bluuebunny/crossref_metadata_2025_split huggingface dataset:
LBSAT145 Localizing The "Difficult" Parathyroid Tumor
Authors: Graf Akua , Cochran Craig , Abijo Tomilowo , Sadowski Samira Mercedes , Nilubol Naris , Simonds William F , Weinstein Lee Scott , Chang Richard , Jha Smita 
Published: November 2022

Abstract

Background
The identification of parathyroid tumor(s) in patients with persistent/recurrent primary hyperparathyroidism (PHPT) is critical for a successful re-operative surgery. We describe our experience with invasive studies for parathyroid tumor localization and provide follow-up data regarding our experience with selective arterial hypocalcemic stimulation with central venous sampling (SAHSCVS).

Methods
We identified patients who underwent pre-operative invasive testing for localization of parathyroid tumor at our center. At our center, only PHPT patients with history of prior neck surgery without definitive findings on non-invasive testing (sestamibi, ultrasound, CT, MRI) proceed to invasive studies. The result of each invasive localization study (arteriogram, SAHSCVS and selective venous sampling (SVS)) was categorized as true-positive (TP), false-positive (FP) and false-negative (FN) based on biochemical outcome.

Results
Ninety-five patients with 98 tumors underwent invasive testing for parathyroid tumor localization. All but one had recurrent disease. Sixty-two patients (65%) had "apparently sporadic" PHPT, 19/95 (20%) had MEN1, three had parathyroid cancer (PC) and the remaining had other heritable forms of PHPT. Median age of index PHPT presentation was 47 [34-58] years. Of 87 tumors with available operative details, 66 (76%) were in the neck, 20 in the mediastinum (23%), and one in the forearm at site of prior autograft. Seventy-two (83%) showed hyperplasia or hypercellularity on histology. Median tumor size was 5 mm. Arteriogram, SAHSCVS and SVS accurately localized the tumor in 47/90 (52%), 54/90 (60%) and 49/61 (80%) tumors respectively. Positive Predictive Value of arteriogram, SAHSCVS and SVS was 47/50 (94%), 55/64 (86%) and 49/59 (83%) respectively. Both sensitivity and PPV showed no significant difference between patients with MEN1+PC vs. others. Among the 54 tumors accurately localized by SAHSCVS, SVS was performed in 29/54 with complete concordance. Twenty-seven tumors (30%) were missed (FN) on SAHSCVS, of these 14/25 (56%) were also missed on arteriogram. Nevertheless, 16/20 (80%) localized accurately on subsequent SVS. SAHSCVS was FP in localizing nine tumors - seven (78%) of these did not show a blush on arteriogram. All pre-operative localizing studies were unrevealing in 9/98 presentations (10%).

Conclusion
Patients with difficult to localize parathyroid tumors have clinical features suspicious for germline-predisposition forms of PHPT indicated by recurrent disease, hyperplastic glands, and age of index presentation. SAHSCVS can be a useful adjunct in patients who require invasive localization. 90% of these tumors are localized with combination of current non-invasive and invasive testing. AcknowledgementThis research is supported by the Intramural Research Program of NIDDK, NCI and NIH Clinical Center.
Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.
LBSAT229 Extended-release Calcifediol Effectively Raised 25-hydroxyvitamin D In CKD Despite Obesity
Authors: Strugnell Stephen A , Ashfaq Akhtar , Bishop Charles W 
Published: November 2022

