A case of hypokalemic myopathy associated with transient hypothyroidism

A case of transient hypothyroidism in the course of hypokalemic myopathy is reported. A 69-year-old woman had severe muscle weakness and marked potassium deficiency associated with alkalosis during treatment with thiazide diuretics. The cause of muscle weakness proved to be hypokalemic myopathy confirmed by clinical findings and muscle biopsy. After the episode of hypokalemic myopathy, serum levels of thyroid hormone were lowered (T4; 3.8 micrograms/dl, T3; 54 ng/dl) and that of TSH was elevated (25.1 microU/ml). Antithyroid microsomal antibody was positive (1:25600) and anti-thyroglobulin antibody was negative. About one month after potassium supplement, her thyroid functions returned to normal, along with normalization of serum potassium level. This is the first documented case report of hypokalemic myopathy accompanied by transient hypothyroidism in a patient with autoimmune thyroiditis. We suggest that this transient hypothyroidism might be induced by hypokalemia during the course of autoimmune thyroiditis.     

Thyrotoxic Periodic Paralysis and Complicated Thyrotoxicosis,Two Presentations of Hyperthyroidism with Notable Differences in their Clinical Manifestations: An Experience from a Tertiary Care Hospital in the United States

Objective: Thyrotoxic periodic paralysis (TPP) is a muscular disorder characterized by sudden episodes of muscle weakness and hypokalemia in the setting of thyrotoxicosis. We aimed to report our experience with TPP in West Texas and compare its clinical presentation to that of patients admitted for complicated thyrotoxicosis.Methods: Retrospective review of records of adult patients with admission diagnosis of hyperthyroidism, thyrotoxicosis, and/or discharge diagnosis of periodic paralysis seen at our institution in a 6-year period.Results: Patients admitted for complicated thyrotoxicosis were more commonly females of a mean age of 44 years. Patients with TPP were more commonly Hispanic males of a mean age of 27 years. Despite no significantly different thyroid hormone levels, patients with TPP presented with less-severe signs and symptoms of hyperthyroidism, as reflected by lower Burch-Wartofsky score on admission (19 vs. 35; P<.001) and lower occurrence of atrial fibrillation in the TPP group (0% vs. 36%; P<.001). Finally, 89% of TPP patients presented with corrected QT (QTc) prolongation, whereas only 19% of thyrotoxic patient presented with a prolonged QTc.Conclusion: Hispanic patients with TTP seems to have relative resistance to the actions of thyroid hormones and commonly present with QTc prolongation, a risk factor for cardiac arrhythmias.Abbreviations: BWS = Burch-Wartofsky point scale; EKG = electrocardiogram; FT3 = free triiodothyronine; FT4 = free thyroxine; ICD = International Classification of Diseases; QTc = corrected QT; TPP = thyrotoxic periodic paralysis     

Neuroprotective activities of bacopa,lycopene, astaxanthin, and vitamin B12 combination on oxidative stress-dependent neuronal death

Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H₂O₂ in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H₂O₂ cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases.     

Sensitivity of transketolase to the thiamin status of juvenile marine shrimp (Penaeus monodon)

Muscle, hemolymph and hepatopancreas transketolase activities and their thiamin pyrophosphate (TPP) effects were assessed for their potential to determine the thiamin status of juvenile Penaeus monodon after a 9-week feeding trial. Transketolase activity increased in response to increasing thiamin supplementation, while TPP effects decreased with increasing dietary thiamin levels. The TPP effect showed a significant increment when the dietary thiamin was reduced from 20 mg/kg diet to no supplement. Thiamin requirement assessed by TPP effect as the criterion was lower than that by transketolase activity; the thiamin requirement estimated by the TPP effect of the muscle (13.3 mg/kg) and hemolymph (18.3 mg/kg) was similar to that of the growth results (12.9 mg/km). These data suggest that, like vertebrates, measurement of the TPP effect in the tissues of the marine crustacean is a more sensitive indicator of thiamin status than measurement of transketolase activity. Among all criteria examined, the hemolymph TPP effect was the most sensitive and specific indicator of thiamin status.     

