Testing for Primary Hyperparathyroidism in 17,491 Patients With Hypercalcemia

BACKGROUND

Primary hyperparathyroidism (PHPT) is underdiagnosed and associated with many adverse health effects. Historically, many hypercalcemic patients have not received parathyroid hormone (PTH) testing; however, underlying reasons are uncertain. Our goals are to determine the PTH testing rate among hypercalcemic individuals at a large academic health system and to assess for characteristics associated with testing versus not testing for PHPT to inform future strategies for closing testing gaps.

METHODS

This retrospective study included adult patients with ≥1 elevated serum calcium result between 2018 and 2022. Based on the presence or absence of a serum PTH result, individuals were classified as "screened" versus "unscreened" for PHPT. Demographic and clinical characteristics of these groups were compared.

RESULTS

The sample comprised 17,491 patients: 6567 male (37.5%), 10,924 female (62.5%), mean age 59 y. PTH testing was performed in 6096 (34.9%). Characteristics independently associated with the greatest odds of screening were 5+ elevated calcium results (odds ratio [OR] 5.02, P < 0.0001), chronic kidney disease (OR 3.63, P < 0.0001), maximum calcium >12.0 mg/dL (OR 2.48, P < 0.0001), and osteoporosis (OR 2.42, P < 0.0001). Characteristics associated with lowest odds of screening were age <35 y (OR 0.60, P < 0.0001), death during the study period (OR 0.68, P < 0.0001), age ≥85 y (OR 0.70, P = 0.0007), and depression (OR 0.84; P = 0.0081).

CONCLUSIONS

Only 35% of hypercalcemic patients received PTH testing. Although the presence of PHPT-associated morbidity was generally associated with increased rates of screening, hypercalcemic patients with depression were 16% less likely to be tested.

Discrepancies in corrected calcium versus ionised calcium in a geriatric population: an observational study

BACKGROUND

Calcium can be measured as ionised (Ca-ionised) or albumin-adjusted total calcium (Ca-albumin). Current clinical guidelines predominantly utilise Ca-albumin, despite Ca-ionised being the gold standard. Discrepancies can occur between these measurement modalities and can lead to clinical dilemmas. It remains unclear how large these discrepancies are in older patients. This study investigated the discrepancies between Ca-ionised and Ca-albumin in geriatric patients.

METHODS

This is an observational study of all geriatric patients (n = 876) in the Jeroen Bosch Hospital (January 2018 and January 2021) in whom both Ca-ionised and Ca-albumin were measured. Misclassification of calcaemic state (i.e. low, normal or high) was calculated (percentages), the measure of agreement was described using Cohen's Kappa and for the continuous data Pearson's correlation coefficient was used. Relevant categories of age and renal function were considered for effect modification effects and studied by interaction terms in a regression model.

RESULTS

In one-third of the measurements, there was a misclassification. Ca-albumin measurements failed to identify 28% of hypocalcaemia. In 3.5%, hypercalcemia based on Ca-albumin was not confirmed by Ca-ionised. The correlation coefficient between Ca-ionised and Ca-albumin was 0.743 (P = 0.01) and measure of agreement by Kappa was 0.213 (P < 0.001). In the oldest old (≥ 85 years) and patients with eGFR <30 ml/min/1.73 m2 ,the agreement by Kappa was lower, with values of 0.192 and 0.104, respectively.

CONCLUSION

There is a discrepancy between Ca-albumin and Ca-ionised in one-third of the geriatric patients, leading to clinical dilemmas. In the oldest old and patients with renal dysfunction, this problem is most pronounced.

Genetic profile of a large Spanish cohort with hypercalcemia

Introduction

The disorders in the metabolism of calcium can present with manifestations that strongly suggest their diagnosis; however, most of the time, the symptoms with which they are expressed are nonspecific or present only as a laboratory finding, usually hypercalcemia. Because many of these disorders have a genetic etiology, in the present study, we sequenced a selection of 55 genes encoding the principal proteins involved in the regulation of calcium metabolism.

Methods

A cohort of 79 patients with hypercalcemia were analyzed by next-generation sequencing.

Results

The 30% of our cohort presented one pathogenic or likely pathogenic variant in genes associated with hypercalcemia. We confirmed the clinical diagnosis of 17 patients with hypocalciuric hypercalcemia (pathogenic or likely pathogenic variants in the CASR and AP2S1 genes), one patient with neonatal hyperparathyroidism (homozygous pathogenic variant in the CASR gene), and another patient with infantile hypercalcemia (two pathogenic variants in compound heterozygous state in the CYP24A1 gene). However, we also found variants in genes associated with primary hyperparathyroidism (GCM2), renal hypophosphatemia with or without rickets (SLC34A1, SLC34A3, SLC9A3R1, VDR, and CYP27B1), DiGeorge syndrome (TBX1 and NEBL), and hypophosphatasia (ALPL). Our genetic study revealed 11 novel variants.

Conclusions

Our study demonstrates the importance of genetic analysis through massive sequencing to obtain a clinical diagnosis of certainty. The identification of patients with a genetic cause is important for the appropriate treatment and identification of family members at risk of the disease.

[A e-Hypercalcemia]

INTRODUCTION

Hypercalcemia is a common biological abnormality. The etiologies are mainly represented by hyperparathyroidism and neoplastic causes. The other causes, including poisoning, are rare, but should not be neglected.

OBSERVATION

An 82-year-old female patient presented to the emergency room for repeated falls at home, confusion, drowsiness and digestive symptoms. The initial assessment showed hypercalcemia above 3mmol/L. The etiological exploration revealed a very high concentration of 25OH-vitamin D. After repeated interrogations, it appeared that the cause of this intoxication was the intake of a food supplement purchased on the internet, following a prescription from her dentist.

CONCLUSION

Intoxication due to a food supplement containing vitamin D is possible and potentially serious. Raising the awareness of patients and healthcare professionals is necessary in order to prevent this type of poisoning and/or to diagnose it as soon as possible.

Clinical and outcome comparison of genetically positive vs. negative patients in a large cohort of suspected familial hypocalciuric hypercalcemia

OBJECTIVE

Biochemical suspicion of familial hypocalciuric hypercalcemia (FHH) might provide with a negative (FHH-negative) or positive (FHH-positive) genetic result. Understanding the differences between both groups may refine the identification of those with a positive genetic evaluation, aid management decisions and prospective surveillance. We aimed to compare FHH-positive and FHH-negative patients, and to identify predictive variables for FHH-positive cases.

DESIGN

Retrospective, national multi-centre study of patients with suspected FHH and genetic testing of the CASR, AP2S1 and GNA11 genes.

METHODS

Clinical, biochemical, radiological and treatment data were collected. We established a prediction model for the identification of FHH-positive cases by logistic regression analysis and area under the ROC curve (AUROC) was estimated.

