An Approach to an Open Wound
Doctor, I have an ulcer on my skin!
Introduction
Differential Diagnosis
Lower Limb Ulceration
Medical Causes of Skin Ulceration
What Is The Diagnosis?
Help! The Ulcer / Wound Isn't Healing As Expected! What's Going On?
Context: Outpatients
Introduction
Surgeons are frequently asked to review or manage patients with wounds, particularly if they don't seem to be healing as expected. No matter where the problem is, the are six questions you need to explore when taking history:
| Question | Context |
| Where is it? | The clinical implications and differential diagnosis are very different depending on where it is! The great majority occur on the lower limb. |
| When and how did it come about? | Was this the result of obvious trauma, or a presumed “insect bite”? Is this a post-operative event or has it arisen spontaneously? When was it first noticed? |
| How has it changed since you first noticed it? | Has it got bigger, smaller, stayed the same size or has it come and gone? Has it changed its appearance and consistency? |
| What symptoms does it cause you? | Is it painful? Does it cause any other symptoms? Is there a discharge of pus or fluid? |
| Have you got any more/had it before? | If the patient has more than one skin ulcer, are they the same? If the patient has had this before, what happened to it the last time, and what did the doctor say it was? |
| What medical conditions do you have? | Are the patients immunocompromised, diabetic, malnourished? Is there vascular or connective tissue disease? Has the patient event been diagnosed with cancer or received radiotherapy? |
Differential Diagnosis
A practical consideration is to divide the causes in "medical" and "surgical" conditions.
The great majority of non-healing "surgical" ulcers are seen in the lower limb, but they may occasionally present at other anatomical sites, and the common causes to consider at different sites are listed below.
| Location | Common | Don't want to miss |
| Face / Neck | Skin carcinoma (BCC, squamous, melanoma) | TB sinus |
| Axilla | Hidrenitis suppurativa | TB sinus |
| Breast | Periductal mastitis | Breast cancer, TB |
| Perianal Region | Veneral disease Perianal fistula | Anal cancer |
| Sacrum | Pressure ulcer Pilonidal sinus | |
| Abdominal Wall | Wound infection | Intestinal fistulae |
Lower Limb Ulceration
90% of leg ulcers are due to either arterial, venous or neuropathic conditions, the latter almost always in diabetic patients. Neuropathic ulcers and arterial disease often co-exist, particularly in diabetics, and render their management very complex.
Common Causes
| Ischaemic Ulcer | |
| Site | Tips of the toes or on pressure areas (Heel malleoli and shin) |
| Appearance | Well-demarcated edges, giving them a "punched-out" appearance, often with an overlying necrotic eschar, arterial ulcers typically are very painful |
| Other Clinical Features | Thin atrophic legs, absent pulses, early tissue loss, smokers |
| Venous Ulcer | |
| Site | Above the medial malleolus |
| Appearance | Ulcers are typically shallow with irregular borders with yellow, fibrinous exudate overlying the wound bed. Pain is mild to moderate |
| Other Clinical Features | Normal pulses. Often swollen legs with signs of chronic venous insufficiency (telangiectasias, peripheral oedema, venous varicosities, lipodermatosclerosis) |
| Neuropathic | |
| Site | Pressure points on the foot or heel |
| Appearance | Ulcers have a punched-out morphology and typically occur within a thick callus Painless |
| Other Clinical Features | Diabetic neuropathy=claw toes, neuropathic (Charcot) arthropathy, and reduced sweating resulting in dry, scaly feet |
Occasional Scenarios
| Scenario | Causes | Features |
| Trauma | Pressure injuries, burns, radiation exposure, brown button spider bites, dog bites, iatrogenic injury or self-induced injury | Varied appearance, the common site is the anterior shin, which is very slow to heal in elderly patients. Appearance varies from shallow open ulcers to deep ulcers that expose bone, tendon or muscle |
| Infections | Staph aureus, impetigo, furuncles | Poor hygiene, multiple flea or insect bites |
| Chronic osteitis | Previous trauma, non-healing fracture, purulent sinus discharge |
Very Uncommon Scenarios
| Scenario | Causes | Features |
| Malignancy | Long standing ulcers can undergo squamous malignant change: “Marjolin ulcer” | Rolled prominent edges, with chronic exudate, increasing in size |
| Advancer sarcomas may ulcerate | Ulcer with large underlying mass | |
| Weird infections | Atypical mycobacterial, late-stage syphilis (gummas), deep fungal infections (e.g., coccidiomycosis, blastomycosis, histoplasmosis) and protozoal infections (e.g. leishmaniasis) | Unusual history of travel, immunocompromised patient |
| Medical causes | Systemic disease/dermatological conditions | - |
Remember that some systemic medical conditions may have unusual dermatological components! None of these are common, but you need to remember that they exist, and think of them in atypical cases.
