Primary hyperparathyroidism in children: patient report and review of the literature

Forestalling Hungry Bone Syndrome after Parathyroidectomy in Patients with Primary and Renal Hyperparathyroidism

Hungry bone syndrome (HBS), severe hypocalcemia following parathyroidectomy (PTX) due to rapid drop of PTH (parathormone) after a previous long term elevated concentration in primary (PHPT) or renal hyperparathyroidism (RHPT), impairs the outcome of underlying parathyroid disease.

OBJECTIVE

overview HBS following PTx according to a dual perspective: pre- and post-operative outcome in PHPT and RHPT. This is a case- and study-based narrative review.

INCLUSION CRITERIA

key research words "hungry bone syndrome" and "parathyroidectomy"; PubMed access; in extenso articles; publication timeline from Inception to April 2023.

EXCLUSION CRITERIA

non-PTx-related HBS; hypoparathyroidism following PTx. We identified 120 original studies covering different levels of statistical evidence. We are not aware of a larger analysis on published cases concerning HBS (N = 14,349). PHPT: 14 studies (N = 1545 patients, maximum 425 participants per study), and 36 case reports (N = 37), a total of 1582 adults, aged between 20 and 72. Pediatric PHPT: 3 studies (N = 232, maximum of 182 participants per study), and 15 case reports (N = 19), a total of 251 patients, aged between 6 and 18. RHPT: 27 studies (N = 12,468 individuals, the largest cohort of 7171) and 25 case reports/series (N = 48), a total of 12,516 persons, aged between 23 and 74. HBS involves an early post-operatory (emergency) phase (EP) followed by a recovery phase (RP). EP is due to severe hypocalcemia with various clinical elements (<8.4 mg/dL) with non-low PTH (to be differentiated from hypoparathyroidism), starting with day 3 (1 to 7) with a 3-day duration (up to 30) requiring prompt intravenous calcium (Ca) intervention and vitamin D (VD) (mostly calcitriol) replacement. Hypophosphatemia and hypomagnesiemia may be found. RP: mildly/asymptomatic hypocalcemia controlled under oral Ca+VD for maximum 12 months (protracted HBS is up to 42 months). RHPT associates a higher risk of developing HBS as compared to PHPT. HBS prevalence varied from 15% to 25% up to 75-92% in RHPT, while in PHPT, mostly one out of five adults, respectively, one out of three children and teenagers might be affected (if any, depending on study). In PHPT, there were four clusters of HBS indicators. The first (mostly important) is represented by pre-operatory biochemistry and hormonal panel, especially, increased PTH and alkaline phosphatase (additional indicators were elevated blood urea nitrogen, and a high serum calcium). The second category is the clinical presentation: an older age for adults (yet, not all authors agree); particular skeleton involvement (level of case reports) such as brown tumors and osteitis fibrosa cystica; insufficient evidence for the patients with osteoporosis or those admitted for a parathyroid crisis. The third category involves parathyroid tumor features (increased weight and diameter; giant, atypical, carcinomas, some ectopic adenomas). The fourth category relates to the intra-operatory and early post-surgery management, meaning an associated thyroid surgery and, maybe, a prolonged PTx time (but this is still an open issue) increases the risk, as opposite to prompt recognition of HBS based on calcium (and PTH) assays and rapid intervention (specific interventional protocols are rather used in RHPT than in PHPT). Two important aspects are not clarified yet: the use of pre-operatory bisphosphonates and the role of 25-hydroxyitamin D assay as pointer of HBS. In RHPT, we mentioned three types of evidence. Firstly, risk factors for HBS with a solid level of statistical evidence: younger age at PTx, pre-operatory elevated bone alkaline phosphatase, and PTH, respectively, normal/low serum calcium. The second group includes active interventional (hospital-based) protocols that either reduce the rate or improve the severity of HBS, in addition to an adequate use of dialysis following PTx. The third category involves data with inconsistent evidence that might be the objective of future studies to a better understanding; for instance, longer pre-surgery dialysis duration, obesity, an elevated pre-operatory calcitonin, prior use of cinalcet, the co-presence of brown tumors, and osteitis fibrosa cystica as seen in PHPT. HBS remains a rare complication following PTx, yet extremely severe and with a certain level of predictability; thus, the importance of being adequately identified and managed. The pre-operatory spectrum of assessments is based on biochemistry and hormonal panel in addition to a specific (mostly severe) clinical presentation while the parathyroid tumor itself might provide useful insights as potential risk factors. Particularly in RHPT, prompt interventional protocols of electrolytes surveillance and replacement, despite not being yet a matter of a unified, HBS-specific guideline, prevent symptomatic hypocalcemia, reduce the hospitalization stay, and the re-admission rates.

