Calcium Supplementation Research Articles

Calcium Transport Activity of UV/H2O2-Degraded Fucoidans and Their Structural Characterization

Calcium-chelated polysaccharides have been increasingly considered as promising calcium supplements. In this study, degraded fucoidans (DFs) with different molecular weights (Mws) were prepared after UV/H2O2 treatment; their calcium-chelating capacities and intestinal absorption properties were also investigated. The results showed that the calcium-chelating capacities of DFs were improved with a decrease in Mw. This was mainly ascribed to the increased carboxyl content, which was caused by free-radical-mediated degradation. Meanwhile, the conformation of DF changed from a rod-like chain to a shorter and softer chain. The thermodynamic analysis demonstrated that DF binding to calcium was spontaneously driven by electrostatic interactions. Additionally, DF-Ca chelates with lower Mw showed favorable transport properties across a Caco-2 cell monolayer and could effectively accelerate the calcium influx through intestinal enterocytes. Furthermore, these chelates also exhibited a protective effect on the epithelial barrier by alleviating damage to tight junction proteins. These findings provide an effective free-radical-related approach for the development of polysaccharide-based calcium supplements with improved intestinal calcium transport ability.

Beta thalassemia minor: a potential risk factor for osteopenia and osteoporosis

A 74-year-old male patient with beta thalassemia minor presented in 2022 for a follow-up of osteoporosis diagnosed prior to 2004. At the time of presentation, his medical history included: radiation exposure to his head and neck, goiter, prostate cancer status post resection in 2019 without a history of anti-androgen therapy, and atrial fibrillation, for which he had been prescribed apixaban since 2021. Treatment with risedronate occurred from approximately 2004 to about 2011, with improvement in bone density to osteopenia. He had also taken vitamin D and calcium supplementation and engaged in regular weight-bearing exercise. The patient had no other known risk factors for decreased bone mineral density preceding the onset of his osteoporosis, and a previous workup for secondary causes of his osteoporosis etiology proved negative. We propose that beta thalassemia minor is potentially a risk factor for osteopenia and osteoporosis, and that bisphosphonates can be considered for management when therapeutic intervention is indicated. Even in the absence of other known risk factors, clinicians should consider periodically screening beta thalassemia minor patients with DXA for evaluation of bone health.

Augmenting Rice Defenses: Exogenous Calcium Elevates GABA Levels Against WBPH Infestation

This study investigates the impact of exogenous calcium and gamma-aminobutyric acid (GABA) supplementation on rice growth and stress tolerance under white-backed planthopper (WBPH) infestation. We evaluated several phenotypic traits, including shoot/root length, leaf width, tiller number, panicle length, and relative water content, alongside physiological markers such as oxidative stress indicators, antioxidant enzymes activities, hormonal levels, and amino acids biosynthesis. Our results indicate that WBPH stress significantly reduces growth parameters but calcium and GABA supplementation markedly enhance shoot length (by 26% and 36%) and root length (by 38% and 64%), respectively, compared to WBPH-infested plants. Both supplementations also reduced oxidative stress, as evidenced by decreased H2O2 and O2•− levels and a lower electrolyte leakage. Notably, calcium and GABA treatments increased antioxidant enzyme activities, with GABA boosting catalase (CAT) activity by 800%, peroxidase (POD) by 144%, and superoxide dismutase (SOD) by 62% under WBPH stress. Additionally, calcium and GABA enhanced the accumulation of stress hormones (abscisic acid ABA) and salicylic acid (SA) and promoted stomatal closure, contributing to improved water conservation. This study reveals that calcium regulates the GABA shunt pathway, significantly increasing GABA and succinate levels in both root and shoot. Furthermore, calcium and GABA supplementation enhance the biosynthesis of key amino acids and improve ion homeostasis, particularly elevating calcium (Ca), iron (Fe), and magnesium (Mg) levels under WBPH stress. Overall, this study highlights the potential of exogenous calcium and GABA as effective strategies for enhancing rice plant tolerance to WBPH infestation by modulating various physiological and biochemical mechanisms. Further research is warranted to fully elucidate the underlying mechanisms of action.

RESPONSE OF SUMMER TOMATO WITH EXOGENOUS APPLICATION OF SALICYLIC ACID AND CALCIUM

A pot experiment was carried out at Horticulture Farm, Sher-e-Bangla Agricultural University, Dhaka May to September, 2016 to evaluate the performance of summer tomato production with the supplementation of salicylic acid (SA) and calcium (Ca). The experiment consisted of two factor. Four different levels of SA (S1 = 0 mM SA, S2 = 0.3 mM SA, S3 = 0.6 mM SA, S4 = 0.8 mM SA) and three levels of Ca (C1 = 0 mM Ca, C2 = 4 mM Ca, C3 = 8 mM Ca). Both morphological traits and yield of summer tomatoes were significantly affected by the application of SA and Ca. Exogenous application of SA and Ca influenced the growth including plant height, leaf number, branch number, yield contributing characters and yield. The combined supplementation of 0.8 mM SA and 8 mM Ca resulted the highest yields (0.8 kg/plant) where lowest one (0.3 kg/plant) was recorded from the control treatment (without SA and Ca). These results suggest that SA and Ca can improve the growth and yield of tomatoes during the summer season by alleviating the detrimental effects of extreme heat in the summer.

