Introduction: Severe hypercalcemia is most commonly caused by primary hyperparathyroidism (PHPT) and malignancy. While standard therapies are effective in most cases, a subset of patients have persistent or refractory hypercalcemia. We present a retrospective case series detailing the clinical characteristics, biochemistry, and outcomes of patients treated with denosumab for hypercalcemia. Cases: Seven patients with severe hypercalcemia were identified, comprising five with PHPT and two with malignancyassociated hypercalcemia. The mean age was 70.4 years (range 55–86), with 71% female (n = 5) and 29% male (n = 2). Baseline corrected calcium ranged from 2.92 to 4.59 mmol/L, with a mean of 3.26 mmol/L. In the PHPT cohort, parathyroid hormone (PTH) levels were significantly elevated (16.7–168 pmol/L), while malignancy patients had suppressed PTH (0.6 and 0.9 pmol/L). Prior to denosumab, 4/7 patients (57%) received bisphosphonates, 3/7 (43%) received calcitonin, and 1/7 (14%) was treated with cinacalcet. Denosumab resulted in a mean reduction in corrected calcium of 0.22 mmol/L from 3.26 to 3.03 mmol/L. Biochemical response was observed in 5/7 patients (71%). Of these, 3 patients (43%) achieved normocalcemia, while 2 patients (29%) demonstrated a partial response. The remaining 2/7 patients (29%) showed no significant improvement in calcium levels. Among responders, the mean time to calcium reduction to <3.0 mmol/L was 27 days (range 7–47). Repeat dosing was required in the majority of patients, with a mean of 1.7 doses per patient (range 1–4), indicating variability in both onset and durability of response. Among patients with PHPT, four underwent parathyroidectomy, and one declined surgery. Both patients with malignancy were managed nonsurgically. Conclusion Denosumab achieved normocalcemia in 43% of patients, with additional partial responses. Its effects were variable, with delayed response and frequent need for repeat dosing, supporting its role as an adjunctive or bridging therapy rather than as a definitive treatment.
Denosumab ; Hypercalcemia ; Retrospective Studies

Introduction: Hypocalcemia in patients with advanced malignancy is usually attributed to bone metastases, vitamin D deficiency, renal impairment, or antiresorptive therapy. Paclitaxel, a taxane-based chemotherapy agent widely used for breast cancer, is not commonly associated with calcium disturbances. Proposed mechanism includes renal tubular dysfunction, renal salt wasting, and disruptions in bone metabolism. In patients with underlying disorders of calcium homeostasis such as hypoparathyroidism, taxanebased chemotherapy such as Docetaxel and Paclitaxel may exacerbate calcium imbalance. We reported a case of recurrent hypocalcemia associated with paclitaxel therapy in a patient with metastatic breast cancer. Case: A 42-year-old female with metastatic breast cancer, involving the liver and bones, had previously undergone neoadjuvant chemotherapy, mastectomy, and adjuvant radiotherapy. Following the disease progression, she was commenced on weekly intravenous paclitaxel at a 20% dose reduction due to prior complications and underlying metabolic risk. She had a history of post-thyroidectomy hypoparathyroidism and had previously been intolerant to docetaxel during the neoadjuvant chemotherapy, which was complicated by hypocalcemia, likely secondary to renal salt wasting. During paclitaxel treatment, she developed recurrent symptomatic hypocalcemia, requiring multiple hospital admissions and repeated intravenous calcium gluconate infusions despite ongoing oral calcium and calcitriol supplementation, which were temporarily increased during the chemotherapy. These episodes occurred intermittently in temporal association with paclitaxel administration, with other causes of hypocalcemia were considered less likely. Conclusion Hypocalcemia associated with paclitaxel is rarely described in literature. This case highlights the importance of monitoring calcium level in patients receiving paclitaxel, particularly in those with pre-existing hypoparathyroidism.
Hypocalcemia ; Hypoparathyroidism ; Breast Diseases ; Paclitaxel

