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Background: Myxedema coma (MC), a medical emergency defined as severe hypothyroidism leading to altered mental status, is more common in older women with hypothyroidism., Methods/results: A 7-year-old Caucasian male with chromosome 1q deletion presented with altered mental status preceded by milestone regression. His presenting labs results were: thyroid-stimulating hormone (TSH) 0.501 μIU/ml and free thyroxine (T4) <0.5 ng/dl. His morning cortisol level was 8.1 μg/dl with repeat testing, while TSH was 1.119 μIU/ml and free T4 was 0.5 ng/dl. Low-dose cosyntropin test showed baseline and peak cortisol levels of 1.9 and 16 μg/dl, respectively. Aside from altered mental status, heart block was present in addition to hypothermia and hypercarbia. Diffuse cerebral cortical and corpus callosum atrophy were seen on MRI. An intravenous (i.v.) stress dose of hydrocortisone was administered for 24 h prior to an i.v. loading dose of levothyroxine. His activity level subsequently returned to baseline within 48 h after treatment had been initiated., Conclusion: Though MC is rare, occurring mainly with noncompliance in primary hypothyroidism, it may occur at the diagnosis of secondary hypothyroidism. Based on features like hypothermia, hypoventilation, and cardiovascular instability occurring in the setting of central hypothyroidism, it should be suspected and managed urgently in order to avert the associated high mortality resulting from treatment delays., (© 2016 S. Karger AG, Basel.)

Biomarkers that indicate the severity of hypoxic-ischemic brain injury and response to treatment and that predict neurodevelopmental outcomes are urgently needed to improve the care of affected neonates. We hypothesize that sequentially obtained plasma metabolomes will provide indicators of brain injury and repair, allowing for the prediction of neurodevelopmental outcomes. A total of 33 Macaca nemestrina underwent 0, 15 or 18 min of in utero umbilical cord occlusion (UCO) to induce hypoxic-ischemic encephalopathy and were then delivered by hysterotomy, resuscitated and stabilized. Serial blood samples were obtained at baseline (cord blood) and at 0.1, 24, 48, and 72 h of age. Treatment groups included nonasphyxiated controls (n = 7), untreated UCO (n = 11), UCO + hypothermia (HT; n = 6), and UCO + HT + erythropoietin (n = 9). Metabolites were extracted and analyzed using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry and quantified by PARAFAC (parallel factor analysis). Using nontargeted discovery-based methods, we identified 63 metabolites as potential biomarkers. The changes in metabolite concentrations were characterized and compared between treatment groups. Further comparison determined that 8 metabolites (arachidonic acid, butanoic acid, citric acid, fumaric acid, lactate, malate, propanoic acid, and succinic acid) correlated with early and/or long-term neurodevelopmental outcomes. The combined outcomes of death or cerebral palsy correlated with citric acid, fumaric acid, lactate, and propanoic acid. This change in circulating metabolome after UCO may reflect cellular metabolism and biochemical changes in response to the severity of brain injury and have potential to predict neurodevelopmental outcomes., (© 2015 S. Karger AG, Basel.)

Melatonin, a major photoperiod-dependent hormone, regulates circadian rhythms and biological rhythms and acts as a prominent sleep promoter. Symptoms related to hypermelatoninemia have been reported in individuals supplemented with melatonin. However, spontaneous endogenous hypermelatoninemia has not been reported previously. A 6-year-old girl previously diagnosed with Shapiro's syndrome was admitted to our hospital on several occasions during a 1-year period with complaints of altered consciousness, syncope, hypothermia and episodes of sweating. The episodes occurred daily and during sleep and lasted for 1-6 h. During these episodes, she sweated profusely and felt faint and her skin was pale and cool. Other complaints included recurrent abdominal pain, urge incontinence and myopia. She was shown to have hypermelatoninemia (>1,000 pg/ml, normal range 0-150 pg/ml) during these episodes. The duration of her attacks decreased with phototherapy and she was successfully treated with propranolol. To our knowledge, this is the first case of hypermelatoninemia without any detectable organic pathology. We did not determine the exact mechanism of hypermelatoninemia in this patient; however, it might have been related to irregular control of pinealocytes by the suprachiasmatic nucleus or related pathways. Hypermelatoninemia should be considered in patients with spontaneous periodic hypothermia and hyperhidrosis, and also in patients with Shapiro's syndrome., (Copyright © 2010 S. Karger AG, Basel.)

