Endocrine Abstracts

Introduction: Steinert’s myotonic dystrophy (SMD) is a neuromuscular disorder with a multisystem distribution. It is a genetic disease with autosomal dominant transmission. It may be associated with various endocrine disorders.

Observation: We report the case of a 47-year-old patient followed for DM since the age of 18, diabetic under insulin therapy for 20 years, hypertensive for 1 year under losartan 50 mg/d who was referred to us for evaluation of the endocrine impact of his disease. On examination, the patient reported significant asthenia, polyuropolydipsic disorder with 5 nocturnal awakenings, erectile dysfunction, decreased libido and weight gain. Examination: conscious patient, with significant psychomotor slowing down, bilateral congenital ptosis, overweight (BMI = 26.2 kg/m2), normocardial at 91bpm, his blood pressure was 148/72 mmHg, areas of lipodystrophy on the left arm, his thyroid was not palpable. External genitalia examination was normal, her osteotendinous reflexes were weak. On biology, the HbA1c was 12.60%, the thyroid balance: TSH: 1.32 mIU /l T4 21.2pmol/l, the testosteronemia was 4.96 mg/l with gonadotropins: FSH at 4.5 ui /l and LH at 6.7ui /l and a normal prolactinemia, the lipid balance objectified a total hypercholesterolemia at 2.98g/l. The management was based on the reinforcement of the hygienic-dietary rules, the intensification of the insulin therapy and the setting on atorvastatin. The evolution was favorable.

Discussion: Steinert’s myotonic dystrophy is the most common muscular dystrophy in adults [1]. It is an autosomal dominant inherited neuromuscular disorder characterized by myotonia and progressive muscle atrophy. It is multisystemic and highly variable in clinical expression [2]. The endocrine abnormalities most commonly associated with DSM are dysthyroidism, diabetes, peripheral gonadal insufficiency, increased risk of hyperlipidemia, nonalcoholic fatty liver disease, erectile dysfunction, benign and malignant thyroid nodules, bone fractures, miscarriage, premature delivery, and labor failure during delivery. Circulating levels of parathyroid hormone and corticotropic hormone may be elevated, but the mechanisms of these associations are unclear [3-4]. DM is responsible in our patient for poorly controlled diabetes and total hypercholesterolemia. The thyroid workup ruled out hypothyroidism despite the suggestive clinical signs, hypogonadism was also ruled out.

Conclusion: DM does not only concern the neurologist, but requires a multidisciplinary management in which the endocrinologist finds his place both in the screening and in the management. A systematic search for endocrinopathies could help prevent certain complications.