bluuebunny/crossref_metadata_2025_split huggingface dataset:
7337 High Parathyroid Hormone (PTH) Due To Immunoassay Interference
Authors: Alkeshbhai Mendpara Vaidehi , McShane Adam J , Zeinab Khan Leila 
Published: October 2024

Abstract
Disclosure: V.A. Mendpara: None. A.J. McShane: None. L.Z. Khan: None.
Background: PTH levels are not always accurate. This case illustrates immunoassay interference in a female with markedly abnormal PTH values. Understanding immunoassay interference in diverse hormonal assessments can prevent diagnostic inaccuracies. Clinical Case: A 63-year-old female with osteopenia underwent serum parathyroid hormone (PTH) testing as part of a thorough bone evaluation. The initial PTH level revealed an abnormal level of 4008 pg/mL (normal range: 15 to 65 pg/mL). The follow-up PTH level with the same assay continued to result in elevated values of &gt;5000 pg/mL. The medication list was negative for biotin use, which is a well-known interfering substance in the PTH assay. Clinical evaluation was negative for hyperparathyroidism symptoms, and thyroid/parathyroid ultrasound was normal, as were serum levels of phosphate, vitamin D, and calcium. No PTH values had been checked for patients in the past after an extensive review of prior records. The initial PTH testing used the Roche Elecsys PTH STAT assay. To investigate a potential immunoassay interference, the following studies were performed: First, the sample was diluted with polyethylene glycol (PEG) to precipitate large molecular weight proteins; second, the sample was treated with a commercial heterophilic blocking reagent (Scantibodies Laboratory); and lastly, the sample was assayed utilizing a different PTH vendor (Siemens Atellica, chemiluminescent immunoassay). The PEG and heterophilic blocking treatments resulted in significantly lower PTH concentrations of 895.6 and 40.7 pg/mL, respectively. We do not anticipate a change in PTH levels in samples supplemented with blocking reagents or PEG without interference. The result from Siemens’ assay was markedly lower at 43.4 pg/mL. Both the Siemens and Roche assays employ mouse antibodies; however, the antibodies are proprietary between the vendors. This results in potentially different anti-mouse antibody epitope targets. Due to a history of advanced ovarian cancer, the patient was taking Oregovomab, a murine monoclonal antibody, as therapy for her advanced disease. It is unclear if this medication resulted in assay interference, but it is possible. Discussion: In summary, the discrepancy in PTH assay results highlights the need to consider immunoassay interference, particularly in patients with a history of cancer on immunotherapy agents. Our case highlights the importance of the clinician’s review of medications when assessing patients. While prior PTH assays were not conducted before the patient started Oregovomab, the potential development of interfering antibodies warrants consideration. Clinicians should be vigilant for atypical results and collaborate closely with laboratory professionals, as detecting interfering substances can result in misdiagnosis.
Presentation: 6/2/2024
6871 Hungry Bone Syndrome After Parathyroidectomy in End-Stage Kidney Disease: A Case Report Analysis
Authors: Rani Richa , Mullarkey-Desapio Cathleen 
Published: October 2024

Abstract
Disclosure: R. Rani: None. C. Mullarkey-desapio: None.