Abstract
Inadequate levels of serum total 25-hydroxyvitamin D (25D) in chronic kidney disease (CKD) are associated with an increased risk of secondary hyperparathyroidism (SHPT). Serum 25D can be difficult to raise sufficiently with vitamin D supplements (cholecalciferol or ergocalciferol) to effectively lower elevated parathyroid hormone (PTH) levels especially in overweight patients. Obesity is common in CKD and requires attention when vitamin D repletion is considered. Vitamin D supplements are fat-soluble molecules which accumulate in adipose tissue. They have low affinity for serum vitamin D binding protein and are poorly mobilized from adipose tissue into circulation for hepatic activation. Recent studies suggest that serum 25D levels of ≥50 ng/mL are necessary to produce significant PTH reductions in nondialysis patients. Data were analyzed from two identical randomized clinical trials investigating the efficacy and safety of treating adult nondialysis patients with extended-release calcifediol (ERC; n=285) or placebo (n=144) to see if ERC raised 25D to at least 50 ng/mL in all body weight categories, with subgroup analyses by race, gender and age. On enrollment, subjects had eGFR of ≥15 and &lt;60 mL/min/1.73 m2, PTH ≥85 and &lt;500 pg/mL, serum 25D ≥10 and &lt;30 ng/mL, corrected serum calcium ≥8.4 and &lt;9.8, serum phosphorus ≥2. 0 and &lt;5. 0, absence of nephrotic range proteinuria (&gt;3 mg/mg creatinine) and no history of parathyroidectomy or renal transplantation. These subjects had mean (SD) age of 65.4 (10.9) years, serum 25D at baseline of 19.6 (5.4) ng/mL, body weight of 97.8 (24.3) kg and BMI of 34.7 (7.9) kg/m2. Fifty percent were male, 64. 0% White, 32.9% African-American or Black, and 3.1% Other, and 20% were Hispanic. A total of 356 subjects completed a 20- to 26-week treatment period per-protocol and were included in the analysis. Enrolled subjects ingested a 30 mcg capsule of ERC (OPKO Pharmaceuticals, Miami) daily for 12 weeks followed by one or two capsules (30 or 60 mcg) daily for a 14 more weeks. Control subjects received matching placebo. Mean (SD) serum 25D remained unchanged with placebo treatment but rose progressively with ERC treatment to 67.1 (21.6) ng/mL (mean of weeks 20-26). The observed increases in serum 25D were inversely related to body weight but exceeded 50 ng/mL in all body weight categories, irrespective of race (White vs. African-American or black), gender or age (&lt;70 vs. ≥70 years). Side effects observed at these levels were similar to placebo. These data showed that ERC successfully raised mean serum 25D to at least 50 ng/mL irrespective of body weight, race, gender or age.
Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.
ODP125 Soft Bones in Crohn's: Tumor-induced osteomalacia and inflammatory bowel disease
Authors: Habbsa Samima , Farhan Hisham , Thomas Afton , George Lauren , Hu Yinin , Whitlatch Hilary 
Published: November 2022

Abstract

Introduction
Bone loss is common in patients with inflammatory bowel disease (IBD) and is usually attributed to Vitamin D malabsorption, treatment with glucocorticoids or chronic inflammation. We report a case of bone loss, hypophosphatemia, and atypical fractures in a patient with IBD who was ultimately diagnosed with tumor-induced osteomalacia (TIO), a rare paraneoplastic syndrome of chronic hypophosphatemia and impaired vitamin D metabolism.

Clinical Case
A 39-year-old male presented for evaluation of low bone density, hypophosphatemia, and multiple stress fractures. His medical history includes Crohn's disease in biochemical remission on adalimumab and bilateral hip avascular necrosis. There was no history of significant steroid use or known family history of metabolic bone disease. He was previously highly active as a modern dancer. Over the course of 3 years, he developed progressive diffuse bony pain and he became wheelchair-bound. A whole body bone scan visualized multiple age-indeterminate atraumatic fractures, including bilateral metatarsal fractures and numerous rib fractures. Dual energy x-ray absorptiometry showed significantly low bone mass for age (Z-scores –3.4, -3.1, -3.7 at the L1-L4 spine, total right femur and right femoral neck, respectively). Physical exam was notable for a soft, subcutaneous 8 cm mass posterior to the left paraspinal muscle at the level of T12, which had previously been diagnosed as a lipoma. Laboratory evaluation revealed phosphorus 1 mg/dL (2.5-4.5 mg/dL), calcium 9.1 mg/dL (8.6-10.2 mg/dL), PTH 35 pg/mL (15-65 pg/mL), c-telopeptide 592 pg/mL (38-724 pg/mL), bone specific alkaline phosphatase 114.5 mcg/L (4-27 mcg/L), vitamin D-1,25 8.9 pg/mL (19.9-79.3 pg/mL), and vitamin D-25 34 ng/mL (normal &gt;30 ng/mL). Fibroblast growth factor-23 (FGF-23) level was 1200 RU/mL (44-215 RU/mL), consistent with TIO. Thyroid function, dexamethasone suppression test, testosterone and IGF-1 were normal. Ga-DOTATATE PET scan demonstrated that the paraspinal soft tissue mass was strongly somatostatin avid. The patient was treated with oral calcitriol and phosphate replacement. He underwent a biopsy of the left paraspinal mass, which was consistent with a bland epithelioid and spindle cell neoplasm, most suggestive of a phosphaturic mesenchymal tumor. He is scheduled for a radical resection of the soft tissue mass.

