Infantile-onset spinal muscular atrophy with respiratory distress-1 diagnosed in a 20-year-old man.

Spinal muscular atrophy with respiratory distress (SMARD1) presents within the first 13months of age with low birth weight, progressive length dependent motor neuropathy, and respiratory failure from diaphragmatic paralysis. SMARD1 is caused by mutations in IGHMBP2, encoding the immunoglobulin μ-binding protein 2. Because of the severity of the disorder, many infantile-onset SMARD1 patients do not live past the first decade of life. This report documents the clinical course of a 20-year-old man diagnosed with SMARD1.