Dementia paralytica: deterioration from communicating hydrocephalus

Area of Science:

• Neurology
• Neurosurgery
• Infectious Diseases

Background:

• Dementia paralytica, a late stage of syphilis, typically responds to penicillin treatment.
• Some patients with dementia paralytica show poor response or deterioration despite adequate penicillin therapy.
• Communicating hydrocephalus is a potential, yet under-recognized, complication in neurosyphilis.

Purpose of the Study:

• To investigate the role of communicating hydrocephalus in patients with dementia paralytica refractory to penicillin.
• To evaluate the diagnostic utility of neuroimaging and cerebrospinal fluid (CSF) dynamics in identifying this complication.
• To assess the efficacy of CSF shunting as a treatment for hydrocephalus-induced symptoms in dementia paralytica.

Main Methods:

• Retrospective analysis of five patients with dementia paralytica and poor penicillin response.
• Pneumoencephalography and isotope cisternography to assess CSF flow and ventricular size.
• Clinical assessment of neurological status, including gait, incontinence, and pyramidal signs.
• Evaluation of surgical outcomes following CSF shunting procedures.

Main Results:

• Pneumoencephalography revealed patterns suggestive of communicating hydrocephalus in non-responding patients.
• Isotope cisternography confirmed CSF flow obstruction at the parasagittal subarachnoid space in affected individuals.
• Three patients presented with severe dementia, gait apraxia, incontinence, and pyramidal signs.
• CSF shunting led to immediate and significant improvement in two out of three treated patients.
• Brain biopsies showed leptomeningeal fibrosis but no active parenchymal inflammation.

Conclusions:

• Chronic leptomeningitis in dementia paralytica can lead to impaired CSF absorption and communicating hydrocephalus.
• Refractory or progressive dementia paralytica warrants investigation for associated communicating hydrocephalus.
• CSF shunting can be an effective treatment for hydrocephalus-related neurological deficits in dementia paralytica.