RESULTS

We included 66 index cases, of which 30 (45.5%) had a pathogenic variant. FHH-positive cases were younger (p = 0.029), reported more frequently a positive family history (p < 0.001), presented higher magnesium (p < 0.001) and lower parathormone levels (p < 0.001) and were less often treated for hypercalcemia (p = 0.017) in comparison to FHH-negative cases. Magnesium levels showed the highest AUROC (0.825, 95%CI: 0.709-0.941). The multivariate analysis revealed that family history and magnesium levels were independent predictors of a positive genetic result. The predictive model showed an AUROC of 0.909 (95%CI: 0.826-0.991).

CONCLUSIONS

The combination of magnesium and a positive family history offered a good diagnostic accuracy to predict a positive genetic result. Therefore, the inclusion of magnesium measurement in the routine evaluation of patients with suspected FHH might provide insight into the identification of a positive genetic result of any of the CaSR-related genes.

Identification and characterization of a novel CASR mutation causing familial hypocalciuric hypercalcemia

Context

Although a monoallelic mutation in the calcium-sensing receptor (CASR) gene causes familial hypocalciuric hypercalcemia (FHH), the functional characterization of the identified CASR mutation linked to the clinical response to calcimimetics therapy is still limited.

Objective

A 45-year-old male presenting with moderate hypercalcemia, hypocalciuria, and inappropriately high parathyroid hormone (PTH) had a good response to cinacalcet (total serum calcium (Ca2+) from 12.5 to 10.1 mg/dl). We identified the genetic mutation and characterized the functional and pathophysiological mechanisms, and then linked the mutation to calcimimetics treatment in vitro.

Design

Sanger sequencing of the CASR, GNA11, and AP2S1 genes was performed in his family. The simulation model was used to predict the function of the identified mutant. In vitro studies, including immunoblotting, immunofluorescence, a cycloheximide chase study, Calbryte™ 520 Ca2+ detection, and half-maximal effective concentration (EC50), were examined.

Results

This proband was found to carry a de novo heterozygous missense I554N in the cysteine-rich domain of CASR, which was pathogenic based on the different software prediction models and ACGME criteria. The simulation model showed that CASR I554N mutation decreased its binding energy with Ca2+. Human CASR I554N mutation attenuated the stability of CASR protein, reduced the expression of p-ERK 1/2, and blunted the intracellular Ca2+ response to gradient extracellular Ca2+ (eCa2+) concentration. The EC50 study also demonstrated the correctable effect of calcimimetics on the function of the CASR I554N mutation.

Conclusion

This novel CASR I554N mutation causing FHH attenuates CASR stability, its binding affinity with Ca2+, and the response to eCa2+ corrected by therapeutic calcimimetics.

Hypercalcaemia of malignancy: a case of vitamin-D-mediated hypercalcaemia in lymphoma

Hypercalcaemia of malignancy (HCM) is a paraneoplastic syndrome that often portends a poor prognosis. We present an extremely rare (<1%) case of HCM due to extrarenal calcitriol (1,25-(OH)2D) production in a patient with splenic marginal zone lymphoma. A man in his 80s presented with a 3-week history of fatigue, unsteadiness and abdominal pain, and new findings of anaemia, kidney injury and hypercalcaemia. Laboratory evaluation, bone marrow biopsy and positron emission tomography/computed tomography (PET/CT) confirmed the diagnosis of splenic marginal zone lymphoma which produced calcitriol (1,25-(OH)2D3), causing the patient's hypercalcaemia.

[Hypercalcaemia: intensive care or general ward]

Hypercalcaemia is a life-threatening electrolyte imbalance, which not only occurs in the context of an endocrinological disease but is also frequently associated with a tumour. Its severity is determined by the level of deviation from normal, acuity of occurrence, and severity of the symptoms. These are unspecific, can affect any organ system and ultimately result in a life-threatening hypercalcaemic crisis characterised by cardiac arrhythmia, metabolic acidosis, exsiccosis, fever, psychotic states and, ultimately, coma. Endocrinological disorders, drugs such as vitamin D3, vitamin A, checkpoint inhibitors, but also malignancies can be causative for the development of hypercalcaemia. Up to 30% of tumour patients are affected by hypercalcaemia. It is associated with a poor prognosis and a high tumour burden. Malignant hypercalcaemia is mainly caused by PTHrP (parathormone-related peptide), which is secreted by the tumour cells. In oncological patients, serum calcium (ionised calcium and non-ionised calcium) should be evaluated regularly. As the level of serum calcium depends on the albumin concentration, the latter should also be evaluated. Treatment consists of increasing the intravasal volume, increasing calcium excretion and inhibiting calcium reabsorption.

Mucormycosis-induced hypercalcemia: a case report

Hypercalcemia is a vital laboratory marker because it can show underlying severe diseases like cancer and infections. Of all the causes of hypercalcemia, primary hyperparathyroidism, and malignancies are the most common, but granulomatous diseases, such as certain fungal infections, can also be the cause. Here we describe the case of a 29-year-old woman, an insulin-dependent diabetic, found unconscious and tachypneic at home. In the emergency room, the medical team diagnosed diabetic ketoacidosis (DKA) and acute kidney injury (AKI). During hospitalization, despite resolving acidemia, persistent hypercalcemia attracted attention. Laboratory tests showed decreased parathyroid hormone (PTH) levels, confirming non-PTH-dependent hypercalcemia. Computed tomography (CT) of the chest and abdomen demonstrated no alterations, but an upper digestive endoscopy revealed an ulcerated and infiltrative lesion in the stomach. A biopsy showed a granulomatous infiltrate due to mucormycosis infection. The patient received liposomal amphotericin B for 30 days and isavuconazonium for two months. Serum calcium levels improved during treatment. Inquiry of the etiology of hypercalcemia should begin with the PTH assay; high levels are consistent with hyperparathyroidism; low levels, with calcium or vitamin D intoxication, malignancies, prolonged immobilization, and granulomatous diseases. In the latter cases, the overproduction of 1-alpha-hydroxylase by the granulomatous tissue increases the conversion of 25(OH)vitamin D into 1-25(OH)vitamin D, which causes the intestinal absorption of calcium. We have described the first hypercalcemia related to mucormycosis infection in a young diabetic patient, although case presentations associate other fungal infections with elevated serum calcium.

