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Chronic intracranial hypertension with unexplained cerebrospinal fluid pleocytosis

Yaniv Barkana1, Neta Levin, Yochanan Goldhammer

  • 1Department of Neurology, Sheba Medical Center, Tel Hashomer, Tel Aviv, Israel. idityaniv@yahoo.com

Journal of Neuro-Ophthalmology : the Official Journal of the North American Neuro-Ophthalmology Society
|June 5, 2004
PubMed

Insights

Idiopathic intracranial hypertension (IIH) can present with cerebrospinal fluid pleocytosis, mimicking chronic meningitis. This condition, characterized by elevated intracranial pressure, often responds to standard IIH treatments.

Area of Science:

  • Neurology
  • Neuroscience
  • Ophthalmology

Background:

  • Idiopathic intracranial hypertension (IIH) is a neurological disorder characterized by elevated intracranial pressure without a clear cause.
  • Typical IIH presentation excludes cerebrospinal fluid (CSF) abnormalities like pleocytosis.
  • Chronic meningitis can present with elevated intracranial pressure and CSF pleocytosis.

Purpose of the Study:

  • To identify and characterize patients with IIH exhibiting cerebrospinal fluid (CSF) pleocytosis.
  • To investigate the clinical course, diagnostic challenges, and treatment outcomes in these atypical IIH cases.
  • To determine if IIH treatment protocols are effective for patients presenting with both elevated intracranial pressure and CSF pleocytosis.

Main Methods:

  • Retrospective review of patients diagnosed with idiopathic intracranial hypertension (IIH) over a nine-year period across two academic neurology departments.
  • Inclusion criteria focused on patients with IIH-like symptoms but also cerebrospinal fluid (CSF) pleocytosis.
  • Comprehensive laboratory and neuroimaging evaluations were performed to exclude other causes.

Main Results:

  • Six patients (five female, one male; mean age 25.7 years) presented with IIH symptoms and CSF pleocytosis, predominantly lymphocytes.
  • All patients were obese; no other risk factors for IIH were identified.
  • Medical management for elevated intracranial pressure was effective in five patients; one required shunting. Ophthalmic symptoms resolved or stabilized.

Conclusions:

  • A subset of patients may present with idiopathic chronic meningitis and elevated intracranial pressure.
  • This condition appears to respond favorably to treatments typically used for idiopathic intracranial hypertension (IIH).
  • Recognition of this IIH variant is crucial for appropriate diagnosis and management, preventing unnecessary investigations for chronic meningitis.

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