McArdle disease presenting as acute renal failure

Area of Science:

• Biochemistry
• Genetics
• Neurology

Background:

• McArdle disease (glycogen storage disease V [GSDV]) is a metabolic myopathy.
• It stems from a deficiency in the myophosphorylase enzyme, impairing glycogenolysis in muscles.
• Clinical features include exercise intolerance, muscle pain, weakness, and elevated creatine kinase due to rhabdomyolysis.

Observation:

• A novel case of McArdle disease is presented in a patient with co-existing sickle cell trait and bulimia.
• The diagnosis was delayed despite multiple hospital admissions for elevated creatine kinase and myopathy.
• The patient's condition remained unrecognized until presenting with acute renal failure.

Findings:

• This case underscores the diagnostic challenges associated with McArdle disease, particularly in patients with comorbidities.
• The interplay of sickle cell trait and bulimia may have masked or complicated the presentation of GSDV.
• Delayed diagnosis of GSDV can lead to severe complications such as acute renal failure.

Implications:

• Early recognition and diagnosis of McArdle disease are crucial for timely management and prevention of complications.
• Consideration of rare metabolic myopathies like GSDV is important in patients with unexplained myopathy and elevated creatine kinase.
• Further research into the phenotypic variability and potential interactions of GSDV with other conditions is warranted.