A 10-year retrospective study of primary hyperparathyroidism in children

Variable presentation and outcomes of primary hyperparathyroidism in children and adolescents

OBJECTIVES

Primary hyperparathyroidism (PHPT) in paediatric and adolescent age group presents with some unique challenges for clinicians. While the disease in the adult counterparts presents with symptoms which are described quite extensively in literature, children/adolescents have manifestations which are quite different and severe compared to the former. The present case series aimed to highlight the peculiarities of presentation of PHPT in children and adolescents.

CASE PRESENTATION

In this case series, we present experience of 5 cases of PHPT in children and adolescents from our centre. We compared our data with the data already available in literature. We have also described salient presenting features of PHPT in individuals less than 19 years old previously reported in literature and pointed out the specificities of this disease at this age group.

CONCLUSIONS

PHPT in children and adolescents should be considered as a separate entity compared to that in adults, given its unique features, such as rachitic features, and severity of different presenting phenotypes. Persistence of rachitic features despite vitamin D correction, pancreatitis, bilateral nephrolithiasis and otherwise unexplained psychiatric abnormalities of insidious onset require greater clinical vigilance and serum/urine calcium testing to rule out this uncommon yet possible entity.

Primary Hyperparathyroidism due to Parathyroid Adenoma in Children and Adolescents

OBJECTIVE

In contrast to adults, primary hyperparathyroidism (PHPT) in children and adolescents is a rare endocrine disorder.

METHODS

A retrospective review of PHPT cases between 2005 and 2022 from a single tertiary university medical center, including clinical signs and symptoms, laboratory findings, radiological evaluation, treatment, and postoperative complications.

RESULTS

Ten children (mean age at diagnosis 16.3 ± 1.3 years) were diagnosed with PHPT. All patients were in late pubertal stages without sex predominance and 8 were symptomatic. Mean calcium level was 13.6 ± 2.5 mg/dL, and mean parathyroid hormone levels were 204.8 ± 163.1 pg/mL. Parathyroid adenoma was confirmed by the postsurgical pathology results.

CONCLUSIONS

PHPT in children and adolescents is often symptomatic and more severe than adults. The main cause is single parathyroid adenoma. Associated hypercalcemic syndromes were not found. Patients were cured after surgical removal of the adenoma without significant postoperative complications and no recurrence during 10.4 ± 5.9 years follow-up.

Pediatric primary hyperparathyroidism: Surgical pathology and long-term outcomes in sporadic and familial cases

BACKGROUND

Primary Hyperparathyroidism (PHPT) is rare in pediatric patients. Data regarding surgical outcomes are scarce.

METHODS

Single-center retrospective review (1994-2020) of patients ≤21 years undergoing surgery for PHPT.

RESULTS

66 patients were identified (61% female, 17 ± 3 years). 71% of patients were symptomatic at diagnosis. 32% of patients had known familial syndromes, most commonly MEN-1. 23% of patients without a known mutation had genetic testing, 22% positive. 56% of the total and 19% of the familial cohort underwent focused exploration. Single gland disease was found in 19% of familial vs 85% of sporadic cases, p < 0.00001. Persistence was 9%, all in the sporadic group, p = 0.11. Recurrence was 15%: 38% in the familial vs 2% in the sporadic groups, p=0.0004. Time to recurrence was 59 months (Q1-38, Q3-95), familial 61 vs 124 months sporadic, p=0.001.

CONCLUSION

Pediatric PHPT is frequently sporadic, although 5% of apparent sporadic cases are secondary to syndromes. Familial cases have higher rates of recurrence, requiring closer follow-up.

Features of the diagnosis of primary hyperparathyroidism in children

Background. Primary hyperparathyroidism (PHPT) is a rare pathology in pediatric and adolescent patients. Collection, analysis and generalization of the literature data and experience of the leading clinics allow to develop unified, statistically substantiated approaches to diagnostics and surgical treatment of this group of patients.

Material and methods. The article presents a retrospective analysis of 17 cases of PHPT in children and adolescents aged from 6 to 18 years operated on in the department of Surgery of St.-Petersburg State Pediatric Medical University in the period from 1973 till 2021. Among those operated there were 10 girls and 7 boys, the M:F ratio was 1:1.4. The mean age of the patients was 12,9±0,71 years.

