bluuebunny/crossref_metadata_2025_split huggingface dataset:
8446 Thermoneutral Housing has Limited Effects on Social Isolation-Induced Bone Loss in Male C57BL/6J Mice
Authors: Mountain R , Langlais A , Lary C , Motyl K J 
Published: October 2024

Abstract
Disclosure: R. Mountain: None. A. Langlais: None. C. Lary: None. K.J. Motyl: None.
Social isolation stress has numerous known negative health effects, including increased risk for cardiovascular disease, dementia, as well as overall mortality. The impacts of social isolation on skeletal health, however, have not been thoroughly investigated. We previously found that four weeks of social isolation through single housing led to a significant reduction in trabecular and cortical bone in male, but not female, mice. In addition to evidence of reduced bone remodeling, we found a significant elevation of Pdk4 and reduced brown adipocyte and lipid droplet size in the brown fat of isolated male mice, suggesting increased brown fat activation and thermal stress. Single housing at room temperature (∼20-25°C)—below the thermoneutral range of mice (∼26-34°C)—can lead to cold stress, which has known negative effects on bone. Therefore, the aim of this study was to test the hypothesis that housing mice at thermoneutrality, thereby ameliorating cold-stress, will prevent social isolation-induced bone loss in male C57BL/6J mice. 16-week-old mice were randomized into social isolation (1 mouse/cage) or grouped housing (4 mice/cage) at either room temperature (∼23°C) or in a warm temperature incubator (∼28°C) for four weeks (N=16/group). As seen in our previous studies, isolated mice at room temperature had significantly reduced bone parameters, including femoral bone volume fraction (BV/TV), bone mineral density (BMD), and cortical thickness (p &lt; 0.001). Contrary to our hypothesis, these effects were not ameliorated by thermoneutral housing. In fact, 28°C housing tended to reduce BV/TV (p = 0.0711) and BMD (p = 0.0883), and significantly reduced cortical thickness (p = 0.0492) within the grouped mice relative to 23°C housing. There were no differences in serum bone resorption or formation markers between the groups, nor were there any differences in fat or lean mass. Social isolation did significantly increase gene expression of the glucocorticoid receptor Nr3c1 (p = 0.0288) and tended to increase expression of Hsd11b1 (p = 0.0947), an enzyme critical for corticosterone activation, across housing temperatures. Increased glucocorticoid activity can enhance brown fat activation, including increased Pdk4 expression. Overall, our data suggest social isolation-induced bone loss is not a result of thermal stress from single housing. These results provide key insights into the potential mechanisms mediating the effects of social isolation on skeletal health and will inform future studies investigating the role of glucocorticoid signaling.
Presentation: 6/1/2024
7999 Tumor Induced Osteomalacia Caused By Glomangiopericytoma
Authors: Kabir Nighat , Campbell Elizabeth , Singh Sarvani 
Published: October 2024

Abstract
Disclosure: N. Kabir: None. E. Campbell: None. S. Singh: None.
Introduction: Tumor induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused primarily by FGF-23 secreting tumors. Excessive production of FGF23 causes hypophosphatemia, decreased phosphate resorption in the gut, increased renal phosphate wasting, and decreased activation of Vitamin D. This leads to decreased bone density, bone pain, proximal muscle weakness, impaired gait, and recurrent fractures. Case Presentation: 44 year old male with a history of recurrent insufficiency fractures and weakness. At the time of evaluation, he reported fracture of tibial growth plate, sacral fracture, and metatarsal stress fracture. Other symptoms included bone pain, fatigue, muscle weakness, and intercostal muscle spasms with exertion. His pain was debilitating, requiring crutches to ambulate. Available labs at that time were significant for hypophosphatemia (1.3 mg/dL), elevated ALP (160 U/L), low 25OH-vitamin D (26 ng/mL), and normal calcium (8.7 mg/dL). Urine studies demonstrated phosphaturia (fractional excretion of phosphate, 62.4%). FGF23 level resulted at the upper limit of normal (210 RU/mL). Pending further evaluation, burosumab was started. Further work up included a 68Ga-PET-DOTATATE scan revealing a somatostatin receptor expressing soft tissue mass in the left sphenoid sinus and posterior left ethmoid sinus. The scan also demonstrated impending bilateral femur fractures, prior rib fractures, and sacral insufficiency fractures. Based on these findings, he was admitted to the hospital and underwent prophylactic, intramedullary nail fixation of his bilateral femur fractures. He underwent resection of skull base tumor with the final pathology revealing a sinonasal glomangiopericytoma. Immunohistochemical stain was positive for CD99 and cyclin D1, and focally positive for SMA, consistent with histopathologic diagnosis. Patient required prolonged inpatient rehabilitation to recover independent ambulation. Discussion: Sinonasal glomangiopericytoma (SNGP) is a mesenchymal tumor that accounts for &lt;0.5% of all nasal and sinus tumors. TIO due to SNGP is extremely rare, with only a few cases reported since the 1990s. As seen with our patient, TIO from SNGP rarely presents with sinonasal symptoms, and can often be overlooked. Our patient hadb significant progression of disease and disability due to numerous delays in diagnosis and management. Definitive cure for TIO can be achieved with complete surgical resection of the tumor, but failure to diagnose in a timely manner can result in decline in quality of life. Our takeaway from this case is that providers should obtain FGF23 levels, especially in the setting of hypophosphatemia and phosphaturia, to complete the work up for osteomalacia.
