Reduced estrogen in menopause may predispose women to takotsubo cardiomyopathy

Background: Takotsubo cardiomyopathy (apical ballooning syndrome) has been reported with increased frequency, most commonly in postmenopausal women. Despite the gender disparity, no clear link between estrogen and its possible cardioprotective effects has been shown.Objectives: We present a case series of takotsubo cardiomyopathy in women and examine the prevalence of estrogen replacement therapy (ERT), in addition to conducting a systematic literature review on this topic.Methods: Consecutive cases of takotsubo cardiomyopathy were identified at our institution, Cleveland Clinic Florida, from January 2006 to December 2008, and patient-level data were extracted for analysis. For the literature review, we searched the MEDLINE database from January 1990 to March 2008 for English-language publications, using the terms apical ballooning syndrome, takotsubo, and stress cardiomyopathy, and identified case reports and series of takotsubo cardiomyopathy. Articles describing female patients and their medication use at time of presentation were included in the study.Results: Eighteen cases of takotsubo cardiomyopathy were identified at our institution, all in postmenopausal women except for 2 who were still menstruating. Of the 16 postmenopausal cases, none were taking ERT at time of presentation. From the literature review, >400 publications were queried, of which 296 were recognized as case reports or series, with 7 articles meeting all of our inclusion criteria. From these reports, 13 women were identified, none of whom were taking ERT at time of presentation.Conclusions: Lack of estrogen replacement in the postmenopausal state may predispose women to takotsubo cardiomyopathy. Further studies are needed to establish the link more firmly.     

The Emerging Role of Denosumab in the Long-Term Management of Parathyroid Carcinoma-Related Refractory Hypercalcemia

Objective: The main cause of death in patients with parathyroid carcinoma is parathyroid hormone (PTH)-induced hypercalcemia. To date, the management of hypercalcemia has been based on the use of bisphosphonates and calcimimetic agents. In recent reports, the use of denosumab has shown encouraging results in cases of refractory hypercalcemia of malignancy. Our objective is to present a case of successful management of resistant hypercalcemia due to parathyroid carcinoma with denosumab, to review similar cases from the literature, and to propose denosumab's use in the clinical management of PTH-induced refractory hypercalcemiaMethods: Presentation of a case report and review of the literature for cases of parathyroid carcinoma–mediated hypercalcemia successfully treated with denosumab.Results: A 71-year-old man with metastatic parathyroid carcinoma was referred to our department for uncontrolled hypercalcemia, resistant to treatment with bisphosphonates and cinacalcet. Treatment with denosumab (120 mg per month) in addition to cinacalcet (180 mg per day) resulted in normalization of calcium levels and maintenance within the normal range for an observation period of 11 months. Review of the literature revealed 4 case reports and a letter to the editor, all of which reported the successful treatment of resistant hypercalcemia associated with parathyroid carcinoma.Conclusion: Based on the above findings of the effectiveness of denosumab in controlling refractory hypercalcemia, its safety in renal failure and the fact that denosumab may reduce PTH-induced bone loss, we endorse its use in the management of hypercalcemia in patients with parathyroid carcinoma and perhaps other conditions with PTH-induced hypercalcemia.Abbreviations: CT = computed tomography IV = intravenous PTH = parathyroid hormone     

Genetic Basis of Bilateral Macronodular Hyperplasia

Objective: To review the genetic basis of bilateral macronodular hyperplasia (BMAH).Methods: Case presentation, review of literature, table, and bullet point conclusions.Results: BMAH, also known as adrenocorticotropic hormone (ACTH)-independent macronodular hyperplasia (AIMH), can cause Cushing syndrome or mild hypercortisolism. Recent studies have demonstrated that hyperplastic tissue reproduces ectopic ACTH, implying that BMAH is the more proper term, as the syndrome is not ACTH-independent. BMAH was thought to be sporadic, but recent data have shown that there is likely a genetic component in the majority of cases. Mutations in ARMC5, a putative suppressor gene, have been found in many familial cases of BMAH and are thought to be responsible for the disorder. As these nodules inefficiently produce cortisol, large nodules are required to produce a clinical syndrome. ARMC5 likely requires a second somatic mutation to become clinically apparent. Clinical manifestations are not generally noted until the fifth to sixth decades of life.Conclusion: BMAH is an underrecognized genetic condition that can lead to Cushing syndrome and should be screened for in patients and susceptible family members.Abbreviations: ACTH = adrenocorticotropic hormone AIMAH = ACTH-independent macronodular adrenal hyperplasia ARMC5 = armadillo-repeat containing 5 BMAH = bilateral macronodular adrenal hyperplasia CAH = congenital adrenal hyperplasia CT = computed tomography MEN1 = multiple endocrine neoplasia 1 UFC = urinary free cortisol     