Introduction: Severe hypercalcemia is a life-threatening metabolic emergency that necessitates prompt initiation of systemic therapy due to the risk of cardiac arrhythmias. It is frequently linked to squamous cell carcinoma through the production of parathyroid hormone–related protein, which mediates the development of humoral hypercalcemia of malignancy. Case: This is a case of a 38-year-old male who was diagnosed 1 year ago with locally advanced poorly differentiated basaloid squamous cell carcinoma of the lower anterior mandibular alveolus involving cortical, medullary bone, and perineural invasion. He underwent extensive tumor resection with reconstruction, tracheostomy, and bilateral neck dissection, followed by multiple revision surgeries for postoperative complications. He completed adjuvant chemoradiotherapy. He presented with acute confusion without other systemic symptoms. His Glasgow Coma Scale was E4V4M5. Neurological and systemic examinations were unremarkable, and oral cavity assessment showed no evidence of recurrence. Investigations revealed severe hypercalcemia (5.94 mmol/L) with normal phosphate (1.16 mmol/L) associated with shortened QTc. Other tests were unremarkable, with no evidence of infection, uremia, liver dysfunction, or alternative metabolic causes. Lumbar puncture was unremarkable. His parathyroid hormone level was suppressed at 0.50 pg/ mL. Computed tomography brain showed no evidence of meningoencephalitis, hydrocephalus, cerebral oedema, or metastasis. Aggressive hydration was initiated alongside subcutaneous calcitonin, which was subsequently titrated. However, there was no clinical or biochemical improvement after 1 day, with persistent confusion and calcium remaining at 5.87 mmol/L. Subcutaneous denosumab was then administered, and hemodialysis was initiated on alternate days due to refractory hypercalcemia. This resulted in improvement of calcium levels to 3.2–3.6 mmol/L and resolution of confusion Conclusion Refractory hypercalcemia may represent a late manifestation of advanced squamous cell carcinoma and is an ominous prognostic indicator, necessitating prompt evaluation and oncologic management.
Calcitonin ; Denosumab ; Hypercalcemia ; Renal Dialysis ; Neoplasms

Introduction: Atypical parathyroid adenoma (APA) constitutes approximately 0.5–4.0% of all cases of primary hyperparathyroidism (pHPT). Here, we report a case of APA presenting with severe hypercalcemia, complicated with renal impairment, bilateral medullary nephrocalcinosis, and multiple fragility fractures. Case: A 45-year-old male initially presented with a 6-month history of constipation, polyuria, lethargy, bone pain, and difficulty in initiating micturition. Laboratory investigations revealed impaired renal function with an estimated glomerular filtration rate of 41.4 mL/min, severe hypercalcemia (4.07 mmol/L), and an elevated intact parathyroid hormone (iPTH) level of 104.0 pmol/L (reference range: 1.58–6.03 pmol/L), confirming the diagnosis of pHPT. He was also found to have vitamin D deficiency, with a serum total 25-hydroxyvitamin D level of 46 nmol/L. Ultrasound of the abdomen demonstrated bilateral medullary nephrocalcinosis, while neck ultrasound and Tc-99 m sestamibi parathyroid scintigraphy revealed a concordant lesion in the posterior aspect of the left thyroid lobe, suggestive of a parathyroid adenoma. He returned 3 months later with closed fractures of the right subtrochanteric femur and the right humerus following a fall from standing height. In view of persistent hypercalcemia despite hyperhydration and treatment with zoledronic acid, subcutaneous denosumab (60 mg) was administered, resulting in an improvement in serum calcium levels. A left inferior parathyroidectomy was then performed concurrently with internal fixation of the right femur. The surgery was uneventful. Histopathological examination confirmed an atypical parathyroid adenoma. Postoperatively, the serum calcium and iPTH levels normalized, and the patient remained asymptomatic and normocalcemic during regular follow-up. Conclusion APA remains a diagnostic and therapeutic challenge due to its clinical, biochemical, and histopathological features of equivocal malignancy. Surgical resection remains the mainstay of management of APA, and long-term surveillance is essential in view of its uncertain malignant potential and risk of recurrence.
Hypercalcemia ; Parathyroid Neoplasms

