NEUROLOGY 01

A 55 year old woman presents with a few months history of progressive cognitive decline, mental slowness, apathy, and urinary incontinence. Her daughter said that her mother's illness started as a bizarre inability to walk although she is able to move her legs fully and actively in bed. She was treated ten years ago for pyogenic meningitis that resolved without any residual symptoms.

What is the most likely diagnosis?


A. Hereditary spinocerebellar ataxia
B. Wilson's disease
C. Normal pressure hydrocephalus
D. Huntington's disease
E. Pseudotumor cerebri


THE ANSWER IS  C. Normal pressure hydrocephalus

Normal pressure hydrocephalus (NPH) is a “stable,” communicating hydrocephus where the intracranial pressure is within normal limits. The exact mechanism for this equilibrium is unknown, but it is thought to be due to impaired cerebrospinal fluid (CSF) reabsorption at the arachnnoid villi. NPH exhibits a classic triad (also called Adam's triad) of urinary incontinence, gait disturbance and dementia. Two easy ways to remember it is "wet, wobbly and wacky" or "weird walking water.”
NPH is often misdiagnosed as either Alzheimer's disease or Parkinson's disease due to its chronic nature and presenting symptoms. It is one of the few reversible dementias; the symptoms are relieved with treatment—the insertion of a ventricular shunt to drain off excess CSF. Although the etiology of most cases is unknown, some patients show a correlation of developing NPH several years after a subarachnoid haemorrhage, head injury, cranial surgery, or CNS infection. Note: pyogenic meningitis is caused by a bacterial infection.
Hereditary spinocerebellar ataxia (choice A) is a genetic disorder with progressive ataxia due to atrophy of the cerebellum. Throughout the illness, patients retain their full mental capacity.
Wilson's disease (choice B) is a multi-organ disorder that affects the kidney, liver, eyes (Kayser-Fleischer rings), heart and endocrine system. Neurologic symptoms include: cognitive deterioration, dystonia, ataxia and changes in behavior.
Huntington's disease (choice D) is a type of subcortical dementia involving the destruction of the caudate nucleus. Patients characteristically present with excessive, unintentional movements of the body called chorea.
Pseudotumor cerebri (choice E) is characterized by increased intracranial pressure, headaches, and papilledema without any demonstrable intracranial lesion. It tends to occur in overweight women from 20 to 50 years of age— also called benign intracranial hypertension.