Development of Thyroid Storm After Surgical Resection of A Thyrotropin-Secreting Pituitary Adenoma

ObjectiveTo describe a patient with a thyrotropinsecreting pituitary adenoma in whom postoperative thyroid storm developed.MethodsWe present a case report with details of the initial presentation, laboratory evaluation, surgical and pathologic findings, and subsequent course in a patient with a thyrotropin (thyroid-stimulating hormone or TSH)- secreting adenoma and postoperative thyroid storm.ResultsAn 18-year-old male patient presented with severe headaches and was found to have a large suprasellar tumor and a mildly elevated level of TSH. Thyroid storm developed immediately after surgical resection of the pituitary mass. Results of laboratory evaluation undertaken preoperatively became available after the patient had undergone the surgical procedure and revealed thyroid hormone levels 2 to 3 times the upper limit of normal. Propylthiouracil and β-adrenergic blocking agents controlled the postoperative thyrotoxicosis and were subsequently discontinued as his TSH and thyroid hormone levels normalized.ConclusionThis case demonstrates the rare case of a TSH-secreting adenoma in a young patient, which was complicated by the development of postoperative thyroid storm. In addition, this case emphasizes the importance of preoperative pituitary hormonal evaluation and treatment of hormonal abnormalities in all patients presenting with sellar or suprasellar tumors. (Endocr Pract. 2008;14:732- 737)     

Adverse Event Reporting in Patients Treated With Levothyroxine: Results of the Pharmacovigilance Task Force Survey of the American Thyroid Association,American Association of Clinical Endocrinologists,and The Endocrine Society

ObjectiveTo survey physicians to determine whether potency and consistency issues with levothyroxine sodium (LT₄) have been resolved and to assess current experience regarding safety of substituting LT₄ products.MethodsMembers of the American Association of Clinical Endocrinologists, American Thyroid Association, and The Endocrine Society collaborated to create a survey instrument that would effectively sample the clinical experience of their society members and frequent prescribers of LT₄. More than 18 000 e-mailed requests for information were generated, and the Web sites of each society provided links to the data collection form. The survey provided an opportunity to collect clinical observations of adverse events or product availability problems from physicians caring for patients with thyroid disease who required use of contemporary LT₄ preparations.ResultsAfter adjustment for known reasons for unstable results from thyroid function tests, 199 reports of adverse events associated with changes in thyrotropin values were further analyzed. One hundred seventy-seven reports (88.9%) were associated with a change in the source of LT₄; no change was noted in 21(10.6%). Details regarding the circumstances of the change were provided in 167 of the 177 reports (94.4%), The reporting physicians themselves or their office staff had changed the LT₄ preparation in only 1 of the 167 cases (0.6%). The remainder of changes had been made by the patient’s pharmacy, either with the physician’s knowledge (in 13 of 167 cases [7.8%]) or without his/her knowledge (in 153 of 167 cases [91.6%]). Fifty-four of 199 cases (27.1%) described serious adverse events; 52 of these (96.3%) were associated with a substitution of one LT₄ preparation for another.ConclusionsThe clinical use of contemporary LT₄ products continues to be associated with some adverse outcomes. A small number of reports were associated with continued use of the same LT₄ products. The most frequently reported adverse outcomes were associated with the approved generic substitution of LT₄ products, frequently without the prescribing physician’s knowledge.(Endocr Pract. 2010;16:357-370)     

Rhabdomyolysis after Withdrawal of Thyroid Hormone in a Patient with Papillary Thyroid Cancer

ObjectiveTo report a case of rhabdomyolysis presenting with severe hyperkalemia after withdrawal of thyroid hormone in a patient with differentiated thyroid cancer.MethodsWe describe the clinical and laboratory findings of the study patient and review the relevant literature.ResultsA 54-year-old man with progressive generalized weakness and myalgias presented with acute renal failure and hyperkalemia. He had undergone total thyroidectomy for papillary thyroid cancer 6 weeks earlier and had discontinued thyroid hormone 2 weeks before his current presentation in preparation for thyroid remnant ablation. He had a history of multiple colon and small-bowel resections for familial adenomatous polyposis and desmoid tumor. He was severely dehydrated on examination. Laboratory tests results included the following values: creatine phosphokinase, 5265 U/L (reference range, 52-336 U/L); creatinine, 2.1 mg/dL; potassium, > 8.0 mEq/L; and thyrotropin, 92.2 mIU/L. His condition was diagnosed as rhabdomyolysis, and his fluid deficit and hyperkalemia were treated aggressively. Cardiac status remained stable, and both acute renal failure and hyperkalemia improved. He then received remnant ablation, and thyroid hormone was restarted. His muscle complaints resolved over the following 3 months.ConclusionsHypothyroidism-induced rhabdomyolysis can occur during thyroid hormone withdrawal and can present with life-threatening hyperkalemia. Patients undergoing thyroid hormone withdrawal should be assessed for risk of rhabdomyolysis, and preventive strategies should be implemented, including prevention of dehydration.The use of recombinant thyrotropin, rather than thyroid hormone withdrawal, should be considered in those who are at high risk for such complications. (Endocr Pract. 2008;14:1023-1026)     