Introduction: X-linked hypophosphatemia (XLH) is a rare genetic disorder caused by PHEX mutations, characterized by chronic hypophosphatemia and renal phosphate wasting, resulting in skeletal, dental, and extra-skeletal complications. To date, no data from Malaysia are currently available on clinical characteristics or health-related quality of life (HRQoL) in paediatric patients. Methodology: This cross-sectional study evaluated HRQoL among children and adolescents with XLH, using validated PROMIS (PatientReported Outcomes Measurement Information System) instruments, sociodemographic and clinical factors associated with HRQoL. This includes children and adolescents with confirmed XLH followed up at Universiti Malaya Medical Centre (UMMC) between November 2024 and March 2025. Results: Seventeen patients were analyzed (76.5% female and 23.5% male). The mean age at symptom onset was 2.82 ± 2.42 years, with a mean age at diagnosis of 5.21 ± 3.29 years. All patients continued to have musculoskeletal complications, including short stature (76.5%), bowing of legs (76.5%), bone/joint pain (47.1%), muscle pain (47.1%), and dental complications (52.9%). Serum alkaline phosphatase improved significantly (p = 0.011); persistent hypophosphatemia and ongoing musculoskeletal manifestations indicated suboptimal disease control. Elevated parathyroid hormone levels and an increase in urine calciumto-creatinine ratio (p = 0.020) lead to secondary hyperparathyroidism and nephrocalcinosis. Adherence to conventional therapy was poor. Non-adherence was associated with worse pain outcomes (higher pain interference [p = 0.037] and greater pain intensity [p = 0.025]). PROMIS scores revealed severely impaired mobility (mean T-score 31.31 ± 12.17), increased fatigue (mean T-score 54.22 ± 7.60), and high pain interference (mean T-score 63.11 ± 9.50). Larger household size was also strongly associated with higher pain intensity (p = 0.004). Conclusion Malaysian children and adolescents with XLH continue to have significantly poor HRQoL, particularly in mobility, fatigue, and pain. These findings highlight the need for access to targeted therapies, such as burosumab, to improve long-term outcomes and QOL in XLH patients.
Adolescent ; Child ; Familial Hypophosphatemic Rickets ; Malaysia ; Quality of Life

OBJECTIVE: To investigate the clinical characteristics and genetic etiology of a primary familial brain calcification (PFBC) family, and analyze the pathogenic mechanism of MYORG gene variants. METHODS: A 17-year-old female who presented to the Second Affiliated Hospital of Zhejiang University School of Medicine on 13 May 2024 with "paroxysmal limb twitching for 1 day" was enrolled. The patient and her parents underwent clinical evaluation and neuroimaging. Peripheral blood samples were collected for whole exome sequencing (WES). Candidate variants were confirmed by Sanger sequencing and interpreted using the American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Interpretation of Sequence Variants (hereinafter referred to as the ACMG Guidelines). This study was approved by Medical Ethics Committee of the Second Affiliated Hospital of Zhejiang University School of Medicine (Ethics No. 2020-674). RESULTS: The patient experienced epileptic seizures. Cranial CT revealed multiple calcifications in the bilateral basal ganglia and cerebellum, with a total calcification score of 23. WES identified compound heterozygous variants in MYORG: c.337_348dup (p.Leu113_Arg116dup), a known pathogenic variant, and c.1268T>G (p.Val423Gly). Segregation analysis showed that the father carried the c.337_348dup heterozygous variant, whereas the mother carried the c.1268T>G heterozygous variant. According to ACMG guidelines, the c.1268T>G variant was classified as "likely pathogenic" (PM2_Supporting + PM3_Supporting + PP1_Supporting + PP3_Moderate + PP4_Supporting). CONCLUSION The novel compound heterozygous MYORG variants c.337_348dup and c.1268T>G have broadened the mutational spectrum of the MYORG gene and further supported compound heterozygosity as an important genetic mechanism in MYORG-related PFBC.
Adolescent ; Female ; Humans ; Brain Diseases/genetics* ; Calcinosis/genetics* ; Exome Sequencing ; GPI-Linked Proteins/genetics* ; Mutation ; Pedigree ; Glycoside Hydrolases