Conclusion
To date, there are no published case reports of TIO with coexisting IBD. Inflammatory cytokines, such as tumor necrosis factor alpha, have been shown to positively correlate with FGF-23 levels, and FGF-23 has been documented to be elevated during IBD flares. Given this, the presence of IBD may portend a worsened metabolic bone prognosis in patients who simultaneously develop FGF-23 secreting tumors.
Presentation: No date and time listed
ODP129 Variation in 25(OH)D Levels, Measurement Methods and Prevalence of Vitamin D Deficiency: a Systematic Review and Meta-analysis
Authors: Premaor Melissa , Fernandes Maira , Campos Fernanda , Brondani Juliana , Comim Fabio 
Published: November 2022

Abstract
Vitamin D deficiency is a common disease with high morbidity. Although, there are several studies evaluating its prevalence in different Brazilian regions, its actual prevalence it not known. Furthermore, some research suggests that serum levels of 25-hydroxyvitamin D [25(OH)D] may vary according to the measurement technique. This variation may affect the results of the prevalence of vitamin D deficiency in Brazil, given that its diagnosis is made by measuring 25(OH)D, regardless of the technique used. Our study aimed to investigate whether 25(OH)D values vary according to the 25(OH)D measurement technique in Brazil. Therefore, a systematic review including controlled clinical trials, cohort studies, cross-sectional studies, and case-control studies was performed. Studies that included all participants with some underlying pathology were excluded. The bibliographic search was carried out in PubMed, BIREME, and EMBASE databases. Two protocol members independently performed the selection and extraction of data from the studies. A third member reviewed this selection and extraction. In total, 1,166 studies were found, of which 122 had their full texts evaluated, 34 studies evaluated the serum levels of 25(OH)D, and described the technique used to measure this hormone. A total of 356,565 participants with a mean age between 18 and 80 years were included in the analysis. The prevalence of vitamin D deficiency [25(OH)D &lt; 20 ng/mL] and vitamin D insufficiency [25(OH)D &lt; 30 ng/mL] in Brazil were, respectively, 29.7% (95%CI 25 .6 to 34.1%) and 65.2% (95%CI 62.5 to 87. 0%). Mean serum levels of 25(OH)D varied according to the technique and brand used to measure this hormone. The mean 25(OH)D values according to the technique used: chemiluminescence 25.5 ng/mL (95%CI 24. 0 to 27. 0 ng/mL); ELISA 41 (95%CI 37. 0 to 46.1 ng/ml); HPLC 28.7 ng/ml (95%CI 23.9 to 33.6 ng/ml) and radioimmunoassay 24.5 ng/ml (95%CI 20.2 to 28.8 ng/ml); p&lt;0. 0001. This variation is associated with the heterogeneity of the pooled results of vitamin D prevalence in Brazil. In conclusion, these findings suggest that the prevalence of vitamin D in Brazil may vary according to the measurement technique used. Better standardization of the results of the 25(OH)D measurement assays becomes urgent that we can have a more precise estimate of this problem.
Presentation: No date and time listed
OR13-2 Characterizing the Impact of Burosumab on Bone Health in Children with X-Linked Hypophosphatemia: Results from Year 1 of the Disease Monitoring Program
Authors: Carpenter Thomas , Cassinelli Hamilton , Glorieux Francis , Hetzer Joel , Merritt II J Lawrence , Moreira Carolina A , Portale Anthony , Ward Leanne , Woo Claudine , Imel Erik 
Published: November 2022