Historical and Current Perspective in the Use of Thyroid Extracts for the Treatment of Hypothyroidism

Objective: To describe the history, refinements, implementation, physiology, and clinical outcomes achieved over the past several centuries of thyroid hormone replacement strategies.Methods: A Medline search was initiated using the following search terms: bioidentical thyroid hormone, thyroid hormone extract, combination thyroxine (T4) and tri-iodothyronine (T3) therapy, homeopathic thyroid hormone therapy, and thyroid hormone replacement. Pertinent articles of interest were identified by title (and where available abstract) for further review. Additional references were identified during a review of the identified literature.Results: A rich history of physician intervention in thyroid dysfunction was identified dating back more than 2 millennia. Although not precisely documented, thyroid ingestion from animal sources had been used for centuries but was finally scientifically described and documented in Europe over 130 years ago. Since the reports by Bettencourt and Murray, there has been a continuous documentation of outcomes, refinement of hormone preparation production, and updating of recommendations for the most effective and safe use of these hormones for relieving the symptoms of hypothyroidism. As the thyroid extract preparations contain both levothyroxine (LT4) and liothyronine (LT3), current guidelines do not endorse their use as controlled studies do not clearly document enhanced objective outcomes compared with LT4 monotherapy. Among current issues cited, the optimum ratio of LT4 to LT3 has yet to be determined, and the U.S. Food and Drug Administration (FDA) does not appear to be monitoring the thyroid hormone ratios or content in extract preparations on the market. Taken together, these limitations are important detriments to the use of thyroid extract products.Conclusion: The evolution of thyroid hormone therapies has been significant over the extended period of time they have been in use to treat hypothyroidism. Although numerous websites continue to advocate the use of thyroid hormone extracts as a superior therapy for hypothyroidism, none of the most recent guidelines of major endocrine societies recommend thyroid extract use for hypothyroidism.Abbreviations: AACE = American Association of Clinical Endocrinologists ATA = American Thyroid Association BMR = basal metabolic rate FDA = Food and Drug Administration FT4 = free thyroxine 131-I = radioactive iodine 131 LT3 = liothyronine LT4= levothyroxine NDA = new drug application PBI = proteinbound iodine T3 = triiodothyronine T4 = thyroxine TSH = thyroid-stimulating hormone TT3 = total triiodothyronine USP = U.S. Pharmacopeia     

Familial Chylomicronemia Syndrome: A Clinical Guide for Endocrinologists

Objective: Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder caused by mutations in lipoprotein lipase, resulting in accumulation of chylomicrons in plasma and hypertriglyceridemia. Elevated triglycerides cause several complications in patients, the most serious being episodes of acute pancreatitis. This review focuses on expert guidance and opinion from an experienced lipidologist and endocrinologist as well as a current review of the literature, as there are no specific guidelines on FCS.Methods: Discussion of expert guidance and opinion review of current literature.Results: To date, there is no pharmacologic treatment for affected patients, and management options primarily include adoption of an extremely restricted, very-low-fat diet, along with avoidance of certain medications and alcohol. Endocrinologists often diagnose and manage patients with metabolic disorders, including patients with high triglyceride levels, but rare diseases like FCS can be missed or poorly evaluated due to knowledge gaps about disease state. Given endocrinologists' role in the treatment of lipid disorders, it is important that they understand the clinical signs and symptoms of FCS to correctly diagnose patients. Patients with FCS can be identified based on a defined clinical criteria and a thorough review of medical history, after excluding differential diagnoses and secondary factors. Typical manifestations include hypertriglyceridemia characterized by lipemic serum, history of abdominal pain, and acute/recurrent pancreatitis. Secondary factors to be excluded are pregnancy, alcohol abuse, uncontrolled diabetes, and use of certain medications.Conclusion: FCS is a rare, inherited lipid disorder disease that often goes underdiagnosed and unmanaged. This review provides a summary of clinical characteristics of FCS that can be potentially used to screen patients in an endocrinologist's office and direct them to the appropriate standard of care.Abbreviations: apoB = apolipoprotein B; apoC-III = apolipoprotein CIII; ASO = antisense oligonucleotide; FCS = familial chylomicronemia syndrome; HTG = hypertriglyceridemia; LPL = lipoprotein lipase; LPLD = lipoprotein lipase deficiency     

