Differential Diagnosis for Bilateral Cauda Equina Enhancement
Single Most Likely Diagnosis
- Chronic Inflammatory Demyelinating Polyneuropathy (CIDP): This condition is characterized by demyelination of the peripheral nerves, which can lead to bilateral cauda equina enhancement and sciatic nerve enlargement. Elevated CSF protein levels without viral screening positivity support this diagnosis, as CIDP often presents with high protein levels in the cerebrospinal fluid.
Other Likely Diagnoses
- Guillain-Barré Syndrome: Although typically presenting with a more acute onset, some forms of Guillain-Barré Syndrome can have a subacute progression, leading to bilateral cauda equina enhancement and elevated CSF protein levels. The absence of viral screening positivity does not rule out this diagnosis, as the syndrome can be post-infectious.
- Neurosyphilis: This condition can cause a range of neurological symptoms, including cauda equina syndrome. While less common, neurosyphilis should be considered, especially if other explanations are ruled out, and it can present with elevated CSF protein levels.
Do Not Miss Diagnoses
- Lymphoma or Leukemia Involvement: Malignant infiltration of the cauda equina can cause enhancement and neurological symptoms. Although less likely, missing this diagnosis could be catastrophic, making it crucial to consider and rule out with appropriate imaging and CSF analysis.
- Spinal Subarachnoid Hemorrhage: Although the presentation might not fully align, a spinal subarachnoid hemorrhage could potentially cause cauda equina enhancement and elevated CSF protein levels. This condition requires urgent diagnosis and treatment.
Rare Diagnoses
- Sarcoidosis: Neurosarcoidosis can affect any part of the nervous system, including the cauda equina, leading to enhancement on imaging. It is a rare condition but should be considered if other diagnoses are ruled out, especially in the context of systemic symptoms.
- Infectious Meningitis (e.g., Fungal or Tuberculous): While viral screening was negative, other types of infectious meningitis could present with similar findings. These conditions are less common but critical to diagnose due to their treatment implications and potential for severe outcomes.