Single Gland, Ectopic Location: Adenomas are Common Causes of Primary Hyperparathyroidism in Children and Adolescents

Adolescent primary hyperparathyroidism

Adolescent primary hyperparathyroidism (PHPT) is a rare endocrine disorder bearing distinctions from the adult form. This review examines its unique aspects, focusing on clinical presentation, genetic etiologies, genotype-phenotype correlations, and therapeutic management. Adolescent PHPT often has a genetic basis, whether familial, syndromic, or apparently sporadic, and identifying the underlying genetic cause is important for patient care. The clinical presentation is predominantly symptomatic worldwide. Unique manifestations in this age group include rickets, short stature, and slipped capital femoral epiphysis. Genotype-specific differences are evident in the adolescent PHPT characteristics. Diagnostic evaluation requires careful interpretation of biochemical and dual-energy X-ray absorptiometry findings using age and gender-specific reference ranges, with targeted screening for syndrome-associated neoplasms. Surgery remains the cornerstone of management. Current knowledge gaps in their management include treatment protocols for multiple endocrine neoplasia type 1-associated PHPT, the efficacy and safety of nonsurgical options, and long-term post-surgical outcomes.

Case report: a rare case of primary hyperparathyroidism due to an intrathymic ectopic parathyroid adenoma incidentally diagnosed in a 15-year-old girl

Primary hyperparathyroidism (PHPT) due to ectopic parathyroid adenoma is a rare case of hypercalcemia in the pediatric population. Herein, a rare case of PHPT due to ectopic intrathymic parathyroid adenoma was described in an asymptomatic 15-year-old girl who had incidental diagnosis based on laboratory abnormalities but experienced a 3-month postoperative course of persistently elevated parathyroid hormone (PTH) and hypercalcemia following the initial unsuccessful parathyroidectomy operation carried out in a non-parathyroid expert center. The curative surgical treatment was accomplished only after the patient was reoperated with video-assisted thoracoscopic surgery (VATS) thymectomy by the surgeon experienced in parathyroid surgery with implementation of the combined imaging modalities for accurate localization of ectopic adenoma including 99mTc sestamibi (MIBI) plus neck and thoracic computed tomography (CT) and the appropriate surgical strategies including intraoperative intact PTH monitoring and frozen section diagnosis. Before the reoperation (VATS thymectomy), laboratory findings showed elevated PTH (1,171 ng/L; reference range: 21.80 ng/L-87.5 ng/L) and hypercalcemia (13.4 mg/dL; reference range: 8.4 mg/dL-10.2 mg/dL). The preoperative PTH levels were 94 ng/L at 5 min after thymectomy and 78 ng/L at 10 min. The PTH and calcium levels were 54.3 ng/L and 8.47 mg/dL, respectively, on postoperative day 1 and were 34.2 ng/L and 8.1 mg/dL on postoperative day 2. The patient was discharged on postoperative day 2 without any complications. In conclusion, our findings indicate the likelihood of isolated primary hyperparathyroidism to be incidentally diagnosed based solely on laboratory abnormalities with no specific clinical manifestations in the pediatric age. In addition, using combined imaging modalities (such as MIBI and CT) in accurate localization of ectopic parathyroid adenoma and implementation of surgery by experienced surgeons along with intraoperative intact PTH monitoring and frozen section diagnosis seem crucial to ensure the curative surgical treatment.

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.

Pediatric Neuroendocrine Neoplasia of the Parathyroid Glands: Delving into Primary Hyperparathyroidism