Ionized hypercalcemia can resolve with nutritional modification in cats with idiopathic hypercalcemia or chronic kidney disease

CASE SERIES SUMMARY

Cats with ionized hypercalcemia that were fed diets with either more than 200 mg calcium per 100 kilocalories (kcal), a calcium:phosphorus (Ca:P) ratio greater than 1.4:1 or both, based on diet history, were included in this case series. Ionized hypercalcemia was documented at least twice in all cats before enrollment. Cats were referred for evaluation of ionized hypercalcemia (n = 5) or were incidentally found to have ionized hypercalcemia (n = 5). After medical workups, cats were diagnosed with either idiopathic hypercalcemia (IHC; n = 7) or chronic kidney disease (n = 3). Cats receiving medications to treat IHC (eg, alendronate, corticosteroids) were excluded. Nutritional recommendations were made to transition the cats to diets with less thn 200 mg calcium per 100 kcal and a Ca:P ratio less than 1.4:1. Ionized calcium (iCa) concentrations were rechecked in all cats, with a median recheck time of 9 weeks (range 3-20). Of the 10 cats, nine (90%) had a decrease in iCa. Of the 10 cats, six (60%) became normocalcemic after the diet change, three (30%) had a partial response and one (10%) did not respond. Of the four cats that did not achieve normocalcemia with a change in diet, two (50%) received chia seeds (1-2 g per day), and at the next recheck, both cats' iCa concentrations had normalized. Three cats had a long-term follow-up. Ionized normocalcemia was maintained for at least two consecutive follow-up visits over a median follow-up period of 33 weeks (range 12-34).

RELEVANCE AND NOVEL INFORMATION

Dietary calcium concentrations and the dietary Ca:P ratio appear to be important variables in considering nutritional approaches for hypercalcemic cats.

Measurement of plasma total calcium before plasma free ionized calcium - a possibility with affordable pitfalls

Free ionized calcium (fCa) is considered the gold standard for assessing calcium status in patients, but it is relatively expensive and is associated with several preanalytical and analytical error sources. We investigated the feasibility of using a reflex test that involves first measuring total calcium (tCa) and if out of reference range, then measure fCa, with expectation of reducing the number of fCa measurements. We used data from 1815 unique patients with concurrent measurement of fCa, tCa and albumin adjusted calcium (aCa). Patients were stratified by albumin level, and the association of fCa to tCa and aCa respectively was assessed with linear regression. The regression analysis showed the best linearity for tCa and aCa at albumin <35 g/L (R2: 0.80-0.90), and the poorest at albumin >40 g/L (R2: tCa 0.58; aCa 0.59). We examined the accuracy of hypo- and hypercalcemia classifications for tCa, aCa and the reflex test. aCa had more misclassifications of hypo- and hypercalcemia than tCa, with respectively 25% and 21%. Implementation of the reflex test would correct any false hypo- or hypercalcemia classified by tCa, leaving only false negative results corresponding to 9% of all tCa measurements. False negative results were on average 0.04 mmol/L above or below the reference range of fCa. Implementation of the reflex test reduces the number of fCa by 68% without major errors diagnosing hyper- or hypocalcemia.

Vitamin D Abuse in Pursuit of "Gains" Resulting in Acute Kidney Injury

Vitamin toxicity represents an increasingly frequent clinical diagnosis and can be difficult to initially recognize given the plethora of over-the-counter supplements available. The young, active, and heavily male population of the military is especially susceptible to such supplementation pitfalls. Here we present the case of acute renal failure with hypercalcemia that was found to be secondary to unrecognized high-dose over-the-counter vitamin supplementation and subsequent vitamin D hypervitaminosis initiated by the patient in the hope of boosting testosterone production. This clinical scenario demonstrates the dangers of easily accessible, often seemingly benign supplements and the need for greater education and awareness of supplementation use.

Lithium-associated primary hyperparathyroidism:: An evaluation of screening and referral patterns in a southeastern veteran population

BACKGROUND

Long-term lithium therapy has a well-established but under-recognized association with primary hyperparathyroidism. Rates of hypercalcemia, screening for primary hyperparathyroidism, and referral for parathyroidectomy were evaluated among United States veterans on long-term lithium therapy.

METHODS

Patients undergoing chronic long-term lithium therapy (>12 months) were identified from 1999 to 2022. Demographics, long-term lithium therapy duration, post-treatment calcium, parathyroid hormone, creatinine, and vitamin D levels were abstracted. Rates of screening for hypercalcemia (calcium ≥10.2 mg/dL), primary hyperparathyroidism (parathyroid hormone ≥30 pg/mL in the setting of hypercalcemia), referral for parathyroidectomy, and outcomes were evaluated.

RESULTS

A total of 1,356 patients underwent long-term lithium therapy, 514 of whom received chronic long-term lithium therapy. Baseline characteristics of patients with and without post-treatment hypercalcemia were compared. Of 148 patients with post-treatment hypercalcemia, 112 (74.7%) underwent no further evaluation for primary hyperparathyroidism, while 36 (25.3%) patients had a parathyroid hormone level recorded. Although 33 (91.7%) hypercalcemic patients screened positive for primary hyperparathyroidism, only 5 (13%) were referred for parathyroidectomy. Of the 4 patients who underwent parathyroidectomy, mean calcium was 11.2 mg/dL (range 11.1-11.4), and mean parathyroid hormone was 272 pg/mL (range 108-622). Three patients were localized on preoperative imaging, 2 of whom underwent unilateral exploration with cure, with 1 experiencing recurrence at 31 months. The remaining patient who localized preoperatively underwent bilateral exploration and had 2 ipsilateral glands resected and persistence. The patient who did not localize preoperatively underwent bilateral exploration with 3 gland resection and cure.

CONCLUSIONS

Screening for primary hyperparathyroidism and referral for parathyroidectomy are underutilized in United States veterans undergoing chronic long-term lithium therapy. Institutional protocols to standardize screening, surveillance, and referrals to endocrinology/endocrine surgery could benefit this population at increased risk for primary hyperparathyroidism.

Primary hyperparathyroidism

Primary hyperparathyroidism (PHPT), the most common cause of hypercalcemia, is most often identified in postmenopausal women with hypercalcemia and parathyroid hormone (PTH) levels that are either frankly elevated or inappropriately normal. The clinical presentation of PHPT includes three phenotypes: target organ involvement of the renal and skeletal systems; mild asymptomatic hypercalcemia; and more recently, high PTH levels in the context of persistently normal albumin-corrected and ionized serum calcium values. The factors that determine which of these three clinical presentations is more likely to predominate in a given country include the extent to which biochemical screening is employed, the prevalence of vitamin D deficiency, and whether a medical center or practitioner tends to routinely measure PTH levels in the evaluation of low bone density or frank osteoporosis. When biochemical screening is common, asymptomatic primary hyperparathyroidism is the most likely form of the disease. In countries where vitamin D deficiency is prevalent and biochemical screening is not a feature of the health care system, symptomatic disease with skeletal abnormalities is likely to predominate. Finally, when PTH levels are part of the evaluation for low bone mass, the normocalcemic variant is seen. Guidelines for surgical removal of hyperfunctioning parathyroid tissue apply to all three clinical forms of the disease. If guidelines for surgery are not met, parathyroidectomy can also be an appropriate option if there are no medical contraindications to surgery. In settings where either the serum calcium or bone mineral density is of concern, and surgery is not an option, pharmacological approaches are available and effective. Referencing in this article the most current published articles, we review the different presentations of PHPT, with particular emphasis on recent advances in our understanding of target organ involvement and management.

