Novel Formative Approach of the ESAP-ITE Provides Strong Predictive Value for ABIM Certification Outcomes.

BACKGROUND: The Endocrine Self-Assessment Program In-Training Examination (ESAP-ITE) has the novel formative approach of allowing open access to all questions and answers after secure examination administration is complete, resulting in the creation of an entirely new in-training examination annually. OBJECTIVE: To determine whether scores on the novel ESAP-ITE predict pass/fail outcomes on the American Board of Internal Medicine Endocrinology, Diabetes, and Metabolism Certification Examination (ABIM-ECE). METHODS: All endocrine fellows-in-training who took the ESAP-ITE between 2016 and 2019 and then subsequently attempted the ABIM-ECE within the same calendar year were included (n = 982). Primary analyses used the ESAP-ITE score from the final year of fellowship training. Covariates included sex, age on date of ABIM-ECE, medical school country, fellowship program region, pass/fail outcomes on the ABIM Internal Medicine Certification Examination, and ESAP-ITE score. All variables were analyzed using multivariable logistic regression. RESULTS: ESAP-ITE score (P < 0.001), ABIM Internal Medicine Certification Examination outcome (P < 0.001), and age (P = 0.005) were each significant predictors of passing the ABIM-ECE on the first attempt. ESAP-ITE score was the strongest predictor of passing the ABIM-ECE, and this relationship was such that a score of 75% correct yielded a 97% probability of passing the ABIM-ECE, whereas a score of 50% correct generated only a 70% probability of doing so. Sex, fellowship program region, and medical school country were not significant predictors of ABIM-ECE outcomes. CONCLUSIONS: In addition to serving as an important learning instrument for endocrine fellowship programs, ESAP-ITE is a robust predictive tool for pass/fail outcomes on the ABIM-ECE.

Gestational Primary Hyperparathyroidism Due to Ectopic Parathyroid Adenoma: Case Report and Literature Review.

Gestational primary hyperparathyroidism (GPHPT) is a rare condition with fewer than 200 cases reported. We present the case of a 21-year-old woman who presented at 10 weeks' gestation with severe hypercalcemia. Laboratory investigation was consistent with primary hyperparathyroidism. Neck ultrasound did not reveal any parathyroid enlargement. Due to the persistence of severe hypercalcemia, she was treated with 4 weeks of cinacalcet therapy, which was poorly tolerated due to nausea and vomiting. At 14 weeks' gestation, she underwent neck exploration with right lower, left upper, and partial right upper parathyroid gland excision. Intra- and postoperative parathyroid hormone (PTH) and calcium levels remained elevated. After a thorough discussion of risks/benefits, the patient requested further treatment. A parathyroid sestamibi scan (PSS) revealed an ectopic adenoma in the left mediastinum. The adenoma was removed via video-assisted thorascopic parathyroidectomy with intraoperative PTH declining to nearly undetectable levels. She ultimately delivered a physically and developmentally normal infant at 37 weeks' gestation. Appropriate treatment of severe GPHPT may prevent the maternal and fetal complications of hypercalcemia. This case, in which cinacalcet therapy and PSS were used, adds to the body of literature regarding treatment of severe GPHPT.

Medical Management of Osteoporosis for Elective Spine Surgery.

Over 50 million Americans have low bone mass. Poor bone quality is known to complicate spinal fusion surgery, which relies on strong bony purchase to be effective. Unfortunately, many spine surgeons do not perform routine workups for either osteoporosis or osteomalacia. Effective screening and risk factor assessment can allow for appropriate medical management of osteoporosis in the perioperative setting, improving outcomes. Medical management can be grouped into several different categories: vitamins and minerals, bisphosphonates, recombinant parathyroid hormone, estrogen replacement or modification, inhibitors of receptor activator of nuclear factor κ-B ligand (RANKL), and calcitonin. Calcium and vitamin D supplements are the least expensive to prescribe, with minimal side effects and promising animal studies, and thus should be provided to most osteoporotic patients. Recombinant parathyroid hormone can also be considered, as clinical studies have demonstrated impressive results in spine fusion patients. Bisphosphonates, estrogen therapy or selective estrogen receptor modulators, and calcitonin should all be avoided in this patient population given unproven benefit and potentially harmful side-effect profiles. Denosumab is potentially an option, but may not be first line given the general lack of supporting data for its use in perioperative management of spine surgery patients.

