Lumbar puncture in a 45-year-old man yields cerebrospinal fluid that is yellow-tinged, has a protein concentration of 600 mg/dL, and clots spontaneously in the tube. Cell count shows only 8 lymphocytes/uL. The most likely cause of these findings is:
- A Complete block of spinal CSF flow by an extradural tumor ✓
- B Acute bacterial meningitis
- C Recent subarachnoid hemorrhage
- D Guillain-Barre syndrome
Correct answer: A. Complete block of spinal CSF flow by an extradural tumor
Explanation
Xanthochromia with very high protein and spontaneous clotting defines Froin syndrome, caused by stagnation of CSF below a complete spinal subarachnoid block, classically an extradural tumor or adhesive arachnoiditis. Guillain-Barre raises protein but does not produce clotting or marked xanthochromia. In subarachnoid hemorrhage the xanthochromia comes from bilirubin released after red cell lysis, and protein elevation is modest. Bacterial meningitis would show neutrophilic pleocytosis.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.