching and
rubbing. In
addition to lichenification and hyperpigmentation, chronic stasis
dermatitis can show changes such as skin induration, which may progress
to lipodermatosclerosis with the classic "inverted champagne
bottle" appearance. Another unique feature sometimes seen in
chronic stasis dermatitis is the development of violaceous plaques and
nodules on the legs and dorsal feet. These lesions frequently undergo
painful ulceration and can be clinically indistinguishable from classic
Kaposi sarcoma. This clinical appearance has led this entity to be
called "pseudoKaposi sarcoma" or acroangiodermatitis. The
excess fluid in the tissues interferes with the blood's ability to feed
the tissue cells and dispose of cellular waste products. The tissue
becomes poorly nourished and fragile, resulting in stasis dermatitis.
The disorder is common on the ankles because there is less supportive
tissue in this area. Stasis
dermatitis is often a chronic condition.
Symptoms may be minimized if the underlying condition and edema
can be controlled. Complications include:
Stasis dermatitis should clear up with effective treatment. However, the discolored skin rarely returns to its normal color. |