Adipsic Diabetes Insipidus: A Review

Objective: Adipsic diabetes insipidus (ADI) is a rare disorder consisting of central diabetes insipidus (CDI) and a deficient or absent thirst response to hyperosmolality. Patients with ADI experience marked morbidity and mortality. Diagnosis and management of these patients is quite challenging, even in expert hands. In this review, we aim to provide an updated overview of this difficult clinical scenario.Methods: We conducted a PubMed search for articles related to ADI. The search terms “adipsia,” “adipsic,” “thirst,” and “diabetes insipidus” were used to identify relevant literature.Results: ADI has been described in only approximately 100 patients. This rarity has limited the quality and quantity of literature to case reports, case series, and expert opinion. Diagnosis focuses on confirmation of CDI followed by documenting subnormal or completely absent thirst in response to a hypertonic stimulus. Among the described patients with ADI, the majority experience morbidity (e.g., severe hypernatremia, sleep apnea, venous thromboembolism [VTE], and obesity) and an increased mortality risk. Management focuses on frequent reassessment of daily prescribed water intake with fixed antidiuretic therapy (desmopressin) and comorbidity screening.Conclusion: The complexity of patients with ADI provides a difficult challenge for clinicians. Prompt recognition of thirst disorders in patients with CDI should lead to appropriately regimented management strategies and can result in safe outpatient care for these unique patients.Abbreviations:ACoA = anterior communicating arteryADI = adipsic diabetes insipidusAVP = arginine vasopressinCDI = central diabetes insipidusDDAVP = desmopressinDI = diabetes insipidusSDB = sleep-disordered breathingVTE = venous thromboembolism     

The Classic and Nonclassic Concenital Adrenal Hyperplasias

Objective: The American Association of Clinical Endocrinologists Adrenal Scientific Committee has developed a series of articles to update members on the genetics of adrenal diseases.Methods: Case presentation, discussion of literature, table, and bullet point conclusions.Results: The congenital adrenal hyperplasia (CAH) syndromes are autosomal recessive defects in cortisol biosynthesis. The phenotype of each CAH patient depends on the defective enzyme and the severity of the defect. Clinical manifestations derive from both failure to synthesize hormones distal to the enzymatic block, as well as consequences from cortisol precursor accumulation proximal to the block, often with diversion to other biologically active steroids. The most common form of CAH is 21-hydroxylase deficiency, which occurs in the classic form in 1 in 16,000 newborns and in a milder or nonclassic form in at least 1 in 1,000 people.Conclusion: This article reviews the various forms of CAH and pitfalls in the diagnosis and treatment of these conditions.Abbreviations: 11OHD = 11-hydroxylase deficiency 17OHD = 17-hydroxylase deficiency 17OHP = 17-hydroxyprogesterone 21OHD = 21-hydroxylase deficiency 3βHSD = 3β-hydroxysteroid dehydrogenase CAH = congenital adrenal hyperplasia CST = cosyntropin stimulation test CYP17A1 = cytochrome P450 17A1 (steroid 17-hydroxylase/17,20-lyase) DHEAS = dehydroepiandrosterone sulfate DSD = disorder of sex development LCAH = lipoid congenital adrenal hyperplasia NBS = newborn screening NCAH = nonclassic CAH PCOS = polycystic ovary syndrome PORD = P450-oxidoreductase deficiency     

The Management of Hyperglycemia in Noncritically ill Hospitalized Patients Treated with Continuous Enteral or Parenteral Nutrition