Renal Function and Plasma Renin activity as Potential Factors Causing Hyperkalemia in Patients with Thyroid Carcinoma Undergoing Thyroid Hormone Withdrawal For Radioactive Iodine Therapy

Objective: Hypothyroidism is not commonly considered a cause of hyperkalemia. We previously reported that hyperkalemia was observed mainly in elderly patients treated with renin-angiotensin-aldosterone system (RAS) inhibitors when levothyroxine treatment was withdrawn for the thyroidectomized patients with thyroid carcinoma to undergo radioactive iodine treatment. Here, we investigated whether acute hypothyroidism causes hyperkalemia in patients who were not treated with RAS inhibitors. We also investigated factors influencing potassium metabolism in hypothyroid patients.Methods: We conducted a single-center, prospective cohort study of 46 Japanese patients with thyroid carcinoma undergoing levothyroxine withdrawal prior to radioiodine therapy. All patients were normokalemic before levothyroxine withdrawal. Blood samples were analyzed 3 times: before, and at 3 and 4 weeks after levothyroxine withdrawal. We investigated factors that may be associated with the elevation of serum potassium levels from a euthyroid state to a hypothyroid state.Results: None of the patients developed symptomatic hyperkalemia. The mean serum potassium level was significantly higher at 4 weeks after levothyroxine withdrawal compared to baseline. The serum sodium levels, the estimated glomerular filtration rate (eGFR), and the plasma renin activity (PRA) decreased significantly as hypothyroidism advanced. In contrast, the plasma levels of adrenocorticotropic hormone, cortisol, aldosterone, and antidiuretic hormone were not changed, while serum thyroid hormone decreased. At 4 weeks after their levothyroxine withdrawal, the patients' serum potassium values were significantly correlated with the eGFR and the PRA.Conclusion: Acute hypothyroidism can cause a significant increase in the serum potassium level, which may be associated with a decreased eGFR and decreased circulating RAS.Abbreviations: ACTH = adrenocorticotropic hormone; ADH = antidiuretic hormone; ATPase = adenosine triphosphatase; eGFR = estimated glomerular filtration rate; HbA1c = glycated hemoglobin; K⁺ = potassium; Na⁺ = sodium; PRA = plasma renin activity; RAS = renin-angiotensin-aldosterone system; T4 = thyroxine; TSH = thyroid-stimulating hormone     

Surgical Utility of Afirma: Effects of High Cancer Prevalence and Oncocytic Cell Types in Patients with Indeterminate Thyroid Cytology

ObjectiveThe Afirma Gene Expression Classifier (GEC) molecular marker assay was developed for the purpose of improving surgical decision-making with indeterminate fine-needle aspiration (FNA) biopsies of thyroid nodules. In this paper, we analyze the performance of the GEC over 27 months in a community hospital-based thyroid surgery practice.MethodsWe began using GEC and Thyroid Cytopathology Partners (TCP) exclusively for thyroid FNA analysis in January 2011, shortly after the Afirma GEC became commercially available. In this paper, we focus on patients with indeterminate FNA results and the outcomes of GEC analysis, with particular attention paid to the calculation of the negative predictive value (NPV) of the Afirma test.ResultsWe performed 645 FNAs in 519 patients over 27 months. Overall, 58 FNAs (9%) were read as indeterminate, with 36 of these classified as suspicious by GEC (62%), 20 characterized as GEC benign (34%), and 2 determined to be inadequate due to low mRNA content. Of the 36 suspicious GEC patients, 30 underwent thyroidectomy, and 21 of the 30 had malignant final pathology. Of the 20 benign GEC patients, 5 underwent thyroid surgery, and 2 were discovered to have malignancies. The NPV for the Afirma GEC in our practice environment was 89.6%.ConclusionIn a practice with a high incidence of thyroid cancer in patients with indeterminate FNAs (33% for our practice), the NPV of the Afirma GEC test may not be as robust as suggested in the existing literature. (Endocr Pract. 2014;20:364-369)     

