Endocrine Abstracts

Introduction: Myxedema coma is a rare life-threatening clinical condition in patients with longstanding severe untreated hypothyroidism, in whom adaptive mechanisms fail to maintain homeostasis. Most patients, however, are not comatose, and, although strict criteria have been proposed, it is often difficult to differentiate it from very severe hypothyroidism, lacking only a precipitating event.

Material and methods: We present the clinical picture of 70 consecutive patients with very severe hypothyroidism seen from 2004 to 2018 at our institution in a retrospective study. Personal history, previous treatment, etiology, clinical symptoms and analytical data variables were recorded. Data were analyzed with the Statistical Package for Social Science (SPSS), version 20.0 (SPSS Inc., Chicago, IL). The results are expressed as mean ± standard deviation (SD) and as percentages of individuals. The Chi-squared test was used to detect differences between categorical variables, and the normal distribution of continuous variables was tested by the Kolmogorov-Smirnov test. The study was approved by the Ethics Committee.

Results: Seventy consecutive patients (49 females (70%) and 21 males (30%)) were admitted in our hospital, with ages between 21 and 92 years (mean: 52.8 yeas) without significant differences between both genders. Their mean weight was 71.75 kg and BMI 27.87 kg/m². Regarding pre-treatment TSH levels, the mean value was 104.1 mUI/l (± 34.6), with a range from the minimum of 52.63 mUI/l, to a maximum of 239.53 mUI/l. 78.6% were not previously on replacement therapy. The most frequent etiology was autoimmune disease (64.3%), followed by radioactive iodine treatment (12.8%), amiodarone (11.4%), surgery (5.7%), methimazole (2.8%), radiotherapy (1.4%) and alemtuzumab (1.4%). The most frequent symptoms were asthenia (92.8%) and cold intolerance (78.5%). Weight gain (71.4%), daytime drowsiness (64.2%), constipation (57%), facial edema (42.8%), snoring (22.8%), difficulty to focus (21.4%) and depressive symptoms (17.1%). Cholesterol (273.5±93 mg/dl), c-HDL (65.7±29.7 mg/dl), c-LDL (166.8±60.3 mg/dl), creatinine (1.14±0.4 mg/dl) and CPK (805.7±119.2 U/l) were all above normal limits.

Conclusion: Severe hypothyroidism can present with classic symptoms of fatigue, weight gain, cold intolerance and constipation in addition to biochemical alterations and should be treated aggressively due to symptoms that lead to a severe impaired quality of life, an increased risk of premature atherosclerotic vascular disease and the risk of development of a myxedema coma in case a precipitating event occurs.