Objective: Hyperglycemia is a common problem in hospitalized patients receiving artificial nutrition, and this development of hyperglycemia during parenteral nutrition therapy (PNT) and enteral nutrition therapy (ENT) increases the risks of hospital-related complications and mortality. This review aims to discuss the pathogenesis of hyperglycemia from artificial nutrition in the hospital, summarize current evidence on the treatment of hyperglycemia with insulin in these patients, and review current guidelines.Methods: A systematic literature review using PubMed and the Medical Subject Headings (MeSH) terms “hyperglycemia,” “enteral nutrition,” and “parenteral nutrition” were used to evaluate the current evidence available for treating noncritically ill patients with hyperglycemia who were receiving artificial nutrition.Results: The literature review showed that few randomized control trials exist regarding treatment of hyperglycemia in this cohort of patients, and the multiple retrospective evaluations that have addressed this topic provided varied results. In general, intravenous (IV) continuous insulin infusion offers the best glycemic control; however, this route of insulin administration is often burdensome for floor patients and their care teams. Administration of scheduled subcutaneous (SQ) insulin in patients on ENT or PNT is a safe and effective way to manage hyperglycemia, however limited data exist on an appropriate insulin regimen.Conclusion: Further prospective, randomized control trials are necessary to determine the optimal treatment of hyperglycemia for patients receiving ENT or PNT.Abbreviations: BG = blood glucose; CG = conventional glycemic control; ENT = enteral nutrition therapy; GIP = glucose-dependent insulinotropic polypeptide; GLP-1 = glucagon-like peptide 1; IG = intensive glycemic control; IV = intravenous; NPH = neutral protamine Hagedorn; PNT = parenteral nutrition therapy; SQ = subcutaneous; T2DM = type 2 diabetes mellitus; TDD = total daily dose; TPN = total parenteral nutrition     

American Association of Clinical Endocrinologists and American College of Endocrinology Disease State Clinical Review: A Neuroendocrine Approach to Patients With Traumatic Brain Injury

Objective: Traumatic brain injury (TBI) is now recognized as a major public health concern in the United States and is associated with substantial morbidity and mortality in both children and adults. Several lines of evidence indicate that TBI-induced hypopituitarism is not infrequent in TBI survivors and may contribute to the burden of illness in this population. The goal of this article is to review the published data and propose an approach for the neuroendocrine evaluation and management of these patients.Methods: To identify pertinent articles, electronic literature searches were conducted using the following keywords: “traumatic brain injury,” “pituitary,” “hypopituitarism,” “growth hormone deficiency,” “hypogonadism,” “hypoadrenalism,” and “hypothyroidism.” Relevant articles were identified and considered for inclusion in the present article.Results: TBI-induced hypopituitarism appears to be more common in patients with severe TBI. However, patients with mild TBI or those with repeated, sports-, or blast-related TBI are also at risk for hypopituitarism. Deficiencies of growth hormone and gonadotropins appear to be most common and have been associated with increased morbidity in this population. A systematic approach is advised in order to establish the presence of pituitary hormone deficiencies and implement appropriate replacement therapies.Conclusion: The presence of traumatic hypopituitarism should be considered during the acute phase as well as during the rehabilitation phase of patients with TBI. All patients with moderate to severe TBI require evaluation of pituitary function. In addition, symptomatic patients with mild TBI and impaired quality of life are at risk for hypopituitarism and should be offered neuroendocrine testing.Abbreviations: CBG = corticosteroid-binding globulin DI = diabetes insipidus GH = growth hormone IGF-1 = insulin-like growth factor 1 SIADH = syndrome of inappropriate antidiuretic hormone T₄ = thyroxine TBI = traumatic brain injury TSH = thyroid-stimulating hormone     

Insulin and endothelial function: A brief review

Background: In recent years, the novel effects of insulin beyond control of glucose metabolism have been appreciated, especially those that impact vascular function. A better understanding of insulin's protective interactions with the endothelium has provided clinicians with a justification for more aggressive use of insulin—not only to control glucose levels, but also to potentially reduce the progression of atherosclerosis and its pathogenic sequelae.Objective: In this brief review, we provide a snapshot of the available research and clinical findings signifying beneficial effects of insulin on the endothelium.Methods: We conducted a MEDLINE search of articles published in English from 1965 through 2007 using the search terms insulin, endothelium, and anti-inflammatory. Articles with a focus on “insulin resistance” per se were excluded from this review.Results: The literature search identified 200 articles that addressed the effects of insulin on endothelium and the interaction between insulin and the vasculature.Conclusions: In addition to mitigating hyperglycemic toxicity, insulin has multiple beneficial interactions with the endothelium in physiologic and disease states. The anti-inflammatory actions of insulin confer beneficial effects in preventing and minimizing morbidity and mortality due to atherosclerosis, especially in acute settings like myocardial infarction.     

