Early infantile sensory-motor neuropathy with late onset respiratory distress

Children with spinal muscular atrophy with respiratory distress (SMARD1) usually present within their first year of life, with respiratory failure due to diaphragmatic paralysis and progressive distal limb weakness. We present a child with a confirmed compound heterozygous IGHMBP2 mutation c.[676G>T];[2083A>T] in whom severe sensory-motor neuropathy preceded diaphragmatic paralysis by almost 3 years. Autonomic system involvement with neurogenic bladder and urine retention were found at 3 years. In summary, our patient highlights the broad spectrum of phenotypes observed in SMARD1. Currently, no prediction of phenotype according to genotype is possible, suggesting that yet unknown factors cause the observed phenotypic variation. Even in the absence of obvious diaphragmatic weakness, SMARD1 should be considered in severe infantile onset neuropathies. High throughput techniques, such as next generation sequencing, will possibly offer a useful approach in the heterogeneous group of inherited neuropathies.