Diabetes Insipidus in Pregnancy: Etiology,Evaluation, and Management

ObjectiveTo review the approach to a patient with diabetes insipidus during pregnancy.MethodsThis review examines the normal physiology of water homeostasis, the related changes that occur during pregnancy, and the pathophysiology of diabetes insipidus in pregnancy. Associated complications, evaluation, and management are discussed.ResultsDiabetes insipidus can complicate up to 1 in 30000 pregnancies. Diabetes insipidus during pregnancy has a variety of causes, some that predate the pregnancy and others that begin during gestation. Polyuria and polydipsia can occur or be exacerbated in women with overt or subclinical central or nephrogenic diabetes insipidus. These women have either decreased central secretory reserve or impaired renal responsiveness to vasopressin. In addition, women can experience diabetes insipidus de novo in pregnancy through the actions of placental vasopressinase, which causes accelerated degradation of vasopressin. This form of diabetes insipidus may be associated with increased complications of pregnancy, including preeclampsia. Management of central diabetes insipidus and transient diabetes insipidus of pregnancy can be achieved with 1-deamino-8-D-arginine vasopressin (desmopressin acetate) (DDAVP), a vasopressin analogue. Nephrogenic diabetes insipidus is typically resistant to both DDAVP and vasopressin and underlying causes should be addressed.ConclusionsIncreased awareness of diabetes insipidus in pregnancy may lead to early diagnosis and appropriate treatment that will reduce the risks of maternal and fetal morbidity. Overall, growing experience with DDAVP has shown that it is a safe and effective treatment for diabetes insipidus caused by a variety of factors. (Endocr Pract. 2009;15:377-382)     

Sheehan Syndrome Presenting as Central Diabetes Insipidus: A Rare Presentation of an Uncommon Disorder

ObjectiveTo add to the current scant literature on rare clinical presentations of Sheehan syndrome.MethodsWe describe the study patient’s clinical, laboratory, and imaging findings and review the literature for publications regarding varied clinical presentations of Sheehan syndrome.ResultsA 36-year-old multigravida woman developed severe postpartum hemorrhage and disseminated intravascular coagulation followed by Sheehan syndrome, with central diabetes insipidus as the primary presenting feature. This was diagnosed when, postoperatively, she developed polyuria with a urine output of 11 L in 24 hours with an accompanying rise in creatinine. She had laboratory evidence of diabetes insipidus, with serum osmolality greater than urine osmolality. Her clinical status improved significantly with intranasal desmopressin supplementation, thus confirming the diagnosis of Sheehan syndrome. Although Sheehan syndrome is a known complication of postpartum hemorrhage, central diabetes insipidus is seldom considered or suspected. Hypovolemia is usually presumed to be secondary to blood loss and polyuria resulting from a diuretic phase of acute renal failure.ConclusionsIt is important to consider posterior pituitary ischemia resulting from Sheehan syndrome presenting as central diabetes insipidus as a cause of polyuria because appropriate hormonal replacement initiated early can possibly improve clinical status and patient outcomes. (Endocr Pract. 2011;17:108-114)     

A Combined Outpatient and Inpatient Overnight Water Deprivation Test is Effective and Safe in Diagnosing Patients with Polyuria-Polydipsia Syndrome

