Swollen Ankles
Differential Diagnosis
Common Diagnoses
- Congestive Cardiac Failure (CCF)
- Drug Reaction: Especially Calcium Antagonists
- Gravitational (Venous Insufficiency, Often with Poor Mobility)
- Obesity
- Pelvic Mass (Including Pregnancy)
Occasional Diagnoses
- Cirrhosis
- Premenstrual Syndrome
- Anaemia
- Renal: Acute or Chronic Nephritis, Nephrotic Syndrome
- Protein-Losing Enteropathy (e.g. Coeliac Disease, Inflammatory Bowel Disease)
Rare Diagnoses
- Malnutrition
- Inferior Vena Cava Thrombosis
- Filariasis
- Milroy’s Disease (Hereditary Lymphoedema)
- Ancylostomiasis (Hookworm)
Ready Reckoner
Key distinguishing features of the most common diagnoses
| CCF | Drug Reaction | Gravitational | Obesity | Pelvic Mass | |
|---|---|---|---|---|---|
| Shortness of Breath on Exertion | Yes | No | No | Possible | Possible |
| Altered Breath Sounds | Yes | No | No | No | No |
| Less Swollen in the Morning | Possible | Possible | Yes | Possible | Possible |
| Taking Oedema-Genic Drug | Possible | Yes | No | No | No |
| Other Symptoms or Signs | Yes | No | No | No | Yes |
Possible Investigations
Likely:Urinalysis, FBC, U&E, LFT, BNP.
Possible:ECG, TFT, echocardiography.
Small Print:CXR, pelvic ultrasound, further investigation of underlying cause.
- Urinalysis: For proteinuria.
- FBC: Look for anaemia of chronic disorder, raised MCV (alcohol abuse).
- U&E: Will reveal underlying renal failure; sodium low in CCF and cirrhosis.
- LFT: May reveal hypoproteinaemia (e.g. in cirrhosis, protein-losing enteropathy and nephrotic syndrome).
- BNP: Likely to be elevated in heart failure.
- ECG: In heart failure, may show signs of left ventricular hypertrophy, ischaemia or arrhythmia.
- Echocardiography: To confirm suspected heart failure.
- CXR: Pulmonary oedema and pleural effusion in CCF.
- Pelvic ultrasound: For pelvic mass.
- Further investigation of underlying cause: This might involve CT scan (pelvic mass), renal biopsy (nephritis) and bowel investigations (enteropathy).
Top Tips
- In the elderly, the cause is often multifactorial, with immobility playing a major role.
- Proper assessment can take time – consider spreading the work over a couple of consultations, using the intervening time to arrange and assess investigations.
- Ankle swelling is usually symmetrical, though venous insufficiency in particular can affect one side much more than the other. But if only one ankle is swollen, consider deep vein thrombosis, a ruptured Baker’s cyst or cellulitis.
- Don’t forget that many drugs (such as calcium antagonists and NSAIDs) can cause marked ankle swelling.
Red Flags
- If no cause is obvious in an elderly person, examine the abdomen and also consider a rectal examination.
- The younger the patient, the greater the chance of significant pathology – especially renal.
- Marked swelling of recent and sudden onset is likely to be significant regardless of age.