Electrolyte disorders associated with cancer.

Patients with malignancies commonly experience abnormalities in serum electrolytes, including hyponatremia, hypokalemia, hyperkalemia, hypophosphatemia, and hypercalcemia. In many cases, the causes of these electolyte disturbances are due to common etiologies not unique to the underlying cancer. However, at other times, these electrolyte disorders signal the presence of paraneoplastic processes and portend a poor prognosis. Furthermore, the development of these electrolyte abnormalities may be associated with symptoms that can negatively affect quality of life and may prevent certain chemotherapeutic regimens. Thus, prompt recognition of these disorders and corrective therapy is critical in the care of the patient with cancer.

Osteoporosis treatment and prevention for postmenopausal women: current and future therapeutic options.

Osteoporosis, a "silent disease," is often unrecognized until fracture. Lifestyle modification with nutritional counseling is recommended during menopausal transition. Bone density testing is recommended for women aged 65 years and older, younger postmenopausal women with risk factors, or to follow therapy. Bisphosphonates treat osteoporosis (prevent bone resorption). Raloxifene and hormone therapy prevent bone loss and fracture, with extraskeletal benefits. Denosumab treats osteoporosis, although bone effects reverse rapidly. Teriparatide (anabolic therapy) is considered for women at high risk of fracture. Bazedoxifene with conjugated estrogens, novel delivery of teriparatide, new parathyroid hormone proteins, anti-sclerostin antibodies, cathepsin K inhibitors, and stem cell therapies are in testing.

Onco-nephrology: the pathophysiology and treatment of malignancy-associated hypercalcemia.

Hypercalcemia complicates the course of 10%-30% of all patients with malignancies and can be a sign of very poor prognosis and advanced malignancy. Prompt recognition of the nonspecific signs and symptoms of hypercalcemia and institution of therapy can be lifesaving, affording the opportunity to address the underlying etiology. The mechanisms of malignancy-associated hypercalcemia generally fall into three categories: humoral hypercalcemia due to secreted factors (such as parathyroid-related hormone), local osteolysis due to tumor invasion of bone, and absorptive hypercalcemia due to excess vitamin D produced by malignancies. The mainstays of therapy for hypercalcemia are aggressive intravenous volume expansion with saline, bisphosphonate therapy, and perhaps loop diuretics. Adjunctive therapy may include calcitonin and corticosteroids. In refractory cases, gallium nitrate and perhaps denosumab are alternatives. In patients presenting with severe AKI, hemodialysis with a low-calcium bath can be effective. In most cases, therapy normalizes calcium levels and allows for palliation or curative therapy of the malignancy.

Treatment of postmenopausal osteoporosis in a patient with celiac disease.

BACKGROUND: A 62-year-old postmenopausal woman with a family history of breast cancer, mild gastroesophageal reflux disease, iron-deficient anemia and declining BMD was seen in a specialist center for the evaluation and management of osteoporosis. INVESTIGATIONS: Analysis of tissue transglutaminase IgA, endoscopic biopsy, serial BMD scans, FRAX calculation of osteoporotic fracture risk, Gail model calculation of breast cancer risk, assessment of blood vitamin D concentration and secondary evaluation for osteoporosis. DIAGNOSIS: Osteoporosis, persistent after 12 years of hormone replacement therapy, and celiac disease. MANAGEMENT: The patient was initially treated for bone loss with postmenopausal hormone replacement therapy. DXA analyses showed a continued decline in BMD despite adequate replacement of calcium and vitamin D levels and withdrawal of gluten from the patient's diet. An oral bisphosphonate was recommended with plans to reassess BMD after 1 year.

Phosphaturic mesenchymal tumor diagnosed by fine-needle aspiration and core biopsy: a case report and review of literature.