Objective: The water deprivation test (WDT) is widely used for the differential diagnosis of the polyuria-polydipsia syndrome (PPS). However, it is inconvenient and may not always be precise in differentiating partial forms of diabetes insipidus (DI) from primary polydipsia (PP). The aim of this study was to evaluate the results of a combined outpatient and inpatient overnight WDT protocol that included an overnight unsupervised period concerning its feasibility and safety.Methods: We performed a retrospective analysis of clinical data and laboratory results of 52 patients with PPS undergoing WDT at a single center.Results: PP was the most frequent diagnosis, followed by complete central DI (cCDI), partial central DI (pCDI), and nephrogenic DI (NDI). Over 90% of the patients showed an expected increase in serum osmolality at the end of the dehydration period. There were no reports of complications during the overnight deprivation period. Post-dehydration urine osmolality and urine-to-serum osmolality ratio significantly differentiated all the groups (P<.05), except for cCDI and NDI, which could be differentiated by basal and post-dehydration vasopressin (AVP) levels (P<.05 for both). Although these measurements were useful for differentiating patients according to their allocation groups, results from WDT and direct AVP levels may often require a comprehensive diagnostic approach, particularly in the challenging groups of PP and pCDI.Conclusion: A combined outpatient and inpatient overnight WDT protocol is safe and feasible when the test is performed with special care at experienced centers. Newer diagnostic tools are expected to improve the accuracy of PPS diagnosis.Abbreviations: AQP2 = aquaporin-2; AVP = vasopressin; CDI = central diabetes insipidus; cCDI = complete central diabetes insipidus; DDAVP = desmopressin; DI = diabetes insipidus; IQR = interquartile range; MRI = magnetic resonance imaging; Na⁺ = sodium; NDI = nephrogenic diabetes insipidus; pCDI = partial central diabetes insipidus; PP = primary polydipsia; PPS = polyuria-polydipsia syndrome; S_osm = serum osmolality; U_osm = urine osmolality; WDT = water deprivation test     

Primary hyperparathyroidism and familial hypocalciuric hypercalcemia: relationships and clinical implications

ObjectiveTo discuss the unusual occurrence of both familial hypocalciuric hypercalcemia (FHH) and primary hyperparathyroidism in the same patient and to explore potential mechanisms of association and issues related to clinical management.MethodsWe discuss the diagnosis, compare the clinical presentations of FHH and primary hyperparathyroidism, review the literature regarding patients who have presented with both disorders, and discuss management considerations. We also describe 2 patients who have both FHH (confirmed by genetic testing for a mutation in the gene encoding the calcium-sensing receptor [CASR]) and primary hyperparathyroidism.ResultsThe occurrence of both FHH and primary hyperparathyroidism in the same patient has been reported in a few cases, including 2 patients described here, one of whom was documented to have a novel CASR mutation. Inthose with clinical sequelae of hyperparathyroidism, parathyroidectomy has led to reduction, but not normalization, of serum calcium levels.ConclusionsThe coexistence of FHH and primary hyperparathyroidism should be considered in patients with hypercalcemia, hypophosphatemia, frankly elevated parathyroid hormone levels, and low urinary calcium excretion. Genetic testing for inactivating CASR gene mutations can confirm the diagnosis of FHH. Although surgical intervention does not resolve hypercalcemia, it may be beneficial by reducing the degree of hypercalcemia, alleviating the symptoms, and preventing potential complications of hyperparathyroidism. (Endocr Pract. 2012;18:412-417)     

Xanthogranuloma as an Unsuspected Cause of Idiopathic Central Diabetes Insipidus

ObjectiveTo demonstrate that xanthogranuloma is a rare cause of idiopathic central diabetes insipidus in the early phase of the disease and that it presents as a suprasellar mass at a later stage. In addition, we emphasize the importance of identifying the cause of idiopathic central diabetes insipidus and review the literature concerning endocrine disturbance in central xanthogranuloma.MethodsReview of recently published case reports of central xanthogranuloma with endocrine disorders. The case of a 35-year-old man who presented with a very large suprasellar mass is also reported. The patient was diagnosed with idiopathic central diabetes insipidus 20 years ago with normal brain magnetic resonance imaging.ResultMost cases of this disease present as supra-or parasellar masses with endocrine involvement, the most common of which (in approximately 75% of patients) is sex hormone deficiency. Diabetes insipidus was found in 65% of patients.ConclusionXanthogranuloma should be in the differential diagnosis of idiopathic central diabetes insipidus and sellar and parasellar masses. A detailed skin examination is very important in making the diagnosis of central diabetes insipidus. (Endocr Pract. 2014;20:e42-e46)     

Hyperparathyroid Crisis Due to Asymmetric Parathyroid Hyperplasia with A Massive Ectopic Parathyroid Gland

