CSF analysis in a patient with suspected chronic meningitis shows 60 lymphocytes per microliter, protein 250 mg/dL, glucose 25 mg/dL with simultaneous blood glucose of 110 mg/dL, and opening pressure of 30 cm H2O. MRI shows thick basal exudates with nodular enhancement and communicating hydrocephalus. The most likely diagnosis is:

• A Cryptococcal meningitis
• B Herpes simplex encephalitis
• C Tuberculous meningitis ✓
• D Bacterial meningitis due to Streptococcus pneumoniae

Explanation

Lymphocytic pleocytosis with markedly elevated protein, very low glucose, raised opening pressure, and basal meningeal enhancement with hydrocephalus is characteristic of tuberculous meningitis, reflecting thick gelatinous basal exudates around the circle of Willis. Cryptococcus also causes low glucose but typically shows fewer organisms on India ink rather than nodular basal enhancement. Pneumococcal meningitis gives neutrophilic pleocytosis, and HSV affects temporal parenchyma, not basal meninges.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.