- At least 2 of the criteria listed below:
- Symptom triggers: Exercise, fasting, fever and heat
- Variable CK with exacerbations >10x above basal value
- Myoglobinuria (tea or coca cola coloured urine)
- In patient treatment for acute rhabdomyolysis with or without acute renal failure
- Muscle weakness is progressive
- Usually muscle pain associated with atrophy and weakness
- Malignant Hyperpyrexia syndrome
- Neuroleptic Malignant syndrome
- Acute compartment Syndrome
Individuals with severe or syndromic disease should be recruited according to standard guidance, typically as trios. Disease status of apparently unaffected participants should be determined according to standard clinical practice to detect cryptic disease. In other cases, unaffected individuals should not be recruited. Recruitment in such families should favour multiplex families over single isolated cases. These singleton recruits will not contribute to the overall singleton monitoring metrics applied to GMCs.
- Non exercise related limb pain
- Muscle biopsy with histochemical enzyme or sarcolemmal protein deficiencies to indicate a diagnosis of GSDV, GSDVII or muscular dystrophy (Becker or LGMD)
- Abnormal fasting blood acyl carnitines and/or urine organic acids consistent with a known FAODD
- Confirmed viral induced myositis without myoglobinuria
- Prescribed (e.g. statin) or recreational drug triggers
- Severe trauma
Prior genetic testing guidance
- Results should have been reviewed for all genetic tests undertaken, including disease-relevant genes in exome sequencing data. The patient is not eligible if they have a molecular diagnosis for their condition.
- Genetic testing should continue according to routine local practice for this phenotype regardless of recruitment to the project; results of these tests must be submitted via the ‘Genetic investigations’ section of the data capture tool to allow comparison of WGS with current standard testing.
PLEASE NOTE: The sensitivity of WGS compared to current diagnostic genetic testing has not yet been established. It is therefore important that tests which are clinically indicated under local standard practice continue to be carried out.
These requirements will be kept under continual review during the main programme and may be subject to change.