I. Problem/Condition.

Leg ulcers are a common problem. Infections, vascular diseases, connective tissue and hematologic disorders and metabolic disorders such as calciphylaxis can all cause lower extremity ulceration. Chronic venous disease is by far the most common cause of lower extremity ulceration, however, the differential diagnosis is broad and many are multifactorial in etiology given that peripheral arterial disease and lower extremity neuropathy are both common in diabetic patients. The cost of non-healing ulcerations of the lower extremities is enormous given the expertise, equipment and time to full healing. Estimates of the cost of venous ulceration alone in the United States range from $2-3 billion per year.

II. Diagnostic Approach.

A. What is the differential diagnosis for this problem?

  • Vascular causes: chronic venous disease, peripheral arterial disease, cholesterol emboli

  • Infections: mycobacterial infection, cryptococcal disease, osteomyelitis, ecthyma gangrenosum

    Continue Reading

  • Hematologic: disseminated intravascular coagulation, essential thrombocythemia, polycythemia vera, sickle cell anemia, leukemia

  • Medication-induced: heparin-induced thrombocytopenia, warfarin skin necrosis,

  • Autoimmune: rheumatoid arthritis, Wegener’s granulomatosis, cryoglobulinemia, antiphospholipid antibody syndrome

  • Neoplastic: squamous cell carcinoma, cutaneous T cell lymphoma

  • Pyoderma Gangrenosum

SeeTable I

Table I.
Type of ulcer General characteristics Ulcer appearance Location Other findings
Venous Most common type; accounts for ~80% of ulcers Shallow, irregular borders. Red base with yellow fibrous tissue Over bony prominences Hyperpigmented skin, varicose veins, edema, lipodermatosclerosis
Arterial/Ischemic Occurs in patients who often have a history of atherosclerotic disease Well-demarcated and deep. Can appear “punched out” Occurs over bony prominences Cool, hairless extremity, absence of peripheral pulses
Neuropathic Commonly occur on feet in diabetic patients Non-painful, well-demarcated with callous formation around ulcer Areas of pressure or repetitive trauma or pressure Decreased sensation or proprioception in lower extremity
Pyoderma Gangrenosum Often occurs in patients with underlying inflammatory disorders (IBD, arthritis, myeloproliferative d/o) Starts as a pustule or bulla; rapidly progressing, painful with edematous, violaceous, undermined border. Usually on the shin but can appear anywhere Findings of other systemic disease such as inflammatory arthritis.

B. Describe a diagnostic approach/method to the patient with this problem.

History and physical exam are vital to distinguishing between different types of ulcers. Occasionally laboratory and other diagnostic tests can be helpful but much of the time a diagnosis can be established by history and physical alone.

1. Historical information important in the diagnosis of this problem.

  • Over what time course did the ulcer develop?

  • Does the patient have claudication?

  • Is the ulcer painful? If so, what type of pain?

  • Is discomfort relieved or exacerbated by elevating leg?

  • Does the patient have other systemic illnesses?

  • Does the patient have a history of smoking cigarettes?

  • Presence of chronic medical conditions such as diabetes, connective tissue diseases, other vascular disease.

  • History of previous ulcerations.

  • Current medications.

2. Physical Examination maneuvers that are likely to be useful in diagnosing the cause of this problem.

Physical exam should focus on examination of the ulceration(s) and a general physical exam to evaluate for other signs of systemic illness. Below are important findings to note on physical examination.

  • Location of ulceration (over malleoli, in areas of repetitive trauma or pressure

  • Appearance of ulceration – irregular or well-demarcated borders, color, presence of suppuration or granulation

  • Skin findings on lower extremity (presence or absence of hair, hyperpigmentation, stasis dermatitis, lipodermatosclerosis)

  • Presence of varicose veins

  • Vascular exam (peripheral pulses)

  • Sensory exam

  • General exam including cardiovascular, pulmonary and musculoskeletal systems.

  • Ankle brachial indexes can be performed if peripheral vascular disease is suspected.

3. Laboratory, radiographic and other tests that are likely to be useful in diagnosing the cause of this problem.

Laboratory studies

  • Complete blood count and comprehensive metabolic panel are useful in looking for signs of other systemic disease or infection.

Xrays are useful only if suspected osteomyelitis and may be negative in early osteomyelitis.

Vascular studies are indicated in ulcers suspected to be of ischemic origin and in certain patients with diabetic ulcerations.

  • Ankle-brachial indices

  • Segmental lower extremity pressures

  • CT angiography

  • Magnetic resonance angiography

  • Traditional angiography by peripheral arterial disease specialist

If suspicious of pyoderma gangrenosum or etiology other than venous, ischemic or neuropathic ulcers, skin biopsy can be helpful.

III. Management while the Diagnostic Process is Proceeding.

A. Management of Clinical Problem Leg Ulcers.

Prevention of ulceration is the best treatment.

Venous ulcers:

  • Compression:is the mainstay of treatment and prevention of venous ulcerations.

    Unna boot: a zinc oxide-impregnated moist bandage that hardens after application; it is a form of inelastic compression in which high pressure is applied during walking and muscle contraction but no resting pressure is applied.

    Compression stockings

    Elastic compression bandages

2. Elevation: elevation of leg above the level of heart to improve blood flow back to heart

3. Local wound care: as recommended by wound care specialist.

4. Treatment of infection: if present

5. Superficial vein surgery has been studied and may be effective at preventing ulcer recurrence but not in management of an already established ulcer.

Arterial/ischemic ulcers:

  • Evaluation of lower extremity vasculature

    Ankle-brachial indices

    CT angiography

    Segmental lower extremity pressures

    Magnetic resonance angiography

    Contrast angiography

  • Referral to vascular specialist (interventional cardiologist/PAD specialist, interventional radiology or vascular surgeon) for consideration of revascularization

  • Smoking cessation

  • Lipid lowering therapy with goal LDL <100mg/dL in patients without evidence of other cardiovascular disease and <70mg/dL in patients with concomitant coronary artery disease.

  • Antiplatelet therapy

  • Control of hypertension

    In patients with diabetes or chronic kidney disease goal blood pressure is <130/80

    In all other patients the goal blood pressure is <140/90 unless other comorbidities exist requiring tighter control of blood pressure

Diabetic ulcers:

1. Prevention: counseling patients on proper foot care is the mainstay of treatment.

  • Do not walk barefoot

  • Do not wear ill fitting shoes

  • Examine feet daily for cracks, blisters, beginning of ulceration

  • Smoking cessation

  • Wash and moisturize feet daily

  • Trim toenails to avoid sharp edges and ingrown toenails

B. Common Pitfalls and Side-Effects of Management of this Clinical Problem.

The presence of ischemic disease (peripheral vascular disease) is often overlooked in patients with diabetic neuropathic foot ulcers. In fact, these ulcers are often neuroischemic ulcers and vascular evaluation and referral to vascular specialists is underutilized in this population.