To strengthen the prevention and treatment of postoperative complications of thyrotoxicosis in secondary hyperparathyroidism patients with end-stage renal disease / 中华内分泌外科杂志

Chronic kidney disease,especially in patients with end-stage renal disease (ESRD),is prone to causing secondary hyperparathyroidism,and part of refractory secondary hyperparathyroidism patients require treatment with parathyroidectomy.Parathyroidectomy makes the thyroid inevitably subject to mechanical stimulation,leading to transient mechanical thyroiditis,hyperthyroxinemia and postoperative transient thyrotoxicosis,causing dysfunction in multiple systems of the body,and even inducing or aggravating water and electrolyte disorders (such as hyperkalemia),arrhythmia and cardiovascular events.However,this complication has not yet received sufficient clinical attention.This article will discuss the prevention and treatment of thyrotoxicosis or hyperthyroidism,one of the postoperative complications,in secondary hyperparathyroidism patients with ESRD,based on the relevant documents and our own clinical practice.

Thyroid Stimulating Hormone Level at Diagnosis as a Predictor of Persistent Subclinical Hypothyroidism in Children with Down Syndrome

Objective: To evaluate subclinical hypothyroidism in a cohort of children with Downsyndrome and identify a TSH level at the time of diagnosis to predict persistenthypothyroidism. Methods: 192 children (age <3 years) with Down syndrome, registered intheGenetic Clinic of a referral tertiary care Hospital from 2010 to 2015 were evaluated withthyroid function test at initial visits and subsequently based on standard protocol. Childrenwith subclinical hypothyroidism were evaluated at 3 years of age after discontinuation ofthyroxine for 3 months. Results: 47 (24.5%) children had elevated TSH and among them 43(91.5%) had subclinical hypothyroidism. Among the subclinical hypothyroidism group, 25(73.5%) had transient hypothyroidism and 9 (26.5%) persistent hypothyroidism. Initial TSHlevel at the time of diagnosis was higher in persistent hypothyroidism group as compared totransient group (P= 0.003). The best cut-off level for prediction of persistent hypothyroidismfor initial TSH level was 11.6 mIU/L. Conclusion: Subclinical hypothyroidism, especiallytransient, is the commonest form of thyroid dysfunction in children with Down syndrome. Theinitial TSH level may help to predict the possibility of persistence of hypothyroidism.

First Report of Familial Dysalbuminemic Hyperthyroxinemia With an ALB Variant

Familial dysalbuminemic hyperthyroxinemia (FDH) is an inherited disease characterized by increased circulating total thyroxine (T4) levels and normal physiological thyroid function. Heterozygous albumin gene (ALB) variants have been reported to be the underlying cause of FDH. To our knowledge, there have been no confirmed FDH cases in Korea. We recently observed a female patient with mild T4 elevation (1.2 to 1.4-fold) and variable levels of free T4 according to different assay methods. Upon Sanger sequencing of her ALB, a heterozygous c.725G>A (p.Arg242His) variant was identified. The patient's father and eldest son had similar thyroid function test results and were confirmed to have the same variant. Although the prevalence of FDH might be very low in the Korean population, clinical suspicion is important to avoid unnecessary evaluation and treatment.

Thyroxine binding globulin excess detected by neonatal screening

Inherited thyroxine binding globulin (TBG) disorder can be identified incidentally or through neonatal screening test. TBG excess is characterized by high levels of thyroxine (T4) but normal level of free T4 (fT4), while TBG deficiency presents with low T4 levels and normal fT4 levels. A 27-day-old newborn was brought to the hospital because of hyperthyroxinemia detected by neonatal screening. His T4 level was 18.83 µg/dL (normal range, 5.9-16.0 µg/dL). His mother had no history of any thyroid disease. His fT4 and thyroid stimulating hormone (TSH) levels were 1.99 ng/dL (normal range, 0.8-2.1 ng/dL) and 4.54 mIU/L (normal range, 0.5-6.5 mIU/L), respectively. His serum total triiodothyronine (T3) level was 322.5 ng/dL (normal range, 105.0-245.0 ng/dL). His TBG level was 68.27 mg/L (normal range, 16.0-36.0 mg/L) at the age of 3 months. At 6 months and 12 months of age, his TBG levels were 48.77 mg/L (normal range, 16.0-36.0 mg/L) and 50.20 mg/L (normal range, 14.0-28.0 mg/L), respectively, which were 2 to 3 times higher than normal values. Hormonal studies showed consistently elevated T3 and T4 levels and upper normal levels of fT4 and free T3 with normal TSH levels. His growth and development were normal. TBG excess should be considered as a potential differential diagnosis for hyperthyroxinemia and especially high T3 levels with normal TSH concentration.

