Working Diagnosis:
Myoadenylate deaminase deficiency (MADD), an exercise-induced metabolic myopathy
Treatment:
Activity modification with focus on avoiding activities that exacerbated symptoms, with adequate periods of rest in between. Patient's training regimen was decreased, with close supervision from athletic trainers to build tolerance for longer duration of activity without symptoms. Most people with MADD are able to continue playing sports and exercising with the proper activity modifications.
Outcome:
Patient has continued his modified training regimen with hopes to finish football games without having cramping symptoms. He has not returned for follow up at the office.
Editor's Comments:
This is an uncommon diagnosis that presented with a common complaint. Cramping in football players is a common occurrence but rarely is it due to a metabolic disorder. This case demonstrated how the metabolic disorder presented and how it was evaluated and assessed. The fact that genetic testing was utilized instead of a muscle biopsy is interesting as well.
References:
Rannou F, Uguen A, Scotet V, Le Marechal C, Rigal O, Marcorelles P, et al. (2015) Diagnostic Algorithm for Glycogenoses and Myodenylate Deaminase Deficiency Based on Exercise Testing Parameters: A Prospective Study. PLoS One 10(7): e0132972. https://doi.org/10.1371/journal.pone.0132972
Tarnopolsky MA. (2016) Metabolic Myopathies. Muscle and Neuromuscular Junction Disorders 22(6): 1829-51. doi: 10.1212/CON.0000000000000403
Return To The Case Studies List.