Hereditary neuropathy with liability to pressure palsies in infancy

Hereditary neuropathy with liability to pressure palsies is an autosomal-dominant disorder, classically characterized by recurrent mononeuropathies, associated with a deletion at 17p11.2, encompassing the peripheral myelin protein 22 gene. The typical clinical episodes of pressure palsy are usually noted for the first time during the 2nd or 3rd decade of life. We found only few reports in prepubertal children. We report a case of a 7.5-year-old child with muscle weakness and severe hypotonia associated with developmental gross motor delay. We suspect that bilateral peroneal nerve palsies after birth were the first episode of pressure palsy. Nerve conduction studies demonstrated slightly prolonged distal latencies with normal conduction velocity. Typical features of hereditary neuropathy with liability to pressure palsies with recurrent mononeuropathies were found in the father. DNA analysis revealed 1.5-Mb deletion at 17p11.2 in both father and child. To the best of our knowledge, this patient is one of the youngest ever found with this disease.