Results and discussion. The main criteria of the disease diagnosis were elevated blood calcium and parathormone levels, excessive urinary calcium secretion. Manifest forms of the disease were diagnosed in 10 (58,8%) of 17 children. In 3 (17,6%) cases the parathyroid neoplasms were accompanied neither by clinical, nor laboratory manifestations of the disease and were regarded as incidentalomas. Another 4 (23.5%) patients had only laboratory changes (hypercalcemia and hyperparathyrinaemia) that manifested themselves preoperatively. These observations were referred to the asymptomatic form of PHPT.

In 7 (41.2%) cases parathyroid adenomas were found and removed during surgeries for various thyroid diseases (thyroid cancer in 5 cases, diffuse toxic goiter in 1 case). An incidental finding of parathyroid adenoma was during prophylactic thyroidectomy for Sipple syndrome.

A radioisotope method proved to be the most informative way to localize parathyroid tumors.

Conclusion. The diagnosis of the disease in manifest sporadic cases does not differ from that in adults. Genetic study is indicated in the presence of a family history of multiple involvement of the parathyroid glands. Surgical treatment with removal of parathyroid tumor is the main method, which allows to achieve complete recovery. 

Primary hyperparathyroidism from ectopic parathyroid adenoma in a 12-year-old with slipped capital femoral epiphysis

Primary hyperparathyroidism has been reported in pediatric patients presenting with slipped capital femoral epiphysis (SCFE), but never in patients with ectopic parathyroid adenoma. A 12-year-old boy with obesity and autism spectrum disorder presented with a limp and was found to have bilateral SCFE. Calcium was elevated to 12.3 mg/dL with parathyroid hormone (PTH) of 1191 pg/mL. Neck ultrasound revealed no parathyroid adenoma. He was discharged following bilateral surgical pinning with plans for outpatient workup. Repeat labs 5 days later demonstrated calcium had risen to 16.7 mg/dL. Technetium-99m sestamibi scintigraphy and a computed tomography scan revealed a 2.7 × 1.6 × 1.9 cm intrathymic mediastinal lesion. He underwent a thoracoscopic resection of the mass, and intraoperative PTH levels fell appropriately. Pathology revealed a parathyroid adenoma. Postoperatively, the patient developed hungry bone syndrome followed by normocalcemic secondary hyperparathyroidism which resolved with high-dose vitamin D supplementation. Primary hyperparathyroidism presenting as SCFE in a pediatric patient has been reported in 13 previous cases. This is the first reported case of bilateral SCFE arising from an ectopic parathyroid adenoma. Thoracoscopic resection is a relatively new approach in pediatrics. Primary hyperparathyroidism can be associated with SCFE, especially bilateral, and should be considered in patients with traditional risk factors for SCFE. Pediatric patients with primary hyperparathyroidism and negative neck imaging should be further evaluated for ectopic parathyroid adenomas with nuclear medicine or cross-sectional imaging that includes the head, neck, and mediastinum. Thoracoscopic resection can be considered in pediatric patients with mediastinal ectopic parathyroid adenoma.

Pediatric hyperparathyroidism: review and imaging update

Hyperparathyroidism, due to increased secretion of parathyroid hormones, may be primary, secondary or tertiary. Most pediatric patients with sporadic primary hyperparathyroidism will be symptomatic, presenting with either end-organ damage or nonspecific symptoms. In younger patients with primary hyperparathyroidism, there is a higher prevalence of familial hyperparathyroidism including germline inactivating mutations of the calcium-sensing receptor genes that result in either neonatal severe hyperparathyroidism or familial hypocalciuric hypercalcemia. Parathyroid scintigraphy and ultrasound are complementary, first-line imaging modalities for localizing hyperfunctioning parathyroid glands. Second-line imaging modalities are multiphase computed tomography (CT) and magnetic resonance imaging. In pediatrics, multiphase CT protocols should be adjusted to optimize radiation dose. Although, the role of these imaging modalities is better established in preoperative localization of hyperfunctioning parathyroid glands in primary hyperparathyroidism, the same principles apply in secondary and tertiary hyperparathyroidism. In this manuscript, we will review the embryology, anatomy, pathophysiology and preoperative localization of parathyroid glands as well as several subtypes of primary familial hyperparathyroidism. While most of the recent imaging literature centers on adults, we will focus on the issues that are pertinent and applicable to pediatrics.

