A 40 y.o. woman with a hx of brain tumor resection presents with fever and altered mental status.
Her CSF is clear yellow and her CSF protein is 350.
What causes elevated CSF protein?
Our patient had a slowly growing craniopharyngioma sp VP shunt. This is a rare benign brain tumor that originates in the pituitary. It had grown very slowly since 2007. The peak incidence rates are at ages 5-14 and ages 50-74. Patients often present with visual changes or signs of pituitary insufficiency; diabetes insipidus from lack of antidiuretic hormone, adrenal insufficiency from lack of ACTH or hypothyroidism. Our patient presented with a fever and there was concern for a shunt infection.
our patients brain tumor 7 yrs ago
Our patient had xanthochromic (yellow) CSF. This occurs when the protein is >150 or the Bilirubin is >10-15. In the case of this patient the protein was the cause of the color change with a protein documented of 350. The causes of elevated protein are many ranging from subarachnoid hemorrhage to shunt malfunction or infection.
xanthochromia
In the case of elevated CSF protein it may be useful to determine the CSF IgG/albumin ratio since albumin is not present in the CSF unless the blood brain barrier is disrupted. The more albumin present; the more the blood brain barrier is disrupted. If there is increased synthesis of immunoglobulins in the CSF, as in multiple sclerosis or neurosyphilis ,there will be an increase in the CSF IgG/albumin ratio.
Our patient was treated with antibiotics for a possible shunt infection but this was stopped when neurosurgery felt the elevated protein was from the tumor and shunt itself.
brain tumors and shunt malfunctions are also causes of elevated protein
Garnett MR, Puget S, Grill J, et al. Craniopharyngioma 2007. Ophanet Journal of Rare Diseases 2:18. Doi:10.1186/1750-1172-2-18.
Paff M, Alexandru-Abrams D, et al. Ventriculoperitoneal shunt complications: a review 2018 Interdisciplinary Neurosurgery Vol 13, 66-70.
Fishman R. Cerebrospinal Fluid in disease of the Nervous System. 1980. W.B. Saunders Co. Philadelphia.