OBJECTIVE: To explore the clinical characteristics and genetic cause of a child with gastrointestinal hemorrhage and Cerebroretinal microangiopathy with calcifications and cysts (CRMCC) and to review the literature. METHODS: Clinical data of a child with gastrointestinal hemorrhage with CRMCC admitted to the Hepatology Department of Hunan Children's Hospital in September 2019 were collected, and peripheral blood DNA of the child and his parents were analyzed by whole exome sequencing. Candidate variants were validated by Sanger sequencing, followed by bioinformatics analysis, American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Interpretation of Sequence Variants pathogenicity classification, and protein structure prediction. A literature search with "Coats Plus syndrome" or "Cerebroretinal microangiopathy with calcifications and cysts" as keywords was conducted at PubMed, China National Knowledge Infrastructure and Wanfang databases to include recently published studies (up to December 2023). This study has been approved by the Ethics Committee of Hunan Children's Hospital (Ethics No. KY2020-07). Informed consent for clinical research was obtained from the guardian of the child. RESULTS: The proband was a 10-year-10-month-old boy. The clinical manifestations were intrauterine and postnatal growth retardation, gastrointestinal hemorrhage, liver fibrosis, panhemopenia, bilateral exudative retinopathy, intracranial lesions and facial pigmentation. WES and Sanger sequencing revealed two novel heterozygous variants in the CTC1 gene: c.787G>A (p.Val263Met) in exon 5 and c.2930C>G (p.Ser977Cys) in exon 17, which were inherited from his mother and father, respectively. According to ACMG pathogenicity classification, both missense variants were classified as variants of uncertain significance (VUS). Protein structure prediction showed the absence of LIG_SH3_3 motif and LIG_SH3_3 motif, and the p.Ser977Cys mutation may affect the binding between CST (CTC1-STN1-TEN) complex and DNA strand. The child had continued to experience recurrent gastrointestinal bleeding episodes despite propranolol treatment, but the condition was controlled after liver transplantation. According to the predefined literature search strategy of this study, a total of 10 relevant articles on pediatric CRMCC patients were retrieved, involving 11 children with gastrointestinal bleeding. Pharmacological and endoscopic therapies play a certain role in the management of CRMCC children complicated with gastrointestinal bleeding. CONCLUSION The CTC1 gene c.787G>A and c.2930C>G variants probably underlay CRMCC in this child. This study has broadened the variation spectrum of CTC1-related diseases and provided a basis for genetic counseling. Liver transplantation may be an important treatment for gastrointestinal hemorrhage in children who do not respond well to medication and endoscopic therapy.
Humans ; Male ; Gastrointestinal Hemorrhage/genetics* ; Child ; Calcinosis/genetics* ; Cysts/genetics* ; Central Nervous System Cysts/genetics* ; Mutation ; Exome Sequencing ; Leukoencephalopathies ; Retinal Diseases ; Seizures ; Muscle Spasticity ; Brain Neoplasms ; Ataxia

INTRODUCTION

Despite advancements in surgical techniques aimed at preserving parathyroid function, postoperative hypocalcemia (PoH) remains a challenge following elective total thyroidectomy. Management typically involves postoperative calcium supplementation; however, some studies suggest preoperative calcium and/or vitamin D supplementation may prevent PoH. This paper analyzed existing studies to determine efficacy of preoperative calcium, with or without vitamin D, in preventing hypocalcemia in total thyroidectomy patients. Level of Evidence: Meta-analysis, Level IV.

METHODS

A systematic review and meta-analysis was conducted with PROSPERO Registration No. CRD42024426410. Searches were performed on PubMED, PubMED Central, Embase, Cochrane Library, and HERDIN without date or language restrictions. Relevant studies underwent multiple screenings, with accepted individual studies assessed for bias or quality. Meta-analysis was performed using SPSS version 24.

RESULTS

A total of 345 studies were initially identified. Following deduplication, exclusion, and quality appraisal, 8 studies were included for analysis. Random effects model was utilized for all analysis due to heterogeneity in data. Results indicate that preoperative calcium, with or without vitamin D supplementation, correlated with higher postoperative calcium levels (z = 3.09, p < 0.001), reduced incidence of laboratory (z= 2.05, p = 0.03) and clinical hypocalcemia (z= 2.94, p < 0.001), and shorter hospital stay (z= 2.32, p = 0.01).

CONCLUSION

Results from the conducted meta-analysis support the proposed practice of providing calcium with or without vitamin D supplementation among patients who are to undergo total thyroidectomy procedures to prevent postoperative hypocalcemia.

Human ; Vitamins ; Vitamin D ; Calcium ; Hypocalcemia ; Thyroidectomy

Primary hyperparathyroidism is characterized by increased secretion of parathyroid hormone, leading to hypercalcemia and skeletal and renal complications. In the past, it was diagnosed when presenting with classical signs and symptoms. Currently, the most common clinical presentation of PHPT is asymptomatic hypercalcemia, often detected by routine screening tests. Due to the changing presentations, the diagnosis can become challenging.

We present BA, a 16-year-old female with a 2-year history of multiple fractures, progressive lytic bone lesions and pain, and kidney stones. She was initially managed as a case of polyostotic fibrous dysplasia. The workup also revealed low levels of vitamin D, hypercalcemia, increased alkaline phosphatase, and elevated intact parathyroid hormones. A neck ultrasound revealed two solid masses posterior to the right thyroid lobe.

She underwent right parathyroidectomy, and a biopsy confirmed a double parathyroid adenoma.