Ectopic Parathyroid Adenoma in an 11-Year-Old Girl: Case Report and Literature Review

Objective

Primary hyperparathyroidism secondary to an ectopic parathyroid adenoma is rare among children and adolescents.

Methods

We describe the case of an 11-year-old girl with incidentally diagnosed primary hyperparathyroidism secondary to an intrathymic parathyroid adenoma and performed a review of the related literature.

Results

^99mTechnetium sestamibi single-photon emission computerized tomography/computed tomography and 4-dimensional computed tomography confirmed the ectopic location of the adenoma. The patient underwent thoracoscopic thymectomy and remained normocalcemic with elevated parathyroid hormone showing a downward trend. Parathyroid hormone normalized 18 months after successful parathyroidectomy.

Conclusion

We review the case of a rare mediastinal parathyroid adenoma in a pediatric patient and summarize the epidemiologic profile, diagnosis, and management of similar pediatric cases.

"Primary Hyperparathyroidism (PHPT) in Children: Two Case Reports and Review of the Literature"

Primary hyperparathyroidism (PHPT) is a rare disorder in children and adolescents. Typical biochemical features are hypercalcemia and hypophosphatemia, but the clinical features can be heterogeneous, and in some cases, symptoms are vague and nonspecific, leading to misdiagnosis or late diagnosis. Herein, we report two cases of PHPT in pediatric age with different presenting symptoms, pain in the foot, and progressive alteration of the gait in the first case and recurrent abdominal pain with emotional lability in the second. Biochemical and radiological assessment confirmed PHPT. Both cases were treated surgically as definitive treatment, but in the second case, previous medical treatment with cinacalcet, a calcimimetic agent, was required to reduce serum PTH and calcium levels. After surgery, despite conventional treatment with calcium and calcitriol, case 1 developed a hungry bone syndrome. The analysis of the MEN-1 (Multiple Endocrine Neoplasia) gene was negative in both cases. A diagnosis of PHPT should be considered when children or adolescents present bone pain with radiological imaging of osteolytic lesion and biochemical feature of hypercalcemia associated with hypophosphatemia. In PHPT, the gold standard treatment is represented by surgery followed by strict postoperative endocrine monitoring to maintain adequate homeostasis of calcium and bone metabolism.

Why is primary hyperparathyroidism more severe in children?

The disease presentation of primary hyperparathyroidism (PHPT) is more severe in children. We hypothesize that this difference in disease presentation is a result of several factors including a delay in diagnosis, age-related differences in calcium metabolism and bone turnover, and the influence of the growth hormone (GH)/insulin growth factor-1 (IGF-1) axis. Only the first two explanations for the heightened disease severity of PHPT in children have been previously discussed in the literature. In regards to the potential role GH and IGF-1 may play in this disparity, previous studies have documented decreases in GH and IGF-1 secretion in symptomatic adult PHPT patients potentially influencing the severity of the patients' disease presentation. While these studies have yet to be replicated in the pediatric population, given that both GH and IGF-1 are important for the achievement of peak bone mass in young individuals, it is logical to infer that the GH/IGF-1 axis may be partly responsible for the severe presentation of PHPT in children.

Pediatric Primary Hyperparathyroidism: Experience in a Tertiary Care Referral Center in a Developing Country Over Three Decades

BACKGROUND

There is limited experience in managing pediatric primary hyperparathyroidism (PHPT). The aim of this study was to analyze the clinical presentation and outcome of surgery in children with PHPT managed at a tertiary referral center.

METHODS

This retrospective study (September 1989-August 2019) consisted of 35 pediatric PHPT patients (< 18 years) who underwent parathyroidectomy. Clinico-pathologic profile and outcome were noted.

RESULTS

The mean age of cohort was 15.2±2.9 years and girls outnumbered boys (M:F = 1:1.9). Familial and symptomatic disease was noted in 8.5 and 94.3% cases, respectively. Skeletal manifestations (83%) were the commonest followed by renal (29%). Fifty-four percent children had skeletal fractures, and 23% were bed-ridden. Among rare manifestations, hypercalcemic crisis, recurrent pancreatitis and stigmata of rickets were observed in 2.8, 11.4 and 14.2% children, respectively. Mean calcium concentration was 12.1 ± 2.0 mg/dl and PTH 91.8 ± 66.5 pmol/L. The sensitivity of preoperative imaging in parathyroid localization was 91.4%. Minimally invasive parathyroidectomy (MIP) was performed in 40% cases. Parathyroid adenoma was observed in 91.4% patients, whereas remaining had hyperplasia. Thirty-four percent suffered from Hungry bone syndrome in postoperative period. The cure rate following primary surgery was 97%. One child with persistent PHPT had successful re-operation. Median follow-up was 5 (1-17) years, and no recurrence or familial disease was revealed during this period.