ObjectiveTo report a rare case of primary hyperparathyroidism presenting with hyper-parathyroid crisis due to parathyroid hyperplasia with ectopic glands.MethodsWe present the initial clinical manifestations, laboratory results, radiologic and surgical findings, and management in a patient who had hyper-parathyroid crisis. The pertinent literature and management options are also reviewed.ResultsA 60-year-old female presented with hyper-parathyroid crisis requiring preoperative stabilization with rehydration, diuresis, bisphosphonate therapy, and ultimately hemodialysis. Parathyroidectomy revealed asymmetric 4-gland hyperplasia, with a massive ectopic parathyroid gland in the tracheoesophageal groove extending into the mediastinum. Her postoperative course was complicated by hungry bone syndrome and hypocalcemia.ConclusionThis case illustrates the rare occurrence of hyper-parathyroid crises due to asymmetric parathyroid hyperplasia with a massive ectopic parathyroid gland. (Endocr Pract. 2014;20:e180-e182)     

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)     

An Unusual Case of Recurrent Hyperparathyroidism and Papillary Thyroid Cancer

ObjectiveTo report an unusual occurrence of recurrent hyperparathyroidism due to papillary thyroid carcinoma.MethodsWe describe the clinical history, physical examination findings, laboratory values, imaging findings, and pathologic findings of a woman who developed recurrent hyperparathyroidism 13 years after successful parathyroidectomy.ResultsA 59-year-old woman presented to our clinic with recurrent primary hyperparathyroidism. In 1994, she presented with nephrolithiasis and underwent resection of a right superior parathyroid adenoma that resulted in clinical and biochemical cure. Her clinical course had been followed at periodic intervals, and she had been symptom-free and normocalcemic. In 2007, she again developed nephrolithiasis and was documented to have recurrent hyperparathyroidism. Imaging studies suggested a parathyroid adenoma near the right inferior pole of the thyroid. The patient had reoperative neck exploration. No obvious parathyroid adenoma was found and a right thyroid lobectomy was performed, which resulted in normalization of intraoperative intact parathyroid hormone levels, and the incision was closed. Final pathology demonstrated no parathyroid adenoma, but instead, a 1-cm papillary thyroid carcinoma that stained positive for parathyroid hormone. More than 6 months after surgery, she remains clinically and biochemically cured.ConclusionsRecurrent hyperparathyroidism occurs secondary to multiple causes. This case demonstrates the challenge a surgeon faces in managing recurrent disease and highlights a rare phenomenon of papillary thyroid cancer causing recurrent hyperparathyroidism. (Endocr Pract. 2009;15:349-352)     

Xanthoma Disseminatum: Case Report and Literature Review

ObjectiveTo report a case of a young normolipidemic woman with mucocutaneous xanthomas who developed neurogenic diabetes insipidus and hyperprolactinemia because of an inflammatory pituitary stalk lesion.MethodsThe clinical features, laboratory results, magnetic resonance imaging, and pathology findings are presented. In addition, the pertinent literature is reviewed.ResultsA 23-year-old woman presented with a 9-month history of polydipsia, polyuria, galactorrhea, secondary amenorrhea, and weight gain. Her previous medical history included chronic anemia and widespread mucocutaneous xanthomas. Laboratory tests showed hyperprolactinemia, normal electrolytes, and a normal lipid profile. The results of a water deprivation test were compatible with neurogenic diabetes insipidus, and cerebral magnetic resonance imaging showed pituitary stalk thickening. Histologic findings on a skin biopsy specimen supported the diagnosis of non-Langerhans histiocytosis. Treatment was initiated with cabergoline, nasally administered desmopressin, radio-frequency ablation of facial skin lesions, and surgical excision of other accessible lesions.ConclusionXanthoma disseminatum is a rare, benign proliferative disorder characterized by extensive cutaneous and mucous membrane xanthomas in normolipidemic patients. Central nervous system involvement is rare and usually occurs in the systemic variety. Pituitary stalk disease commonly causes hyperprolactinemia, diabetes insipidus, and various degrees of hypopituitarism. The natural history of xanthoma disseminatum usually is benign, but lesions in critical anatomic sites may result in morbidity and mortality. (Endocr Pract. 2010;16:1003-1006)     