Introduction: Hungry Bone Syndrome (HBS) is a rare yet severe complication following parathyroidectomy, characterized by pronounced hypocalcemia subsequent to a rapid decline in parathyroid hormone (PTH) levels. Renal hyperparathyroidism (RHPT) carries a heightened risk of HBS compared to primary hyperparathyroidism (PHPT), with prevalence varying from 15% to 25% in PHPT to as high as 75-92% in RHPT. This elevated risk in RHPT is attributed to chronically elevated PTH levels, both in terms of duration and intensity as compared to PHPT. Preoperative predictors for HBS occurrence and severity include younger age, larger gland size, lower preoperative calcium levels, elevated bone turnover markers, and the magnitude of PTH elevation. Case Report: We present a case of a 36-year-old female with End-Stage Renal Disease (ESRD) requiring dialysis, complicated by renal osteodystrophy and a radial fracture, unresponsive to medical therapy, who was admitted for parathyroidectomy. Preoperative labs revealed calcium at 8.3 mg/dL, phosphate at 4.1 mg/dL, alkaline phosphatase (ALP) at 797 IU/L, and an extremely elevated parathyroid hormone (PTH) level at 4139 pg/ml. Within 24 hours of parathyroidectomy (three and a half glands were removed, the largest weighing 0.7gm), her PTH levels declined to the 130s, accompanied by symptomatic hypocalcemia (calcium 6.5mg/dL). Initial management involved intravenous calcium gluconate and subsequent high-dose oral calcium (up to 10-16gm daily) with Calcitriol 1 mcg twice daily. Despite repletion, her calcium levels remained low on postoperative day 4 (calcium 6.8mg/dL, phosphate 1.9 mg/dL, magnesium 1.7mg/dL) with PTH at 131 pg/ml, confirming Hungry Bone Syndrome. After seven days of aggressive intravenous and oral calcium supplementation with high-dose Calcitriol, she was discharged with a calcium level of 8.9mg/dL. Discussion: Management of HBS following renal hyperparathyroidism surgery presents significant challenges due to associated comorbidities and other electrolyte abnormalities, with limited literature providing guidance on prevention and management. Our case demonstrated that early suspicion and aggressive management improved patient outcomes. Suspecting HBS in high-risk individuals and initiating interventions pre and post-surgery, including pre-treatment with calcitriol, bisphosphonates, and early aggressive intravenous calcium supplementation post-surgery, could potentially reduce morbidity and length of hospital stay.
Presentation: 6/1/2024
7434 Modulation of FGFR-FGF2-FGF23 Signaling Partially Rescues Osteoarthritis in Hyp Mice Homolog of Human X- Linked Hypophosphatemia
Authors: Hurley M M , Xiao L 
Published: October 2024

Abstract
Disclosure: M.M. Hurley: None. L. Xiao: None.
Human with X-linked hypophosphatemia (XLH) and its Hyp mice homolog develop several phenotypic abnormalities due to phosphate wasting mediated by abnormal Fibroblast Growth Factor Receptor-1 (FGFR1) and Fibroblast Growth Factor 23 (FGF23) signaling. XLH and Hyp mice also develop severe osteoarthropathy (OA) whose etiology is not fully defined. We previously reported that Fibroblast growth factor 2 (FGF2) regulates FGF23, specifically, mice overexpressing the high molecular weight FGF2 isoforms (HMWFGF2) in osteoprogenitors phenocopy Hyp mice including development of OA that worsens with age. Since we also reported that Hyp mice overexpress HMWFGF2 isoforms in osteoblasts and osteocytes, we examined whether the knee OA phenotype in Hyp mice was associated with aberrant FGFR1, FGF2, FGF23 signaling in knee joint articular cartilage and subchondral bone and whether in vivo FGFR tyrosine kinase inhibitor BGJ398 would modulate the OA phenotype in knee joints of Hyp mice. Ten weeks-old Control and Hyp mice were treated with Vehicle or BGJ398 for 12 weeks. Safranin-O staining of knee articular cartilage for proteoglycan revealed decreased staining in Hyp vehicle-treated mice that was partially restored to the cartilage thickness of Control mice in the Hyp-BGJ398-treated group. Significantly increased degradative enzyme matrix metalloproteinase-13 (MMP-13) in Hyp vehicle-treated knee articular cartilage was significantly reduced by BGJ398. Immunostaining revealed significantly increased phosphorylated FGFR1, FGF2 and FGF23 in both articular cartilage and subchondral bone. While BGJ398 significantly reduced immunostaining for phosphoFGFR1 and FGF2 in both articular cartilage and subchondral bone, it significantly reduced FGF23 in subchondral bone but not in articular cartilage. Significantly increased phospho-ERK1/2 labeling in Hyp-vehicle treated articular cartilage was partially rescued by BGJ398. This study demonstrates that increased FGFR1/FGF2 signaling contributes to OA in Hyp mice that can be partially rescued by FGF receptor inhibitor via reduction in MAPK signaling.
Presentation: 6/1/2024
6577 National Trends in Fragility Hip Fractures Among Community Dwelling Women With Low Femoral Neck Bone Mineral Density
Authors: Atri Avica , Anastasopoulou Catherine 
Published: October 2024

Abstract
Disclosure: A. Atri: None. C. Anastasopoulou: None.