CONCLUSION

Majority of pediatric patients present with symptomatic PHPT. Despite relatively high incidence of familial disease select pediatric patients can undergo successful MIP.

A case of primary hyperparathyroidism due to an intrathymic ectopic parathyroid adenoma in a 15-year-old boy

Hypercalcemia due to primary hyperparathyroidism (PHPT) is uncommon in children. PHPT is typically caused by a single parathyroid adenoma. Ectopic parathyroid adenomas account for 6%-16% of all parathyroid adenomas and are rare in children but should be considered in cases that present with hypercalcemia. We report the case of a 15-year-old boy with PHPT due to an intrathymic ectopic parathyroid adenoma. Neck ultrasonography and Tc-99m-sestamibi (MIBI) scanning with single-photon emission computed tomography/computed tomography (SPECT/CT) revealed ectopic parathyroid adenoma in the thymus. Video-assisted thoracoscopic surgery was performed to remove the ectopic parathyroid adenoma. Pathology showed intrathymic ectopic parathyroid adenoma. After surgery, the patient's serum calcium level immediately normalized. Intact parathyroid hormone (iPTH) and alkaline phosphatase levels returned to normal ranges within 3 months. Delayed diagnosis of PHPT can cause end-organ damage; a timely diagnosis is especially critical to preserve bone and renal function. If ectopic parathyroid adenomas are well localized in preoperative imaging evaluation and intraoperative iPTH level decreases after resection, ectopic parathyroidectomy without bilateral neck exploration may be performed to avoid unnecessary morbidity.

Primary hyperparathyroidism due to ectopic parathyroid adenoma in an adolescent: a case report and review of the literature

PURPOSE

Primary hyperparathyroidism (PHPT) is a common endocrine disorder and is usually diagnosed in adults. PHPT due to ectopic parathyroid adenoma in adolescents is rare.

METHODS

We describe the case of a 15-year-old boy with PHPT due to ectopic parathyroid adenoma. A review of the literature of PHPT in adolescents was performed, focusing on etiology, clinical presentation, preoperative localization methods, pathology, and treatment.

RESULTS

The patient was successfully treated with surgery and was followed up for 5 years with no signs or symptoms of hyperparathyroidism. By reviewing the literature, only seven cases of PHPT associated with ectopic parathyroid lesions in adolescents have been reported. Parathyroidectomy is the only known curative treatment. Accurate preoperative localization of the target lesion is critical.

CONCLUSIONS

This study should raise awareness of the diagnosis and treatment of PHPT due to ectopic parathyroid adenoma/carcinoma in adolescents.

Comparative Diagnostic Performance of Ultrasonography and 99mTc-Sestamibi Scintigraphy for Parathyroid Adenoma in Primary Hyperparathyroidism; Systematic Review and Meta- Analysis

Objective:

Ultrasonography (US) and parathyroid scintigraphy (PS) with 99mTc-MIBI are common methods for preoperative localization of parathyroid adenomas but there discrepancies exist with regard to diagnostic accuracy. The aim of the study was to compare PS and US for localization of parathyroid adenoma with a systematic review and meta-analysis of the literature.

Methods:

Pub Med, Scopus (EMbase), Web of Science and the reference lists of all included studies were searched up to 1st January 2016. The search strategy was according PICO characteristics. Heterogeneity between the studies was accounted by P < 0.1. Point estimates were pooled estimate of sensitivity, specificity and positive predictive value of SPECT and ultrasonography with 99% confidence intervals (CIs) by pooling available data. Data analysis was performed using Meta-DiSc software (version 1.4).

Results:

Among 188 studies and after deletion of duplicated studies (75), a total of 113 titles and abstracts were studied. From these, 12 studies were selected. The meta-analysis determined a pooled sensitivity for scintigraphy of 83% [99% confidence interval (CI) 96.358 -97.412] and for ultra-sonography of 80% [99% confidence interval (CI) 76-83]. Similar results for specificity were also obtained for both approache.