Unusual Case of Calciphylaxis Associated with Primary Hyperparathyroidism Without Coexistent Renal Failure

ObjectiveTo report a case of calciphylaxis in a patient with primary hyperparathyroidism without coexistent renal failure.MethodsThe clinical, laboratory, and radiographic details of this case are reviewed, and the pathogenesis of calciphylaxis and the associated prognosis are discussed.ResultsA 52-year-old woman had progressive fatigue, cachexia, severe osteoporosis, and necrotizing skin lesions. Her serum calcium level was 16 mg/dL, serum phosphorus level was 2.13 mg/dL, and parathyroid hormone level was 2,257 pg/mL (reference range, 15 to 65). On physical examination, gangrenous skin lesions with black crusts were noted on her legs, abdomen, and gluteal region. A mass lesion was detected in the parathyroid region by both ultrasonography and a parathyroid scan. The patient underwent a bilateral neck exploration, and a parathyroid adenoma measuring 3.5 by 1.5 by 1.2 cm was found on pathologic examination. After the operation, biochemical findings normalized, and the skin lesions progressively improved.ConclusionSevere primary hyperparathyroidism may be a factor leading to calciphylaxis, even in the absence of renal failure and a high calcium-phosphate product. This potentially life-threatening condition should not be left untreated if the levels of serum calcium and parathyroid hormone are severely elevated. (Endocr Pract. 2008;14:368-372)     

Prevalence of Type 2 Diabetes Mellitus In Patients With Primary Hyperparathyroidism

IntroductionTo determine the prevalence of type 2 diabetes mellitus (DM) in patients with primary hyperparathyroidism.MethodsPrevalence of type 2 DM in 609 patients with surgically verified primary hyperparathyroidism presenting between 1992 and 2003 in a tertiary care hospital setting was assessed retrospectively and compared with published data of type 2 DM prevalence in Michigan’s general population. Diagnosis of type 2 DM was made on the basis of documentation in the medical record of fasting or random blood glucose level thresholds according to the 1997 American Diabetes Association criteria, history of diabetes mellitus, or therapy with antidiabetic medications.ResultsThe crude prevalence rate of type 2 DM in patients with primary hyperparathyroidism was significantly higher than the prevalence in the Michigan general population (15.9% vs 7.8%, respectively; P < .001). However, this difference was not significant after age stratification except for the age group of 64 to 75 years. Because of the differential distribution of participants across age categories in the 2 groups, a standardized prevalence ratio (SPR) was estimated to account for the variance. After adjustment, there was no significant difference in the prevalence of DM between patients with primary hyperparathyroidism and the control population (SPR, 1.19 [95% confidence interval, 0.96-1.45]) except in men.ConclusionThe reported higher prevalence of type 2 DM in patients with primary hyperparathyroidism could not be confirmed in this large cohort of patients except for in older patients and in men. Because of the retrospective nature the study and the lack of appropriate controls, further studies are needed to confirm or refute these findings. (Endocr Pract. 2008;14:69-75)     

Diabetes Insipidus Associated with Hehmophagocytic Lymphohistiocytosis: First Case Report

ObjectiveTo report the first case of central diabetes insipidus associated with hemophagocytic lymphohistiocytosis.MethodsWe describe the clinical course of a 75-yearold woman who developed febrile illness 1 month after receiving the H1N1 influenza vaccination. Shortly thereafter, she developed central diabetes insipidus, which responded to treatment with intranasal desmopressin acetate. She was then hospitalized with another febrile illness and diagnosed with hemophagocytic lymphohistiocytosis.ResultsMagnetic resonance imaging of the pituitary gland was significant for plaquelike meningeal enhancement and thickening surrounding the infundibulum, which has been previously reported as a manifestation of histiocytosis.ConclusionWe believe this is the first case of central diabetes insipidus associated with hemophagocytic lymphohistiocytosis. (Endocr Pract. 2011;17:e118-e122)     

