Discrepancy between ventricular and lumbar CSF in chronic meningitis

Meningitis patient can present with various manifestation including hydrocephalus due to multiple reason. Diagnosis of meningitis mainly rely on CSF analysis which is usually obtained from lumbar puncture. In case of hydrocephalus CSF can be obtain from ventricles during VP shunt operation. Sometimes ventricular CSF can be normal in meningitis patient while lumbar CSF shows abnormality. Possible mechanisms behind this phenomenon are discussed here. Patients who present with hydrocephalus and have normal Ventricular CSF should investigated with lumbar CSF analysis in a view of delay in diagnosis and treatment.