Pneumocystis jirovecii pneumonia presenting with severe, refractory hypercalcaemia in an immunosuppressed renal transplant patient: Review of the literature and novel biochemical insights

Pneumocystis jirovecii pneumonia (PJP) is a rare but serious complication of immunosuppression post-solid organ transplantation. We present a case of refractory, severe hypercalcaemia due to PJP in a renal transplant recipient. Treatment of PJP led to normalisation of the patient's calcium levels, and clinical improvement. To further explore the proposed calcitriol-driven mechanism leading to hypercalcaemia in PJP, we performed biochemical analysis on pre- and post-treatment serum and bronchoalveolar lavage sample at the time of PJP diagnosis. We confirmed high circulating and pulmonary levels of calcitriol in acute, untreated PJP with severe hypercalcaemia. PJP treatment led to reduction of circulating calcitriol to within normal range. We present this case, together with a literature review of similar reported cases, and the novel biochemical evidence supporting extra-renal production of calcitriol by activated pulmonary macrophages as the mechanism underpinning hypercalcaemia in PJP.

IgG4-related disease presenting as severely symptomatic hypercalcemia: A case report and review of literature

Immunoglobulin G4-related disease (IgG4-RD)-associated hypercalcemia has rarely been reported. We report a case of IgG4-RD that presented as severe symptomatic hypercalcemia. A 50-year-old woman with a history of sustained bilateral periorbital swelling and proptosis for more than 5 years presented to our hospital complaining of a 3-day history of significant and progressive nausea, vomiting, loss of appetite, fatigue, and pruritus. She denied a long history of medication. On admission, laboratory tests showed severe hypercalcemia with serum adjusted calcium elevated to 4.34 mmol/L and renal dysfunction with serum creatinine elevated to 206 μmol/L. Urinary calcium excretion was increased. The serum IgG4 subclass was markedly elevated to 22.4 g/L with polyclonal hypergammaglobulinemia. Tests of autoantibodies were all negative. Bone metabolism markers that reflect the activity of osteoblasts and osteoclasts were all significantly elevated. However, the levels of intact parathyroid hormone and 25(OH) vitamin D3 were decreased. B-ultrasonography showed chronic inflammation of bilateral submandibular glands. Neither bone marrow biopsy nor positron emission tomography - computed tomography examination showed evidence of neoplastic diseases. The patient was treated with intravenous saline infusion, loop diuretics, salmon calcitonin, glucocorticoids, and hemodialysis with a good response.

[New Mutation of CYP24A1 in a Case of Idiopathic Infantile Hypercalcemia Diagnosed in Adulthood]

Mutations in the 24-hydroxylase gene CYP24A1 have been recognized as causes of childhood idiopathic hypercalcemia (IIH), a rare disease (incidence <1:1,000,000 live births) characterized by increased vitamin D sensitivity, with symptomatic severe hypercalcemia. IIH was first described in Great Britain two years after the start of a program of vitamin D supplementation in milk for the prevention of rickets, manifesting in about 200 children with severe hypercalcemia, dehydration, growth failure, weight loss, muscle hypotonia, and nephrocalcinosis. The association between the epidemic occurrence of IIH and vitamin D administration was quickly attributed to intrinsic hypersensitivity to vitamin D, and the pathogenic mechanism was recognized in the inactivation of Cytochrome P450 family 24 subfamily A member 1 (CYP24A1), which was identified as the molecular basis of the pathology. The phenotypic spectrum of CYP24A1 mutation can be variable, manifesting predominantly with childhood onset and severe symptomatology (severe hypercalcemia, growth retardation, lethargy, muscle hypotonia, dehydration), but also with juvenile-adult onset forms with nephrolithiasis, nephrocalcinosis, and alterations in phosphocalcium homeostasis. We describe the case of a patient in whom the diagnosis of IIH was made in adulthood, presenting with finding of nephrocalcinosis in childhood, and with subsequent onset of severe hypercalcemia with hypercalciuria, hypoparathyroidism, hypervitaminosis D, and recurrent renal lithiasis. Genetic investigation revealed the presence in homozygosity of the c_428_430delAAG_p.Glu143del variant in the CYP24A1 gene with autosomal recessive transmission, a mutation not reported in the literature.

Treatment of hypokalemia with amiloride unmasked hypercalcemia and hyperparathyroidism: A case report

Colonic pseudo-obstruction, also called Ogilvie's syndrome, occurs due to impaired intestinal propulsion, and may be caused by electrolyte imbalances such as hypokalemia and some endocrine disorders such as hyperparathyroidism. Secretory diarrhea due to intestinal pseudo-obstruction can cause hypokalemia. Diuretics such as amiloride can be used to treat hypokalemia, however in this case, treatment with amiloride induced hypercalcemia and unmasked hyperparathyroidism. A 73-year-old female with a history of hypertension and parathyroid adenoma presented with recurrent colonic pseudo-obstruction and chronic hypokalemia. Her hypokalemia was treated with amiloride, causing hypercalcemia of 14.4 mg/dL, elevated PTH, and altered mental status. Amiloride was subsequently discontinued with improvement in her symptoms, and her hyperparathyroidism was treated with cinacalcet. To our knowledge, this is the first report of amiloride unmasking hyperparathyroidism and inducing hypercalcemia.

Clinical heterogeneity and therapeutic options for idiopathic infantile hypercalcemia caused by CYP24A1 pathogenic variant

OBJECTIVES

Infantile hypercalcemia-1 (HCINF1) is a rare disease caused by pathogenic variants in the CYP24A1 gene, resulting in the inability to metabolize active vitamin D. This leads to hypercalcemia and severe complications.

CONTENT

On December 8th, 2022, a systematic literature search was conducted in PubMed, Wanfang, and CNKI using the keywords "hypercalcemia" and "CYP24A1". Data extraction included patient demographics, clinical presentation, treatment medications, and outcomes. The findings were synthesized to identify common patterns and variations among cases and to assess the efficacy of different therapies in reducing serum calcium. Our findings revealed two distinct peaks in the incidence of HCINF1 caused by CYP24A1 pathogenic variant. Kidney stones or renal calcifications were the most common clinical manifestations of the disease, followed by polyuria and developmental delay. Laboratory investigations showed hypercalcemia, elevated vitamin D levels, hypercalciuria, and low parathyroid hormone. Genetic analysis remains the only reliable diagnostic tool. Although there is no definitive cure for HCINF1, multiple drugs, including bisphosphonates, calcitonin, and rifampicin, have been used to control its symptoms. Blocking the production and intake of vitamin D is the preferred treatment option.

SUMMARY AND OUTLOOK

Our review highlights the basic clinical and biochemical features of HCINF1 and suggests that targeted diagnostic and therapeutic strategies are needed to address the clinical heterogeneity of the disease. The insights gained from this study may facilitate the development of innovative treatments for HCINF1.