Graves Hyperthyroidism and Pregnancy: A Clinical Update

ObjectiveTo provide a clinical update on Graves’ hyperthyroidism and pregnancy with a focus on treatment with antithyroid drugs.MethodsWe searched the English-language literature for studies published between 1929 and 2009 related to management of hyperthyroidism in pregnancy. In this review, we discuss differential diagnosis of hyperthyroidism, management, importance of early diagnosis, and importance of achieving proper control to avoid maternal and fetal complications.ResultsDiagnosing hyperthyroidism during pregnancy can be challenging because many of the signs and symptoms are similar to normal physiologic changes that occur in pregnancy. Patients with Graves disease require prompt treatment with antithyroid drugs and should undergo frequent monitoring for signs of fetal and maternal hyperthyroidism and hypothyroidism. Rates of maternal and perinatal complications are directly related to control of hyperthyroidism in the mother. Thyroid receptor antibodies should be assessed in all women with hyperthyroidism to help predict and reduce the risk of fetal or neonatal hyperthyroidism or hypothyroidism. The maternal thyroxine level should be kept in the upper third of the reference range or just above normal, using the lowest possible antithyroid drug dosage. Hyperthyroidism may recurin the postpartum period as Graves disease or postpartum thyroiditis; thus, it is prudent to evaluate thyroid function 6 weeks after delivery. Preconception counseling, a multidisciplinary approach to care, and patient education regarding potential maternal and fetal complications that can occur with different types of treatment are important.ConclusionPreconception counseling and a multifaceted approach to care by the endocrinologist and the obstetric team are imperative for a successful pregnancy in women with Graves hyperthyroidism. (Endocr Pract. 2010;16:118-129)     

Primary Hyperparathyroidism

ObjectiveTo review primary hyperparathyroidism and the key issues that are relevant to the practicing endocrinologist.MethodsThe latest information on the presentation, diagnosis, and traditional and nontraditional aspects of primary hyperparathyroidism is reviewed.ResultsThe diagnosis of primary hyperparathyroidism is straightforward when the traditional hypercalcemic patient is documented to have an elevated parathyroid hormone (PTH) level. Commonly, patients are identified who have normal serum calcium levels but elevated PTH levels in whom no secondary causes for hyperparathyroidism can be confirmed. Traditional target organs of primary hyperparathyroidism—the skeleton and the kidneys—continue to be a focus in the patient evaluation. Bone mineral density shows a typical pattern of involvement with the distal one-third radius being selectively reduced compared with the lumbar spine in which bone mineral density is generally well maintained. Neurocognitive and cardiovascular aspects of primary hyperparathyroidism, while a focus of recent interest, have not been shown to definitively aid in the decision for or against surgery. The recommendation for surgery in primary hyperparathyroidism is based on guidelines that focus on the serum calcium level, renal function, bone mineral density, and age. In patients who do not meet guidelines, a nonsurgical management approach has merit.ConclusionsPrimary hyperparathyroidism is continuing to show changes in its clinical profile, with normocalcemic primary hyperparathyroidism being a topic of great interest. Skeletal and renal features of primary hyperparathyroidism drive, in most cases, the decision to recommend surgery. In patients who do not meet any criteria for surgery, a conservative approach with appropriate monitoring is acceptable. (Endocr Pract. 2012;18:781-790)     

A Stepwise Approach to the Evaluation and Treatment of Subclinicalhyperthyroidism