Hypophosphatasia: Clinical Assessment and Management in the Adult Patient–A Narrative Review

Objective: To review literature and present a schematic approach to hypophosphatasia (HPP) evaluation and management applicable to practicing physicians to ease its recognition and diagnosis.Methods: Studies were obtained from online databases PubMed and MEDLINE using keyword ‘hypophosphatasia.’Results: HPP is a rare disease characterized by low serum alkaline phosphatase along with diverse musculoskeletal symptoms that mimic different disorders. To date, the prevalence of HPP and its impact on adults has been unrecognized. There is lack of evidence from larger and long-term studies examining the adult type of this condition.Conclusion: It is essential to increase awareness on the complexity of the pathophysiology and clinical features of HPP, which causes debilitating physical conditions that severely affects quality of life. A better comprehension of adult forms of HPP is essential to reduce a delay in diagnosis as well as ensure suitable management.Abbreviations: ALP = alkaline phosphatase; HPP = hypophosphatasia; PEA = phosphorethanolamine; PLP = pyridoxal-5-phosphate; PPi = inorganic pyrophosphate; TNSALP/TNAP = tissue-nonspecific alkaline phosphatase     

American Association of Clinical Endocrinologists,American College of Endocrinology Disease State Clinical Review: Clinical Relevance of Macroprolactin in the Absence or Presence of True Hyperprolactinemia

Objective: To review the current literature regarding the prevalence of macroprolactin (macroPRL) in hyperprolactinemic patients and determine recommendations for testing.Methods: An electronic United States National Library of Medicine PubMed search was conducted for search term “macroprolactin.” Only English-language articles were considered.Results: MacroPRL is an under-recognized cause of elevated prolactin (PRL) and is present in approximately 4% to 40% of hyperprolactinemic patients depending on the referral population. Clinical findings which could be due to hyperprolactinemia are the impetus for testing for PRL. Because of this there is significant overlap in the clinical presentation of patients with true hyperprolactinemia and those with macroPRL, differentiation cannot always be made on the basis of symptoms. A lack of recognition of the presence of macroPRL can lead to unnecessary laboratory investigations, imaging, and pharmacologic or surgical treatment.Conclusion: Until there is a commercially available PRL assay that is not subject to interference by macroPRL, clinicians should consider the possibility of macroPRL, especially if the clinical presentation, imaging findings, and/or response to therapy reveal inconsistenciesAbbreviations:DA = dopamine agonistGFC = gel filtration chromatographyIgG = immunoglobulin GmacroPRL = macroprolactinMMP3 = matrix metalloproteinase-3NS = nonsignificantPEG = polyethylene glycolPRL = prolactinRA = rheumatoid arthritisSLE = systemic lupus erythematosus     

Genetics of Primary Aldosteronism

Objective: The American Association of Clinical Endocrinologists Adrenal Scientific Committee has developed a series of articles to update members on the genetics of adrenal diseases.Methods: Case presentation, discussion of literature, table, and bullet point conclusions.Results: Primary aldosteronism (PA) is the most common form of secondary hypertension. Early detection, surveillance, and treatment of PA may mitigate future cardiovascular risk. The genetics of PA are rapidly evolving, and the consideration for genetic causes of PA are growing. Three inheritable forms of PA are now recognized: familial hyperaldosteronism type I (glucocorticoidremediable aldosteronism), familial hyperaldosteronism type II, and familial hyperaldosteronism type III. The recent discovery of familial hyperaldosteornism type III spurred a flurry of international and collaborative research that is identifying more genetic and molecular causes of PA that relate to mutations in membrane electrolyte transport channels of zona glomerulosa cells.Conclusion: This article reviews the various genetic forms of PA, including a focus on the molecular mechanisms involved, diagnosis, and treatment.Abbreviations: ACTH = adrenocorticotropic hormone ARR = aldosterone to renin ratio FH-I = familial hyperaldosteronism type I FH-II = familial hyperaldosteronism type II FH-III = familial hyperaldosteronism type III GRA = glucocorticoidremediable aldosteronism PA = primary aldosteronism PRA = plasma renin activity     

