What is Nasu-Hakola Disease (NHD) or Polycystic Lipomembranous Osteodysplasia with Sclerosing Leukoencephalopathy (PLOSL)?

NHD is a rare inherited leukodystrophy characterized by progressive early dementia associated with recurrent bone fractures and bone cysts.

What Are the Symptoms?

The symptoms of this disorder are usually divided into four stages:

  • Latent
    • Pain in the hands, wrists, ankles and feet – typical onset is 20 to 30 years
  • Osseous
    • Recurrent bone fractures due to polycystic osseous and osteoporotic lesions in the limb bones
  • Early Neurologic
    • Personality changes – euphoria, lack of concentration, loss of judgement and social inhibitions
    • Mild and progressive memory disturbances
    • Epileptic seizures
  • Late Neurologic
    • Profound dementia
    • Unable to speak and move

How Do You Get NHD?

This disorder is caused by mutations in either the TYROBP or TREM2 gene.

How Is NHD Diagnosed?

This disorder is diagnosed through examination of physical symptoms, thorough clinical evaluation, X-ray, MRI and genetic testing.

Is There a Treatment?

There is no known cure. Treatment is symptomatic and may include antiepileptic medication and regular neurological and orthopedic monitoring.

Helpful Resources

orphanet

Wikipedia

Leukodystrophy Care Network