ObjectivesTo review a stepwise approach to the evaluation and treatment of subclinical hyperthyroidism.MethodsEnglish-language articles regarding clinical management of subclinical hyperthyroidism published between 2007 and 2012 were reviewed.ResultsSubclinical hyperthyroidism is encountered on a daily basis in clinical practice. When evaluating patients with a suppressed serum thyrotropin value, it is important to exclude other potential etiologies such as overt triiodothyronine toxicosis, drug effect, nonthyroidal illness, and central hypothyroidism. In younger patients with mild thyrotropin suppression, it is acceptable to perform testing again in 3 to 6 months to assess for persistence before performing further diagnostic testing. In older patients or patients with thyrotropin values less than 0.1 mIU/L, diagnostic testing should proceed without delay. Persistence of thyrotropin suppression is more typical of nodular thyroid autonomy, whereas thyroiditis and mild Graves disease frequently resolve spontaneously. The clinical consequences of subclinical hyperthyroidism, such as atrial dysrhythmia, accelerated bone loss, increased fracture rate, and higher rates of cardiovascular mortality, are dependent on age and severity. The decision to treat subclinical hyperthyroidism is directly tied to an assessment of the potential for clinical consequences in untreated disease. Definitive therapy is generally selected for patients with nodular autonomous function, whereas antithyroid drug therapy is more appropriate for mild, persistent Graves disease.ConclusionThe presented stepwise approach to the care of patients presenting with an isolated suppression of serum thyrotropin focuses on the differential diagnosis, a prediction of the likelihood of persistence, an assessment of potential risks posed to the patient, and, finally, a personalized choice of therapy. (Endocr Pract. 2012;18: 772-780)     

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)     

Lithium Andadjunct to Radioactive Iodine for the Treatment of Hyperthyroidism: A Systematic Review and Meta-Analysis

BackgroundRadioactive iodine (RAI) is commonly used in the treatment of hyperthyroidism but is not uniformly successful. Lithium increases thyroidal iodine retention without reducing iodide uptake, increasing the radiation dose to the thyroid when administered with RAI. Although these actions suggest that adjuvant lithium may increase the efficacy of RAI, its role as an adjunct to RAI remains contentious.ObjectiveTo evaluate the safety and efficacy of adding lithium to RAI to treat hyperthyroidism.MethodsRelevant studies were identified by a search of Medline and the Cochrane Central Register of Controlled Trials. To be included, a study had to be a controlled trial comparing the effect of RAI alone to RAI with lithium in the treatment of hyperthyroidism. Relevant data were extracted and meta-analyses were performed.ResultsOf the 75 identified studies, 6 met the inclusion criteria; 4 of these studies were interventional and 2 were observational trials. Meta-analysis of the observational trials (N = 851), both of which were retrospective cohort studies, showed significant improvement in the primary outcome (i.e., cure rate) with adjunctive lithium (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.24 to 2.96). The combined interventional trials (N = 485) also showed an improvement in cure rate, but the difference did not reach statistical significance (OR, 1.28; 95% CI, 0.85 to 1.91). Adjunctive lithium reduced time to cure and blunted thyroid hormone excursions after RAI. Lithiumrelated side effects were infrequent and usually mild.ConclusionThe observational trials demonstrated significant improvement in the cure rate of hyperthyroidism when lithium is added to RAI. The improvements shown in the interventional trials did not reach statistical significance due to the effect of a single, large negative trial. (Endocr Pract. 2014;20:737-745)     

Heart Failure in Hypophosphatemic Rickets: Complications from High-Dose Phosphate Therapy

ObjectiveTo report a rare case of hypophosphatemic rickets (HR) leading to extensive cardiac complications.MethodsWe present the clinical course and autopsy findings of a patient with HR, treated with chronic phosphate-only therapy as a child, who subsequently developed tertiary hyperparathyroidism leading to extensive cardiac calcifications and complications. We also review the literature on the pathophysiology of calcifications from HR.ResultsA 34-year-old man was diagnosed with HR at 4 years of age after presenting with growth delay and leg bowing. Family history was negative for the disease. He was initiated on high-dose phosphate therapy (2-6 g of elemental phosphorus/day) with sporadic calcitriol use between 4-18 years of age. For 6 years he received phosphate-only therapy. Subsequently, he developed nephrocalcinosis, heart valve calcifications, severe calcific coronary artery disease, heart block, and congestive heart failure. At a young age, he required an aortic valve replacement and a biventricular pacemaker that was subsequently upgraded to an implantable cardioverter defibrillator. Autopsy showed extensive endocardial, myocardial, and coronary artery calcifications.ConclusionCardiac calcification is a known sequela of tertiary hyperparathyroidism when it occurs in patients with renal failure, but it is rarely seen in HR due to high phosphate therapy. Phosphate alone should never be used to treat HR; high doses, even with calcitriol, should be avoided. It is important to be cognizant of high-dose phosphate effects and to consider parathyroidectomy for autonomous function, if needed. This case emphasizes the importance of appropriate therapy, monitoring, and management of patients with HR. (Endocr Pract. 2013;19:e8-e11)     