Persistent hypercalcemia mimicking hypophosphatasia after discontinuation of a ketogenic diet: a case report

OBJECTIVES

Hypercalcemia has been reported as an uncommon complication of the ketogenic diet (KD). Here we present a toddler whose hypercalcemia persisted for 2 months after stopping the KD.

CASE PRESENTATION

A 2 year 11-month-old child with global developmental delay, infantile spasms, neuromuscular weakness with limited mobility, tracheostomy and ventilator dependence, and oropharyngeal dysphagia with G-tube dependence presented with hypercalcemia in the setting of recurrent vomiting. At presentation, the patient was adherent to a KD and taking topiramate since infancy for intractable seizures. His laboratory parameters at presentation showed hypercalcemia (11.9 mg/dL), hypercalciuria, acute renal failure, low alkaline phosphatase (76 IU/L [110-302 IU/L]), parathyroid hormone (PTH) <6 pg/mL (18-80 pg/mL), normal thyroid function, cortisol and vitamin D level. The patient's hypercalcemia persisted post-discontinuation of the KD and topiramate. PTH-related protein was mildly elevated at 15.3 pmol/L. Follow-up laboratory and imaging studies ruled out malignancy. He was managed with calcitonin 4 u/kg/dose Q12H × 1 day and 8 u/kg/dose Q8H × 1 day, hydration and low-calcium formula. Post-discontinuation of the KD, normalization of alkaline phosphatase levels preceded the normalization of calcium on day 55 and PTH on day 85.

CONCLUSIONS

Hypercalcemia may persist for an extended period after weaning from a KD; lab parameters may mimic that of hypophosphatasia as previously described in the literature. Normalization of alkaline phosphatase, a marker of bone turnover, indicates recovery from the adynamic state induced by the KD and typically precedes the normalization of calcium and PTH.

[Diagnosis and management of primary hyperparathyroidism during pregnancy: A systematic review and a longitudinal case study]

OBJECTIVE

There is no specific recommendation for management in pregnant women: the aim of this review, based on a clinical case study, is to clarify its development, complications, risk factor and treatment.

METHODS

A review of the literature was performed by consulting the Pubmed, Cochrane Library, and Science Direct databases.

RESULTS

Primary hyperparathyroidism is defined as excessive production of parathyroid hormone resulting in hypercalcemia. The prevalence of primary hyperparathyroidism during pregnancy is not known. Indeed, the symptomatology, related to hypercalcemia, is not very specific and easily confused with the clinical manifestations of pregnancy. The physiological changes specific to the pregnant state frequently lead to a slight hypocalcemia which may complicate the diagnosis of primary hyperparathyroidism. Primary hyperparathyroidism results from a parathyroid adenoma in the majority of cases and is detected by ultrasound during pregnancy. Primary hyperparathyroidism in pregnancy causes significant risks to both mother and fetus. The maternal complication rate is 14-67%, however, the most serious complication is hypercalcemic crisis, which requires increased surveillance in the postpartum period. Obstetrical complications are also induced by primary hyperparathyroidism, such as acute polyhydramnios, or intrauterine growth retardation. The fetal complication rate can reach 45-80% of cases with neonatal hypocalcemia as the main complication. If medical treatment is based on hyperhydration, only surgical treatment is curative.

CONCLUSION

Surgery should be proposed to symptomatic patients or those with high blood calcium levels, discussed in interdisciplinary committee and should be organized ideally in the second trimester to avoid maternal and fetal complications.

Case Report: Multiple prolactinomas in a young man with Kallmann syndrome and familial hypocalciuric hypercalcemia

Introduction

The occurrence of prolactinomas in sex hormone treated patients with central hypogonadism is extremely rare.

Case presentation

We present a Caucasian male patient who was diagnosed with Kallmann syndrome (KS) at age 15 years. Testosterone treatment was started. At age 26 the patient presented with mild headache. MRI revealed two separate pituitary adenomas along with the absence of the olfactory bulbs. Given the presence of marked hyperprolactinemia (17x upper limit of the reference range) the diagnosis prolactinoma was made and treatment with cabergoline was started which resulted in a complete biochemical response and in marked reduction of both adenomas in size. Hypogonadism persisted and testosterone replacement therapy was continued. Genetic testing of genes associated with pituitary tumors, Kallmann syndrome and idiopathic hypogonadotropic hypogonadism was negative. Mild concomitant hypercalcemia in accordance with familial hypocalciuric hypercalcemia (FHH) prompted mutation analysis of the calcium receptor (CASR) gene which yielded a pathogenic inactivating variant.

Discussion/conclusion

The presence of two separate prolactinomas in a patient with KS has not yet been reported in the literature. The effect of sex hormone treatment of KS patients on the possible development of prolactinoma is unknown at present. The occurance of multiple prolactinomas in our patient suggests increased susceptibility. Although CaSR is expressed in GnRH neurons in mouse brain and CaSR deficient mice have a reduced hypothalamic GnRH neuronal population, the relevance of the CASR gene variant in our patient for the KS phenotype is unclear at present.

Isolated muscular sarcoidosis presenting as hypercalcaemic renal failure

The case report describes the details of a man in his 40s admitted for evaluation of renal failure. Biochemical testing revealed parathyroid hormone (PTH) -independent hypercalcaemia. The evaluations for the usual causes such as malignancies, granulomatous diseases, multiple myeloma and vitamin D toxicity were negative. Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) scan identified diffuse uptake in the muscles, and the subsequent muscle biopsy showed non-caseating granulomas suggestive of granulomatous myositis, possibly sarcoidosis, in view of raised ACE levels and the absence of other causes. The patient showed a dramatic response to glucocorticoids, with prompt relief of symptoms and normalisation of serum calcium and creatinine. The case highlights the importance of considering sarcoid myositis in the evaluation of hypercalcaemia and the need for prompt initiation of glucocorticoid therapy to achieve favourable outcomes. The successful use of FDG-PET in diagnosing PTH-independent hypercalcaemia suggests its potential as a valuable tool in the diagnostic algorithm for this condition.

Renal sarcoidosis presenting with chronic kidney disease and hypercalcemia

Sarcoidosis is a multisystem inflammatory disease that most frequently affects the lungs, lymph nodes, eyes, and skin. Renal involvement is clinically rare. We describe a 72-year-old male who presented with chronic kidney disease and elevated serum calcium and angiotensin-converting enzyme. Renal biopsy pathology showed chronic granulomatous interstitial nephritis. Renal function was significantly improved after glucocorticoid therapy. This case emphasizes that chronic kidney disease and hypercalcemia can be clues for renal sarcoidosis. Early renal biopsy and projective treatment is beneficial for renal outcome.

[Milk-alkali syndrome: a careful history is crucial in diagnosing hypercalcemia]

BACKGROUND

Milk-alkali syndrome is a rare cause of hypercalcemia in the Netherlands, due to ingestion of large amounts of calcium and absorbable alkali.

