Differential Diagnosis for Acute Onset of Severe Pain and Paresthesias in the Right Calf
- Single most likely diagnosis
- Arterial thromboembolism: This is the most likely diagnosis given the patient's history of paroxysmal atrial fibrillation, which is a significant risk factor for thromboembolic events. The acute onset of severe pain and paresthesias in the right calf, along with lower extremity pallor and an absent dorsalis pedis pulse, suggests an embolic event occluding a peripheral artery.
- Other Likely diagnoses
- Arterial thrombosis: While less likely than thromboembolism in this context, arterial thrombosis could still occur, especially if there are underlying atherosclerotic lesions. However, the absence of a more gradual onset of symptoms makes this less probable.
- Arterial atheroembolism: This condition, also known as cholesterol crystal embolization, typically occurs after an invasive vascular procedure or with severe atherosclerotic disease. The presentation can be similar to thromboembolism but usually involves more systemic symptoms and a history of recent vascular intervention.
- Do Not Miss diagnoses
- Popliteal artery entrapment syndrome: Although rare and less likely given the acute presentation, this condition involves compression of the popliteal artery due to anatomical anomalies. It typically presents in younger individuals with a history of exercise-induced claudication but could potentially cause acute limb ischemia if the compression is severe.
- Arterial vasospasm: This could be a consideration, especially if there's a history of Raynaud's phenomenon or other vasospastic disorders. However, the severity of symptoms and the absent pulse suggest a more obstructive cause.
- Rare diagnoses
- Other rare embolic sources: These could include paradoxical embolism through a patent foramen ovale, tumor embolism, or embolism from other cardiac sources like a cardiac myxoma.
- Vasculitis: Conditions like Buerger's disease or other forms of vasculitis could present with acute limb ischemia but are less common and typically have additional systemic symptoms or a more gradual onset.