-IBIS-1.5.0-
tx
cutaneous system
skin ulcer
diagnoses

definition and etiology

definition:
an excavation of the surface of the skin produced by sloughing of necrotic inflammatory tissue

etiology:
There are six stages of ulcer formation:
• skin redness that disappears with pressure; skin and subdermal tissues are still soft
• skin redness, edema, induration with occasional epidermal desquamation or blistering
• skin necrosis, exposing fat
• necrosis extends beyond the skin and fat into the muscle
• increased fat and muscle necrosis
• necrosis extends into the bone, causing destruction and infection (periostitis and osteitis) that leads to osteomyelitis; this stage can continue, possibly worsening into septic arthritis, pathological fracture, and septicemia

three specific ulcer types:
decubitus ulcer (aka bedsore; pressure sore; trophic ulcer):
This type of ulcer occurs when tissue over a bony prominence dies and sloughs off following chronic pressure from an external object. It is associated with patients who are bedridden for a long time, or who have decreased or no sensation, are debilitated, or are emaciated. The areas over which bedsores most frequently appear include the sacrum, greater trochanters, ischia, heels, and external malleoli; other sites are possible. Risk factors are either intrinsic (e.g. loss of pain sensation, decreased fat and muscle padding, malnutrition, infection, decreased circulation from disuse of muscles) or extrinsic (e.g. pressure, moisture causing maceration, and friction).
peripheral vascular disorder ulcer (peripheral atherosclerotic disease, arteriosclerosis obliterans): caused by atherosclerotic plaques that decrease blood flow to the extremities. It is the chronic, insidious ischemia that predisposes to ulcer formation, which follows a history of intermittent claudication; it usually occurs in the lower legs.
stasis ulcers (venous insufficiency): result from chronic venous insufficiency, usually following deep thrombophlebitis or severe varicose veins of long duration.

signs and symptoms

decubitus ulcer
signs and symptoms:
• bed-ridden patient
• skin ulceration in any of the above stages
• patient has urinary or fecal incontinence (higher risk for ulceration)

peripheral vascular disorder ulcer
signs and symptoms:
• decreased or absent pulses
• foot is painful, cold, numb
• poor nail growth in toes
• hairs fall out
• dry, scaly skin
• ulceration: typically on toes, heel, occasionally the leg
• no edema
• leg may be atrophied and shrunken

lab findings:
• (+) angiography for occlusions
• (+) arteriography
• (+) Doppler ultrasound
• (+) blood chemistries for high blood lipids

stasis ulcer
signs and symptoms:
• stasis dermatitis: persistent inflammation of the skin of the lower legs; skin turns brown; slight scaling occurs
• frequently the patient has a history of edema and/or varicose veins and/or thrombophlebitis
• area usually affected is the lateral aspect of the lower leg and ankle
• ulceration: perhaps with secondary infection

lab findings:
• (+) venogram
• (+) Doppler ultrasound
• (+) plethysmography
• (-) culture apart from normal skin flora

course and prognosis

decubitus ulcers: The best treatment is prevention; long-term pressure over bony areas must be relieved. The patient's skin must be frequently checked for the early signs of a developing ulcer and must be kept clean and dry (of sweat, urine, feces). Activity should be encouraged, and a healthy diet maintained. Ulcers in stages 1-3 will heal spontaneously if such attention is directed towards them. Once an ulcer has progressed far enough (4th stage and beyond), debridement is necessary. More in-depth surgery may be required to prevent a deepening ulceration that may lead to serious infection or death.

peripheral atherosclerotic disease: Treatment consists of prophylaxis and preventive measures (foot inspection, feet cleaned daily). Anti-atherosclerotic treatment including diet and exercise may aid oxygenation of ischemic tissue. Where the problem is serious, reconstructive surgical procedures may be effective, and may be indicated to prevent amputation.

stasis ulcers: Treatment consists of topical applications and focuses on increasing venous return from the lower legs and feet. Untreated or severe disease may require surgical intervention or amputation.

differential diagnosis

• other ulcerating skin conditions


footnotes