CASE DESCRIPTION

A 38-year-old female patient was admitted with severe stomach pain, vomiting and weight loss. Laboratory results showed hypercalcemia and acute kidney injury. We initially suspected that the hypercalcemia was related to primary hyperparathyroidism, a malignancy with bone metastasis or a granulomatous disease. Gastroduodenoscopy, however, revealed a duodenal ulcer, which turned out to be Helicobacter pylori-related. A thorough history revealed that the patient had consumed large amounts of milk and antacids to relieve symptoms of heartburn. In light of this history, milk-alkali syndrome was diagnosed.

CONCLUSION

The case aims to underline the importance of a thorough history in patients with hypercalcemia. The use of over-the-counter medications and dairy products should be evaluated in all patients presenting with hypercalcemia.

Successful Hemodialysis Treatment of Severe Hypercalcemia Following COVID-19 in Multiple Myeloma: A Case Report

BACKGROUND Hypercalcemia, a serum calcium exceeding 10.5 mg/dL, is a multi-factorial metabolic disorder that results from an imbalance in calcium homeostasis. CASE REPORT We report a case of a 67-year-old male with recently diagnosed multiple myeloma who presented to our emergency department 3 weeks after COVID-19 infection with altered mental status and a fall. On admission he was found to have severe hypercalcemia with a level over 18.0 mg/dL. Despite IV fluids, calcitonin, steroids, and zoledronic acid, he had persistent, critically elevated calcium levels. The decision to initiate hemodialysis was made, which successfully treated his hypercalcemia. CONCLUSIONS This report presents a case of malignant hypercalcemia in an individual with COVID-19 and multiple myeloma and highlights the importance of considering dialysis as a viable treatment for hypercalcemia when other modalities have failed.

A case report of Williams syndrome with main clinical manifestation of hypercalcemia and gastrointestinal bleeding as the main clinical manifestations, and with an accompanying literature review

BACKGROUND

Williams syndrome is an autosomal dominant multisystem disorder caused by a 1.5-1.8 Mb deletion on chromosome 7q11.23. It is characterized by facial deformations, cardiovascular abnormalities, developmental delays, gastrointestinal manifestations, and endocrine disorders.

CASE DESCRIPTION

A 1-year-old child presenting with developmental delays, special facial features, gastrointestinal bleeding, renal calcium deposition, and hypotonia was admitted to the hospital for "hypercalcemia and gastrointestinal bleeding." Genetic testing showed a deletion mutation in the 7q11.23 region. Currently, the child receiving treatment to promote calcium excretion and rehabilitation training, but hypercalcemia has recurred.

CONCLUSION

The clinical phenotype of Williams syndrome is complex, and different severities, characterized by developmental delays, facial deformities, cardiovascular abnormalities, gastrointestinal symptoms and endocrine disorders, should be considered in children. The syndrome may require thorough genetic testing for diagnosis and early intervention treatment to improve patient quality of life.

Case Report: Hypercalcemia as a manifestation of acute adrenal crisis precipitated by fluconazole use, and a review of the literature

Acute adrenal crisis classically presents with vomiting, altered sensorium, and hypotension. We describe a unique case manifesting with severe hypercalcemia. Addisonian crisis was unusually precipitated by fluconazole use. We reviewed other reported cases and discuss the possible mechanisms of hypercalcemia in adrenal insufficiency. This 67-year-old man presented with fever, cough, and vomiting for 1 week and with anorexia and confusion for 3 weeks. He was hypotensive and clinically dehydrated. Investigations revealed left-sided lung consolidation, acute renal failure, and severe non-parathyroid hormone (PTH)-mediated hypercalcemia (calcium, 3.55mol/L; PTH, 0.81pmol/L). Initial impression was pneumonia complicated by septic shock and hypercalcemia secondary to possible malignancy. He received mechanical ventilation; treatment with intravenous fluids, inotropes, and hydrocortisone for septic shock; and continuous renal replacement therapy with low-calcium dialysate. Although hypercalcemia resolved and he was weaned off inotropes, dialysis, and hydrocortisone, his confusion persisted. When hypercalcemia recurred on day 19 of admission, early morning cortisol was <8 nmol/L, with low ACTH level (3.2 ng/L). Other pituitary hormones were normal. Hypercalcemia resolved 3 days after reinstating stress doses of hydrocortisone, and his mentation normalized. On further questioning, he recently received fluconazole for a forearm abscess. He previously consumed traditional medications but stopped several years ago, which may have contained glucocorticoids. He was discharged on oral hydrocortisone. Cortisol levels improved gradually, and glucocorticoid replacement was ceased after 8 years, without any recurrence of hypercalcemia or Addisonian crisis. Both hypercalcemia and adrenal insufficiency may present with similar non-specific symptoms. It is important to consider adrenal insufficiency in hypercalcemia of unclear etiology.

[Hypercalcium crisis and postoperative hungry bone syndrome caused by primary hyperparathyroidism: a case report]

To review the diagnosis and treatment of a case of hypercalcium crisis caused by primary hyperparathyroidism（PHPT） and prophylactic treatment of hungry bone syndrome. In a 32-year-old male with hypercalcemia, the main manifestations were loss of appetite, nausea, polyuria, polydipsia, fatigue, lethargy, etc. parathyroid hormone, serum calcium increased, thyroid function was normal, thyroid color ultrasound and MRI showed space-occupying behind the right thyroid, radionuclide examination showed abnormal imaging agent concentration in the right parathyroid area, there was a history of pathological fracture. Clinically diagnosed as hypercalcemia crisis secondary to PHPT.

The Diagnosis of Gastric Cancer due to a Parathyroid Adenoma Almost Missed in a Hypercalcemia Patient with Severe Vomiting

BACKGROUND

Hypercalcemia is a relatively common clinical problem. However, the differential diagnosis between hypercalcemia combined with hyperparathyroidism and a malignant tumor is difficult.

METHODS

Appropriate laboratory tests, ultrasound and static imaging of the parathyroid, electronic gastroscopy, and histological examinations were used.

RESULTS

The patient was found to have primary hyperparathyroidism due to hypercalcemia, with a parathyroid adenoma visible on color Doppler ultrasound and PET. The hypercalcemia was corrected after surgical resection. As the symptoms of nausea and vomiting did not improve, further investigations were undertaken, and gastric cancer was found on gastroscopy.

CONCLUSIONS

Both primary hyperparathyroidism and gastric tumors may present with symptoms of nausea and vomiting. Clinically, multiple disease possibilities should be considered to explain a particular symptom.

PURTSCHER-LIKE RETINOPATHY IN A PATIENT WITH MILK-ALKALI SYNDROME AND PANCREATITIS

PURPOSE

To report a case of Purtscher-like retinopathy in a patient with milk-alkali syndrome and pancreatitis.

METHODS

Case report and review of the literature.

