Intrafamilial Variability in LPIN1-Related Rhabdomyolysis

Abstract

LPIN1 molecular alterations were identified as a major cause of severe recurrent rhabdomyolysis. The prognosis is poor, with a third of patients dying from cardiac arrest during an acute episode. We describe herein a familial case of a young boy and his mother both affected by the same homozygous LPIN1 mutation. The index case experienced a first extremely severe episode of rhabdomyolysis at 14 months of age (creatine kinase 630,000 UI/L) and a second, lethal episode at 3 years of age. His mother had only 1 moderate episode of rhabdomyolysis (creatine kinase 3,050 UI/L) in adulthood. Several cases of sudden death were also reported in the family. To the best of our knowledge, the mother of the index case is, to date, the first patient described harbouring biallelic mutations in LPIN1 and only presenting with a mild phenotype. This report expands the phenotypic spectrum of LPIN1-related rhabdomyolysis, illustrating high intrafamilial variability.