Nasu-Hakola Disease

PLOSL is an adult-onset recessively inherited disorder of bones and central nervous system leading to early dementia and death. Recent studies have shown that the genetic basis of PLOSL is mutation(s) in the gene encoding a tyrosine kinase-binding protein TYROBP. Onset of clinical disease occurs in the third decade of life with pain and swelling following strain of the wrist and ankle. Fractures may occur after minor accidents. Neuropsychiatric symptoms begin after age of 30 years presenting progressive dementia with an accentuated prefrontal syndrome, signs of upper motor neuron involvement, agnostic-aparactic-aphasic symptoms, myoclonic jerks and epileptic seizures. Death occurs before the age 50.