Association between dietary supplements and frailty by sex: a cross-sectional study in South Korea

Abstract Background Evidence regarding the benefits of dietary supplements against frailty is lacking. Therefore, we aimed to examine the association between the use of dietary supplements and frailty. The analyses were stratified by sex to consider the sexual dimorphism in frailty. Methods This study used national, cross-sectional survey data from South Korea, namely the Korea National Health and Nutrition Examination Survey (KNHANES, 2018-2020). Adults aged 50 years were included. Data for up to four supplements were collected for each participant. A 46-item frailty index was constructed to assess frailty. All percentages (%) were weighted to represent the national population. The association between the use of dietary supplements and frailty was investigated using a linear regression analysis with socioeconomic/lifestyle factors and the amount of nutrient intake from diet included as covariates. Results Of the included 27,384 older adults, 57.28% were women. The proportion of supplement users was significantly higher in women (64.31% vs. 77.71%, p < 0.001). Any supplement use was negatively associated with frailty (B = -0.015, p < 0.001), and the association was more significant in women (Any supplement use * women: B = -0.012, p = 0.002). From the multivariable regression analysis stratified by sex, the use of red ginseng (men: B = -0.019, women: B = -0.015) and calcium (B = -0.027, women: B = -0.012) were negatively associated with frailty in both sexes while the statistical significance for vitamin C was found only in men (B = -0.020) (all p < 0.05). Conclusions Our findings demonstrated a significant negative association between the use of dietary supplements and frailty. The associations varied by type of supplements and by sex. The findings should be validated using prospective data. Key messages • Red ginseng and calcium supplements were negatively associated with frailty in both sexes. • We assessed frailty using frailty index which highlights the potential role of dietary supplements beyond the context of physical or musculoskeletal function.

Preoperative Calcium or Vitamin D Supplement in Thyroidectomy: A Systematic Review and Meta-Analysis.

The objective of this systematic review and meta-analysis was to assess the role of preoperative calcium and vitamin D supplementation in patients who underwent total thyroidectomy. The search for randomized controlled trials was performed in the OVID Medline and Embase databases. The last search was made on September 16, 2024. Three independent reviewers evaluated full-text articles from relevant reports based on eligibility criteria. The quality of the included studies was assessed by two reviewers according to the ROB 2 tool. This systematic review and meta-analysis considered 13 studies with 1504 participants. There were positive results in treatment outcomes including the mean postoperative calcium level (MD, 0.30 mg/dL: 95% CI, 0.15 to 0.44); the 48 h of postoperative hypocalcemia (OR, 0.41; 95% CI, 0.27 to 0.62); the postoperative symptomatic hypocalcemia (OR, 0.38; 95% CI, 0.24 to 0.62); the IV calcium supplementation (OR, 0.32; 95% CI, 0.18 to 0.58); and length of hospital stays (MD, -0.29; 95% CI, -0.51 to -0.07) as compared to the control group. Readmission rates showed no significant differences between the groups (OR, 0.15; 95% CI, 0.01 to 3.08). Preoperative calcium and vitamin D supplementation in patients who underwent total thyroidectomy results in reduction of postoperative symptomatic hypocalcemia. The finding is critical because it offers a feasible and effective solution that could improve patient care while potentially reducing the burden of numerous blood tests during the postoperative period. This systematic review protocol was registered with PROSPERO (registration number CRD42021278859). Level 1 Laryngoscope, 2024.

Knowledge, attitude, and practice regarding the prevention of osteoporosis among middle and old-aged women of Kirtipur Municipality, Nepal.