Conclusion:

According this meta- analysis, there were no significant differences between the two methods in terms of sensitivity and specificity. There were overlaps in 99% confidence intervals. Also features of the two methods are similar.

Primary hyperparathyroidism in Chinese children and adolescents: A single-centre experience at Peking Union Medical College Hospital

OBJECTIVE

Primary hyperparathyroidism (PHPT) in children is thought to be extremely rare. Our study aimed to summarize the clinical characteristics and the molecular genetics in patients with paediatric PHPT in China.

DESIGN

Retrospective observational study.

METHODS

A total of 59 paediatric PHPT patients (onset age <18 years) admitted to Peking Union Medical College Hospital from 1975 to 2015 were retrospectively identified. A group of 118 adult PHPT patients who presented during the same period were selected for comparing clinical characteristics between the two groups. Germline mutation analyses of the MEN1, CDC73, RET, CDKN1B and CaSR genes were performed in 24 patients.

RESULTS

Only one paediatric patient (1.7%) with PHPT was asymptomatic. Bone involvement, urolithiasis, acute pancreatitis and hypercalcaemic crisis were present in 86.4%, 39.0%, 6.8% and 10.2% of cases, respectively. Paediatric PHPT presented more commonly with rickets/osteomalacia compared to adult PHPT. Fifty-seven paediatric patients underwent surgery. Adenoma, hyperplasia, atypical adenoma and carcinoma occurred in 80.7%, 10.5%, 7.0% and 1.8% of cases, respectively. Of the 24 paediatric patients screened for genetic mutations, two patients were found to carry MEN1 mutations and six were found to carry CDC73 mutations. The mutation rate was 22.2% (4/18) in sporadic patients.

CONCLUSION

Unlike adults with PHPT, most paediatric PHPT were symptomatic. Rickets/osteomalacia was more common in paediatric patients than in their adult counterparts. Paediatric PHPT patients can be treated successfully with surgical intervention. Genetic screening of the MEN1 and CDC73 genes for mutations should be recommended in paediatric patients due to a relatively high mutation rate.

Outcomes of Parathyroidectomy in Patients with Primary Hyperparathyroidism: A Systematic Review and Meta-analysis

BACKGROUND

Parathyroidectomy is a definitive treatment for primary hyperparathyroidism. Patients contemplating this intervention will benefit from knowledge regarding the expected outcomes and potential risks of the currently available surgical options.

PURPOSE

To appraise and summarize the available evidence regarding benefits and harms of minimally invasive parathyroidectomy (MIP) and bilateral neck exploration (BNE).

DATA SOURCES

A comprehensive search of multiple databases (MEDLINE, EMBASE, and Scopus) from each database's inception to September 2014 was performed.

STUDY SELECTION

Eligible studies evaluated patients with primary hyperparathyroidism undergoing MIP or BNE.

DATA EXTRACTION

Reviewers working independently and in duplicate extracted data and assessed the risk of bias.

DATA SYNTHESIS

We identified 82 observational studies and 6 randomized trials at moderate risk of bias. Most of them reported outcomes after MIP (n = 71). Using random-effects models to pool results across studies, the cure rate was 98 % (95 % CI 97-98 %, I (2) = 10 %) with BNE and 97 % (95 % CI 96-98 %, I (2) = 86 %) with MIP. Hypocalcemia occurred in 14 % (95 % CI 10-17 % I (2) = 93 %) of the BNE cases and in 2.3 % (95 % CI 1.6-3.1 %, I (2) = 87 %) with MIP (P < 0.001). There was a statistically significant lower risk of laryngeal nerve injury with MIP (0.3 %) than with BNE (0.9 %), but similar risk of infection (0.5 vs. 0.5 %) and mortality (0.1 vs. 0.5 %).

LIMITATIONS

The available evidence, mostly observational, is at moderate risk of bias, and limited by indirect comparisons and inconsistency for some outcomes (cure rate, hypocalcemia).

CONCLUSION

MIP and BNE are both effective surgical techniques for the treatment of primary hyperparathyroidism. The safety profile of MIP appears superior to BNE (lower rate of hypocalcemia and recurrent laryngeal nerve injury).