This report also highlights the management of the case in a low-resource setting and the importance of timely diagnosis of primary hyperthyroidism to prevent a delay in the management, which could cause unnecessary pain, bone deformities, and disability.

Human ; Female ; Adolescent: 13-18 Yrs Old ; Parathyroid Hormone ; Parathyroid Neoplasms ; Parathyroidectomy ; Phosphoric Monoester Hydrolases ; Fractures, Multiple ; Hypercalcemia ; Hyperparathyroidism ; Hyperthyroidism

OBJECTIVE: To explore the corrective strategies and effectiveness of osteotomy surgery for severe lower limb deformities in hypophosphatemic rickets. METHODS: A retrospective analysis was conducted on 29 patients with severe lower limb deformities of hypophosphatemic rickets who underwent surgical treatment between February 2012 and August 2024. There were 9 males and 20 females. The age ranged from 13 to 53 years, with an average of 24.6 years. All patients were deformities of both lower limbs, presenting as 24 cases of O-shaped legs, 2 cases of wind-blown deformities, and 3 cases of X-shaped legs. Based on the full-length films of both lower limbs in the standing position before operation, the osteotomy planes of the femur, tibia, and fibula were designed. Among them, if both the same-sided thigh and leg were deformed, staged surgeries of both lower limbs were selected. If only the thigh or leg were deformed, simultaneous surgeries of both lower limbs were selected. The femur deformity was corrected immediately after osteotomy at the deformed plane; the osteotomy fragment was temporarily controlled with an external fixator, which was removed after perform internal fixation with a steel plate. After fibular osteotomy, the Ilizarov frame or Taylor frame was installed on the tibia and fibula. The threaded rods were removed and then tibial osteotomy was performed on the deformed plane. Patients using the Taylor frame did not undergo deformity correction during operation. The external fixators were adjusted starting 7 days after operation to correct the varus, valgus, and rotational deformities of the lower limb. Patients using the Ilizarov frame corrected the rotational deformity of the tibia during operation. The external fixator was adjusted starting 7 days after operation to correct the varus and valgus deformities of the lower limb. During the treatment period, the patient could walk with partial weight-bearing on the operated limb with crutches. The external fixator was removed after the bone healed. Before operation and at last follow-up, the medial proximal tibial angle (MPTA), lateral distal tibial angle (LDTA), posterior proximal tibial angle (PPTA), anterior distal tibial angle (ADTA), anatomic lateral distal femoral angle (aLDFA), posterior distal femoral angle (PDFA), and mechanical axis deviation (MAD), lower limb rotation, limb length discrepancy (LLD) were measured. The self-made scoring criteria were adopted to evaluate the degree of lower limb deformity of the patients. RESULTS: All operations were successfully completed, and no complications such as nerve or vascular injury occurred. The adjustment time of the external fixator of the lower limb after operation was 28-46 days, with an average of 37.4 days. The wearing time of the external fixator ranged from 134 to 398 days, with an average of 181.5 days. Mild pin tract infections occurred in 2 limbs. The osteofascial compartment syndrome occurred in 1 limb after operation. No complications related to orthopedic adjustment of the external fixator occurred in other patients. All patients were followed up 6-56 months, with an average of 28.2 months. At last follow-up, full-length films of both lower limbs in the standing position showed that the coronal mechanical axes of the lower limbs of all patients returned to the normal. At last follow-up, MPTA, LDTA, PPTA, aLDFA, PDFA, MAD, lower limb rotation, LLD, and the score of lower limb deformity significantly improved when compared with those before operation ( P<0.05). There was no significant difference in ADTA between pre- and post-operation ( P>0.05). The degree of lower limb deformity were rated as moderate in 2 cases and poor in 27 cases before operation and as excellent in 7 cases, good in 18 cases, and moderate in 4 cases at last follow-up, with an excellent and good rate of 86.2%. CONCLUSION For severe lower limb deformities in hypophosphatemic rickets, immediate correction of deformities with femoral osteotomy and internal plate fixation, as well as gradually correction of deformities with tibiofibular osteotomy and circular external fixation (Ilizarov frame or Taylor frame), have satisfactory therapeutic effects.
Humans ; Male ; Osteotomy/instrumentation* ; Female ; Adult ; Retrospective Studies ; Tibia/abnormalities* ; Adolescent ; Femur/abnormalities* ; Middle Aged ; Fibula/surgery* ; Rickets, Hypophosphatemic/complications* ; Young Adult ; Treatment Outcome ; External Fixators ; Bone Plates ; Lower Extremity Deformities, Congenital/etiology*