Osteoporosis is a major public health problem that can lead to physical disability, working performance limitations, decreased self-sufficiency, and increased hospitalization and mortality rates. People are unaware of osteoporosis, and it is often undiagnosed until fractures occur. Limited studies have been conducted to determine the knowledge, attitude, and practice regarding osteoporosis among middle-aged women in Nepal. This study aimed to determine existing knowledge, attitude, and practice towards osteoporosis among middle and old-aged women in Nepal. A cross-sectional study was conducted among the selected wards of Kirtipur Municipality to recruit 405 participants. Participants were selected using a stratified random sampling technique. Face-to-face interviews using a structured questionnaire were performed to collect the data. Frequencies, percentages, mean, and standard deviation were used to describe the characteristics of participants. Multivariate logistic regression was used to determine the factors associated with knowledge, attitude, and practice regarding osteoporosis. Pearson's correlation coefficient was used to determine the correlation between knowledge, attitude, and practice regarding osteoporosis. The mean ± SD age of the participants was 46.2 ±9.1 years. Nearly half of the participants (48.8%) had good knowledge, while 57.7% and 51.8% had positive attitudes and good practices regarding osteoporosis, respectively. The occupation and income of the participants were statistically significant and associated with the knowledge level. Meanwhile, age, ethnicity, education, occupation, and monthly household income were associated with attitude level. With a good practice level, ethnicity, family type, and education were statistically significant. The knowledge-attitude (rka = 0.093, p < 0.05), attitude-practice (rap = 0.171, p < 0.001), and knowledge-practice (rkp = 0.274, p < 0.001) for osteoporosis were positively correlated. The study found that still around half of the middle and old-aged women had poor knowledge, negative attitudes, and poor practices regarding osteoporosis. Moreover, it highlighted inadequate dietary practices, such as low consumption of milk, vegetables, fruits, and calcium supplements among women, indicates are at greater risk of osteoporosis. The study emphasized the need for community-based awareness programs for the target population such as housemakers, and lower-income groups, to prevent osteoporosis among women.

Environmental triggers of pemphigus vulgaris and bullous pemphigoid: a case control study.

Previous case-control studies have suggested that environmental factors including exposure to pesticides and organic materials, diet and medications have an important role in the pathogenesis of pemphigus vulgaris. These studies lacked geographical population controls and had less than three controls per case. To identify environmental and occupational risk factors associated with the development of pemphigus vulgaris (PV) and bullous pemphigoid (BP). Cases were patients with PV (n = 25) and BP (n = 29) recruited from 2009 to 2017. Controls for PV (n = 72) and BP (n = 84) were recruited from the general population via electoral commission matching, matched for age, sex, residential location, and ethnicity. Data about demographics, environmental exposures and occupational exposures, was collected using a structured questionnaire. Conditional logistic regression analysis was undertaken using SPSS software to identify significant variables. Significant factors associated with PV included the daily consumption of leeks (odds ratio (OR) 3.6; p = 0.025), mustard oil (OR = 4.4; p = 0.049), tomatoes (OR = 4.735; p = 0.032), multivitamins (OR 3.6; p = 0.009), alcohol (0.039), and calcium supplements (OR = 44, p < 0.001). Other associated factors included the number of lifetime sunburns (p = 0.019), high levels of mental stress (p < 0.001), and the use of lime household cleaning products (p < 0.001), Significant factors associated with BP included the daily consumption of green or herbal tea (OR = 3.7; p = 0.004), fish oil (OR = 5.7; p < 0.001), calcium supplements (OR = 6.1; p < 0.001), multivitamins (OR = 2.6; p = 0.043), and glucosamine (OR = 3.0; p = 0.046). The use of lime household cleaning products (p < 0.001) and high levels of mental stress (p = 0.007) were also associated with BP. Dietary factors containing thiol groups such as leeks, tomatoes, and mustard oil may be potential triggers for PV. High levels of mental stress, the use of supplementary medications such as calcium and multivitamins, and chemical cleaning products containing lime may be associated with an increased risk of developing both PV and BP. Lifestyle changes should be part of routine management for these patients.

Grouper bone nano-calcium and substitution long-chain triglyceride (LCT) into medium-chain triglyceride (MCT) enhanced calcium bioavailability and rat’s bone density

BACKGROUND: The most effective strategy to prevent osteopenia or osteoporosis in the old life is to consume an adequate amount of calcium from childhood through adulthood. OBJECTIVE: This study compared the bioavailability of CaCO3 which is the standard non-dairy calcium supplementation with grouper bone nano-calcium (GBN) combined with various percentages of Long-Chain Triglyceride (LCT) into Medium-Chain Triglyceride (MCT) on calcium bioavailability and rat’s bones density. METHODS: This study was carried out during the rat’s growth period, from the weaning until the rats reached 16 weeks. Thirty-five weaned rats were separated into seven groups and fed varied feeds for 12 weeks. The seven groups of feed were (1) CCa: standard feed AIN-93G, (2) C0: standard calcium deficient feed (without calcium), (3) G0: GBN + MCT:LCT 0 : 100%, (4) G25: GBN + MCT:LCT 25 : 75%, (5) G50: GBN + MCT:LCT 50 : 50%, (6) G75: GBN + MCT:LCT 75 : 25%, and (7) G100: GBN + MCT:LCT 100 : 0%. Parameters observed were serum levels of calcium, phosphorus, and alkaline phosphatase, femur bone characteristics, bone microarchitecture by histomorphometry, micro computed-tomography (μCT), and mechanical strength. RESULTS: The CCa and G100 groups had the best dietary results based on all parameters. The G100 group was superior to CCa in calcium and phosphorus bioavailability, rat’s bone strength and density. CONCLUSIONS: G100: GBN + MCT:LCT 100 : 0% group feed beneficially affected the bioavailability of calcium, was letting he rat’s bones to develop properly, had high density, and been strong throughout the growth phase.