Outcomes of minimally invasive parathyroidectomy in pediatric patients with primary hyperparathyroidism owing to parathyroid adenoma: A single institution experience

BACKGROUND

Guidelines for treatment of primary hyperparathyroidism (PHPT) in young patients recommend surgery. Outcomes of minimally invasive parathyroidectomy (MIP) are well established in adults, but not in pediatric patients.

OBJECTIVE

The objective of the study is to determine effectiveness of preoperative imaging and MIP aided by intraoperative PTH (ioPTH) measurement in children with primary hyperparathyroidism (PHPT).

METHODS AND DESIGN

This is a retrospective chart review of diagnostic and follow-up data up to 12months post-MIP of patients with PHPT who underwent parathyroidectomy at the Children's Hospital of Philadelphia between January 1, 2009 and March 31, 2015.

RESULTS

Data were available for 16 of 17 patients age 8-17years (11 females, 6 males): 2 had ectopic intrathymic adenomas while 14 had eutopic adenomas. Fifteen patients had ioPTH, including 14 who underwent MIP, defined as a 2cm central neck incision. All patients with data at 6months postparathyroidectomy (13/16) showed normal PTH and calcium. Ultrasound and sestamibi scans had a combined sensitivity of 87.5%.

CONCLUSIONS

MIP is an appropriate alternative to standard neck exploration in pediatric patients with PHPT with a single parathyroid adenoma. ioPTH is especially useful to confirm cure and limit surgical exploration when imaging studies are negative. Sestamibi scans and ultrasound are complementary studies.

A meta-analysis comparing the biochemistry of primary hyperparathyroidism in youths to the biochemistry of primary hyperparathyroidism in adults

CONTEXT

The distinctive presentation of primary hyperparathyroidism (PHPT) in adults and youths suggest that PHPT is a fundamentally different disease in these two groups.

OBJECTIVE

To understand the difference in PHPT between adults and youths we compared the biochemistry of PHPT in these two groups.

DESIGN

This study is a systematic review and meta-analysis of retrospective studies published 1966-2014 on PHPT.

DATA SOURCES

All studies were obtained through Medline (1966-2014).

STUDY SELECTION AND DATA EXTRACTION

Only studies that included post-surgical subjects and that explicitly described biochemical results from more than one decade were included. Data were extracted from each article to generate the mean and SE for multiple biochemical parameters.

DATA SYNTHESIS

We analyzed 16 studies describing 268 unique youths and 2405 adults with PHPT. Youths with PHPT had significantly (P < .05) greater serum and urinary calcium than adults with PHPT (3.2 ± 0.1 mmol/L vs 2.8 ± 0.0 mmol/L for serum calcium, and 9.95 ± 1.26 mmol/d vs 7.15 ± 0.56 mmol/d for urine calcium, [mean ± SEM]). There were no significant differences in serum intact PTH, phosphorus, or alkaline phosphatase.

CONCLUSIONS

Juvenile PHPT has greater hypercalcemia and hypercalciuria than adult PHPT at similar concentrations of serum intact PTH. These observations suggest that there are differences in the pathophysiology of PHPT between juvenile and adult patients who reflect an apparent decrease in the sensitivity of the parathyroid adenoma to negative feedback by calcium and increased sensitivity of target tissues to the effects of PTH.

Intraoperative parathyroid hormone monitoring corroborates the success of parathyroidectomy in children

OBJECTIVE

To assess the efficacy of intraoperative parathyroid hormone (PTH) monitoring in evaluating the outcome of parathyroidectomy in pediatric patients.

METHODS

Intraoperative PTH monitoring during parathyroidectomy was performed in five children (3M, 2F); three had parathyroid adenomas (single gland disease) and two had primary hyperplasia. One patient had undergone two previous surgical interventions to remove the parathyroid glands, but the PTH levels had remained high with persistence of symptoms. Immunoradiometric analysis was used for PTH measurements. Preoperative PTH values were obtained to monitor the baseline levels. Serum samples were collected 20 minutes after removal of the adenoma/parathyroid gland(s) and PTH levels were compared with preoperative values. Specimens were also confirmed by frozen sectional examination.