Metformin: Nonglycemic Effects and Potential Novel Indications

Objective: Metformin is the most commonly prescribed drug for the treatment of type 2 diabetes because of its apparent robust effects in reducing cardiovascular risk. This review examines the current literature regarding the nonglycemic effects and potential novel indications for metformin.Methods: Review of the literature, with a focus on metformin use in Stage 3 chronic kidney disease (CKD-3) and heart failure (HF).Results: The United Kingdom Prospective Diabetes Study suggests that metformin reduces the risk of myocardial infarction, and more recent retrospective studies have shown an association between metformin use and a reduction in stroke, atrial fibrillation and all-cause mortality. The mechanism(s) explaining these putative benefits are not clear but may involve decreased energy intake (with attendant weight loss), improvement in lipids, and lowering of blood pressure; a literature review suggests that metformin lowers blood pressure when it is elevated, but not when it is normal. Metformin appears to be safe when given to patients with CKD-3. In addition, there is evidence that individuals with CKD-3, who are at increased cardiovascular risk, stand to benefit from metformin therapy. Lactic acidosis is an extremely remote and probably avoidable risk; measurement of plasma metformin levels and more frequent monitoring of renal function may be useful in selected patients with CKD-3 who are treated with metformin. Finally, there is evidence that metformin is safe in patients with HF; metformin therapy is associated with a reduction in newly incident HF and in HF mortality.Conclusion: Metformin has a dominant position in the treatment of type 2 diabetes that is deserved due to its favorable and robust effects on cardiovascular risk.Abbreviations:AMP = adenosine monophosphateBP = blood pressureCKD = chronic kidney diseaseCKD-3 = Stage 3 CKDeGFR = estimated glomerular filtration rateHDL = high-density lipoproteinHF = heart failureMAP = mean arterial pressuremVO₂ = myocardial oxygen consumptionT2DM = type 2 diabetes mellitusUKPDS = United Kingdom Prospective Diabetes Study     

Hirsutism: Diagnosis and management

Background:Hirsutism is defined as excess hair growth in androgen-dependent areas of the body in women.Objective: This article provides an updated review of hirsutism, focusing on the etiologies, clinical features, approach to diagnostic evaluation, and treatment options.Methods: The PubMed database was searched for English-language articles published from 1981 to the present, using the terms hirsutism, polycystic ovarian syndrome, congenital adrenal hyperplasia, hirsutism diagnosis, and hirsutism treatment. Reference lists from review articles on hirsutism during this time period were also examined.Results: While there are many causes of hirsutism, the majority of patients have a benign process that may be idiopathic. In some circumstances, hirsutism is a sign of functional ovarian hyperandrogenism or congenital adrenal hyperplasia. Even more rarely, it is the presenting sign of an internal malignancy.Conclusions: Hirsutism clinically presents in women as excessive hair growth in androgen-dependent areas. It is a particularly important diagnosis to make, because it often significantly affects a woman's perception of her femininity and less commonly can be a sign of an underlying malignancy or a cutaneous manifestation of a condition with significant cardiovascular or other morbidity. A variety of treatments exist to help minimize the appearance of unwanted hair.     