Sex-Specific Association Patterns of Bone Microstructure and Lower Leg Arterial Calcification

In conversations about bone loss and the importance of calcium homeostasis, patients frequently inquire about the association with arterial calcifications. Although a relationship between bone loss and the occurrence of vascular calcifications is suspected, it is not yet fully investigated and understood. This study aims to analyze associations between bone mineralization, structure, and vascular calcification at the lower leg in patients with low bone mineral density in HR-pQCT. We retrospectively analyzed 774 high-resolution quantitative computed tomography (HR-pQCT) scans of the distal tibia for the presence of vascular calcifications. After sex-specific propensity score matching for age and BMI to account for confounders, 132 patients remained for quantification of bone microstructure, bone density, lower leg arterial calcification (LLAC), and laboratory parameters of bone turnover. The interactions between bone parameters and vascular calcification were quantified by regression analyses. The calcium metabolism was not different between individuals with and without LLAC, nor oral calcium supplementation. Female patients with LLAC had a higher cortical perimeter (p = 0.016) compared to female patients without LLAC, whereas male patients with LLAC had lower cortical pore diameter than male patients without LLAC (p = 0.027). The appearance of LLAC was sex specifically associated with bone parameters. In female patients, only plaque density was associated with HR-pQCT bone parameters and age, whereas in male patients, plaque volume was associated with HR-pQCT parameters of the distal tibia. Female patients exhibit an increasing plaque density depended on age and trabecular thinning. Decreasing cortical pore diameter and trabecular number along with increasing bone mineralization are linked to increasing plaque volume in male patients.

Hypoparathyroidism: an update on new therapeutic approaches.

Hypoparathyroidism is a rare endocrine disease characterized by insufficient parathyroid hormone (PTH) secretion by the parathyroid glands, leading to hypocalcemia. In contrast to most hormone deficiencies for which hormone replacement is currently the mainstay of therapy, hypoparathyroidism has conventionally been treated with calcium supplements and active analogs of vitamin D. Although the advent of a replacement therapy with 1-34 and 1-84 PTH represented a major step in the therapeutic history of hypoparathyroidism, several new molecules and different management strategies have recently been developed. This review investigates the therapeutic approaches currently under investigation for the treatment of hypoparathyroidism. Clinical trials results have been considered and discussed.

12520 Preliminary Findings From An Ongoing Open-label Phase 2 Study Demonstrate That The Calcilytic Encaleret Can Improve The Relationship Between Blood And Urinary Calcium In Individuals With Post-surgical Hypoparathyroidism

Abstract Disclosure: I.R. Hartley: Research Investigator; Self; Calcilytix Therapeutics, Inc. R.I. Gafni: Research Investigator; Self; Calcilytix Therapeutics, Inc. K.L. Roszko: Research Investigator; Self; Calcilytix Therapeutics, Inc. X. Li: None. E.A. Ferguson: Research Investigator; Self; Calcilytix Therapeutics, Inc. C.A. Moore: Research Investigator; Self; Calcilytix Therapeutics, Inc. K.A. Pozo: Research Investigator; Self; Calcilytix Therapeutics, Inc. K.T. Ampuero: Research Investigator; Self; Calcilytix Therapeutics, Inc. A.V. Sridhar: Employee; Self; Calcilytix Therapeutics, Inc. A.S. Mathew: Employee; Self; Calcilytix Therapeutics, Inc. M. Roberts: Employee; Self; Calcilytix Therapeutics, Inc. S.H. Adler: Employee; Self; Calcilytix Therapeutics, Inc. E.F. Nemeth: Consulting Fee; Self; Calcilytix Therapeutics, Inc. M.T. Collins: Research Investigator; Self; Calcilytix Therapeutics, Inc. Parathyroid hormone (PTH) and the calcium-sensing receptor (CaSR) are the primary regulators of blood and urinary calcium. The independent contributions of PTH and the CaSR on renal calcium handling are not well understood, largely due to their intertwined physiology. In individuals with functioning parathyroid tissue, calcilytics (negative modulators of the CaSR) increase PTH secretion and decrease urinary calcium excretion, leading to increased blood calcium levels. We hypothesized that calcilytic administration to individuals with post-surgical hypoparathyroidism (PSH) may reveal the PTH-independent effects of CaSR modulation on renal calcium handling and clarify the potential therapeutic role of calcilytics in PSH. Four women (26-69y) with PSH enrolled in an ongoing, open-label, phase 2, proof-of-principle study of encaleret, an oral investigational calcilytic (NCT05735015). Encaleret 162 mg was administered every 12 hours for up to 10 doses. Calcitriol was discontinued one day prior to the first dose of encaleret. All participants received calcium supplementation initially. To maintain eucalcemia, 1 participant discontinued calcium supplementation and 3 required re-initiation of low-dose calcitriol (0.25 mcg daily). Results are presented as mean (range) of fasting baseline pre-dose levels compared to fasting levels 12 hours after the last dose of encaleret. Fractional excretion of calcium (FECa), a measure of renal calcium handling that quantifies the relationship between blood and urinary calcium, decreased by 52% (34-78). Albumin-corrected blood calcium increased from 8.4 mg/dL (range 8.1-8.6; nl 8.4-10.2) to 9.3 (8.6-10.7). Urinary calcium excretion decreased from 348 mg/day (range 204-501; nl &amp;lt;250) to 169 (76-350), with normalization in 3 participants and a 30% decrease in the fourth. Baseline PTH of 7.4 pg/mL (range 4.6-10.1; nl 15-65) transiently increased 30 minutes after the first dose to 13.0 (4.5-18.1), then returned to near baseline levels. Bone turnover markers were normal and did not change on encaleret. There were no serious adverse events reported. The only treatment-related adverse events (AEs) were mild hypercalcemia causing headache in 1 participant. Her blood calcium levels continued to be mildly elevated for 60 hours after the last dose of encaleret even after calcium and calcitriol supplementation was discontinued. Despite elevated blood calcium, her 24-hour urine calcium remained &amp;lt;200 mg/day. Encaleret reduced FECa in the first four participants with PSH, improving the relationship between blood and urinary calcium. These preliminary results from this Phase 2 study support continued evaluation of encaleret as an orally administered therapy for the treatment of patients with PSH. Presentation: 6/1/2024

