Lipomembranous polycystic osteodysplasia (brain, bone, and fat disease): a genetic cause of presenile dementia.

Progressive presenile dementia with lipomembranous polycystic osteodysplasia was first described by Jarvi and Hakola in an isolated region of Finland. We report the occurrence of this disorder in 4 of 10 siblings in an American family of Czechoslovakian ancestry. Characteristics of the disease include multiple bone cysts with pathologic fractures, progressive dementia with seizures and abnormal EEG, calcification of basal ganglia, and death in the fourth to six decades. Autosomal-recessive inheritance is likely. Electronmicroscopy of fat cells reveals peculiar membrane convolutions. Limited neuropathologic material has shown gliosis and demyelination of white matter, senile plaques, and neurofibrillary tangles. Leukemia and a disorder of intestinal motility may be associated findings. Prevalence of the disorder is unknown, partly because it may be confused with Alzheimer disease and fibrous dysplasia of bone. Radiographs of hands and feet should be part of the evaluation of patients with unexplained presenile dementia.