Differential Diagnosis for Mononeuropathy of the Left Leg
- Single most likely diagnosis
- Peripheral nerve compression or entrapment (e.g., peroneal nerve compression): This is a common cause of mononeuropathy, especially in the legs, often due to compression or trauma to a specific nerve.
- Other Likely diagnoses
- Diabetic neuropathy: Diabetes is a well-known cause of peripheral neuropathy, which can present as mononeuropathy, particularly if the patient has poorly controlled blood sugar levels.
- Trauma: Direct injury to a nerve can cause mononeuropathy, and the history of trauma to the left leg would support this diagnosis.
- Vasculitis (e.g., vasculitic neuropathy): Inflammation of blood vessels can lead to nerve damage, presenting as mononeuropathy, though it's less common than other causes.
- Do Not Miss diagnoses
- Lyme disease: Although less common, Lyme disease can cause neuropathy, including mononeuropathy, and missing this diagnosis could lead to significant morbidity if not treated promptly.
- Sarcoidosis: This condition can cause neuropathy, including mononeuropathy, by infiltrating nerves, and it's crucial not to miss it due to its potential for serious complications.
- Tumor (e.g., schwannoma, neurofibroma): A tumor compressing a nerve can cause mononeuropathy, and missing this diagnosis could have severe consequences, including nerve damage and potential malignancy.
- Rare diagnoses
- Amyloidosis: This condition involves the deposition of abnormal proteins (amyloid) in various tissues, including nerves, leading to neuropathy, though it's a rare cause of mononeuropathy.
- Leprosy: Also known as Hansen's disease, leprosy can cause peripheral neuropathy, including mononeuropathy, especially in endemic areas, but it's rare in many parts of the world.
- Hereditary neuropathies (e.g., Charcot-Marie-Tooth disease): These are genetic disorders that affect the nerves, potentially causing mononeuropathy, though they are less common and often present with a family history.