6409 Successful Treatment Of Severe Ectopic ACTH-dependent Cushing’s Syndrome With Osilodrostat

Abstract Disclosure: K.A. Lee: None. C. Mendes Pessoa: None. W. Huang: Consulting Fee; Self; WH, Honoraria from Consulting and Speaking received from Recordati Rare Disease. Background: Cushing’s syndrome due to ectopic ACTH secretion is rare and may progress rapidly, making treatment very challenging. Previous case reports have described therapeutic options including adrenal steroidogenesis inhibitors, bilateral adrenalectomy (BAL), and adrenal embolization with success. Clinical Case: A 27-year-old woman with metastatic neuroendocrine tumor presented with sudden onset and rapidly progressing symptoms of fatigue, muscle weakness, acne and weight gain within two weeks. Laboratory findings confirmed severe Cushing’s syndrome due to ectopic ACTH secretion: AM cortisol 173.4 µg/dL (5-25), ACTH 1425 pg/mL (7.2-63.3), 24 hour urine cortisol 29,498 mcg/24hr (4-50), DHEA-Sulfate 1314 µg/dL (65 - 380), and testosterone 133 ng/dL (0-100). She was also found to have severe hypokalemia, hypocalcemia and hyperglycemia (despite an HbA1C of 6.2 at 2 weeks before presentation). CT- scan showed diffuse thickening of the bilateral adrenal glands. Due to widely metastatic disease in the peritoneum, BAL was considered non-feasible. The patient was admitted to hospital and initiated on osilodrostat at 20mg twice daily (after correction of hypokalemia) with close monitoring of her electrolytes, cortisol, EKG and steroid withdrawal symptoms. There was a rapid improvement of cortisol levels in response to osilodrostat. During treatment, she developed steroid withdrawal symptoms for which she was started on medium dose hydrocortisone. Bilateral adrenal arterial embolization was attempted but ultimately needed to be converted to right only adrenal gland embolization due to a hypertensive urgency and difficulty with catheterization. Her symptoms of Cushing’s syndrome significantly improved with the treatment. During her hospitalization, her hypokalemia was managed with spironolactone and potassium supplement, hypocalcemia with calcium supplement, and hyperglycemia with basal and bolus insulins. With significant improvement of cortisol levels, her hypocalcemia and hyperglycemia resolved and required no further treatment. Her potassium levels normalized and spironolactone was stopped. She remains on potassium supplement to keep K level at upper half of normal range to avoid long QTc. After discharge, her morning cortisol levels (before morning dose of hydrocortisone) continued to decrease and her osilodrostat dose was gradually tapered to 5mg once daily at night. Hydrocortisone was continued as part of the block-and-replace regimen. Conclusion: This case described a unique sudden onset and rapid progression of ectopic ACTH dependent Cushing’s syndrome and successful utilization of a block-and-replace approach by using the steroidogenesis inhibitor osilodrostat in prompt control of the hypercortisolism and related comorbidities. We also explored the feasibility of adrenal embolization for definitive management in the context of unfeasible BAL. Presentation: 6/2/2024

