Urinary titin in myotonic dystrophy type 1.

INTRODUCTION/AIMS: Urinary titin, an easy-to-obtain marker, has been investigated in muscular dystrophies, but not in myotonic dystrophy type 1 (DM1). We investigated the role of titin as a biomarker of muscle injury in DM1. METHODS: We compared the urinary titin N-fragment/creatinine ratio in 29 patients with DM1 vs. 30 healthy controls. We also recorded clinical data such as muscle strength, serum creatine kinase, DM1-related outcome measures, and the 20-item DM1-activ questionnaire. The severity of the disease was graded using the Muscular Impairment Rating Scale (MIRS). RESULTS: The titin/creatinine ratio was significantly higher in the urine samples of DM1 patients than of healthy controls (median ± mean absolute deviation [MAD]: 39.313 ± 26.546 vs. 6.768 ± 5.245 pmol/mg creatinine; P < .001), and was related to muscle impairment graded by MIRS (τ = 0.503, P = .038). DISCUSSION: Urinary titin may be a biomarker for DM1. Long-term follow-up of DM1 patients is needed to investigate the potential role of titin as a biomarker for disease activity and progression.

[Risk factors for ischaemic stroke in myotonic dystrophy type 1]. / Az ischaemiás stroke kockázati tényezoi a dystrophia myotonica 1-es típusában.

INTRODUCTION: Myotonic dystrophy is one of the most common autosomal dominant inherited muscular diseases. In both subtypes, not only the musculoskeletal system but other organs are also affected as a result of mis-splicing of several messenger RNAs leading to the production of dysfunctional proteins. Cataract, reduced pulmonary capacity, rhythm disorders, glucose intolerance, dyslipidaemia, endocrinopathies and cognitive impairment are also obtained in patients with myotonic dystrophy. OBJECTIVE: We aimed to assess the risk factors of ischaemic stroke in our patients. METHOD: After a detailed review of the patients' medical history, laboratory and clinical tests and a carotid ultrasound examination were performed. RESULTS: We found atherogenic dyslipidaemia, high risk of cardiogenicembolism, and normal carotid artery intimal media thickness. DISCUSSION: Our result can suggest the role of atrial fibrillation and other supraventricular rhythm disorders as important risk factors for ischemic stroke in patients with myotonic dystrophy. CONCLUSION: During the longitudinal follow-up of the patient population suffering from dystrophia myotonica type 1, special attention must also be paid to cardiology care. Orv Hetil. 2022; 163(49): 1962-1966.