What if Many Follicular Variant Papillary Thyroid Carcinomas are not Malignant? a Review of Follicular Variant Papillary Thyroid Carcinoma and a Proposal for a New Classification

ObjectivesTo review the relevant literature concerning follicular variant of papillary thyroid carcinoma (FVPTC) with an emphasis on the heterogeneity of this disorder and to propose a new classification for FVPTC on the basis of molecular diagnostics and apply the classification to a typical case.MethodsEnglish-language articles pertaining to FVPTC published between January 1990 and December 2010 were reviewed.ResultsFVPTC is particularly vexing. The criteria for diagnosing FVPTC appear to have changed over the years. Pathologists often disagree about the diagnosis of FVPTC. The clinical behavior of these tumors is variable. Molecular diagnostic studies suggest that FVPTC represents a heterogeneous group of disorders rather than a single entity.ConclusionsOn the basis of the available data, it is proposed that individual cases of FVPTC be reclassified as papillary thyroid carcinoma, follicular thyroid carcinoma, or follicular adenomas, after appropriate molecularbiologic studies have been completed. Long-term followup studies to validate this classification are necessary. (Endocr Pract. 2011;17:768-787)     

Performance of guinea fowl fed hevea seed meal or cashew nut meal as a partial substitute for soya bean meal

Guinea fowl production is increasing in developing countries and has a crucial role in the fight against poverty. However, the feed cost is very high, especially the soya bean meal cost, and farmers cannot afford to buy commercial feed. Consequently, animals do not receive feed adapted to their nutritional needs and they exhibit poor performance. The aim of this paper is to partially substitute soya bean meal by local by-products, discarded, in abundant supply and not used in human nutrition. French Galor guinea fowl (Numida meleagris) and local African guinea fowl (150 birds per breed) were reared for 16 weeks and fed the same starter diet for the initial 4 weeks. From 4 weeks of age, experimental birds from each breed were randomly assigned to three grower isoproteic and isolipidic dietary treatments, each containing five replications (floor pens); each replication included 10 birds of the same breed. The guinea fowl of each breed were fed either control grower diet using soya bean meal as the protein supplement GS, or trial grower diet GN (soya bean meal supplement partially substituted by 15% cashew nut (Anacardium occidentale) meal) or trial grower diet GH (soya bean meal supplement partially substituted by 15% hevea seed (Hevea brasiliensis) meal). The results indicated that hevea seed meal contained a high content of n-3 polyunsaturated fatty acids (PUFAs) (21.2% of total fatty acids (FAs)). The use of hevea seed meal in guinea fowl grower diet was found to exert no adverse effect on growth performance and carcass yield. However, the use of cashew nut meal led to negative effects on performance like daily weight gain and feed conversion ratio. Therefore, cashew nut meal cannot be considered as a suitable partial substitute for soya bean meal in diets. The use of hevea seed meal led to a very low abdominal fat proportion and low blood triglyceride and cholesterol content. Additionally, inclusion of dietary hevea seed meal resulted in guinea fowl meat enriched in PUFAs, especially n-3 FAs, thereby significantly improving the nutritional value.     

Resveratrol Inhibits Sodium/Iodide Symporter Gene Expression and Function in Rat Thyroid Cells

Resveratrol is a polyphenol found in grapes and berries that has antioxidant, antiproliferative and anti-inflammatory properties. For these reasons, it is available as a dietary supplement, and it is under investigation in several clinical trials. Few data are available regarding the effects of resveratrol on thyroid function. A previous study showed that resveratrol transiently increases iodide influx in FRTL-5 rat thyroid cells. Indeed, this increase arises after short treatment times (6–12 h), and no further effects are seen after 24 h. The aim of the present study was to investigate the effects of resveratrol on iodide uptake and sodium/iodide symporter expression in thyroid cells after longer times of treatment. For this purpose, the effects of resveratrol were evaluated both in vitro and in vivo using the rat thyroid FRTL-5 cell line and Sprague-Dawley rats, respectively. In FRTL-5 cells, resveratrol decreased the sodium/iodide symporter RNA and protein expression as a function of time. Furthermore, resveratrol decreased cellular iodide uptake after 48 h of treatment. The inhibitory effect of resveratrol on iodide uptake was confirmed in vivo in Sprague-Dawley rats. This study demonstrates that with longer-term treatment, resveratrol is an inhibitor of sodium/iodide symporter gene expression and function in the thyroid. These data suggest that resveratrol can act as a thyroid disruptor, which indicates the need for caution as a supplement and in therapeutic use.     