Preoperative and Postoperative Evaluation of Thyroid Disease in Patients Undergoing Surgical Treatment of Primary Hyperparathyroidism

ObjectiveTo evaluate the occurrence of thyroid disease in patients undergoing parathyroidectomy for primary hyperparathyroidism.MethodsIn this case series, records of all patients with a diagnosis of primary hyperparathyroidism who underwent parathyroidectomy between January 2005 and December 2008 in our clinic were analyzed retrospectively. Preoperatively, all patients were evaluated with ultrasonography and parathyroid scintigraphy; when needed, thyroid scintigraphy and ultrasound-guided fine-needle aspiration biopsy (FNAB) were used. All patients underwent standard neck exploration. Postoperative histopathologic findings of thyroid tissue were classified as nodular/ multinodular hyperplasia, Hashimoto thyroiditis, papillary thyroid carcinoma, or normal.ResultsFifty-one women and 9 men were included. In the 60 patients, preoperative ultrasonography revealed thyroiditis (without nodules) in 13 (22%), a solitary nodule in 9 (15%) (coexistent with thyroiditis in 7 patients), multinodular goiter in 24 (40%) (coexistent with thyroiditis in 5 patients), and normal findings in 14 (23%). Rates of thyroiditis and nodular goiter were 42% and 55%, respectively. Collectively, prevalence of thyroid disease was 77%. Total thyroidectomy was performed in 27 patients, and hemithyroidectomy was performed in 15 patients. Indications for total thyroidectomy were nondiagnostic or suspicious FNAB results in 5 patients, hyperthyroidism in 4 patients, ultrasonography findings in 11 patients, and intraoperatively recognized suspicious nodularity in 7 patients. Postoperatively, thyroid carcinoma was diagnosed in 9 patients (15%).ConclusionsThyroid disease, particularly thyroid carcinoma, is common in patients with primary hyperparathyroidism. This association should be considered when selecting the surgical procedure. Intraoperative evaluation of the thyroid is as important as preoperative evaluation with ultrasonography and FNAB in patients with thyroid disease and primary hyperparathyroidism. (Endocr Pract. 2010;16:7-13)     

Thyrotropin-Secreting Adenoma in a Patient with Primary Hypothyroidism

ObjectiveTo describe a patient who developed a thyrotropin (TSH)-Secreting adenoma in the setting of primary hypothyroidism.MethodsWe report the clinical, laboratory, and radiologic findings of a patient with a history of primary hypothyroidism who presented with headache, a bitemporal visual field deficit, and elevated TSH despite long-term levothyroxine therapy. We discuss the diagnostic challenges of this case and review the relevant literature.ResultsA54-year-old woman with a history of primary hypothyroidism presented with a 3-year history of headache and a week of worsening vision. Imaging revealed a heterogeneous sellar mass elevating the optic chiasm. Her serum TSH was 46.5 mIU/L and free thyroxine concentration was 0.1 ng/dL. The differential diagnosis included pituitary hyperplasia and a TSH-secreting adenoma in a patient with primary hypothyroidism. The pathologic characteristics of the tumor were consistent with the latter.ConclusionIn a patient with an elevated TSH concentration and a previous diagnosis of hypothyroidism, it is important to consider other entities besides medication noncompliance. TSH-secreting adenomas can also cause elevated levels of TSH. (Endocr Pract. 2011;17: e135-e139)