Abstract
X-linked hypophosphatemia (XLH) is a rare, heritable disorder wherein excess FGF23 leads to renal phosphate wasting and impaired activation of vitamin D. XLH is characterized by rickets and osteomalacia leading to bone pain, skeletal deformities, and short stature. The XLH Disease Monitoring Program (DMP; NCT03651505) is a prospective, multinational outcomes study of the longitudinal progression of clinical, radiographic, and biochemical features of XLH in children and adults. We assessed the impact of the recombinant human IgG1 monoclonal antibody to FGF23, burosumab, on measures of bone health in children with XLH at Year 1 of the DMP.
As of March 2021, 287 children (&lt;18 years) had completed the Year 1 visit. Participants were grouped by when they first received burosumab: Group 1, prior to DMP enrollment (N=68; mean (SD) age 9.5 (3.6) years); Group 2, during the DMP (N=150; 8.7 (5.0) years); Group 3, never, but receiving conventional therapy (N=69; 8.8 (5.3) years).
Before receiving burosumab, serum phosphorus levels were below normal; after burosumab initiation, serum phosphorus in Groups 1 and 2 rapidly normalized, with sustained improvements up to 3 years of treatment. Serum phosphorus remained low in Group 3. Before burosumab, serum alkaline phosphatase levels were above normal; with continued burosumab therapy, mean levels gradually declined towards normal and were maintained for up to 4 years.
The Radiographic Global Impression of Change (RGI-C) assessed rickets and lower limb deformity from DMP baseline to Year 1, with positive values denoting improvement. Mean (SD) RGI-C rickets global scores were +1.0 (0.9) for Group 1 (n=44), +1.5 (0.7) for Group 2 (n=39), and +0.3 (1.2) for Group 3 (n=3). Lower limb deformity RGI-C scores were +0.3 (0.6) for Group 1 (n=42), +0.4 (0.8) for Group 2 (n=39), and +0.8 (1.1) for Group 3 (n=3). Height Z-score change from DMP baseline at Year 1 was 0.1 (0.3) for Group 1 (n=58), 0.1 (0.4) for Group 2 (n=90), and -0.8 (3.1) for Group 3 (n=18). There were no new safety concerns or reports of hyperphosphatemia.
These real-world data affirm that normalization of serum phosphorus is rapid and sustained following burosumab initiation, resulting in improved serum alkaline phosphatase levels which positively impact bone mineralization. Improvements in rickets, growth, and lower limb deformity occur in the first year of burosumab treatment and continue in those who started burosumab prior to entering the DMP. The absence of new safety concerns or reports of hyperphosphatemia up to 4 years after burosumab initiation is also notable. The 10-year DMP study design will provide understanding of long-term effects in these patients with continued burosumab therapy.
Presentation: Sunday, June 12, 2022 11:15 a.m. - 11:30 a.m.
OR13-4 Bone Mineral Density in Transgender Youth on Gender Affirming Therapies
Authors: Ma Nina , Moreau Kerrie , Nadeau Kristen , Rothman Micol , Nokoff Natalie 
Published: November 2022

Abstract

Background
2% of youth identify as transgender. Many have puberty blocked with gonadotropin-releasing hormone analogues (GnRHa), followed by testosterone (T) or estradiol (E2). Bone mineral density (BMD) effects of these therapies are understudied.

Objective
For youth on GnRHa alone or T or E2 +/- GnRHa, to evaluate: (1) BMD z-scores; (2) BMD z-score differences for those +/-GnRHa; and (3) associations between GnRHa duration and BMD z-score.

Methods
Cross-sectional study of transgender youth (n=56 age 10.4-19.8 years, 53% female sex assigned at birth) undergoing total body dual-energy X-ray absorptiometry (Hologic Discovery A). Data are presented as median and interquartile range, group differences evaluated with Mann Whitney U tests and associations with Spearman correlations.

Results
BMD z-scores on GnRHa alone (n=19) were -0.5 (-1.4, 0.3) using male norms and -0.8 (-1.7, 0.3) using female norms. BMD z-score for transgender males (TM) on T (n=21, 5 with past GnRHa): -0.2 (-0.6, 0.0) using male norms, 0.4 (-0.3, 0.8) using female norms. BMD z-score for transgender females (TF) on E2 (n=16, 6 on current/past GnRHa): -0.4 (-1.2, 0.3) using male norms, -0.2 (-1.0, 0.7) using female norms. TM on T with prior GnRHa had significantly lower BMD z-scores than TM on T alone (p=0.004); but no differences for TF on E2 +/- GnRHa. GnRHa duration was inversely correlated with BMD z-score (male norms: r=-0.5, p=0.005, female norms: r=-0.4, p=0.029). BMD z-score was unrelated to length of T/E2 therapy or sex steroid concentrations.