Tyrosine Kinase Inhibitors and the Thyroid as Both an Unintended and an Intended Target

ObjectiveTo review the association of the tyrosine kinase inhibitor sunitinib with hypothyroidism as well as the mean time to onset, possible mechanisms, reversibility, and mean duration.MethodsWe performed a MEDLINE search of the English-language literature using a combination of words (“sunitinib,” “tyrosine kinase inhibitors,” “thyroid,” and “hypothyroidism”) to identify original studies and reviews on sunitinib and thyroid function.ResultsHypothyroidism was reported in 36% to 46% of patients who took sunitinib in prospective studies. A higher incidence (53% to 85%) was reported in studies containing both retrospective and prospective data. The mean time to onset of hypothyroidism after initiation of sunitinib therapy ranged from 12 to 50 weeks. The risk of development of hypothyroidism appears to increase with the increasing duration of sunitinib therapy, and the condition is likely reversible once therapy has been discontinued.ConclusionBaseline thyroid function tests should be performed before the initiation of sunitinib treatment. Because hypothyroidism can develop early in the course of therapy, thyroid function tests should be monitored frequently throughout the duration of treatment. Possible mechanisms for thyroid dysfunction include impaired thyroid hormone synthesis, a destructive thyroiditis preceding the development of hypothyroidism, and increased thyroid hormone clearance. If hypothyroidism is identified, levothyroxine therapy should be promptly initiated. (Endocr Pract. 2008;14:618-624)     

Evaluation Of Various Doses Of Recombinant Human Thyrotropin In Patients With Multinodular Goiters

ObjectiveTo assess the safety, adverse effects, and radioactive iodine uptake (RAIU) of recombinant human thyrotropin (rhTSH) using a range of doses in patients with multinodular goiters.MethodsIn this open-label study conducted between June 2002 and December 2004, euthyroid patients with small nontoxic multinodular goiters and normal thyrotropin concentrations were recruited from 4 sites in the United States. Baseline assessments included thyroid function tests, electrocardiogram, Holter monitoring, hyperthyroid symptom scale, flow-volume loop, and measurement of thyroglobulin and thyroperoxidase antibodies. Patients had a baseline 24-hour scan and thyroid iodine I 123 (¹²³I) uptake evaluated at 6, 24, and 48 hours after rhTSH administration. Each patient received a single intramuscular injection of 0.03-mg, 0.1-mg, or 0.3-mg rhTSH followed 24 hours later by 400 μCi ¹²³I orally. Iodine 123 uptakes were again measured 6, 24, and 48 hours later, and a scintigram scan was performed at 24 hours. Thyroid function tests, flow-volume loop, Holter monitoring and/or electrocardiograms, and thyroid ultrasonography to assess thyroid size were performed serially.ResultsTwenty-eight patients participated. Median goiter size was 20 mL (range, 7-79 mL). After each rhTSH dose, the radioiodine uptake approximately doubled at each time point compared with baseline uptake. Small rises in serum thyroxine and triiodothyronine were seen in some patients, especially after 0.3-mg rhTSH, and mild symptoms of hyperthyroidism developed in several patients. Flow-volume loop showed transient, mild asymptomatic worsening in 1 patient with a 35.2 mL goiter, although thyroid volume measurements were unchanged. Minor electrocardiogram and/or Holter changes were seen in several patients.ConclusionsA flat dose-response curve exists over the range of rhTSH doses tested, with an approximate doubling of thyroid RAIU. All patients tolerated rhTSH well, but the rise in thyroid hormone levels and adverse effects after rhTSH doses of 0.1 mg or higher theoretically might not be well tolerated in older or sicker patients and appear unjustified given the lack of a greater rise in RAIU compared with the 0.03-mg dose. Future studies evaluating rhTSH doses less than 0.1 mg in patients with multinodular goiter are justified. (Endocr Pract. 2008;14:832-839)     