Episodic spontaneous hypothermia is an infrequent disorder, the pathogenic mechanisms of which have not been completely clarified, although alterations in the serotoninergic system have been suggested. We report the history of a girl with episodes of dizziness and shivering associated with a body temperature lower than 35 degrees C since the age of 10 months. At the age of 11 years, she was admitted to a local hospital and an oral glucose tolerance test showed high total insulin levels. Hypoglycemia secondary to hyperinsulinemia was suspected, and a low-carbohydrate (simple) diet was proposed without results. Due to the recurrence of the episodes, episodic spontaneous hypothermia triggered by hyperinsulinemia was suspected, and treatment with flunarizine, a drug considered the first line in the treatment of migraine-related disorders, was started with a resulting reduction in the episodes. A new endocrinological evaluation showed decreased insulin secretion. In our patient, the success of the therapy might be due to the well-known effect of calcium antagonists in inhibiting serotonin uptake and thereby regulating serotonin levels after hyperinsulinism. This case suggests hyperinsulinemia as a potential mechanism for episodic spontaneous hypothermia, probably mediated by an interaction between insulin and the serotoninergic system., (Copyright 2009 S. Karger AG, Basel.)

The hepatic glucose uptake of male garden lizards did not change during maturation but showed a decline between middle-aged and old age groups. The decline in glucose uptake following starvation and cold stress was age-dependent, the young and middle-aged lizards being more responsive than the old counterparts.

The endocrine reactivity to a short-term cold exposure (+ 4 degrees C during 1 h 30 min) was studied in 8 full-term (FT) and 12 preterm (PT) Limousin x Romanov lambs, obtained by oestrogen injections to the ewes; 4 PT animals died (PTD) during the observation period and 8 remained alive (PTA). The plasma cortisol, T4 and T3 levels were lower in PT lambs (particularly in PTD for T4 and T3) during the first hours of life. Moreover, rectal temperature decreased sharply between birth and 30 min postpartum in the PT group; at this time, plasma T3 levels and rectal temperature were positively related. During cold exposure, the plasma cortisol levels increased in FT lambs, but did not change in the PT group. Moreover, the plasma T4 levels rose slightly in FT animals (+ 12%), increased sharply in PTA lambs (+ 137%), or showed a small decrease in the PTD group (-5%) in which a marked hypothermia occurred; the relative changes in the circulating T4 levels were positively related to the algebraic variations of rectal temperature in PT lambs. However, the changes in the plasma T3 levels did not parallel that of T4 in the three groups of animals, but a positive relationship was observed, in all lambs, between the circulating T3 levels and the rectal temperatures at the end of the cold exposure. These results suggest a reduced sensitivity of the adrenal cortex to stressful conditions in PT lambs. Moreover, they underline the importance of thyroid function for thermoregulation in the newborn lamb, particularly in PT animals.

Blood glucose, blood lactate, plasma free fatty acids, plasma alpha-amino nitrogen, plasma free amino acids and blood urea nitrogen were measured in 15 hypothermic preterm infants (mean rectal temperature: 34.5 +/- 0.28 degrees C) during a 2-hour 'warming-up' period following admission to our neonatal intensive care unit. Hypothermia was associated with lactacidemia and hyperalaninemia. The increase in body temperature of the infants resulted in the decrease of lactacidemia and hyperalaninemia. Normal levels of other metabolites remained unchanged.