An Unusual Cause for High Creatine Kinase Levels in an Acute Care Setting

Ryanodine receptor 1 (RyR1) group of myopathies are rare disorders with a fairly common initial presentation. A high index of suspicion while evaluating patients being readmitted with similar presentations in the Acute Medical Units (AMU) can aid diagnosis of rare diseases. We report the scenario of a young gentleman who presented to AMU with severe myalgia for one week. His creatine kinase (CK) levels were considerably high. He was further investigated following MDT (Multi-Disciplinary Team) discussion. He was diagnosed with exercise induced rise in CK levels, and discharged. Two months later, he represented to the A&E (Accident & Emergency department) and was admitted to the AMU with the same complaints. Thorough investigations raised the suspicion of a genetic disease and a muscle biopsy was planned. He was referred to specialised neuromuscular services in the country for further evaluation where he was diagnosed to have a RYR1-related myopathy, which is a rare congenital muscle disease, resulting from an alteration in the RYR1 gene.