8472 A Little Too Much Of Tums: A Unique Presentation Of Milk Alkali Syndrome

Abstract Disclosure: Z. Al-Hiti: None. A. Misbah: None. Milk-Alkali Syndrome is characterized by a triad of hypercalcemia, metabolic alkalosis, and renal dysfunction. Historically associated with the excessive consumption of milk and alkali-containing antacids, it has re-emerged in recent years due to the widespread use of calcium and vitamin D supplements. It primarily results from an imbalance between calcium intake and renal excretion, leading to elevated calcium levels in the bloodstream. We present a case of milk-alkali syndrome with persistent renal dysfunction after normalizing calcium levels. We present the case of a 65-year-old male who presented to the emergency department with generalized weakness, poor oral intake, and confusion for 3 days. He was noted to have been more adherent with taking his prescribed medications over the last 2 weeks, which include calcitriol 0.5 mcg BID, calcium acetate 667 mg TID, and calcium carbonate 800 mg TID. On admission, he was afebrile and hemodynamically stable. . On examination, he had dry mucous membranes. He had no focal neurological deficits but he was confused and lethargic, and was only oriented to self. Other examination was noncontributory. Complete blood count and urinalysis were largely unremarkable. Chemistry demonstrated an elevated calcium level of 16.0 (8.3-10.6 mg/dL), ionized calcium of 7.3 (4.6-5.3 mg/dL), sodium of 134 (135-145 mmol/L), potassium of 5.4 (3.5-5.1 mmol/L), high phosphorus of 5.3 (2.4-5.1 mg/dL), and bicarbonate of 36 (20-31 mEq/L). Creatinine was elevated at 2.9 (0.6-1.1 mg/dL) from baseline of 1.3 to 1.4 mg/dL, and he had a BUN of 40(9-23 mg/dL). Venous blood gas showed a pH of 7.54( 7.32-7.42), pCO2 of 56 (40-52 mm Hg), and bicarbonate of 38 (23-28 mEq/L), indicating metabolic alkalosis. TSH was elevated at 36.15 (0.55- 4.78 uIU/mL) with a level of 140 two weeks back. Chest X-ray, renal ultrasound and CT head all showed no acute disease. Further work-up revealed a low PTH level of 6.3 (18.4-80 pg/mL), normal PTHrP level and 25-OH Vitamin D. There was no monoclonal gammopathy. Management included aggressive IV fluid resuscitation and IV calcitonin. However, no zoledronic acid was given due to a history of parathyroidectomy and risk of hypocalcemia. His serum calcium improved and eventually normalized. His confusion resolved. However, his creatinine and BUN increased to 3.4 mg/dL and 77, respectively, and did not improve to his baseline. This case highlights the importance of recognizing Milk-Alkali Syndrome as a potential consequence of over-the-counter calcium supplementation and highlights the potential for acute kidney injury which could be irreversible. Healthcare providers should be vigilant in identifying patients at risk, which includes older patients and patients with chronic kidney disease. Early recognition and appropriate management are crucial to prevent further renal deterioration and improve outcomes in individuals with Milk-Alkali Syndrome. Presentation: 6/2/2024

12313 Parathyroid Carcinoma Presenting As Right Foot Pain And Swelling In A Young Male - A Case Report

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

7388 Rare Case of Mediastinal Parathyroid Carcinoma

Abstract Disclosure: Y. Esaki: None. J. Moalem: None. A. Israel: None. I. Shafiq: None. Introduction: Parathyroid carcinoma accounts for 1% of primary hyperparathyroidism with an estimated prevalence of 0.005% of all cancers. Ectopic locations of parathyroid tumors have been found in 6-16% of cases, most commonly in the thyroid, the thymus, or behind the esophagus. Parathyroid carcinoma is rarely found in the mediastinum and only 30 cases have been reported in the literature. Clinical Case: A 68-year-old male without significant past medical history was evaluated by his primary care physician for constipation, polyuria and 20 lb weight loss over the past year. He presented to the hospital after blood work revealed serum calcium of 13.5 mg/dl (8.6-10.2 mg/dl). Initial hospital workup demonstrated serum calcium 12.9 mg/dl, phosphorus 2.6 mg/dl (2.7-4.5 mg/dl), 25-OH vitamin D 21 ng/ml (30-60 ng/ml), 1,25-(OH)2 vitamin D 143.0 pg/ml (19.9-79.3 pg/ml), PTH-related protein &amp;lt; 2.0 pmol/L (0.0-2.3 pmol/L) and PTH 1,250.0 pg/ml (15.0-65.0 pg/ml). CT scan revealed a 3.5 cm x 2.6 cm heterogeneous right paratracheal soft tissue mass with areas of calcifications with mass effect on SVC. Thyroid ultrasound showed multinodular thyroid tissues with a left 1.1 cm heterogeneous solid nodule along the mid posterior aspect as well as a 0.5 cm hypoechoic lesion inferior to the left lobe. Sestamibi scan demonstrated a large area of increased uptake corresponding to the mass seen in the superior mediastinum on CT imaging. He underwent neck exploration and left hemithyroidectomy as well as median sternotomy with resection of the paratracheal mass. Intraoperative PTH decreased from the baseline of 1,177.0 pg/ml to 65.6pg/ml following the removal of the paratracheal mass. The final pathology of right anterior mediastinal mass was consistent with a 5 cm parathyroid carcinoma with angioinvasion, intermediate lymphatic invasion, invasion into adjacent structures, and Ki67 proliferative index focally &amp;gt; 5%. His post-operative course was complicated by hypocalcemia, which improved with treatment with calcitriol and calcium supplementation. He declined the genetic testing. His calcium and parathyroid hormone have remained in the normal range after 1 year. Conclusion: This case illustrates a rare case of parathyroid carcinoma found in the mediastinum. It is important to recognize that parathyroid carcinoma can present in ectopic locations including the mediastinum, as this can affect the preoperative investigation and management. Fine needle biopsy (FNA) prior to the initial operation is not recommended as it is difficult to differentiate the parathyroid carcinoma from benign disease based on FNA, and it may cause tumor rupture and seeding. Also, in the mediastinal parathyroid carcinoma, localization of the lesions including the size and invasiveness is critical in order to allow for radical surgery. Presentation: 6/3/2024

