Differential Diagnosis for Elevated Protein in CSF without White Blood Cells
Single Most Likely Diagnosis
- Guillain-Barré Syndrome: This is an autoimmune disorder where the body's immune system mistakenly attacks part of its peripheral nervous system, leading to elevated protein levels in the cerebrospinal fluid (CSF) without a significant increase in white blood cells, a condition known as albuminocytologic dissociation.
Other Likely Diagnoses
- Spinal Cord Compression or Injury: Conditions such as spinal cord injuries, tumors, or herniated disks can cause elevated protein in the CSF due to disruption of the spinal cord tissue.
- Multiple Sclerosis: Although more commonly associated with oligoclonal bands, some cases of multiple sclerosis can present with elevated protein in the CSF without a significant pleocytosis (increase in white blood cells).
- Neurosyphilis: Especially in its late stages, neurosyphilis can cause a variety of CSF abnormalities, including elevated protein levels, often without a marked increase in white blood cells.
Do Not Miss Diagnoses
- Subarachnoid Hemorrhage: It's crucial to consider subarachnoid hemorrhage, as it can present with elevated protein in the CSF due to blood breakdown products. Although red blood cells are typically present, in some cases, especially if the sample is not promptly analyzed, the red cells may have lysed, leaving behind elevated protein and xanthochromia (yellow discoloration of the CSF).
- CNS Lymphoma: Central nervous system lymphoma can cause elevated protein in the CSF, and while it often presents with lymphocytic pleocytosis, there can be cases where the white blood cell count is not significantly elevated, especially early in the disease.
Rare Diagnoses
- CNS Sarcoidosis: Sarcoidosis affecting the central nervous system can lead to various CSF abnormalities, including elevated protein. However, this condition is less common and might not be the first consideration unless other systemic symptoms of sarcoidosis are present.
- Tuberculous Meningitis (Early Stage): In the very early stages of tuberculous meningitis, the CSF might show elevated protein with minimal or no pleocytosis, although this is uncommon and typically progresses to show a lymphocytic predominance.
- CNS Vasculitis: Vasculitis affecting the central nervous system can cause elevated protein in the CSF among other symptoms, but it is a rare condition and usually presents with a complex array of neurological symptoms and signs.