Introduction: Fragility hip fractures are a major public health burden and are considered a good measure of the quality of healthcare. However, contemporary trends in fragility hip fractures in women with low femoral neck bone mineral density (BMD) in the United States are not known. Methods: We used data from the National Health and Nutrition Examination Survey (NHANES) for the years 2009-10, 2013–14 and 2017–18 to include U.S. women aged ≥ 60 years with bone mineral density (BMD) T score ≤ -1 at the femur neck, which was measured by dual energy x-ray absorptiometry (DEXA) on Hologic Discovery Model A Densitometers (Hologic, Inc., Bedford, Massachusetts). Fragility fracture at the hip was defined as self-reported hip fracture resulting from a fall from standing height or less. Participants with missing BMD and fracture data were excluded. ANOVA was used for comparing means. The Cochran-Armitage test was utilized for trend analysis. Results: Overall, in women aged ≥ 60 years with femoral neck T score ≤ -1, the average age of women of low BMD decreased from 71(±7.2) years to 69.6 (±6.7) years, whereas the mean T-score modestly worsened from – 1.96 (±0.62) to -2.04 (±0.77) from 2009-10 to 2017-18. Similarly, the prevalence of women with T score ≤ -2.5 increased from 18.1% to 21.3%. We also found no significant change in proportion of women who reported treatment for osteoporosis (2009-10: 19.8%, 2013-14: 18.5%, 2017-18: 19.7%; p trend = 0.052). However, proportion of women who experienced fragility hip fractures decreased significantly (2009-10: 2.4%, 2013-14: 1.5%, 2017-18: 1.2%; p trend = 0.001). The mean age of index fragility hip fracture was 70.6 years in 2009-10, 68.3 years in 2013-14 and 71.7 years in 2017-18 (p = 0.001). Age stratified analysis showed a decreasing trend in proportion of women ≥ 80 years who experienced their index fragility hip fracture (2009-10: 25.9%, 2013-14: 14.7%, 2017-18: 15%; p trend = 0.001) and 70-79 years (2009-10: 40.9%, 2013-14: 21.1%, 2017-18: 35.8%; p trend = 0.001), while an increasing trend was seen in women 60–69 years (2009-10: 33.2%, 2013-14: 64.2%, 2017-18: 49.2%; p trend = 0.001). Discussion In this nationally representative cohort of community-dwelling US women with a low femoral neck BMD, we found a 50% decrease in burden of fragility hip fractures over a 10-year period from 2009-10 to 2017-18. This trend was observed despite worsening mean femoral neck T-scores, T score ≤ -2.5, and similar rates of osteoporosis treatment. Interestingly, the proportion of women who experienced their index fragility hip fracture showed a declining trend among the 70-79 years and ≥ 80 years age-groups. This change may be due to increasing awareness and utilization of measures to decrease falls such as exercise, nutrition, health education and environment modifications targeted towards the elderly population.
Presentation: 6/2/2024
7752 Navigating Hypercalcemia in Pregnancy: A Case Report
Authors: Gabbay Jacob , Steinmetz-Wood Samantha 
Published: October 2024

Abstract
Disclosure: J. Gabbay: None. S. Steinmetz-Wood: None.
Introduction: Primary hyperparathyroidism (PHPT) in pregnancy is rare but presents many diagnostic and therapeutic challenges. Prompt diagnosis and treatment are important due to associated maternal and fetal risks, however evaluation of urine calcium to differentiate from Familial Hypocalciuric Hypercalcemia (FHH) becomes less reliable due to physiologic changes in pregnancy, sestamibi scans. CT scans require radiation, parathyroidectomy introduces surgical risk, and medical alternatives like bisphosphonates can interfere with fetal skeletal development. Clinical Case: A 24-year-old woman who presented to the emergency room for progressive nausea and abdominal pain was found to be pregnant with elevated serum calculated calcium to 11.4 mg/dL (2.84 mmol/L). She had a history of renal stones, longstanding hypercalcemia of unknown etiology and a remote family history of parathyroid “issues”. Follow up laboratory work showed a PTH of 75.8 pg/ml (8.04 pmol/L) with an elevated 24-hour urine calcium and a low 25OH vitamin D. Given her history of kidney stones and overt symptoms it was our clinical judgement that this was not a case of FHH. She was started on IV fluids twice weekly. After an unrevealing neck ultrasound, an MRI neck showed a 7 mm lesion along the posterior aspect of the left thyroid suggestive of a parathyroid adenoma. Sestamibi scan was avoided due to the risks of radiation to the developing fetus. Given the presumptive diagnosis of parathyroid adenoma, the lack of response to aggressive hydration, and the maternal and fetal risks of hypercalcemia during pregnancy, parathyroidectomy was pursued in her second trimester. Intra-operative inspection and biopsy showed the lesion to be only a lymph node. She underwent 4-gland exploration and the left inferior parathyroid gland, which appeared abnormal and enlarged, was removed. The intra-operative PTH dropped only from 98 to 80 (10.4 to 8.5 pmol/L). She otherwise had an unremarkable hospital course and at discharge her calcium was normal with an undetectable PTH, which can be an expected finding in pregnancy. On follow up she was feeling well with sustained normocalcemia and low PTH levels. Given the age at which her hyperparathyroidism started, she was referred to genetics for further evaluation. Clinical Lessons/Conclusion: There were significant biochemical and radiological limitations in the management of this case. Normally an inappropriately normal PTH with elevated serum calcium and normal urine calcium/creatinine clearance ratio confirms the diagnosis of PHPT, however in pregnancy it should be noted that FHH could also present with normal or elevated urine calcium due to absorptive hypercalciuria in pregnancy. Additional clinical history and reasoning was needed for management as well as a skilled surgeon, where preoperative localization was limited and was not ultimately helpful.
