Leg ulcers

Probability diagnosis

Venous insufficiency 52%

Arterial insufficiency 13%

Mixed arterial and venous disease 15%

Pressure sore

Trauma with chronic infection

Systemic disease esp. diabetes

Secondary to peripheral oedema

Serious disorders not to be missed

Vascular:

• Skin infarction (thrombotic ulcer)

• Vasculitis-RA, SLE, scleroderma

Infection:

• Post herpetic ulcer

• Tuberculosis

• HIV/AIDS

• Tropical ulcer

• Post cellulitis

Cancer:

• Primary-SCC, melanoma, malignant change in ulcer

• Secondary-ulcerating metastases

Other:

• Haematological e.g. sickle cell

• Chronic scarring—sun damaged skin

• Pyoderma gangrenosum

Pitfalls (often missed)

Insect and spider bites

Factitious (neurotic excoriations)

Rarities:

• Tropical infections e.g. leprosy

• Myobacterium ulcerans

Masquerades checklist

Diabetes: neurotrophic

Drugs—systemic reaction

Anaemias: hereditary anaemias

Is the patient trying to tell me something?

Consider: Factitious ?dermatitis artefacta ?neurotic excoriation

Key history

Look for a cause: venous—previous DVT, varicose veins; peripheral arterial disease. Seek history of systemic disease such as diabetes, inflammatory bowel disease, connective tissue esp. RA. Check for a history of intermittent claudication or ischaemic rest pain; chronic ulcers including sun damage; tropical residence. Include a drug history, esp. beta blockers, corticosteroids, ergotamine, nifedipine.

Key examination

• General features: appearance of patient, vital signs esp. temperature

• Full cardiovascular assessment esp. lower limb

• Assess characteristics of the ulcer, esp. shape, edge, floor, discharge, surrounding skin, regional lymph nodes

• Neurotip or similar for skin sensation

Key investigations

First line:

• FBE

• ESR/CRP

• blood sugar

Consider:

• wound swabs (if evidence infection)

• duplex ultrasound

• ankle brachial index

• biopsy

• KFTs

Diagnostic tips

Be cautious of almenotic melanoma if undertaking biopsy. If the ulcer and site is painful, consider arterial insufficiency.