Pheochromocytoma and Paraganglioma

Objective: Pheochromocytomas (PHEOs) and paragangliomas (PGLs) are neural crest cell tumors associated with catecholamine production and assessed by a metanephrine/methoxytyramine measurement. This review summarizes the genetics of these tumors.Methods: Case presentation, review of the relevant literature, and bullet point conclusions.Results: Genetic research over the past 10 years has led to a better understanding of the pathogenesis of these tumors, currently associated with 20 susceptibility genes (both somatic and germ-line mutations). Although most of these genes can be divided into two clusters (clusters 1 and 2), recent data suggest that all mutations converge on the hypoxia-inducible factor signaling pathway. Most of the susceptibility genes are well characterized and associated with specific clinical presentations, including biochemical phenotype, tumor location and behavior, as well as neoplasms or similar characteristics. Correct and early detection of hereditary PHEO/PGL is paramount, as early diagnosis leads to improved and focused treatment, along with better outcomes. However, missed or delayed diagnosis of hereditary PHEO/PGL forestalls proper treatment and results in multiple, recurrent, or metastatic tumors and avoidable complications in some patients.Conclusion: Early diagnosis allows prompt screening for potentially lethal cancers associated with specific gene mutations and makes genetic testing more readily available to first-degree and other relatives of an index patient. Thus, understanding the genetics of these tumors is an essential part of endocrinology.Abbreviations: HIF2A = hypoxia-inducible factor 2α MAX = Myc-associated factor X MEN2 = multiple endocrine neoplasia type 2 NF1 = neurofibromatosis type 1 PGL = paraganglioma PHEO = pheochromocytoma SDHAF2 = succinate dehydrogenase complex assemble factor 2 TMEM127 = transmembrane protein 127 VHL = von Hippel-Lindau     

Consensus Statement by the American Association of Clinical Endocrinologists and American College of Endocrinology on the Quality of DXA Scans and Reports

Objective: High-quality dual-energy X-ray absorptiometry (DXA) scans are necessary for accurate diagnosis of osteoporosis and monitoring of therapy; however, DXA scan reports may contain errors that cause confusion about diagnosis and treatment. This American Association of Clinical Endocrinologists/American College of Endocrinology consensus statement was generated to draw attention to many common technical problems affecting DXA report conclusions and provide guidance on how to address them to ensure that patients receive appropriate osteoporosis care.Methods: The DXA Writing Committee developed a consensus based on discussion and evaluation of available literature related to osteoporosis and osteodensitometry.Results: Technical errors may include errors in scan acquisition and/or analysis, leading to incorrect diagnosis and reporting of change over time. Although the International Society for Clinical Densitometry advocates training for technologists and medical interpreters to help eliminate these problems, many lack skill in this technology. Suspicion that reports are wrong arises when clinical history is not compatible with scan interpretation (e.g., dramatic increase/decrease in a short period of time; declines in previously stable bone density after years of treatment), when different scanners are used, or when inconsistent anatomic sites are used for monitoring the response to therapy. Understanding the concept of least significant change will minimize erroneous conclusions about changes in bone density.Conclusion: Clinicians must develop the skills to differentiate technical problems, which confound reports, from real biological changes. We recommend that clinicians review actual scan images and data, instead of relying solely on the impression of the report, to pinpoint errors and accurately interpret DXA scan images.Abbreviations: AACE = American Association of Clinical Endocrinologists; BMC = bone mineral content; BMD = bone mineral density; DXA = dual-energy X-ray absorptiometry; ISCD = International Society for Clinical Densitometry; LSC = least significant change; TBS = trabecular bone score; WHO = World Health Organization     

Nasal Glucagon Delivery is More Successful than Injectable Delivery: A Simulated Severe Hypoglycemia Rescue

Objective: A severe hypoglycemia (SH) episode is an acute, high-stress moment for the caregivers of persons with diabetes (PWD). We compared the success rates of nasal glucagon (NG) and injectable glucagon (IG) administration for PWD-trained and untrained users in treating simulated SH episodes.Methods: Thirty-two PWD-trained users and 33 untrained users administered NG and IG to high-fidelity manikins simulating treatment of an SH emergency. Simulation rooms resembled common locations with typical diabetic supplies and stressor elements mimicking real-life SH environments. Success rate and time to administer glucagon were measured.Results: Of all the PWD-trained and untrained users, 58/64 (90.6%) could successfully deliver NG, while 5/63 (7.9%) could successfully deliver IG. For NG simulations, 28/31 (90.3%) PWD-trained users and 30/33 (90.9%) untrained users could successfully administer the dose (mean time 47.3 seconds and 44.5 seconds, respectively). For IG simulations, 5/32 (15.6%) PWD-trained users successfully injected IG (mean time 81.8 seconds), whereas none (0/31 [0%]) of the untrained users were successful. Reasons for unsuccessful administration of NG included oral administration and incomplete pushing of the device plunger. For IG, inability to perform reconstitution steps, partial dose delivery, and injection at an inappropriate site were the causes for failure.Conclusion: With or without training, the success rate for administering NG was 90.6%, whereas it was only 7.9% for IG. NG was easily and quickly administered even by untrained users, whereas training was necessary for successful administration of IG. NG may expand the community of caregivers who can help PWD during an SH episode.Abbreviations: IG = injectable glucagon; NG = nasal glucagon; PWD = person with diabetes; SH = severe hypoglycemia; T1D = type 1 diabetes; T2D = type 2 diabetes     