Presentation: 6/1/2024
12597 Undetectable Intact Pth - Can It Still Be Due To Primary Hyperparathyroidism?
Authors: Bantu S S , Rosenthal R S 
Published: October 2024

Abstract
Disclosure: S.S. Bantu: None. R.S. Rosenthal: None.
Introduction: Primary hyperparathyroidism (PHPT) is the most common cause of hypercalcemia. It is caused by increased levels of parathyroid hormone (PTH) from the parathyroid glands. There is a shift in the clinical presentation of PHPT from symptomatic disease to asymptomatic presentation, due to the inclusion of calcium in basic metabolic panel. We present a patient who had hypercalcemia with undetectable PTH due to PHPT caused by parathyroid adenoma. PTH levels were detectable with resolution of hypercalcemia and improvement in symptoms after the parathyroidectomy. Very few case reports have been reported of PHPT with low or suppressed intact PTH. Case: 66-year-old female with history of hyperlipidemia, hypothyroidism, hypertension, obstructive sleep apnea who was referred for evaluation of hypercalcemia noted on basic metabolic panel. She complained of fatigue, body aches, insomnia and denied any calcium supplements. Calcium 11.1mg/dl, albumin 4.2gm/dl, PTH &lt;1pg/ml, vitamin D 39ng/ml, ionized calcium 1.46 mMol/L, phosphorus 2.6mg/dl, magnesium 2.3mg/dl, PTHrP 0.7pMol/L. After ruling out other causes of hypercalcemia, parathyroid ultrasound showed 1.8 x 1.3 x 1.1cm right inferior parathyroid adenoma. Sestamibi scan showed an approximately 1.5x 1cm lesion in the right inferior parathyroid region confirming the adenoma. A trial of calcitonin was done to make sure it is PHPT to which she responded. Surgery was done with removal of the right inferior parathyroid gland. Intraoperative PTH was done at 5, 10, 15 mins after the removal of the gland which was still undetectable at 1pg/ml. Pathology showed hypercellular parathyroid of 1927mg. Post operatively her symptoms improved with resolution of hypercalcemia and her PTH was detectable at 15.8pg/ml. Discussion: This patient presented as a diagnostic challenge with hypercalcemia, undetectable PTH and parathyroid adenoma. Serial dilutions of the intact PTH were done which didn’t show the hook effect. Undetectable PTH in our case could be explained by the secretion of a mutated form of the intact PTH molecule by the parathyroid adenoma suggesting post-translational change in the molecule that is not measurable by the current assays but still it exerts it effect on the PTH receptor. Our report highlights that PHPT should be considered even in the setting of undetectable serum PTH. More research is needed to study the identification and measurement of the post-translational changes in the intact molecule of the PTH.
Presentation: 6/2/2024
8136 Using High-Resolution Peripheral Quantitative Computed Tomography to Assess Bone Microarchitecture and Guide Osteoporosis Treatment
Authors: Rupani Sawan V , Sfeir Jad , Graeff-Armas Laura 
Published: October 2024

Abstract
Disclosure: S.V. Rupani: None. J. Sfeir: None. L. Graeff-Armas: None.