Presentation: 6/2/2024
7219 Ocular Findings in Jansen Metaphyseal Chondrodysplasia
Authors: Obiezu F , Pan K , Ninan A , Roszko K L , Weinstein L S , Ferreira C R , Gafni R I , Quadros Costa T Magone De , Collins M T , Jha S 
Published: October 2024

Abstract
Disclosure: F. Obiezu: None. K. Pan: None. A. Ninan: None. K.L. Roszko: None. L.S. Weinstein: None. C.R. Ferreira: None. R.I. Gafni: None. T. Magone De Quadros Costa: None. M.T. Collins: None. S. Jha: None.
Jansen Metaphyseal Chondrodysplasia (JMC) is an ultra-rare disorder, with only 30 patients estimated to have the disease globally. It is caused by heterozygous pathogenic variants in PTHR1 that result in constitutive activation of parathyroid hormone type 1 receptor (PTHR1) signaling. A detailed description of craniofacial manifestations of the disease is lacking. Here we characterize the ophthalmological manifestations in patients with JMC. Six patients (4 males, 67%) with genetically confirmed JMC underwent a detailed ophthalmological evaluation, spectral-domain optical coherence tomography (OCT), craniofacial CT and 18F-NaF PET/CT scans. Median age at the time of the visit was 27.5 [IQR: 29] years. On physical examination, all patients were noted to have widely spaced eyes; 5 of the 6 had down slanted palpebral fissures, proptosis, or ptosis. Two patients had incomplete or defective closure of the eyelids (lagophthalmos), of which one had a history of progressive right facial nerve palsy with profuse epiphora. The second patient had central visual field defects, bilateral moderate optic disc pallor and bilateral retinal nerve fiber layer (RNFL) atrophy on OCT exam with bilateral optic canal narrowing on CT. Notably, comparison of these findings with a prior scan performed 5 years earlier showed progressive decrease in RNFL bilaterally. This patient had a history of prolonged intravenous bisphosphonate therapy, initiated in infancy for hypercalcemia and continued for over a decade. A third patient had normal vision, subtle temporal pallor of the optic nerve heads on dilated fundus exam, normal average RNFL, but decreased retinal ganglion cell layer analysis (GCA) on OCT. GCA was decreased in 4 of the 6 patients compared to age-matched reference range indicating a chronic optic nerve atrophic process. These data represent the first comprehensive report of the ophthalmologic findings in a cohort of patients with JMC. They demonstrate that patients with JMC have significant eye findings that appear to be more prevalent and pronounced with age. This suggests age-related, progressive optic neuropathy, which can be assessed by demonstrating OCT retinal GCA and RNFL loss and, may be a feature of JMC. The benefit and effect of long-term bisphosphonate therapy in patients with JMC remains unclear. Patients with JMC should undergo regular ophthalmologic examination including optic nerve OCT, visual field testing, and craniofacial imaging.
Presentation: 6/1/2024
12453 Osteoporosis Screening In A Primary Care Clinic: Barriers And Solutions
Authors: Laquidara Bethany M , Mistry Sohi , Fang Guo Ling , Groubert Jordan , Oravec Michael 
Published: October 2024

Abstract
Disclosure: B.M. Laquidara: None. S. Mistry: None. L. Guo: None.