Conclusions
Longer durations of GnRHa therapy were associated with worse BMD z-scores.
Presentation: Sunday, June 12, 2022 11:45 a.m. - 12:00 p.m.
RF32 | PSUN49 To Repeat or Not to Repeat: The Question of Aldosterone and Renin Variability
Authors: Ng Elisabeth , Gwini StellaMay , Libianto Renata , Choy Kay Weng , Fuller Peter , Shen Jimmy , Yang Jun 
Published: November 2022

Abstract
Plasma aldosterone concentration (PAC), renin levels and aldosterone-renin ratio (ARR) are used to screen for primary aldosteronism (PA). A recent study (Yozamp et al. Hypertension 2021) reported substantial intraindividual variability of PAC and ARR (using plasma renin activity) in the context of usual antihypertensive therapy. The intraindividual variability of PAC and direct renin concentration (DRC), a more widely used measurement of renin, in the absence of interfering medications is unknown but important where a single ARR is used to screen for PA.
The aim of this study was to evaluate the intraindividual variability of PAC, DRC and ARR in a cohort of patients with and without PA. Patients who attended an Endocrine Hypertension Service from May 2017 to July 2021 with at least two ARR measurements off interfering medications were retrospectively evaluated. While the measurements were performed at several hospital and community laboratories, the same analyser was used. PA was confirmed using the seated saline suppression test following an abnormal ARR &gt;70 pmol/L: mU/L. PAC and DRC variability was calculated as coefficient of variation (CV=standard deviation/mean×100) and percent difference (PD=difference between highest and lowest values/mean×100).
A total of 223 patients were analysed (55% female, median age 52 years), including 162 with PA (25% with unilateral disease). Significant variability in both PAC and DRC was observed in the PA group (CV: 24%, 41%; PD: 46%, 76% respectively) and non-PA group (CV: 22%, 40%; PD: 38%, 65% respectively), which was higher than the assays’ analytical variability. The ARR was also highly variable within individuals, in both the PA group (CV: 42%; PD: 74%) and non-PA group (CV: 37%; PD: 61%). Variability was not significantly different between PA subtypes, and persisted irrespective of age, gender and degree of hypertension. Sixty-two patients (39%) with PA could have had a missed diagnosis if the ARR had not been repeated, i.e., had at least one ARR &lt;70 pmol/L: mU/L, while 28 (46%) without PA had at least one abnormal ARR &gt; 70.
Intraindividual variability in PAC, DRC and ARR occurs in a significant number of patients being investigated for PA. These results support the need for at least two ARR on separate occasions before PA is excluded or further investigated.
Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m., Monday, June 13, 2022 1:06 p.m. - 1:11 p.m.
LBODP036 A Case of Euglycemic Diabetic Ketoacidosis After Distal Pancreatectomy
Authors: Turner James , Steinberg Helmut O 
Published: November 2022

Abstract
The patient is a 68-year-old female with a past medical history of type 2 diabetes mellitus, pancreatic mass, hypertension, hyperlipidemia, and coronary artery disease who presented to the hospital for elective surgical resection of her pancreatic mass. She underwent robotic-assisted laparoscopic distal pancreatectomy, splenectomy, and gastric wedge resection. Her hospital course was complicated by post-operative bleeding with hemoperitoneum the day after her initial surgery. She returned to the operative room for exploratory laparotomy during which the source of bleeding was identified and repaired. She was transferred to the intensive-care unit for post-operative monitoring. On the fourth day of admission, the patient became markedly acidotic. Her labs revealed a bicarbonate level of 12 mmol/L and a pH of 7.24. Her anion gap was elevated to 17. Endocrinology was consulted for suspected euglycemic diabetic ketoacidosis. Beta-hydroxybutyrate was elevated to 5.10 mmol/L (0 - 0.29 mmol/L). The patient's blood glucose was 159 mg/dL. Of note, the patient does take Empagliflozin at home. This medication has been associated with euglycemic diabetic ketoacidosis; however, she had not received this medication for five days prior to the onset of diabetic ketoacidosis. Glucosuria is expected to return to baseline after discontinuation of Empagliflozin within approximately three days. A urinalysis was checked at the time of consultation, and the patient did have a large amount of glucose in her urine which suggests that Empagliflozin was still acting to produce glucosuria. The patient was treated with intravenous insulin and fluids per the institution's protocol for the management of diabetic ketoacidosis. Her acidosis rapidly improved, and she was transitioned to subcutaneous insulin to manage her diabetes prior to discharge. This is an interesting case of euglycemic diabetic ketoacidosis due to the multifactorial precipitants: the dwindling effect of Empagliflozin five days after discontinuation, the loss pancreatic beta cell mass after distal pancreatectomy, and the stress of multiple surgeries complicated by life-threatening post-operative bleeding.
Presentation: No date and time listed