Risk-Adapted Management of Thyroid Cancer

ObjectiveTo describe a risk-adapted management paradigm for patients with differentiated thyroid cancer.MethodsA risk-stratification approach is described that combines the standard clinical factors available during the initial evaluation with response-to-therapy variables to predict risk of death from thyroid cancer, risk of recurrence, and risk of failing initial therapy. This classic oncologic approach views risk stratification as an active, ongoing process in which risks are adjusted on the basis of accumulated clinical data, rather than considered as a static initial assessment that does not change.ResultsFrom a clinical standpoint, accurate realtime assessment of risk can be used to guide both the initial treatment recommendations (extent of thyroid surgical resection, role of radioiodine ablation, and degree of thyrotropin suppression) and the follow-up management paradigm (intensity of testing and modalities used to detect recurrent disease).ConclusionBy thinking like oncologists and individualizing therapy on the basis of initial and ongoing risk assessments, we can maximize the beneficial effects of aggressive therapy in patients with thyroid cancer who are likely to benefit from it, while minimizing potential complications and side effects in low-risk patients destined to have a full healthy productive life after minimal therapeutic intervention. (Endocr Pract. 2008;14:764-774)     

Hyalinizing trabecular tumor in a background of lymphocytic thyroiditis: a challenging neoplasm of the thyroid

ObjectiveTo describe a case of hyalinizing trabecular tumor (HTT) in a background of lymphocytic thyroiditis that was misdiagnosed as papillary thyroid carcinoma (PTC) based on fine-needle aspiration (FNA) cytologic findings and overtreated with total thyroidectomy.MethodsWe present a case report, including the imaging and pathologic findings, of a 68-year-old woman who presented with a multinodular goiter that was suspicious for PTC.ResultsOn the basis of FNA cytologic findings, she underwent a total thyroidectomy, and histologic examination of the thyroid gland revealed HTT in a background of lymphocytic thyroiditis. Radioiodine treatment was not administered because of the tumor’s low risk profile. No metastatic foci were established under nonsuppressive levothyroxine therapy after 3 years of follow-up.ConclusionsHTT is a challenging entity because of the uncertainty of its nature, the diagnostic challenges,and the mimicry of other types of thyroid tumors. In order to avoid overtreatment, endocrinologists and thyroid surgeons should be aware of the features of HTT, and suspicious cases should be evaluated by experienced cytopathologists. (Endocr Pract. 2011;17:e140-e143)     

Thyroid Dysfunction,Recovery, and Prognosis in Melanoma Patients Treated with Immune Checkpoint Inhibitors: A Retrospective Review

Objective: To describe thyroid dysfunction, factors associated with thyroid recovery, and survival in melanoma patients treated with immune checkpoint inhibitors that developed thyroid immune-related adverse events (irAEs).Methods: This was a retrospective study in a tertiary center from 2010–2017. We reviewed the charts of patients with melanoma that developed thyroid dysfunction after checkpoint inhibitor therapy. Cases with thyroid irAEs were grouped by recovery of thyroid function at 1 year. We collected a timeline of thyroid function tests, medication exposure, and survival and compared variables between the groups. We studied survival in comparison to a matched group without thyroid dysfunction.Results: A total of 186 melanoma patients received checkpoint inhibitors, and 17 (9%) had thyroid irAEs. Median time to abnormal thyroid-stimulating hormone was 38 days and followed a pattern of thyroiditis. Seven of 17 had thyroid recovery. In the no-recovery group, free thyroxine (T4) was often above 2 ng/dL (5/10 in no recovery, 0/7 in recovery; P = .04). In the recovery group, irAE grade was significantly lower, with 7/7 grade 1 (P = .004). Exposure to glucocorticoids was associated with recovery (3/10 in no recovery, 6/7 in recovery; P = .049). There was no difference in overall survival between the thyroid dysfunction group and controls, or between those that received glucocorticoids or not.Conclusion: Certain aspects of thyroid irAEs may correlate with thyroid recovery, including grade 1 thyroid irAEs, exposure to glucocorticoids, and peak free T4 levels less than 2 ng/dL. Thyroid irAEs did not appear to be associated with change in survival nor did exposure to glucocorticoids.Abbreviations: ASCO = American Society of Clinical Oncology; CTLA-4 = cytotoxic T-lymphocyte–associated protein 4; irAE = immune-related adverse event; PD-1 = programmed cell death protein 1; T4 = thyroxine; TSH = thyroid-stimulating hormone     

Incidental Finding of Metastatic Papillary Thyroid Carcinoma in a Patient with Primary Hyperparathyroidism