Bone microarchitecture is an important factor that impacts bone strength. Unlike other factors that affect bone strength, such as bone mineral density and bone turnover, assessment of bone microarchitecture is not yet widely accessible in clinical practice. Computed tomography is the primary method of non-invasively assessing bone microarchitecture. High-resolution peripheral quantitative CT (HR-pQCT) is an emerging imaging modality that provides a three-dimensional assessment of bone densitometry, morphometry, and microarchitecture with a low effective radiation dose. It provides a quantitative and qualitative assessment of cortical and trabecular structural and mechanical properties. We present two similar cases of osteoporosis in males, where knowledge of bone microarchitecture through HR-pQCT helped formulate two distinct and targeted therapeutic approaches. The first case is of a 46-year-old male with a history of idiopathic osteoporosis with multiple nontraumatic vertebral fractures. Given his presentation and age, anabolic therapy such as teriparatide was being considered. He underwent HR-pQCT scanning, which showed average radial trabecular parameters, but his cortical porosity was significantly above average, with similar findings in his tibial parameters. Since teriparatide has been shown to increase cortical porosity, this would not be the best option for our patient, given the risk of further weakening of the microarchitecture of his cortical bone. Therefore, denosumab, which has been shown to decrease cortical porosity, was chosen. Our second patient is a 52-year-old male with idiopathic osteoporosis with multiple nontraumatic vertebral fractures, whose HR-pQCT showed average cortical parameters at both the radius and tibia but low trabecular number and increased trabecular separation at both sites. Since teriparatide increases trabecular thickness and mass, we could confidently choose teriparatide for this patient, with less concern for significant deleterious effects on his cortical bone parameters. These case reports highlight the impact that the assessment of qualitative properties of bone, such as microarchitecture, can have in the management of osteoporosis. Currently, the lack of sufficient validated normative data for HR-pQCT limits its widespread use in the diagnosis of osteoporosis and fracture prediction. However, given that HR-pQCT can characterize the properties of trabecular and cortical bone, it may have a role in helping guide osteoporosis treatment, especially in challenging and atypical cases.
Presentation: 6/3/2024
6724 A Broken Heart Due to Excess Thyroid
Authors: Subramani Rashmi , Subramani Raaghul , Zeykan Violeta 
Published: October 2024

Abstract
Disclosure: R. Subramani: None. R. Subramani: None. V. Zeykan: None.
Introduction: Tachycardia-induced cardiomyopathy related to thyrotoxicosis is an uncommon yet serious complication affecting fewer than 1% of individuals with hyperthyroidism. Restoring a euthyroid state can potentially reverse the abnormal cardiac structure and function. Here we report a case of tachycardia-induced cardiomyopathy secondary to thyrotoxicosis Case Summary: A 52-year-old woman with a history of hypertension presented with recent-onset exertional dyspnea, a nonproductive cough, and paroxysmal nocturnal dyspnea. On examination, she exhibited tachycardia (heart rate: 150/min), tachypnea, hypertension, and was afebrile. Physical findings included a mildly enlarged, firm, non-tender thyroid gland bilaterally, without exophthalmos or tremors. Auscultation revealed bilateral crackles in the left lower lung fields. Laboratory analysis revealed undetectable TSH (&lt;0.02 uIU/mL), elevated free T4 (5.3 ng/dL), free T3 (16.30 pg/mL), thyroid stimulating immunoglobulin (TSI) at 216%, and NT proBNP at 8528 pg/mL. Neck ultrasound and CT confirmed diffuse enlargement of the thyroid gland. Transthoracic echocardiography (TTE) displayed severely depressed left ventricular systolic function, estimating an ejection fraction (EF) of 25-30%. Initial management involved intravenous beta-blockers for heart rate control, IV Lasix, and IV hydrocortisone. Subsequently, the patient received propylthiouracil, propranolol, and prednisone, resulting in symptomatic improvement. A follow-up TTE after 6 months revealed an improved EF of 50%. Discussion: The pathophysiologic mechanisms underlying thyrotoxic cardiomyopathy encompass several factors, including tachycardia-induced cardiomyopathy, direct myopathic effects induced by the T3 hormone, and concurrent autoimmune myocarditis associated with Graves' disease. Thyroid hormone exerts a comprehensive impact on nearly all tissue and organ systems, heightening basal metabolic rate and subsequently increasing preload, myocardial contractility, and cardiac output. While thyrotoxicosis-related congestive heart failure (CHF) is relatively uncommon among patients hospitalized for acute CHF, addressing hyperthyroidism and CHF through definitive treatment yields a more favorable prognosis compared to cases of acute CHF stemming from other etiologies. The intricate interplay of these mechanisms highlights the importance of a comprehensive approach in managing thyrotoxic cardiomyopathy, emphasizing the need for targeted interventions to address both the underlying thyroid dysfunction and associated cardiac manifestations.
Presentation: 6/3/2024
6664 A Case of Undistinguished Congenital Adrenal Hyperplasiain a Patient with Hypertensive Emergency and Hypokalemia
Authors: Signore V L Del , Kaufman S T 
Published: October 2024

Abstract
Disclosure: V.L. Del Signore: None. S.T. Kaufman: None.