Thyroxine binding globulin excess detected by neonatal screening

Inherited thyroxine binding globulin (TBG) disorder can be identified incidentally or through neonatal screening test. TBG excess is characterized by high levels of thyroxine (T4) but normal level of free T4 (fT4), while TBG deficiency presents with low T4 levels and normal fT4 levels. A 27-day-old newborn was brought to the hospital because of hyperthyroxinemia detected by neonatal screening. His T4 level was 18.83 µg/dL (normal range, 5.9-16.0 µg/dL). His mother had no history of any thyroid disease. His fT4 and thyroid stimulating hormone (TSH) levels were 1.99 ng/dL (normal range, 0.8-2.1 ng/dL) and 4.54 mIU/L (normal range, 0.5-6.5 mIU/L), respectively. His serum total triiodothyronine (T3) level was 322.5 ng/dL (normal range, 105.0-245.0 ng/dL). His TBG level was 68.27 mg/L (normal range, 16.0-36.0 mg/L) at the age of 3 months. At 6 months and 12 months of age, his TBG levels were 48.77 mg/L (normal range, 16.0-36.0 mg/L) and 50.20 mg/L (normal range, 14.0-28.0 mg/L), respectively, which were 2 to 3 times higher than normal values. Hormonal studies showed consistently elevated T3 and T4 levels and upper normal levels of fT4 and free T3 with normal TSH levels. His growth and development were normal. TBG excess should be considered as a potential differential diagnosis for hyperthyroxinemia and especially high T3 levels with normal TSH concentration.

Anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia and suspected impairment of T4 to T3 conversion: a case report / 대한마취과학회지

We report an anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia (elevated free thyroxine, fT4 and normal 3, 5, 3'-L-triiodothyronine, T3) and suspected impairment of conversion from T4 to T3. Despite marked hyperthyroxinemia, this patient's perioperative hemodynamic profile was suspected to be the result of hypothyroidism, in reference to the presence of T4 to T3 conversion disorder. We suspected that pretreatment with antithyroid medication before surgery, surgical stress and anesthesia may have contributed to the decreased T3 level after surgery. She was treated with liothyronine sodium (T3) after surgery which restored her hemodynamic profile to normal. Anesthesiologists may be aware of potential risk and caveats of inducing hypothyroidism in patients with euthyroid hyperthyroxinemia and T4 to T3 conversion impairment.

Preoperative preparation for thyroid nodular disease concomitant with hyperthyroxinemia / 中华内分泌外科杂志

Objective To explore the feasibility of individualized preoperative preparation for thyroid nodular disease concomitant with hyperthyroxinemia. Methods According to different clinical manifestations,traditional preoperative medical preparation, impulse preoperative medical preparation and propranolol preoperative medical preparation were respectively made on 43 cases of thyroid nodular disease concomitant with hyperthyroxinemia and without eye proptosis. Preoperative medical preparation wasn't performed on 12 eases of hyperthyroxinemia without apparent hypermetabolism and basal metabolic rate less than 20%. Hospitalization time and incidence of intraoperative and postoperative complication were observed and recorded. Results Intraoperative and postoperative thyroid crisis or serious complications didn't occur in all 43 cases of thyroid nodular disease concomitant with hyperthyroxinemia and without eye proptosis. Hospitalization time differs for patients with different preoperative preparation. Conclusion It was feasible to make individualized preoperative preparation for thyroid nodular disease concomitant with hyperthyroxinemia.