7172 Osteoporosis Associated with Antiretroviral Therapy - Case report

Abstract Disclosure: C.E. Guillen Lopez: None. L.A. Sanchez Ato: None. A. Patel: None. A. Molkina: None. T. Ayub: None. L. Robles: None. A. Arce Gastelum: None. Osteoporosis presents a substantial public health challenge, contributing significantly to morbidity and mortality through fractures. While postmenopausal osteoporosis is common, secondary osteoporosis affects a significant number of patients, including over 30% of postmenopausal and 50-80% of men. People living with HIV (PLWH) experience age-related medical comorbidities earlier and more extensively than those without HIV. The compromised bone health in PLWH is attributed to factors associated with the virus, antiretroviral therapy (ART) side effects, and health disparities such as inadequate nutrition, low body weight, hypogonadism, vitamin D deficiency, and increased recreational substance use. More recently, it has become apparent that vertebral fractures are more common in PLWH, with a prevalence of 11.1% and a 2.30-fold more significant risk than the general population. Low bone mass density (BMD) is twice as common in PLWH, increasing to 3 times as common in PLWH on ART. ART initiation leads to transient bone loss with nucleotide reverse transcriptase inhibitors such as tenofovir disoproxil fumarate (TDF) and protease inhibitors, causing higher BMD loss. In contrast, integrase and specific reverse-transcriptase inhibitors have minimal adverse effects on BMD. The newer formulation, tenofovir alafenamide (TAF), is believed to have a more favorable impact on bone health than TDF. The repercussions of diminished bone health, particularly osteoporotic fractures, have significant medical and economic implications. They are leading to early mortality, disability, and a loss of independence. The HIV Medicine Association (HIVMA) and Infectious Diseases Society of America (IDSA) recommend BMD screening for all HIV-infected patients at 50 years. 58-year-old male PLWH reveals a history of osteoporosis with multiple spinal (L1, L4-5, S1) and bilateral wrist fractures on TDF for 15 years. The patient has been treated with bisphosphonates. Alendronate was initially prescribed, but due to acid reflux side effects, zoledronic acid was a better option. Despite various ART regimens, Dolutegravir/Lamivudine was started four years ago without further fractures. Recent bone density assessments showed improvement in the lumbar spine, returning to a normal range with a T-score of 0.6. However, the left femoral neck remains at -2.5, and the right femoral neck is at -2.2, showing minimal change. To enhance BMD in PLWH on ART, transitioning to alternatives with lower bone loss associations and using bisphosphonates as tolerated are suggested. As the HIV-infected population ages, proactive screening for low BMD is vital to manage evolving health needs and prevent bone-related complications. A holistic approach includes evaluation for secondary etiologies of osteoporosis, medical treatment, and vitamin D and calcium supplementation. Presentation: 6/3/2024