CAH is a group of autosomal recessive disorders resulting in alterations of adrenal steroid biosynthesis. With 95% of CAH cases due to 21-hydroxylase deficiency; other causes are rare. The metabolic, phenotypic, and physiologic derangements are specific to the altered enzymatic pathways, most of which are life threatening. Identifying the enzymatic defect is crucial to treat the patient. We present a case of undifferentiated CAH in an adult resulting in significant systemic illness. A 26-year-old well virilized male presented with chief complaint of shortness of breath, lower extremity swelling, and abdominal distension for 3 weeks. He was found to have acute decompensated heart failure with LVEF 20-25%, NSTEMI, atrial fibrillation, hypertensive emergency with BP of 224/102, and potassium (K+) of 2.7 (3.5-5mmol/L). PMH included hypertension and CAH diagnosed at birth. Patient was unsure of his CAH defect. Pediatric endocrinology prescribed glucocorticoids until age 17 at which point he was told steroids were no longer required. He had been lost to follow up for 9 years. Pediatric records were unattainable. Patient remained hypokalemic and hypertensive despite aggressive K+ repletion and multiple IV antihypertensives. Endocrine work up revealed renin 0.19 (0.25- 5.82ng/mL/hr), aldosterone 4 (&lt; or = 21ng/dL), DHEAs 97 (74-617ug/dL), FSH &lt;0.3 (1.4 - 18.1 m[IU]/mL), LH &lt;0.3 (1.5 - 9.3 m[IU]/mL), total testosterone 306 (250-1,100 ng/dL), SHBG 32 (10-50nmol/L), progesterone 7 (0.2-1.4 ng/mL), ACTH 345 (6-50 pg/mL), AM cortisol 4.4 (5-23 ug/dL), 17 hydroxyprogesterone 311 (32-307 ng/dL), androstenedione 1,926 (50-220 ng/dL), 11-deoxycortisol &gt;10,000 (&lt; or = 119 ng/dL). Cosyntropin stimulation test: 30-minute cortisol 11.1 (&gt;18 ug/dL) and 60-minute cortisol 10.4 (&gt;18 ug/dL). Based on clinical and lab findings a diagnosis of 11-beta hydroxylase deficiency was made. Spironolactone was started to counteract the excessive mineralocorticoid effects of deoxycorticosterone and hydrocortisone to decrease ACTH production. With this treatment, patient’s potassium and blood pressure gradually improved. IV antihypertensives were weaned as he transitioned to oral agents. This case demonstrates the importance of understanding and identifying the underlying pathophysiology of CAH to treat patients appropriately. This patient had a mineralocorticoid excess state, but adequate cortisol precursors to prevent adrenal crisis. He requires glucocorticoid therapy to prevent excessive ACTH from driving their BP and metabolic derangements. With appropriate diagnosis of 11-beta hydroxylase deficiency, patient’s excess risk of morbidity and mortality due to the downstream effects of uncontrolled CAH can be minimized.
Presentation: 6/3/2024
8226 A Diagnostic Challenge: Factitious Hypobicarbonatemia in Severe Hypertriglyceridemia
Authors: Rafat Ummara , Azmat Shazia , Siddiqui Mahrukh , Alshantti Raeda , Kircheva Diana , Trendafilova Victoria 
Published: October 2024

Abstract
Disclosure: U. Rafat: None. S. Azmat: None. M. Siddiqui: None. R. Alshantti: None. D. Kircheva: None. V. Trendafilova: None.
