A new familial disorder of combined lower motor neuron degeneration and skeletal disorganization.

A new familial disorder, inherited as an autosomal dominant trait and characterized by dual features of neurologic degeneration and skeletal disorganization, is reported. The neurologic disease is a degenerative process of lower motor neurons and develops in middle age with progressive muscle weakness and ends in respiratory failure and premature death. Clinical examination, electromyography, and muscle biopsy with histochemical stains are diagnostic. The skeletal disorganization resembles Paget's disease of bone. It is characterized by polyostotic radiographic abnormalities, elevated serum alkaline phosphatase of bone origin, abnormal radioisotopic bone scan, elevated hydroxyprolinuria, and bone histology.