Bilateral genu valgum: an unusual presentation of juvenile primary hyperparathyroidism

Primary hyperparathyroidism is a generalized disorder of bone and mineral metabolism caused by autonomous secretion of parathyroid hormone. It is primarily seen in adults with typical age of presentation between third and fifth decades of life. Juvenile hyperparathyroidism is a rare disorder. The common presentations in order of incidence are fatigue and lethargy, headache, nephrolithiasis, nausea, abdominal pain, vomiting and polydipsia. Though skeletal symptoms include bone pains and fractures, but the presence of limb deformity is atypical. We report a case of young girl who presented with isolated progressive genu valgum of both lower limbs and pigeon-shaped chest deformity. She was found to have hypercalcemia and hypophosphatemia with raised parathyroid hormone levels. The neck imaging showed a single adenoma in the left inferior parathyroid gland. The surgical removal of parathyroid adenoma was performed.

Endocrine disorders and the neurologic manifestations

The nervous system and the endocrine system are closely interrelated and both involved intimately in maintaining homeostasis. Endocrine dysfunctions may lead to various neurologic manifestations such as headache, myopathy, and acute encephalopathy including coma. It is important to recognize the neurologic signs and symptoms caused by the endocrine disorders while managing endocrine disorders. This article provides an overview of the neurologic manifestations found in various endocrine disorders that affect pediatric patients. It is valuable to think about 'endocrine disorder' as a cause of the neurologic manifestations. Early diagnosis and treatment of hormonal imbalance can rapidly relieve the neurologic symptoms. Better understanding of the interaction between the endocrine system and the nervous system, combined with the knowledge about the pathophysiology of the neurologic manifestations presented in the endocrine disorders might allow earlier diagnosis and better treatment of the endocrine disorders.

Endocrine check-up in adolescents and indications for referral: A guide for health care providers

The American Academy of Pediatrics recommends that young people between the ages of 11 and 21 years should be seen annually by their pediatricians, since annual checkups can be an important opportunity for health evaluation and anticipatory guidance. Parents of infants and young children are accustomed to regularly visiting a pediatrician for their child's checkups. Unfortunately, when children reach the teen years, these annual checkups may decrease in frequency. In routine check-ups and medical office visits, particular attention should be paid to the possibility of a developmental or endocrine disorder. Early diagnosis and treatment may prevent medical complications in adulthood and foster age-appropriate development. Our purpose is to acquaint readers with the concept, based on current scientific understanding, that some endocrine disorders may be associated with a wide range of deleterious health consequences including an increased risk of hypertension and hyperlipidemia, increased risk of coronary artery disease, type 2 diabetes, significant anxiety and lack of self-esteem. Understanding the milestones and developmental stages of adolescence is essential for pediatricians and all other health providers who care for adolescents. Treating adolescents involves knowledge of a variety of medical, social and legal information; in addition, close working relationships must be established within the adolescent's network to create an effective care system. In summary, we underline the importance of a periodic endocrine checkup in adolescents in order to identify endocrine problems early and develop an approach to treatment for those patients who need help during this time. Indications for endocrine referral for professional and other healthcare providers are also included. These lists are clearly not intended to be comprehensive, but will hopefully serve as a guide for specific clinical circumstances.

Total parathyroidectomy in a large cohort of cases with hyperparathyroidism associated with multiple endocrine neoplasia type 1: experience from a single academic center

Most cases of sporadic primary hyperparathyroidism present disturbances in a single parathyroid gland and the surgery of choice is adenomectomy. Conversely, hyperparathyroidism associated with multiple endocrine neoplasia type 1 (hyperparathyroidism/multiple endocrine neoplasia type 1) is an asynchronic, asymmetrical multiglandular disease and it is surgically approached by either subtotal parathyroidectomy or total parathyroidectomy followed by parathyroid auto-implant to the forearm. In skilful hands, the efficacy of both approaches is similar and both should be complemented by prophylactic thymectomy. In a single academic center, 83 cases of hyperparathyroidism/ multiple endocrine neoplasia type 1 were operated on from 1987 to 2010 and our first surgical choice was total parathyroidectomy followed by parathyroid auto-implant to the non-dominant forearm and, since 1997, associated transcervical thymectomy to prevent thymic carcinoid. Overall, 40% of patients were given calcium replacement (mean intake 1.6 g/day) during the first months after surgery, and this fell to 28% in patients with longer follow-up. These findings indicate that several months may be needed in order to achieve a proper secretion by the parathyroid auto-implant. Hyperparathyroidism recurrence was observed in up to 15% of cases several years after the initial surgery. Thus, long-term follow-up is recommended for such cases. We conclude that, despite a tendency to subtotal parathyroidectomy worldwide, total parathyroidectomy followed by parathyroid auto-implant is a valid surgical option to treat hyperparathyroidism/multiple endocrine neoplasia type 1. Larger comparative systematic studies are needed to define the best surgical approach to hyperparathyroidism/multiple endocrine neoplasia type 1.

