Marathoning with myotonic dystrophy type 2 (proximal myotonic myopathy) and leukopenia

Abstract

Objectives:A mild, slowly progressive course of proximal myotonic myopathy, also known as myotonic dystrophy type 2, over years allowing the patient to continue with extreme sport activity, has been only rarely reported.Methods:Case report.Results:The patient is a 54-year-old female sport teacher who developed myotonia of the distal upper limbs at the age of 32 years. Over the following 22 years, myotonia spreaded to the entire musculature. Myotonia did not prevent her from doing her job and from marathoning and improved with continuous exercise. Additionally, she had developed hypothyroidism, ovarial cysts, incipient cataract, motor neuropathy, hepatopathy, leukopenia, and mild hyper-CK-emia. A heterozygous CCTG-repeat expansion of 500–9500 was found in the CNBP/ZNF9 gene. At the age of 54 years, she was still performing sport, without presenting with myotonia on clinical examination or having developed other typical manifestations of proximal myotonic myopathy.Conclusions:This case shows that proximal myotonic myopathy may take a mild course over at least 22 years, that proximal myotonic myopathy with mild myotonia may allow a patient to continue strenuous sport activity, and that continuous physical activity may contribute to the mild course of the disease.

Effect of exercise training on functional capacity and body composition in myotonic dystrophy type 2 patients

“…Patients with DM2 are usually ambulatory. A recent case report presented a female DM2 patient who continued regular aerobic exercise managing to run a marathon and self‐reporting a lessening of myotonic symptoms due to exercise training 14 . Therefore, it is hypothesized that exercise training, including both aerobic and resistance training, may provide an adequate stimulus for neuromuscular and cardiovascular adaptations, resulting in significant increases in the functional capacity of DM2 patients.…”