Laforêt, Pascal

Background Rhabdomyolysis is a complex and potentially life-threatening syndrome characterized by the rapid breakdown of damaged skeletal muscle. Despite its clinical significance, universally accepted diagnostic criteria and standardized management guidelines are lacking. Methods A cross-sectional online survey about the current diagnostic approach, assessment of risk factors and severity, and management of follow-up of rhabdomyolysis was conducted among clinicians across Europe, Australia, and the USA. Results Fifty-four respondents from 16 countries completed the survey. Results revealed considerable variability in hospital admission practices, and patient follow-up. Some agreement was found in the frequent use of genetic and neurophysiological testing in as diagnostic tools. The survey revealed no consensus on which CK-level would be considered cut-off levels for rhabdomyolysis. Conclusions The survey found little to no coherent approach to diagnosing, assessment of severity, nor follow-up of rhabdomyolysis among respondents who were primarily neurologists and pediatric neurologists. It highlights the need for international guidelines in the diagnostic process, treatment and follow-up of rhabdomyolysis as well as a universally agreed definition of rhabdomyolysis.

Glycogen storage diseases are important causes of myopathy and cardiomyopathy. We describe 10 patients from 8 families with childhood or juvenile onset of myopathy, 8 of whom also had rapidly progressive cardiomyopathy, requiring heart transplant in 4. The patients were homozygous or compound heterozygous for missense or truncating mutations in RBCK1, which encodes for a ubiquitin ligase, and had extensive polyglucosan accumulation in skeletal muscle and in the heart in cases of cardiomyopathy. We conclude that RBCK1 deficiency is a frequent cause of polyglucosan storage myopathy associated with progressive muscle weakness and cardiomyopathy. Ann Neurol 2013;74:914–919