Our objective was to overview the most recent data on primary hyperparathyroidism (PHP) in children and teenagers from a multidisciplinary perspective. Methods: narrative review based on full-length, English-language papers (from PubMed, between January 2020 and July 2023). Results: 48 papers (14 studies of ≥10 subjects/study, and 34 case reports/series of <10 patients/study). Study-sample-based analysis: except for one case-control study, all of the studies were retrospective, representing both multicenter (n = 5) and single-center (n = 7) studies, and cohort sizes varied from small (N = 10 to 19), to medium-sized (N = 23 to 36) and large (N = 63 to 83); in total, the reviewed studies covered 493 individuals with PHP. Case reports/series (n = 34, N = 41): the mean ages studied varied from 10.2 to 14 years in case reports, and the mean age was 17 years in case series. No clear female predominance was identified, unlike that observed in the adult population. Concerning the assessments, there were four major types of endpoints: imaging data collection, such as ultrasound, 99mTc Sestamibi, or dual-phase computed tomography (CT); gene testing/familial syndrome identification; preoperative findings; and exposure to surgical outcome/preoperative drugs, like cinacalcet, over a 2.2-year median (plus two case reports of denosumab used as an off-label calcium-lowering agent). Single-gland cases (representing 85% of sporadic cases and 19% of genetic PHP cases) showed 100% sensitivity for neck ultrasounds, with 98% concordance with 99mTc Sestamibi, as well as a 91% sensitivity for dual-phase CT, with 25% of the lesions being ectopic parathyroids (mostly mediastinal intra-thymic). Case reports included another 9/41 patients with ectopic parathyroid adenomas, 3/41 with parathyroid carcinomas, and 8/41 subjects with brown tumors. Genetic PHP (which has a prevalence of 5-26.9%) mostly involved MEN1, followed by CDC73, CASR, RET, and CDKN1B, as well as one case of VHL. Symptomatic PHP: 70-100% of all cases. Asymptomatic PHP: 60% of genetic PHP cases. Renal involvement: 10.5% of a cohort with genetic PHP, 71% of sporadic PHP cases; 50% (in a cohort with a mean age of 16.7), 29% (in a cohort with a mean age of 15.2); 0% (in infancy) to 50-62% (in teenagers). Bone anomalies: 83% of the children in one study and 62% of those in two other studies. Gastrointestinal issues: 40% of one cohort, but the data are heterogeneous. Cure rate through parathyroidectomy: 97-98%. Recurrent PHP: 2% of sporadic PHP cases and 38% of familial PHP cases. Hungry bone syndrome: maximum rate of 34-40%. Case reports identified another 7/41 subjects with the same post-parathyroidectomy condition; a potential connection with ectopic presentation or brown tumors is suggested, but there are limited data. Minimally invasive thoracoscopic approaches for ectopic tumors seemed safe. The current level of statistical evidence on pediatric PHP qualifies our study- and case-sample-based analysis (n = 48, N = 534) as one of the largest of its kind. Awareness of PHP is the key factor to benefit our young patients.

Can we skip technetium-99 m sestamibi scintigraphy in pediatric primary hyperparathyroidism patients with positive neck ultrasound results?

BACKGROUND

Parathyroidectomy is the only curative treatment for primary hyperparathyroidism (PHPT). Ultrasound (US) and technetium-99 m sestamibi (99mTc-MIBI) scintigraphy are recommended as the first-line localization imaging modalities for PHPT in adults, but the value of preoperative imaging in pediatric patients has not been reported.

OBJECTIVE

To evaluate the added value of 99mTc-MIBI scintigraphy in pediatric PHPT patients with positive ultrasound results.

MATERIALS AND METHODS

Pediatric patients (≤18 years old) who were diagnosed with PHPT and underwent surgical treatment in Peking Union Medical College Hospital between January 2003 and January 2021 were included in this study. Demographic and clinical characteristics, preoperative localization US, 99mTc-MIBI scintigraphy and pathology results were collected. Preoperative localization results were evaluated by comparison with surgical and pathological findings.

RESULTS

There were 32 pediatric PHPT patients with median age of 14.7 ± 2.5 years who all proved to have single-gland disease without ectopic lesions. The median lesion size was 2.85 cm (range 1.0-5.8 cm). All patients underwent US and 99mTc-MIBI scintigraphy. Neck US demonstrated 100% sensitivity. Of 32 patients with a positive US, 99mTc-MIBI scintigraphy was concordant in 30 (93.8%). In 2 patients (6.3%), US reported suspected multigland disease, which was correctly diagnosed by 99mTc-MIBI scintigraphy as single lesions.

CONCLUSION

In pediatric PHPT patients, US achieved high sensitivity for preoperative localization. 99mTc-MIBI scintigraphy for pediatric patients with positive US results would not increase the sensitivity. Implementation of 99mTc-MIBI scintigraphy could increase the specificity in pediatric patients with multigland disease suspected by US.

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.

Dual-phase computed tomography for localization of parathyroid lesions in children and adolescents with primary hyperparathyroidism

BACKGROUND

Childhood and adolescent primary hyperparathyroidism (PHPT) is a rare disease caused by single adenomas in 65-94% of patients. In this patient group, there is no data on computed tomography (CT) for pre-operative parathyroid localization that may facilitate focused parathyroidectomy.