Oncogenic (tumor-induced) osteomalacia is a rare paraneoplastic syndrome of phosphate wasting that is frequently associated with phosphaturic mesenchymal tumor (PMT). As the cytologic features of this tumor apparently have not been reported, we describe the fine-needle aspiration (FNA) findings for PMT that arose from the gluteal soft tissue in a patient with hypophosphatemia and multiple fractures secondary to osteomalacia. Smears from the computerized tomography (CT)-guided FNA showed groups of spindle cells having elongated nuclei, fine to moderately coarsely granular chromatin, inconspicuous nucleoli, and delicate cytoplasm. Marked nuclear atypia, mitotic figures, and necrosis were absent. The differential diagnosis included a variety of benign and malignant spindle cell neoplasms such as monophasic synovial sarcoma, leiomyoma, peripheral nerve sheath tumor, fibrosarcoma, and, less likely, metastatic melanoma and sarcomatoid carcinoma. The bland-appearing cytologic features of a spindle cell tumor in a patient with osteomalacia should suggest the diagnosis of PMT.

Combination therapy for treatment of osteoporosis: A review.

Combination therapy for osteoporosis has been tested in small trials of short duration with various combinations. Pertinent human and animal randomized clinical trial data were identified through Medline and reviewed with a focus on the risks and benefits of different types of combination therapies. Improvements in bone density were found in some, but not all, combinations. There are no large trials of adequate length or numbers to determine fracture efficacy. Consider combination therapy if monotherapy is unsuccessful, if there is an added nonskeletal benefit to the proposed combination or as sequential treatment with an anabolic agent followed by an antiresorptive agent. Although combination therapy, in general, has limitations based on cost, concern about potential oversuppression of bone, and lack of long-term safety and fracture efficacy, selected patients may benefit.

The regulation of FSHbeta transcription by gonadal steroids: testosterone and estradiol modulation of the activin intracellular signaling pathway.

Recent reports suggest that androgens increase FSHbeta transcription directly via the androgen receptor and by modulating activin signaling. Estrogens may also regulate FSHbeta transcription in part through the activin system. Activin signaling can be regulated extracellularly via activin, inhibin, or follistatin (FS) or intracellularly via the Smad proteins. We determined the effects of androgen and estrogen on FSHbeta primary transcript (PT) concentrations in male and female rats, and we correlated those changes with pituitary: activin betaB mRNA, FS mRNA, the mRNAs for Smads2, -3, -4, and -7, and the phosphorylation (p) status of Smad2 and -3 proteins. In males, testosterone (T) increased FSHbeta PT two- to threefold between 3 and 24 h and was correlated with reduced FS mRNA, transient increases in Smad2, -4, and -7 mRNAs, and a six- to 10-fold increase in pSmad2, and activin betaB mRNA was unchanged. In females, T also increased FSHbeta PT twofold and pSmad2 threefold but had no effect on activin betaB, FS, or the Smad mRNAs. Androgen also increased Smad2 phosphorylation in gonadotrope-derived alphaT3 cells. In contrast, estradiol had no effect on FSHbeta PT but transiently increased activin betaB mRNA and suppressed FS mRNA before increasing FS mRNA at 24 h and increased Smads2, -3, and -7 mRNAs and pSmad2 threefold. In conclusion, T acts on the pituitary to increase FSHbeta PT in both sexes and modulates FS mRNA, Smad mRNAs, and/or Smad2 phosphorylation. These findings suggest that T regulates FSHbeta transcription, in part, through modulation of various components of the activin-signaling system.

Stimulation of FSHbeta transcription by blockade of endogenous pituitary follistatin production: Efficacy of adenoviral-delivered antisense RNA in the rat.