ObjectiveTo report on the management of a patient with the rare concurrence of primary hyperparathyroidism and incidentally found metastatic papillary thyroid carcinoma in an adjacent lymph node.MethodsWe present a case report, including scintigraphic and histologic documentation, and a summary of the related literature.ResultsPrimary hyperparathyroidism with concomitant occurrence of nonmedullary thyroid carcinoma is rare, occurring in less than 4% of patients. We report a case of a 53-year-old woman with no prior history of endocrine disease with primary hyperparathyroidism and an incidental finding of a concurrent thyroid carcinoma. In this patient, technetium 99m scintigraphy revealed a parathyroid adenoma beneath the inferior pole of the left thyroid bed. Parathyroidectomy was performed successfully with no complications. The final pathology examination showed a large parathyroid adenoma with an incidental finding of a small adjacent lymph node containing metastatic papillary thyroid carcinoma. The patient subsequently underwent total thyroidectomy, and the pathology evaluation revealed papillary thyroid carcinoma, follicular variant.ConclusionTo our knowledge, this case of concomitant primary hyperparathyroidism and papillary thyroid cancer is unique in the way in which the diagnosis of metastatic papillary thyroid cancer was made. The presence of parathyroid adenoma should not exclude the diagnosis of thyroid carcinoma; therefore, careful thyroid evaluation should be considered for all patients with primary hyperparathyroidism. (Endocr Pract. 2007;13:380-383)     

Clinical Aspects of Hyperthyroidism,Hypothyroidism, and Thyroid Screening in Pregnancy

ObjectiveTo evaluate the peer-reviewed literature on hypothyroidism, hyperthyroidism, and thyroid autoimmunity in pregnancy.MethodsWe review published studies on thyroid autoimmunity and dysfunction in pregnancy, the impact of thyroid disease on pregnancy, and discuss implications for screening.ResultsOvert hyperthyroidism and hypothyroidism are responsible for adverse obstetric and neonatal events. Several studies of association suggest that either subclinical hypothyroidism or thyroid autoimmunity increase the risk of complications. One randomized controlled trial showed that pregnant women with subclinical hypothyroidism benefit from treatment in terms of obstetric and neonatal complications, whereas another study demonstrated no benefit in the intelligence quotient of babies born to women with subclinical hypothyroidism. Thyroid autoimmunity has been associated with increased rate of pregnancy loss, recurrent miscarriage, and preterm delivery.ConclusionCurrent guidelines agree that overt hyperthyroidism and hypothyroidism need to be promptly treated and that as potential benefits outweigh potential harm, subclinical hypothyroidism also requires substitutive treatment. The chance that women with thyroid autoimmunity may benefit from levothyroxine treatment to improve obstetric outcome is intriguing, but adequately powered randomized controlled trials are needed. The issue of universal thyroid screening at the beginning of pregnancy is still a matter of debate, and aggressive case-finding is supported. (Endocr Pract. 2014;20:597-607)     

Parathyroidectomy-Induced Thyroiditis

ObjectiveTo highlight the possibility of development of thyroiditis after parathyroidectomy.MethodsClinical and laboratory findings in 2 cases are presented, and the relevant literature is reviewed.ResultsIn 2 women (84 years old and 55 years old) with no history of thyroid disease in one of them and a remote history of excision of a follicular adenoma in the other, thyrotoxicosis developed a few days to a week after parathyroidectomy for primary hyperparathyroidism. The first patient underwent bilateral cervical exploration with removal of a right inferior parathyroid adenoma, whereas the second patient had excision of 3¹/₂ parathyroid glands for 4-gland hyperplasia and 2 benign nodules from the left thyroid lobe. Both surgical procedures were uncomplicated. Neither patient had received any iodinated contrast agents or medications such as lithium or amiodarone before presentation. Laboratory results showed elevated levels of free thyroxine, suppressed thyroid-stimulating hormone levels, very low radioiodine uptake (in the second patient), and an elevated thyroglobulin level (in the first patient). Both patients were treated symptomatically with β-adrenergic antagonists. Thyroid function normalized and symptoms diminished after 1 to 2 months.ConclusionParathyroidectomy-induced thyroiditis is underrecognized. The majority of patients are asymptomatic, although clinically significant thyrotoxicosis can also occur. Candidates for parathyroidectomy should be informed of this potential complication, and thyroid function should be assessed if clinically indicated. (Endocr Pract. 2010;16:656-659)