6871 Hungry Bone Syndrome After Parathyroidectomy in End-Stage Kidney Disease: A Case Report Analysis

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

8082 Primary Hyperparathyroidism or Familial Hypocalciuric Hypercalcemia? Why Not Both?

Abstract Disclosure: C.A. Zmijewski: None. P.D. Greenberg: None. S.R. Saul: None. Background: Although considered two separate entities, primary hyperparathyroidism (PHPT) and familial hypocalciuric hypercalcemia (FHH) can present concurrently. Case: A 68-year-old male with hypertension was referred to Endocrinology for hypercalcemia and osteoporosis. The patient reported a long-standing history of intermittent hypercalcemia, first diagnosed at age 30 with a strong family history, both his father and son. He denied symptoms of hypercalcemia, history of nephrolithiasis and fractures, and was not taking calcium supplementations. Labs were notable for intermittent elevations in calcium, the highest being 10.9 mg/dL (8.5-10.5 mg/dL), in addition to phosphorus levels as low as 1.7 mg/dL (2.5-4.5 mg/dL). Vitamin D was replete at 50 ng/mL (32-100 ng/mL) and the highest parathyroid hormone (PTH) was 124 pg/mL (10-66 pg/mL). The 24-hour urine for calcium was 117 mg (100-300 mg) with a Ca/Cr 0.01. DEXA scan showed T scores -2.2 at the right femoral neck and -3.4 at the distal radius (Z score -2.3). Due to the significant osteoporosis, a work-up for secondary causes was completed and was unremarkable. The differential diagnosis for the osteoporosis, elevated parathyroid hormone, and intermittent hypercalcemia included PHPT vs FHH or possibly, a combination. Additional imaging included a renal ultrasound which was negative for nephrolithiasis, Sestamibi and 4D-CT which were both negative for a parathyroid adenoma. Genetic testing confirmed a mutation in the CASR gene. Due to the inability to localize a possible lesion, the decision was made to treat the osteoporosis with zoledronic acid. Conclusion: PHPT is a common endocrine disorder; approximately 100,000 people in the United States develop PHPT annually. Conversely, FHH is a rare endocrine disorder with an incidence rate of 1 in 78,000. PHPT occurs due to the over-secretion of PTH by one or more parathyroid glands. FHH is an inherited autosomal dominant disorder, most commonly due to an inactivating mutation in the calcium-sensing receptor (CASR) gene. Distinguishing PHPT from FHH is important because PHPT is cured with surgery while FHH does not require treatment. Hypercalcemia from FHH, as opposed to PHPT, is suggested by the absence of symptoms, a positive family history, normal or high PTH, and hypocalciuria. However, it can be challenging to separate the two especially in atypical presentations (PTH can be normal in PHPT and elevated in FHH, and Ca/Cr can be &amp;lt; 0.01 in PHPT). But what if these two conditions were to co-exist? Case reports have described patients with concurrent PHPT and FHH (parathyroid adenoma confirmed with pathology and CASR gene mutation confirmed with genetic testing). In these cases, parathyroidectomy can still be considered in co-existing PHPT and FHH to alleviate symptoms and prevent complications of hypercalcemia. Though a rare occurrence, PHPT and FHH have been shown to co-exist in prior case reports. Presentation: 6/1/2024

6928 Vitamin D excess in a patient with hypoparathyroidism after parathyroidectomy

Abstract Disclosure: Z. Zavgorodneva: None. A. Barsegian: None. F. Zhang: None. Introduction. We describe a case of a patient with mild persistent hypoparathyroidism after parathyroidectomy with autotransplantation, which was indicated for ESRD-related secondary hyperparathyroidism. The patient presented with nonspecific complaints and was found to have a high Vitamin D level after long-term moderate-dose Vitamin D supplementation. Case report. A 71-year-old male with a past medical history of end-stage renal disease (ESRD) undergoing hemodialysis for the past 18 years, as well as a history of parathyroidectomy with autoimplantation of parathyroid glands in the forearm in 2010 due to severe secondary hyperparathyroidism, presented to the hospital complaining of generalized weakness and lower extremity cramps that had been ongoing for a few weeks. Further investigations did not reveal evidence of infectious processes. A review of medications indicated the absence of statins among his outpatient medications. No focal neurological deficits or objective signs of muscle weakness were identified. Laboratory findings showed no significant metabolic derangements or haematological abnormalities. Inflammatory markers and creatine phosphokinase were within normal ranges. As part of the workup for generalized subjective weakness and ESRD, Vitamin D levels were checked, revealing a result of of120 ng/mL. The patient reported taking over-the-counter 2000 IU of Vitamin D twice daily for the past six years despite having a normal level of Vitamin D checked five years prior to admission. Calcium supplements were initiated in the postoperative period and continue to be administered at a dose of 600 mg daily. Analysis of the PTH-calcium axis demonstrated persistent mild hypoparathyroidism with hypocalcemia since the time of the surgery. However, there was an observed tendency for calcium levels to improve, especially in the last six years. Vitamin D supplement was discontinued, and the patient was subsequently discharged home with the continuation of physical therapy. Discussion. Explaining the origin of the high level of Vitamin D in this patient poses a challenge. There is limited data in the literature regarding the long-term effects of vitamin D use when the initial Vitamin D levels are normal. Additionally, there are numerous abstracts suggesting significantly higher doses of Vitamin D received for up to 6 years without any evident biochemical or clinical consequences. Moreover, the typical consequences of Vitamin D toxicity, such as hypercalcemia, can not be present in patients who underwent parathyroidectomy. Therefore, it is possible to consider that the severe generalized subjective weakness may be a sign of Vitamin D toxicity itself. Presentation: 6/1/2024