RESULTS

A 46-year-old woman presented with decreased vision following discharge from the intensive care unit, where she had been admitted for milk-alkali syndrome secondary to long-term calcium supplementation and over-the-counter antacid use, and pancreatitis. Dilated examination showed ischemic retinal whitening and retinal hemorrhages in the posterior pole bilaterally consistent with Purtscher-like retinopathy. Over three months, the retinopathy resolved and her vision improved.

CONCLUSION

Milk-alkali syndrome is the clinical triad of hypercalcemia, renal failure, and metabolic alkalosis and occurs secondary to the consumption of large amounts of calcium and alkali. The hypercalcemia associated with milk-alkali syndrome may cause pancreatitis, which can lead to Purtscher-like retinopathy.

Eclampsia as the First Manifestation of Primary Hyperparathyroidism: a Case Report

BACKGROUND

This study aimed to explore the diagnosis and treatment strategies of eclampsia during pregnancy and postpartum acute pancreatitis caused by primary hyperparathyroidism.

METHODS

This study reported a 26-year-old patient who had maternal eclampsia as her first symptom and was admitted to the hospital. The pregnancy was terminated by cesarean section immediately. Postpartum life-threatening complications, such as severe hypercalcemia and acute pancreatitis, occurred afterward. Following completion of the relevant examination, primary hyperparathyroidism was initially considered to be the cause. Symptomatic treatment is ongoing and will be improved, and the patient will be admitted again for parathyroidectomy.

RESULTS

The patient gave birth to a premature neonate via cesarean section. The postpartum diagnosis was primary hyperparathyroidism, for which post-surgical pathology showed a parathyroid adenoma.

CONCLUSIONS

The clinical manifestations of pregnancy with primary hyperparathyroidism are atypical but may cause serious maternal and fetal complications. Early diagnosis and appropriate treatment can prevent serious prenatal and postnatal complications and foster better pregnancy outcomes.

Hypercalcemic crisis as a presentation of primary hyperparathyroidism

Hyperparathyroidism-induced hypercalcemic crisis (HIHC) is an unusual state of marked progressive primary hyperparathyroidism (PHPT). Patients have severe hypercalcemia and may have severe symptoms such as kidney failure, acute pancreatitis, and mental changes. PHPT is due to the presence of a single gland adenoma/ disease in 80 to 85%; parathyroid carcinoma is reported in <1%. Among patients with adenoma, atypical parathyroid tumor can be found infrequently. Parathyroidectomy is the only curative approach for PHPT. In this report we present three cases of HIHC due to giant parathyroid adenomas (GPAs), one of them with histopathological characteristics of an atypical parathyroid tumor, with satisfactory evolution after parathyroidectomy.

Cancer-related hypercalcemia and potential treatments

Cancer-related hypercalcemia is a common finding typically seen in patients with advanced cancer and occurs in about 20 to 30 percent of cases. The most common cause of hypercalcemia in hospitalized patients is hypercalcemia due to malignancy.This clinical problem is seen in patients with both solid tumors and patients with hematologic malignancies. Hypercalcemia is associated with a poor prognosis in oncology patients. This pathologic condition can occur due to many different mechanisms but is usually caused by abnormal calcium use resulting from bone resorption, intestinal absorption, or renal excretion. Hypercalcemia may present with a wide range of symptoms ranging from gastrointestinal system symptoms to neurologic symptoms. Timely diagnosis and initiation of treatment by the physician significantly reduce the risk of complications. Treatment aims to decrease serum calcium by increasing calciuresis, decreasing bone resorption, and decreasing intestinal calcium absorption. The mainstays of treatment are IV hydration, bisphosphonates and calcitonin, denosumab, and in some patients, prednisone, and cinacalcet. Patients with underlying advanced kidney disease and refractory severe hypercalcemia should be evaluated for hemodialysis. Every physician dealing with oncology patients should know the fastest and most effective management of hypercalcemia. We aimed to contribute in this sense.

Multiple myeloma with unexplained isolated anaemia in a 24year old man- a case report

Background: Multiple myeloma (MM) is a disease of the elderly with a median age at presentation of 70 years. It is rare to diagnose MM in individuals less than 40 years and even extremely rare in those less than 30 years of age. MM is usually suspected in those aged 50 years and above having a combination of hypercalcemia, renal insufficiency, anaemia and bone lesions. Although anaemia is a common clinical feature of MM, it is very rare that anaemia would be the only clinical presentation, hence the need to report this index case. Case Presentation: We present a rare case of MM in a 24-year- old male who presented with only symptomatic anaemia.Investigations for the cause of anaemia, including Bone marrow aspiration cytology revealed a diagnosis of MM ISS stage II.Here, we highlighted the need to seek early haematologist consultation in investigating patients’ whose cause of anaemia is notimmediately obvious from the clinical presentation and routine laboratory investigations. Conclusion: MM can present at a younger age with unexplained anaemia without bone pains or renal insufficiency. High level of suspicion for MM is required in young patients with unexplained anaemia Keywords: Multiple myeloma; isolated anaemia; young patient.

Familial hypocalciuric hypercalcaemia type 1 caused by a novel heterozygous missense variant in the CaSR gene, p(His41Arg): two case reports

BACKGROUND

Familial hypocalciuric hypercalcaemia (FHH) is a rare, inherited disorder of extracellular calcium sensing. It is clinically characterised by mild to moderate parathyroid hormone dependent hypercalcaemia, an autosomal dominant pattern of inheritance, and a normal to reduced urinary calcium excretion in spite of high serum calcium.

CASE PRESENTATION

We report two cases of FHH in a family caused by a novel pathogenic missense variant in the CaSR gene, p. His41Arg. Case 1, describes a 17 year old female with no significant past medical history, admitted with acute appendicitis requiring laparoscopic appendectomy and reporting a six month history of polydipsia. Routine investigations were significant for hypercalcaemia, corrected calcium 3.19 mmol/L (2.21-2.52mmol/L), elevated parathyroid hormone of 84pg/ml (15-65pg/ml) and a low 24-hour urine calcium of 0.75mmol/24 (2.50-7.50mmol/24). She was initially managed with intravenous fluids and Zolendronic acid with temporary normalisation of calcium though ultimately required commencement of Cinacalcet 30 mg daily for persistent symptomatic hypercalcaemia. Genetic analysis was subsequently positive for the above variant. Case 2, a 50-year-old female, was referred to the endocrine outpatient clinic for the management of type 2 diabetes and reported a longstanding history of asymptomatic hypercalcaemia which had not been investigated previously. Investigation revealed hypercalcaemia; corrected calcium of 2.6 mmol/L (reference range: 2.21-2.52 mmol/L); PTH of 53.7ng/L (reference range: 15-65 ng/L) and an elevated 24-hour urine calcium of 10 mmol/24 (2.50-7.50 mmol/24hr) with positive genetic analysis and is managed conservatively. Despite sharing this novel mutation, these cases have different phenotypes and their natural history is yet to be determined. Two further relatives are currently undergoing investigation for hypercalcaemia and the family have been referred for genetic counselling.

