Hypotonia, weakness, and pontocerebellar hypoplasia in siblings.

A 6-week-old girl presenting with severe weakness, hypotonia, gastroesophageal reflux, and microcephaly as well as dysmorphic features including micrognathia and high arched palate was also found to have pontocerebellar hypoplasia. She died of acute pneumonia at age 6 months. Her younger brother also had generalized hypotonia, weakness, areflexia, and tongue fasciculations and was also noted to have pontocerebellar hypoplasia revealed by brain magnetic resonance imaging. We herein briefly review familial spinal muscular atrophy with type 1 pontocerebellar hypoplasia in children.