METHODS

Two radiologists reviewed dual-phase (nonenhanced and arterial) CT images of twenty-three operated children and adolescents [20:single-gland disease(SGD), 3:multi-glandular disease(MGD)] with proven histopathological PHPT. Percentage arterial enhancement (PAE) was calculated as [100*{arterial-phase Hounsfield unit (HU)-nonenhanced phase HU}/nonenhanced HU] of the parathyroid lesion(s), thyroid, and lymph node.

RESULTS

Dual-phase CT lateralized 100%, localized to the correct quadrant/site 85% SGD (including 3/3 ectopic), and identified 1/3 MGD. PAE (cutoff ≥ 112.3%) was sensitive (91.3%) and specific (99.5%) in distinguishing parathyroid lesions from local mimics (P<0.001). The average effective dose was 3.16±1.01mSv, comparable to the planar/single photon emission CT (SPECT) Technetium 99m(Tc)-sestamibi and choline positron emission tomography (PET)/CT scans. Solid-cystic morphology identified in 4 patients harboring pathogenic germline variants (3:CDC73, 1:CASR) may serve as a radiological clue to molecular diagnosis. Nineteen out of 20 (95%) patients with SGD who had undergone single gland resection based on pre-operative CT findings were in remission over a median follow-up of 18 months.

CONCLUSION

As most children/adolescents with PHPT have SGD, dual-phase CT protocols which reduce the effective radiation dose with high localization sensitivity for single parathyroid lesions may be a sustainable pre-operative imaging modality in this patient group.

Clinical Profile of Parathyroid Adenoma in Children and Adolescents: A Single-Center Experience

OBJECTIVE

Parathyroid adenoma is less common than in adulthood, but its morbidity is higher in children. We aimed to evaluate the clinical characteristics of parathyroid adenoma and our clinical experience since the early disease is often asymptomatic and late diagnosed.

MATERIALS AND METHODS

From 2010 to 2020, all children diagnosed with parathyroid adenoma at our institution were reviewed. We evaluated clinical, biochemical, and radiological aspects and follow-up characteristics.

RESULTS

Eight subjects (F/M = 6/2) ranged in age from 10 to 17 years. Three were symptomatic. The symptoms and findings were stomachache (n = 3), myalgia (n = 2), weakness (n = 2), pancreatitis (n = 1), constipation (n = 1), nausea (n = 1), bone ache (n = 1), and anorexia (n = 1). Laboratory findings on admission were as follows: the mean calcium was 12.59 ± 1.28 (11.2-15.3) mg/dL and the mean parathyroid hormone was 244.81 ± 173.61 (74.9-645.4) pg/mL. The most common localization was the lower part of the left parathyroid gland. Parathyroid adenoma could not be demonstrated by ultrasonography in 2 patients. Tc-99m-Sestamibi scintigraphy revealed the presence of parathyroid adenoma in only 7 of 8 patients. All underwent parathyroidectomy. In our follow-up, 2 subjects needed reoperation. A molecular analysis of 6 cases could be done. One was MEN1 positive. RET sequence analysis of 2, and Casr, GNA11, and AP2S1 sequence analysis of 3 were normal.

CONCLUSION

Parathyroid adenoma should be considered in children older than the first decade with hypercalcemia. Suspected cases should undergo both ultrasonography and scintigraphy. Early diagnosis prevents the patients from serious complications of hypercalcemia such as nephrocalcinosis, diabetes insipid, and arrhythmia. It is significant to perform surgery in centers experienced in parathyroidectomy to minimize postoperative complications.

Pitfalls in the Diagnosis of Primary Hyperparathyroidism in a Sudanese Adolescent Boy; a case disguised as rickets

BACKGROUND

Juvenile primary hyperparathyroidism (PHPT) is a rare endocrine disease. Its diagnosis might be masked by clinical, biochemical, and radiological features of rickets.

CASE PRESENTATION

A 12-year-old Sudanese boy presented with progressive lower limbs deformity and difficulty in walking for six months. It was associated with fatigability, poor appetite, and generalized bone pain. On examination, he was thin, disproportionately short and pubertal, and had bilateral genu valgum deformity. X-rays showed osteopenia and signs of rickets. Biochemical workup revealed mildly elevated serum calcium, low phosphate, high alkaline phosphatase, and high parathyroid hormone with low 25-hydroxy vitamin D₃. Celiac screening, liver function test and renal profile were normal. Serum calcium rose dramatically after vitamin D therapy. Genetic testing was negative for CYP2R1 and MEN1 genes. Ultrasound neck showed left inferior parathyroid adenoma which was surgically excised. Histopathology confirmed the diagnosis of parathyroid adenoma. Postoperatively, he had hypocalcemia which was treated with calcium and alfacalcidol. Corrective surgery is planned for the genu valgum deformity which markedly improved after parathyroidectomy.