CONCLUSION

Accurate diagnosis of FHH and differentiation from classic primary hyperparathyroidism can be challenging, however it is essential to avoid unnecessary investigations and parathyroid surgery. Genetic analysis may be helpful in establishing a diagnosis of FHH in light of the biochemical heterogeneity in this population and overlap with other causes of hypercalcaemia.

Analysis of Time to Diagnosis and Outcomes Among Adults With Primary Hyperparathyroidism

IMPORTANCE

Despite access to routine laboratory evaluation, primary hyperparathyroidism (PHP) remains underdiagnosed and undertreated.

OBJECTIVE

To determine the consequences associated with missed diagnoses and prolonged time to diagnosis and treatment of PHP.

DESIGN, SETTING, AND PARTICIPANTS

This is a retrospective cohort study of patients older than 40 years with 2 instances of hypercalcemia during 2010 to 2020 and 3 years of follow-up. Patients were recruited from 63 health care organizations in the TriNetX Research Network. Data analysis was performed from January 2010 to September 2020.

EXPOSURES

Elevated serum calcium.

MAIN OUTCOMES AND MEASURES

Existing symptoms and diagnoses associated with PHP (osteoporosis, fractures, urolithiasis, major depressive disorder, anxiety, hypertension, gastroesophageal reflux disease, malaise or fatigue, joint pain or myalgias, constipation, insomnia, polyuria, weakness, abdominal pain, headache, nausea, amnesia, and gallstones) compared in patients deemed high-risk and without a diagnosis and matched controls, and those who experienced times from documented hypercalcemia to diagnosis and diagnosis to treatment within or beyond 1 year.

RESULTS

There were 135 034 patients analyzed (96 554 women [72%]; 28 892 Black patients [21%] and 88 010 White patients [65%]; 3608 Hispanic patients [3%] and 98 279 non-Hispanic patients [73%]; mean [SD] age, 63 [10] years). Two groups without a documented diagnosis of PHP were identified as high risk: 20 176 patients (14.9%) with parathyroid hormone greater than or equal to 50 pg/mL and 24 905 patients (18.4%) with no parathyroid hormone level obtained or recorded explanation for hypercalcemia. High-risk patients experienced significantly increased rates of all associated symptoms and diagnoses compared with matched controls. Just 9.7% of those with hypercalcemia (13 136 patients) had a diagnosis of PHP. Compared with individuals who received a diagnosis within 1 year of hypercalcemia, those whose workup exceeded 1 year had significantly increased rates of major depressive disorder, anxiety, hypertension, gastroesophageal reflux disease, malaise or fatigue, joint pain or myalgias, polyuria, weakness, abdominal pain, and headache at 3 years. The rate of osteoporosis increased from 17.1% (628 patients) to 25.4% (935 patients) over the study period in the group with delayed diagnosis. Among those with a diagnosis, 5280 patients (40.2%) underwent parathyroidectomy. Surgery beyond 1 year of diagnosis was associated with significantly increased rates of osteoporosis and hypertension at 3 years after diagnosis compared with those treated within 1 year.

CONCLUSIONS AND RELEVANCE

Many patients were at high risk for PHP without a documented diagnosis. Complications in these patients, as well as those who received a diagnosis after prolonged workup or time to treatment, resulted in patient harm. System-level interventions are necessary to ensure proper diagnosis and prompt treatment of PHP.

Parathyroid adenoma presenting as chronic pancreatitis: A case report and literature review

BACKGROUND

Most patients with parathyroid adenomas are asymptomatic and rarely present with chronic pancreatitis (CP). Several studies have reported a positive association between primary hyperparathyroidism (PHPT) and pancreatitis. Parathyroidectomy is the definitive treatment for PHPT. IV bisphosphonates can be considered the drug of choice for bridge to surgery.

METHODS

We reported a 57-year-old female patient was admitted to the emergency room with left upper quadrant abdominal pain and a diagnosis of recurrent pancreatitis. Magnetic Resonance Cholangiopancreatography confirmed the diagnosis of CP. The patient had no common etiology of pancreatitis. Persistent hypercalcemia was noted despite administering intravenous fluids, and Calcitonin. Intravenous Pamidronate, a Bisphosphonate derivative, was also administered. Although calcium levels initially decreased, they were later found to rebound to previous levels.

RESULTS

A diagnosis of parathyroid adenoma and PHPT was made based on the elevated parathyroid hormone levels and cervical ultrasonography indicated right inferior parathyroid adenoma. Technetium-99m methoxy-isobutyl-isonitrile scintigraphy revealed a focal hot spot of tracer accumulation at the right lower thyroid bed. The patient underwent right lower parathyroidectomy smoothly and successfully. After right lower parathyroidectomy, she had normal serum calcium levels (9.2 mg/dL) and parathyroid hormone (16.1 pg/mL). There was no recurrent abdominal pain after the operation.

CONCLUSION

CP is a rare manifestation of parathyroid adenoma. When patients with a history of recurrent pancreatitis, without common causes of pancreatitis, present persistent elevated serum calcium levels, PHPT could be suspected.

Excluding familial hypocalciuric hypercalcaemia before surgery for primary hyperparathyroidism - a practical evaluation of urinary calcium using a retrospective cohort design

INTRODUCTION

Familial hypocalciuric hypercalcaemia (FHH) and primary hyperparathyroidism (PHPT) are both associated with raised serum calcium and parathyroid hormone (PTH) levels; the former should be excluded in patients undergoing surgery for the latter. Twenty-four-hour urinary calcium collections (24UCA) can be performed to quantify total calcium excreted; however, results of this method do not take into account factors such as kidney function. Current guidelines suggest measuring urine calcium to creatinine clearance ratio (CCCR) as the initial step. The aim of this study was to evaluate the use of CCCR and 24UCA in a cohort design, to reliably exclude FHH patients before surgery for PHPT.

METHODS

A retrospective cohort study of all patients having urine calcium investigations in a single centre, over a 2-year period was performed. Relevant biochemical data and recorded diagnoses were collected.

RESULTS

In total, 296 urine calcium measurements were included from 199 patients. Ten (5%) had genetically confirmed or suspected FHH, 171 (85.9%) had surgically proven or suspected PHPT and the remainder had other diagnoses. At a CCCR cut-off of ≤0.020, positive and negative predictive values (PPV and NPV) were 2.33% and 100%, respectively. At a cut-off of ≤0.015, NPV was maintained at 100% and PPV increased to 3.28%. Low 24UCA measurements (<2.5mmol/L/24h) generated a NPV for FHH of 95.2%.

CONCLUSION

A CCCR measurement below 0.020 should raise the possibility of FHH and genetic screening should be considered. 24UCA had a lower predictive power to exclude FHH (NPV), and measurements should be interpreted in the context of renal function.