This study investigated FSHbeta transcriptional responses to the suppression of endogenous follistatin (FST) production using FST antisense RNA (FST-AS) expressing adenovirus constructs in female rat pituitary cells in vitro. Adenoviral delivery systems were characterized and optimized using an adenovirus-green fluorescent protein construct, and maximal infection (85-90% of cells) was seen 48 h post adenovirus treatment. A 424 bp fragment, which included the translational start site and exons 1-3 of the rat FST gene, was subcloned in the reverse orientation into an adenovirus vector. Construct efficacy was tested using cultured rat pituitary cells infected with the adenovirus-FST-AS construct. Infection with adenovirus-FST-AS increased FST-AS mRNA expression in a dose-dependent manner, reduced FST protein expression to undetectable levels, and stimulated increases in FSHbeta primary transcript and FSH secretion. Treatment with testosterone alone stimulated FSHbeta primary transcript and FSH release, and responses were doubled in the presence of adenovirus- FST-AS. These results demonstrate the effectiveness of adenovirus FST-AS in suppressing pituitary FST protein expression and enhancing FSH biological responses at the transcriptional level. Thus, the FST-deficient rat gonadotrope cell is a model that allows for the investigation of factors regulating FSHbeta expression, which might otherwise involve the autocrine/paracrine actions of FST.

Pituitary adenylate cyclase activating polypeptide messenger RNA in the paraventricular nucleus and anterior pituitary during the rat estrous cycle.

The neuropeptide pituitary adenylate cyclase activating polypeptide (ADCYAP 1, or PACAP) has been demonstrated to enhance gonadotropin-releasing hormone (GnRH)-induced gonadotropin secretion and regulate gonadotropin subunit gene expression in cultures of anterior pituitary cells. In the present study, we used in situ hybridization and real-time polymerase chain reaction to examine the expression of Pacap mRNA within the paraventricular nucleus (PVN) and anterior pituitary throughout the estrous cycle of the rat. Levels of luteinizing hormone in serum and pituitary gonadotropin subunit mRNAs were evaluated and displayed cyclic fluctuations similar to those reported previously. Pacap mRNA expression in the PVN and pituitary varied significantly during the estrous cycle, with the greatest changes occurring on the day of proestrus. Pacap mRNA levels in the PVN declined significantly on the morning of diestrus. During proestrus, PVN Pacap mRNA levels significantly increased 3 h before the gonadotropin surge and then declined. Pituitary expression of Pacap mRNA also varied on the afternoon of proestrus with a moderate decline at the time of the gonadotropin surge and a significant increase later in the evening. Expression of the mRNA species encoding the 288 amino acid form of follistatin increased significantly following the rise in pituitary Pacap mRNA, at the termination of the secondary surge in follicle-stimulating hormone beta (Fshb) gene expression. These results suggest that PACAP is involved in events before and following the gonadotropin surge, perhaps through increased gonadotroph sensitivity to GnRH and suppression of Fshb subunit expression through increased follistatin, as previously observed in vitro.

Pituitary follistatin gene expression in female rats: evidence that inhibin regulates transcription.

Follistatin (FS), along with the members of the transforming growth factor beta family activin and inhibin, are important regulators of FSH secretion and messenger RNA production. While activin and inhibin appear to function as tonic modulators of FSH (stimulatory and inhibitory, respectively), dynamic changes in FS are noted through the estrous cycle and under varying physiological experimental paradigms. This suggests that FS is a major contributor to the precisely coordinated secretion of FSH that maintains reproductive function. The aim of this study was to investigate changes in FS, in particular the early (<12 h) rise observed after ovariectomy (OVX), and to determine whether these changes were as a consequence of variations in gene transcription rates. FS primary transcript (PT) and mRNA were found to increase 3-fold 12 h post-OVX, indicating increased gene transcription during this time period. Replacement with estradiol and/or blockade of GnRH had only modest effects on FS PT concentration. Inhibin immunoneutralization of intact rats resulted in a 3-fold increase in FS PT 12 h after administration of inhibin alpha antisera. Significant increases in FS mRNA at both 2 and 12 h also suggested that inhibin also may have effects on message stability. After administration of recombinant human inhibin A, there was a prompt decline in both FS PT and mRNA. These results indicate that inhibin is a major regulator of FS, both by transcriptional and nontranscriptional mechanisms.

Regulation of luteinizing hormone-beta and follicle-stimulating hormone (FSH)-beta gene transcription by androgens: testosterone directly stimulates FSH-beta transcription independent from its role on follistatin gene expression.