Background: Serum CO2 levels measured by a chemistry analyzer usually correlate with calculated bicarbonate levels on an ABG. There are some instances however, when this is not the case. Severe hypertriglyceridemia can cause serum bicarbonate levels to appear falsely low on metabolic panel. Clinical Case: A 48-year-old man was referred to Endocrinology Clinic for evaluation of hypogonadism and severe hypertriglyceridemia. Routine labs revealed a plasma CO2 of 11 mmol/L (20-31). Na was 133 mmol/L (136-145), K was 4.4 mmol/L (3.5-4.7), Chloride was 101 mmol/L (98-109) and anion gap was 25 (8-20) measured using a Siemens Vista enzymatic chemistry analyzer. His triglycerides were &gt; 1100 mg/dL (0-150), above upper detection limits of the analyzer. The patient reported fatigue and mild abdominal pain. He was admitted to the hospital for further evaluation. His lipase was 41 U/L (12-73), lactic acid 1.2 mmol/L (0.50-2.20). ABG showed pH of 7.41, HCO3 of 26.6 mmol/L (22-29), and anion gap of 7 (10-20). The patient was well-appearing with normal vital signs and normal physical exam. He was made NPO and started on pravastatin, fenofibrate and fish oil. Once his triglycerides were &lt; 1000 mg/dL, he was started on a very low-fat, low-carbohydrate diet. The CO2 level on BMP normalized on day 3 of hospitalization, when triglycerides measured 1010 mg/dL. No other treatment was given for the low CO2 levels. It does not appear that other lab indices were significantly affected by the hypertriglyceridemia. Review of Literature: A BMP measures serum total carbon dioxide using a chemistry analyzer using either an enzymatic/spectro-photometric method, or an electrode-based method; an ABG sample calculates plasma bicarbonate with the Henderson-Hasselbach equation, using the pH and partial pressure of pCO2 in the sample. Enzymatic analyzers measure CO2 using spectrophotometry and decrease in light absorbance is proportional to the sample’s CO2 levels. It is postulated that severely high triglycerides can interfere with this reaction and cause spuriously low CO2 levels, a phenomenon called pseudohypobicarbonatemia. One proposed mechanism for interference with the enzymatic assay method is turbidity causing a falsely low measured CO2 level. Verghese et al found that the severity of the CO2 measurement error positively correlates with the severity of triglyceride elevation. Conclusion: Awareness of the phenomenon of hypertriglyceridemia-induced pseudohypobicarbonatemia can prevent misdiagnosis or delays in diagnosis, as well as unwarranted testing and treatment.
Presentation: 6/3/2024
6966 A Rhythmic Life-Threatening Enigma Unveiled: KCNH2 Mutation-Associated Torsades de Points Unmasking Primary Hyperaldosteronism in Cardiological Realm
Authors: Dejprapasorn Saran , Nopparatana Napawadee , Soonthornpun Supamai , Leelawattana Rattana , Kietsiriroje Noppadol , Limumpornpetch Sunti , Nilmoje Thanapon , Lohawijarn Watchara , Wongsuttipakorn Tanate , Choochuen Pongsakorn , Limumpornpetch Padiporn 
Published: October 2024

Abstract
Disclosure: S. Dejprapasorn: None. N. Nopparatana: None. S. Soonthornpun: None. R. Leelawattana: None. N. Kietsiriroje: None. S. Limumpornpetch: None. T. Nilmoje: None. W. Lohawijarn: None. T. Wongsuttipakorn: None. P. Choochuen: None. P. Limumpornpetch: None.
Introduction: Primary hyperaldosteronism (PA) is characterized by hypertension and hypokalemia. However, its ability to masquerade life-threatening Torsades de Pointes makes it an unusual and dismissed diagnosis, revealing the link between PA and serious arrythmia. Clinical Case A 30-year-old female experienced three episodes of palpitations, followed by syncope. Upon admission, her blood pressure was 147/87 mmHg. ECG showed prolonged QT intervals with potassium level was 2.6 mmol/L (3.5-5.0 mmol/L). Continuous cardiac monitoring captured Torsades de Pointes. Despite potassium replacement, long QT still persisted. Pathogenic variant, c.2592+1G&gt;A, within KCNH2 was discovered. Aldosterone concentration showed 69.65 ng/dL (9.70-62.60 ng/dL) and plasma renin activity was 0.12 ng/mL/h (1.50-5.70 ng/mL/h). Aldosterone-to-renin ratio was 580. Aldosterone post 4-h saline infusion test was 31.71 ng/dL which were consistent with PA. Adrenal unenhanced CT scan identified bilateral adrenal nodules (right 1.3 cm, left 1.1 cm). After receiving a cardioverter-defibrillator and spironolactone, the patient has had no palpitations, and their potassium level has remained normal. Clinical lessons: PA rarely presents ventricular arrhythmia. KCNH2 mutation may link between long QT syndrome (LQTS) and PA arises. LQTS type 2 is attributable to KCNH2 mutations, impacting potassium channel subunits crucial for adjusting currents during sympathetic activation. This is essential for shortening the QT interval with increasing heart rate. KCNH2 mutations disrupt this process, prolonging the QT interval and heightening the risk of arrhythmias. Aldosterone synthesis relies on calcium signaling triggered by potassium currents. Adrenal cortex hosts approximately 90 potassium channels genes, including KCNJ5 and KCNH2. Mutations in gene can disrupt the calcium signaling cascade, leading to excessive aldosterone production. While KCNJ5 mutation is well-documented in PA, the potential correlation between KCNH2 mutations and a similar mechanism remains unexplored in clinical reports to date. This case highlights the importance of a thorough comprehension of genetic cause contributing to pathogenesis of PA with complex clinical presentations.
Presentation: 6/1/2024