Differential Diagnosis for Unilateral Swelling in a Post-Stroke Hemiplegic Foot

Single Most Likely Diagnosis

• Dependent Edema: This is the most common cause of unilateral swelling in a post-stroke hemiplegic foot. It occurs due to the inability to move the affected limb, leading to fluid accumulation and swelling. Justification: The patient's hemiplegia leads to decreased mobility, causing fluid to pool in the dependent limb.

Other Likely Diagnoses

• Deep Vein Thrombosis (DVT): Immobility following a stroke increases the risk of DVT, which can cause unilateral swelling. Justification: The risk factors for DVT, such as immobility and possible hypercoagulability post-stroke, make this a plausible diagnosis.
• Cellulitis: Bacterial infection of the skin and subcutaneous tissue can occur, especially if the skin integrity is compromised. Justification: The swollen, immobile limb may be more susceptible to skin breakdown and infection.
• Chronic Venous Insufficiency: This condition can lead to swelling, especially in the dependent limb. Justification: Long-standing immobility can exacerbate venous insufficiency, leading to swelling.

Do Not Miss Diagnoses

• Pulmonary Embolism (PE) with DVT: Although less common, a DVT can lead to a potentially fatal PE if not addressed promptly. Justification: The risk of PE is higher in patients with DVT, and missing this diagnosis could be catastrophic.
• Septic Arthritis or Osteomyelitis: Infection in the joint or bone can occur, especially if the patient has a history of intravenous drug use or recent surgery. Justification: These infections can be life-threatening and require prompt diagnosis and treatment.
• Compartment Syndrome: Increased pressure within the muscle compartments can lead to serious complications, including nerve and muscle damage. Justification: This condition is a medical emergency and requires immediate attention to prevent long-term damage.

Rare Diagnoses

• Lymphedema: Although less common, lymphedema can occur due to damage to the lymphatic system. Justification: This condition is rare but can cause significant swelling and discomfort.
• Malignancy: In rare cases, swelling can be a sign of an underlying malignancy, such as a soft tissue sarcoma. Justification: Although unlikely, it is essential to consider malignancy in the differential diagnosis to ensure prompt evaluation and treatment if necessary.