Medical Causes of Skin Ulceration
| Medical cause | Associated condition | Typical clinical feature |
| Vasculitis | Infections, drugs, mixed cryoglobulinemia, autoimmune disorders (SLE, rheumatoid arthritis, Sjögren syndrome), or hematologic malignancies. | Palpable purpura may develop an overlying necrotic vesicle or bulla that becomes ulcerative. |
| Microvascular occlusion disorders | Associated with cryoglobulinaemia, oxalosis, calciphylaxis in secondary hyperparathyroidism | Cutaneous ulcerations, typically are very painful and retiform purpura |
| Pyroderma gangrenosum | Inflammatory bowel disease, arthritis, or hematologic disease | Single or multiple rapidly progressive painful leg ulcers with necrotic borders and surrounding erythema. The initial clinical finding is a pustule, which then develops an overlying necrotic bulla that ulcerates with purulent drainage |
| Drug reaction | Warfarin, heparin, hydroxyl-urea | Pain is the initial symptom, followed by erythema, which then becomes haemorrhagic and necrotic. Retiform purpura may be adjacent to sites of skin necrosis |
| Panniculitis | Associated with a pancreatic disease, alpha1 antitrypsin deficiency | Inflammation of the subcutaneous fat, followed by ulceration |
What Is The Diagnosis?
In almost all circumstances the diagnosis of the ulcer is very obvious on clinical grounds alone and does not require formal investigations.
Occasionally a biopsy of the ulcer edge is performed to exclude malignancy; tissue culture or pus swabs can be done to look for unusual infections.
In practice most tests are aimed at evaluating the severity of the underlying cause, and what can be done to treat that condition.
| Ulcer Type | Investigations | Intervention | Natural history |
| Ischaemic | Evaluate co-morbidity Arterial doppler Duplex doppler/angiography | Bypass, endovascular intervention vs limb ablation | Will never heal unless ischemia is corrected |
| Venous | Venous dopplers exclude arterial disease | Local hygiene, long term compression bandaging Venous surgery occasionally helpful | An indolent, relapsing course |
| Neuropathic | Evaluate concomitant arterial disease. | Optimise diabetic Mx Unload pressure area Treat ischaemia May need debridement or ablation | Problematic, healing is uncommon |
Help! The Ulcer / Wound Isn't Healing As Expected! What Is Going On?
All wounds heal, in well-nourished healthy individuals, irrespective of the dressings done to facilitate it. Time heals.
However, some patients fail to match the clinical expectation and have persistent, open wounds. In these cases consider two key factors:
- What is the underlying diagnosis (cause of the ulcer)? Am I treating this cause correctly? Am I missing something?
- Are there local or systemic factors that are delaying the healing process?
| Local factors | Systemic factors |
| Local ischaemia | Malnutrition |
| Chronic sepsis | Immunocompromised (diabetes, Cushing's, HIV) |
| Entero-cutaneous fistula or chronic sinus | Drugs (steroids, chemotherapy, immune suppressant drugs) |
| Retained foreign body | Connective tissue disease |
| Radiotherapy | Ageing |
| Malignancy | Immobilization |
| Anatomy (certain sites like the heel or anterior tibial skin are very slow to heal) | Smoking |
| Repeated trauma or friction | Oedema (CCF, CRF, liver failure) |
| Fictitious / patient interference | Chronic hypoxia (COPD) |