CONCLUSION

Although PHPT is extremely rare in the young population, it should be considered in patients with rickets and elevated serum calcium at baseline or after initiating vitamin D therapy.

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.

Outpatient parathyroidectomy in the pediatric population: An 18-year experience

BACKGROUND

Parathyroidectomy for primary hyperparathyroidism (pHPT) is safely performed in the outpatient setting in the adult population. However, concern that children and adolescents have higher complication rates and are unable to recognize and communicate symptoms of hypocalcemia has limited same-day discharges in the pediatric population.

METHODS

Nineteen patients aged 8-18 years (14.1 ± 0.7) underwent outpatient parathyroidectomy for pHPT by a single high-volume endocrine surgeon from 2002-2020. Patient demographics, disease, operations, and complications were reviewed.

RESULTS

Sixteen of 19 patients were symptomatic with fatigue (62.5%), joint pain (37.5%) and nephrolithiasis (18.7%) most common. Mean preoperative Ca and PTH were 11.7 ± 0.3 mg/dL and 102.3 ± 11.8pg/mL, respectively. Ten of 19 had a single adenoma and 9 had multigland hyperplasia including one MEN1 and one MEN2A patient. We performed 11 four-gland explorations, 8 unilateral parathyroidectomies; including 9 transcervical thymectomies, 1 total thyroidectomy, and 1 bilateral central neck dissection. Mean 6-month postoperative Ca and PTH levels were 9.5 ± 0.3 mg/dL (range 7.3-10.3) and 29±5.0pg/mL (range 6.3-77), respectively. One patient developed permanent hypoparathyroidism and 1 had temporary hypocalcemia. No temporary or permanent hoarseness, unplanned same-day admission, wound complications, or Emergency Department visits occurred.

CONCLUSION

Outpatient parathyroidectomy can be safely and effectively performed in pediatric patients with primary HPT.

LEVEL OF EVIDENCE

Treatment Study, Level III.

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.

Management of primary and renal hyperparathyroidism: guidelines from the German Association of Endocrine Surgeons (CAEK)

BACKGROUND AND AIMS

The purpose of this review is to provide updated recommendations for the surgical management of primary (pHPT) and renal (rHPT) hyperparathyroidism, formulating a new guideline of the German Association of Endocrine Surgeons (CAEK).

METHODS

Evidence-based recommendations for the diagnosis and therapy of pHPT and rHPT were assessed by a multidisciplinary panel using PubMed for a comprehensive literature search together with a structured consensus dialogue (S2k guideline of the Association of the German Scientific Medical Societies, AWMF).

RESULTS

During the last 20 years, a variety of new preoperative localization procedures, such as sestamibi-SPECT, 4D-CT, and various PET/CT procedures, were established for pHPT. High-resolution imaging, together with intraoperative parathyroid hormone (IOPTH) measurement, enabled focused or minimally invasive surgery to become the most favored surgical technique. Patients with pHPT and nonlocalizing imaging have a higher risk of multiglandular disease. Surgical therapy provides very high cure rates, with a clear relation to the surgeon's experience in parathyroid procedures. Reoperative parathyroidectomy, children with pHPT or familial forms, and parathyroid carcinoma are addressed and require special surgical expertise. A multidisciplinary team of experienced nephrologists, transplant, and endocrine surgeons should assess the diagnosis and treatment of renal HPT.

CONCLUSION

Surgery is the only curative treatment for pHPT and should be considered for all patients with pHPT. For rHPT, a more selective approach is required, and parathyroidectomy is indicated only when conservative treatment options fail. In parathyroid carcinoma, the adequacy of local resection influences local disease control.

"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.

Pediatric parathyroid disease

Parathyroid glands are critical for calcium and phosphate homeostasis. Parathyroid disease is relatively rare in the pediatric population, but there are some important pediatric-specific considerations and conditions. This article reviews parathyroid physiology, disorders of hyper- and hypo- function, operative management, and uniquely pediatric diagnoses such as neonatal severe hyperparathyroidism. Advances in preoperative imaging, intra-operative gland identification, and management of post-thyroidectomy hypocalcemia are also presented in detail. This article combines a review of fundamentals with recent advances in care, emphasizing pediatric-specific publications.