Imaging Localization and Surgical Approach in the Management of Ectopic Parathyroid Adenomas

Objective: (1) Review the anatomy and epidemiology of ectopic parathyroid adenomas (EPAs), (2) summarize the role of relevant imaging modalities in the localization of EPAs, and (3) characterize surgical approaches for various ectopic locations.Methods: Literature review of published English-language articles from 1995 through August 2017.Results: Summary of the literature indicates that the prevalence of EPA is approximately 20% in unexplored patients with primary hyperparathyroidism, but it is as high as 66% in re-operative patients. EPAs may be located anywhere from the carotid bifurcation to the aorto-pulmonary window. Ultrasound has limited accuracy in identifying EPAs except near the thyroid and thyrothymic ligament and requires expert experience from the user. Among dual-phase ^99mTc sestamibi scintigraphy techniques, hybrid imaging with both single-photon emission computed tomography (SPECT) and computed tomography (CT) (SPECT/CT) is superior to planar scintigraphy or SPECT alone at localizing EPAs. Four-dimensional computed tomography (4DCT) precisely delineates important anatomic relationships and is highly sensitive in localizing EPAs. Although 4DCT requires radiation, intravenous iodinated contrast, and reader experience, it is well-equipped to detect lesions at various ectopic sites and guide the surgical approach. EPAs frequently require alternative surgical approaches. Re-operative parathyroidectomy may be attempted in patients having previously undergone bilateral neck exploration by an experienced surgeon once the lesion is colocalized by 2 repeat imaging modalities. Removal of nonlocalized disease requires a careful and systematic exploration of superior and inferior gland locations.Conclusion: EPAs pose challenges during both localization and surgical removal. High-volume experience and multidisciplinary care are necessary for optimal outcomes.Abbreviations: CT = computed tomography; 4DCT = 4-dimensional CT; EPA = ectopic parathyroid adenoma; EPG = ectopic parathyroid gland; PHPT = primary hyperparathyroidism; RLN = recurrent laryngeal nerve; SPECT = single-photon emission computed tomography; TE = tracheo-esophageal     

Integrated Insulin Pump and Continuous Glucose Monitoring Technology in Diabetes Care Today: A Perspective of Real-Life Experience With the Minimed™ 670G Hybrid Closed-Loop System

Objective: Intensive glucose management with insulin pump and continuous glucose monitoring therapy in insulin-treated patients with diabetes poses many challenges in all aspects of daily life. Automated insulin delivery (AID) is the ultimate goal of insulin replacement therapy to reduce the burden of managing this condition. Many systems are being tested in the clinical research setting, and one hybrid closed-loop (HCL) system has received Food and Drug Administration (FDA) approval for use in type 1 diabetes patients above the age of 14 years.Methods: Literature review and clinical practice experience from the Diabetes and Technology Program at an academic medical center.Results: This review outlines recent advances in AID systems, focusing on the FDA-approved MiniMed™ 670G HCL system and the real-life experience 1-year post-release in an academic medical center with over 60 patients on this system. The unique challenges of adapting to this new system outside the clinical trial setting are highlighted, and a training protocol designed specifically for the onboarding of first-time users is described.Conclusion: HCL insulin therapy offers several advantages, at the same time posing unique challenges to the user. Systematic training of patients with diabetes transitioning to this system is essential for retention and success of use.Abbreviations: AID = automated insulin delivery; CGM = continuous glucose monitoring; FDA = Food and Drug Administration; HbA1c = glycated hemoglobin; HCL = hybrid closed-loop; ICR = insulin to carbohydrate ratio; SAP = sensor augmented pump; T1DM = type 1 diabetes