RESULTS

Mean age of the patients was 11 years (range: 3 months-16 years). Mean preoperative PTH values were 633.3±579 pg/mL (range: 143-1300 pg/mL). Intraoperative values decreased to 18.7±5.5 pg/mL (range: 8-27 pg/mL) following removal of the gland(s). Normal calcium levels were achieved with adequate management following surgery. One patient (with multiple surgeries and found to have an ectopic parathyroid gland) had hungry bone syndrome after the operation and was treated successfully. There were no major complications. All patients maintained normal calcium/phosphorus levels in the follow-up period, ranging from 2 to 5 years.

CONCLUSION

An ectopic parathyroid gland or another undetected adenoma can be overlooked during surgery. Owing to the short life of the hormone, intraoperative PTH monitoring to determine PTH clearance proved to be a feasible marker for adequacy and safety of surgery and "cure".

Parathyroid conditions in childhood

This review of parathyroid surgery in children will briefly discuss parathyroid gland embryology and anatomy before focusing on the pathophysiology, clinical presentation, and treatment of hyperparathyroidism in children. Hyperparathyroidism (HPT) is the overproduction of PTH and it is rare in children, with an incidence of 2-5 per 100,000. This rarity means that the principles of caring for children with parathyroid disease are largely extrapolated from the richer adult experience; however, the unique pediatric aspects of parathyroid problems and their surgical treatment, including presentation, imaging, operative approach, and complications, will be considered.

Hyperparathyroidism two years after radioactive iodine therapy in an adolescent male

Primary hyperparathyroidism is a very rare complication following radioactive iodine therapy. There is typically a latency period of more than a decade following radiation exposure and, therefore, it is observed almost exclusively in adults. Consequently, pediatricians are not aware of the association. We present a case of primary hyperparathyroidism due to a solitary parathyroid adenoma occurring in an adolescent male two years following radioactive iodine treatment for papillary thyroid carcinoma. Periodic screening of serum calcium following ablative doses of radioactive iodine for thyroid cancer may be justified even in adolescents.

Radioguided parathyroidectomy effective in pediatric patients

BACKGROUND

Radioguided parathyroidectomy (RGP) has been shown to be effective in adult patients with hyperparathyroidism (HPT), but the utility of RGP in pediatric patients has not been systematically examined. It is not known if adult criteria for radioactive counts can accurately detect hyperfunctioning parathyroid glands in pediatric patients. The purpose of our study was to determine the utility of RGP in children with primary HPT.

MATERIALS AND METHODS

A retrospective review of our prospectively maintained single-institution database for patients who underwent a RGP for primary HPT identified 1694 adult and 19 pediatric patients aged 19 y or younger. From the adult population, we selected a control group matched three to one for gland weight and gender and compared pre- and postoperative laboratory values, surgical findings, pathology, and radioguidance values between the control and the pediatric groups.

RESULTS

Excised glands from pediatric patients were smaller than those in the total adult population (437 ± 60 mg versus 718 ± 31 mg, P = 0.0004). When controlled for gland weight, ex vivo counts as a percentage of background were lower in the pediatric group (51% ± 5% versus 91% ± 11%, P = 0.04). However, ex vivo radionuclide counts >20% of the background were found in 100% of pediatric patients and 95% of the adult-matched control group.

CONCLUSIONS

All pediatric patients met the adult detection criteria for parathyroid tissue removal when a RGP was performed, and 100% cure was achieved. We conclude that RGP is a useful treatment option for pediatric patients with primary HPT.

Primary hyperparathyroidism in children and adolescents

Primary hyperparathyroidism (PHPT) is a common endocrine disorder in adults in whom the typical presentation is incidentally discovered as asymptomatic hypercalcemia. PHPT is much less common in children and adolescents, but has greater morbidity in this age group, as most young patients with PHPT will have symptomatic hypercalcemia or complications such as kidney stones, abdominal pain, and skeletal fragility. An important feature of PHPT in younger patients is the relatively high prevalence of germline inactivating mutations of the CASR gene, which encodes the calcium-sensing receptor. Biallelic CASR mutations cause neonatal severe hyperparathyroidism, a life-threatening condition that presents within days of life with marked hypercalcemia, respiratory distress, failure to thrive, and skeletal demineralization. By contrast, more common heterozygous CASR mutations are generally associated with a benign variant of PHPT termed familial hypocalciuric hypercalcemia. Appropriate management of PHPT in children and adolescents requires distinction between familial hypocalciuric hypercalcemia, which generally requires no specific treatment, and other forms of PHPT that are best treated by parathyroidectomy.