The gonadotropin beta-subunit mRNAs are differentially regulated by androgens. Testosterone (T) suppresses LH-beta and increases FSH-beta. We aimed to determine whether androgens regulate LH-beta and FSH-beta transcription [as measured by changes in primary transcript (PT)] and to determine whether androgens act directly on FSH-beta or via the intrapituitary activin/follistatin (FS) system. In castrate + GnRH antagonist-treated rats, T increased FSH-beta PT between 3 and 48 h. In contrast, T suppressed LH-beta PT. The increases in FSH-beta mRNA and PT were associated with reduced FS mRNA. Activin betaB mRNA was modestly suppressed. The increase in FSH-beta PT after T was androgen specific. Both T and dihydrotestosterone (DHT) increased FSH-beta PT 2-fold and decreased both FS and betaB mRNA. Estradiol suppressed FSH-beta PT 3-fold and had no effect on FS or betaB mRNAs. LH-beta PT was suppressed by DHT. To determine whether T stimulation of FSH-beta PT reflected a decrease in pituitary FS, we gave androgen in the presence of exogenous FS in vitro. T and DHT increased FSH-beta PT 2- to 3-fold. FS alone decreased FSH-beta PT 40% but did not diminish the increase FSH-beta PT in response to T. T, DHT, and FS did not affect FS mRNA, betaB mRNA, or LH-beta PT. In conclusion, androgens acting directly on the pituitary increase FSH-beta and decrease LH-beta transcription. The increase in FSH-beta PT in response to T was androgen specific and occurs in the presence of excess FS, suggesting that T stimulates FSH-beta transcription independently of modulation of FS.

Differential expression of the pituitary gonadotropin subunit genes during male rat sexual maturation: reciprocal relationship between hypothalamic pituitary adenylate cyclase-activating polypeptide and follicle-stimulating hormone beta expression.

The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) has been shown to differentially regulate the expression of the gonadotropin subunit genes in cultures of rat pituitary cells. PACAP is expressed within the hypothalamus, and concentrations of PACAP are 2- to 4-fold higher in the portal circulation than in the general circulation. Therefore, PACAP is a candidate regulator of pituitary function. In the present study, we examined the expression of PACAP mRNA within the paraventricular nucleus (PVN) during maturation (Days 20-60) in the male rat and compared this expression to the levels of the gonadotropin subunits, follistatin, and GnRH-receptor mRNAs within the anterior pituitary. Serum concentrations of FSH and LH confirm the established maturational pattern of divergent secretion of LH and FSH. Northern analysis of the gonadotropin subunit mRNAs revealed that FSHbeta expression parallels FSH secretion whereas LHbeta mRNA concentrations do not change during development. Expression of the GnRH receptor in the pituitary parallels that of FSHbeta. In situ hybridization revealed a developmental pattern of PACAP mRNA within the PVN that is reciprocal to that of FSHbeta. Competitive reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of total pituitary follistatin mRNA revealed no significant changes; however, semiquantitative RT-PCR analyses revealed the presence of two follistatin mRNA species, one of which, corresponding to follistatin-288, was developmentally regulated. These studies identified a reciprocal relationship between PVN PACAP and FSHbeta gene expression in maturing rats. We propose that PACAP contributes to the selective regulation of FSHbeta expression during maturation in the male rat, perhaps via regulation of follistatin.

GnRH pulse frequency modulation of gonadotropin subunit gene transcription in normal gonadotropes-assessment by primary transcript assay provides evidence for roles of GnRH and follistatin.