Purpose/Objective: Osteoporosis is a prevalent bone disorder that affects over 10 million people in the United States. The US Preventive Services Task Force (USPSTF) recommends screening females aged 65 and older with a baseline DEXA scan and to screen postmenopausal females younger than age 65 who have an increased risk of osteoporosis. Despite these guidelines, the screening rate for osteoporosis remains very low. Our quality improvement project seeks to first identify at what rate eligible patients in our residency primary care clinic are being screened for osteoporosis and what barriers (patient, provider, or clinical factors) to screening may decrease this rate. Methods: We reviewed a random sample medical records of 300 female patients aged &gt;/= 50 years who visited our clinic within the last two years. We collected patient demographics, insurance status, presence of ≥1 risk factor of osteoporosis (fracture, heavy alcohol use, tobacco use, steroid use, BMI&lt;19), MyChart activity, provider training level, diagnosis code, and whether a baseline DEXA was ordered and/or completed. We compared patient characteristics by DEXA order status using descriptive statistics, and used multivariable regression models to determine odds of DEXA order and completion. Results: The patients who were at high risk for osteoporosis were more likely to have an order without completion (OR 6.11, p &lt;0.001). Increased age was associated with increased odds of having an order (OR 1.09, p&lt;0.001). Increasing BMI was associated with decreased odds of having an order. Black patients and current smokers were less likely to have a DEXA scan ordered and completed after controlling for age and other confounding factors (p= 0.002 and 0.001 respectively). Among the 96 patients who had a completed DEXA scan, 74 had osteoporosis. The only significant predictor for having osteoporosis was low BMI (OR 0.87%, p&lt;0.001). Conclusion: The results of this study suggest that while patients with a clinically high risk for osteoporosis are more likely to have an order placed for a DEXA scan, these patients often do not have a completed scan. Patients who have an ICD-10 diagnosis of high-risk for osteoporosis or osteoporosis in their electronic medical record are more likely to have both an ordered and completed scan. Utilizing this data, we will develop a variety of interventions such as a clinical didactic case for osteoporosis, a flow-sheet summary of proper osteoporosis screening and treatment initiation to be distributed in the clinic setting, and a short presentation during noon didactics where we review the proper screening method for osteoporosis. Following our intervention, we will re-examine the screening rate in our residency clinic to evaluate the effect of our intervention.
Presentation: 6/3/2024
12313 Parathyroid Carcinoma Presenting As Right Foot Pain And Swelling In A Young Male - A Case Report
Authors: Esclanda Sorsona Francis , Kristine Lopez Lizette 
Published: October 2024

Abstract
Disclosure: F.E. Sorsona: None. L. Lopez: None.
Parathyroid carcinoma is a rare cause of hyperparathyroidism that is challenging to diagnose. We report a case of parathyroid carcinoma with an unusual initial presentation of right foot pain and swelling in a young 26-year-old Filipino male. Physical examination revealed a palpable 1 x 1 cm mass with tenderness on his right foot. Initial work-up showed a persistently elevated serum ionized calcium (range: 1.7 - 2.19 mmol/L) with markedly high intact parathyroid hormone (1,890 pg/ml). A right foot x-ray revealed a lytic bone lesion on the 3rd metatarsal. Skeletal survey revealed diffuse lytic bone lesions. Comprehensive neck ultrasound showed a 4 x 1.6 x 2.5 cm complex nodule adjacent to the inferior pole of the left lobe of the thyroid gland with intralesional calcifications. A 4D CT scan showed a 3.3 x 2.2 x 2 cm hypervascular nodule inferior to the left thyroid lobe with early contrast washout, likely parathyroid in origin, and a possible brown tumor in the right fourth rib. Patient underwent parathyroidectomy with intraoperative PTH monitoring showing a marked reduction of intact PTH by 87% (235.9 pg/ml from 1,890 pg/ml), accompanied by reduction of serum ionized calcium. The histopathology reported parathyroid carcinoma highlighted by lymphovascular invasion, atypical round cells in sheets and nests, with enlarged, mildly pleomorphic, hyperchromatic nuclei and prominent nucleoli. Two months after surgery, normal serum ionized calcium was maintained with calcium supplementation with reported relief of right foot pain and swelling. The patient continues to follow up regularly for monitoring of treatment response.
Presentation: 6/2/2024