Extreme hypoglycorrhachia: Not always bacterial meningitis

Background. A 55-year-old man presented with 4 months of chronic meningitis, neutrophilic pleocytosis and extreme hypoglycorrhachia-an abnormally low concentration of glucose in the cerebrospinal fluid (CSF). A previous neurological work-up had revealed no noteworthy abnormalities. Despite the brief improvements that were seen after numerous trials of antibiotics and corticosteroids, the symptoms relapsed soon after corticosteroids were discontinued. Lumbar puncture revealed cholesterol crystals in the CSF and imaging studies revealed a sickle-shaped sacrum, partial rectal stenosis, and a communicating presacral meningocele with an epidermoid-dermoid mass. Extreme hypoglycorrhachia seems almost always to be bacterial in origin, but its differential diagnosis is, nevertheless, extensive. The definition, physiology, pathophysiology and differential diagnosis of hypoglycorrhachia are reviewed here. Investigations. Physical examination, laboratory testing, multiple imaging studies including CT and MRI of the brain and spinal cord, as well as myelography and CSF analysis. Diagnosis. Cholesterol-induced leptomeningitis in a patient with Currarino syndrome, a triad that consists of sacral bone defects, congenital hindgut anomaly, and a presacral tumor. Management. The patient was initially treated with multiple antimicrobials and steroids. However, once the cholesterol crystals and communicating presacral cyst were identified, the condition was successfully managed with surgically resection of the cyst.