We examined the time course of action of GnRH pulse frequency on gonadotropin subunit gene transcription and assessed the roles of GnRH, follistatin (FS), and activin on differential transcription of the LHbeta and FSHbeta genes. GnRH-deficient male rats were pulsed with 25 ng GnRH either every 30 min (fast frequency) or every 240 min (slow frequency) for 1-24 h. Both GnRH frequencies increased alpha primary transcript (PT) 5-fold within 6 h, but only fast frequency GnRH increased alpha mRNA. Only fast frequency GnRH pulses affected LHbeta PT, resulting in 6- to 9-fold increases between 1-24 h. Fast frequency GnRH pulses transiently increased FSHbeta PT at 1 and 6 h (4- and 2-fold, respectively); but by 24 h FSHbeta PT had returned to control levels and was correlated to a 5- to 9-fold increase in FS mRNA. In contrast, slow GnRH pulses increased FSHbeta PT 3- and 6-fold at 8 and 24 h, respectively, which was correlated with a decline in FS mRNA. Activin mRNA did not change significantly after either GnRH frequency, but tended to fall after fast pulses. To test whether activin was required for the effects of GnRH on FSHbeta transcription, rats were treated with GnRH pulses every 240 min for 8 h +/- FS. FS treatment alone markedly decreased basal FSHbeta PT. GnRH in the presence of FS increased FSHbeta PT 8-fold but did not restore FSHbeta transcription to control or GnRH alone values. In summary, whereas alpha-subunit transcription is independent of frequency, an increase in alpha mRNA requires fast frequency GnRH pulses. Fast frequency GnRH pulses increased both LHbeta and FSHbeta transcription, but the response of FSHbeta was transient. The sustained rise in FSHbeta transcription and mRNA expression required slow frequency GnRH pulses and was correlated to low FS mRNA. Neutralization of pituitary activin by exogenous FS markedly reduced basal FSHbeta PT and mRNA but did not prevent the stimulation of FSHbeta transcription by slow frequency GnRH pulses. These studies suggest that the frequency regulation of FSHbeta transcription involves both direct actions of GnRH and indirect effects, via changes in pituitary FS expression.

Evidence that PACAP and GnRH down-regulate follicle-stimulating hormone-beta mRNA levels by stimulating follistatin gene expression: effects on folliculostellate cells, gonadotrophs and LbetaT2 gonadotroph cells.

Pituitary adenylate cyclase-activating polypeptide (PACAP) stimulates alpha-subunit transcription and lengthens LH-beta mRNA transcripts, but reduces FSH-beta mRNA levels in rat pituitary cell cultures. PACAP also stimulates follistatin transcription, an effect which may explain the decrease in FSH-beta mRNA. To begin to investigate the cells in which PACAP activates the follistatin gene, quantitative in situ hybridization for follistatin mRNA combined with immunostaining for LHbeta and S100 protein was performed. In control cultures, follistatin mRNA was expressed in 70% of gonadotrophs and in 47% of folliculostellate cells (S-100+). PACAP increased (P<0.001) both the number of follistatin-expressing cells as well as the number of grains per cell in both gonadotrophs and folliculostellate cells, while GnRH only affected (P=0.01) gonadotrophs. Follistatin and FSH-beta gene expression in rat pituitary cultures were also measured by competitive quantitative RT-PCR and northern analysis, respectively. Both PACAP and GnRH increased (P<0.05) follistatin gene expression and suppressed (P<0.05) FSH-beta mRNA, and the effect of PACAP together with GnRH on follistatin exceeded that of GnRH alone. PACAP regulation of follistatin and FSH-beta gene expression was studied further in LbetaT2 cells that were found to express receptors for the specific PACAP receptor, PAC(1). Follistatin mRNA was undetectable in cultures exposed to control media, or stimulated with PACAP, GnRH or rh-activin-A. In contrast to the results in primary pituitary cultures, PACAP increased FSH-beta mRNA in these follistatin-deficient cells. Moreover, using transient transfection, PACAP stimulated transcription of ovine-FSH-beta-luciferase. GnRH likewise increased FSH-beta mRNA and stimulated FSH-beta gene transcription in LbetaT2 cells. Activin-A increased FSH-beta gene expression dose-dependently, and activin induction of FSH-beta mRNA was blocked completely by 3-fold excess follistatin. These results indicate that PACAP stimulates follistatin gene expression in both gonadotrophs and folliculostellate cells, and provide further evidence that follistatin is required for PACAP or continuous GnRH to down-regulate FSH-beta mRNA. These experiments suggest a mechanism by which PACAP influences FSH production selectively by an autocrine effect on gonadotrophs and by a paracrine mechanism through folliculostellate cells that involves follistatin.