Differential Diagnosis for 77-year-old Female with Sudden Onset of Left Lower Leg Weakness
- Single Most Likely Diagnosis
- Peripheral Artery Disease (PAD) with Acute Limb Ischemia: Given the patient's age, hypertension, and sudden onset of leg weakness and numbness, PAD with acute limb ischemia is a highly plausible diagnosis. The antalgic gait suggests pain on walking, which is consistent with intermittent claudication, a symptom of PAD. However, the sudden onset of symptoms could indicate an acute occlusion.
- Other Likely Diagnoses
- Lumbar Radiculopathy: Compression or irritation of the lumbar nerve roots could cause leg weakness, numbness, and pain, leading to an antalgic gait. This condition is common in the elderly due to degenerative changes in the spine.
- Stroke or Transient Ischemic Attack (TIA): Although less likely given the localized symptoms to one leg, a stroke or TIA affecting the motor cortex or its pathways could present with unilateral weakness. The absence of other typical stroke symptoms (e.g., facial weakness, speech difficulties) makes this less likely but still a consideration.
- Diabetic Neuropathy: If the patient has diabetes, neuropathy could cause numbness and weakness, although the sudden onset would be less typical for this condition.
- Do Not Miss Diagnoses
- Aortic Dissection: Although rare, an aortic dissection could lead to acute limb ischemia if the dissection involves the iliac or femoral arteries. This condition is life-threatening and requires immediate intervention.
- Spinal Cord Infarction: This is a rare but potentially devastating condition that could present with sudden onset of leg weakness and numbness. It is often associated with aortic disease or other vascular pathologies.
- Deep Vein Thrombosis (DVT): While DVT typically presents with swelling and pain, in some cases, especially if there is associated nerve compression or a large clot, it could cause weakness and numbness.
- Rare Diagnoses
- Vasculitis (e.g., Giant Cell Arteritis, Takayasu Arteritis): These conditions are rare and typically present with systemic symptoms, but they could cause limb ischemia or neuropathy in advanced cases.
- Neoplastic or Paraneoplastic Syndromes: Rarely, a tumor or paraneoplastic syndrome could cause localized neurological deficits, including leg weakness and numbness.
- Infectious or Inflammatory Myopathies: Conditions like polymyalgia rheumatica or infectious myositis could cause muscle weakness, but the presentation would typically be more systemic and less localized to one leg.