Nephrocalcinosis and urolithiasis in children

The incidence of adult urolithiasis has increased significantly in industrialized countries over the past decades. Sound incidence rates are not available for children, nor are they known for nephrocalcinosis, which can appear as a single entity or together with urolithiasis. In contrast to the adult kidney stone patient, where environmental factors are the main cause, genetic and/or metabolic disorders are the main reason for childhood nephrocalcinosis and urolithiasis. While hypercalciuria is considered to be the most frequent risk factor, several other metabolic disorders such as hypocitraturia or hyperoxaluria, as well as a variety of renal tubular diseases, e.g., Dent's disease or renal tubular acidosis, have to be ruled out by urine and/or blood analysis. Associated symptoms such as growth retardation, intestinal absorption, or bone demineralization should be evaluated for diagnostic and therapeutic purposes. Preterm infants are a special risk population with a high incidence of nephrocalcinosis arising from immature kidney, medication, and hypocitraturia. In children, concise evaluation will reveal an underlying pathomechanism in >75% of patients. Early treatment reducing urinary saturation of the soluble by increasing fluid intake and by providing crystallization inhibitors, as well as disease-specific medication, are mandatory to prevent recurrent kidney stones and/or progressive nephrocalcinosis, and consequently deterioration of renal function.

Hypercalcemia in children and adolescents

PURPOSE OF REVIEW

In this review, we define hypercalcemia levels, common causes for hypercalcemia in children, and treatment in order to aid the practicing pediatrician.

RECENT FINDINGS

One rare cause of hypercalcemia in the child is familial hypocalciuric hypercalcemia (also termed familial benign hypercalcemia). Mutations that inactivate the Ca-sensing receptor gene FHH have been described as an autosomal dominant disorder, but recently milder mutations in the CASR have been shown to cause hypercalcemia when homozygous.

SUMMARY

Normal serum levels of calcium are maintained through the interplay of parathyroid, renal, and skeletal factors. In this review, we have distinguished the neonate and infant from the older child and adolescent because the causes and clinical features of hypercalcemia can differ in these two age groups. However, the initial approach to the medical treatment of severe or symptomatic hypercalcemia is to increase the urinary excretion of calcium in both groups. In most cases, hypercalcemia is due to osteoclastic bone resorption, and agents that inhibit or destroy osteoclasts are, therefore, effective treatments. Parathyroid surgery, the conventional treatment for adults with symptomatic primary hyperparathyroidism, is recommended for all children with primary hyperparathyroidism.

Primary hyperparathyroidism in pediatric patients

OBJECTIVE

Primary hyperparathyroidism (HPT) is unusual in children. We reviewed our experience with HPT to better characterize these children.

METHODS

The retrospective review of patients <19 years old who underwent parathyroid resection for primary HPT from 1970 to 2000 was performed at a single institution..

RESULTS

Fifty-two patients were identified. Median age was 16.8 years (range: 4-18.9) with a female-to-male ratio of 3:2. Eighty-five percent had an elevated parathyroid hormone (PTH) level, and 15% had an inappropriately normal PTH level during hypercalcemia. Serum calcium was elevated in all patients except for 2 with multiple endocrine neoplasma (MEN)-IIA and 1 with familial non-MEN HPT, but both had elevated PTH levels. Alkaline phosphatase levels were significantly higher in children with documented bone involvement. At presentation 41 patients (79%) were symptomatic and end-organ damage (nephrocalcinosis, nephrolithiasis, acute pancreatitis, or bone involvement) occurred in 23 patients (44%). Thirty-four patients (65%) had a single adenoma; hyperplasia was identified in 16 patients (27%), and of these cases, 57% occurred in patients diagnosed with MEN-I. Short-term complications included transient hypocalcemia in 29 patients (56%) and transient vocal cord paralysis in 2 patients (4%). Long-term complications were significant for permanent hypocalcemia in 2 patients (4%) and no recurrent laryngeal nerve injuries. No parathyroid abnormalities were identified during exploration in 4 (8%) children. Long-term follow-up was achieved in 98% of patients for a mean and median of 13 years. Resolution of hypercalcemia was achieved in 94% of cases.

CONCLUSION

The diagnosis of primary HPT in pediatric patients is frequently delayed, is commonly symptomatic, and has significant morbidity. For children in whom HPT is suspected, evaluation of serum calcium and PTH levels is diagnostic in 100% of children. Parathyroid resection is effective at restoring normal serum calcium, has few complications, and is the treatment of choice for children with primary hyperparathyroidism.

Carcinoma de paratiróide: características clínicas e anátomo-patológicas de cinco casos

O carcinoma de paratiróide é uma entidade rara, havendo cerca de 535 casos descritos na literatura. Neste trabalho, revisamos a nossa casuística de 5 pacientes com carcinoma de paratiróide avaliados no período de 1983 a 1998 no serviço de Doenças Ósteo-Metabólicas da Universidade Federal de São Paulo, analisando critérios diagnósticos, conduta terapêutica e a evolução destes pacientes e comparando os nossos dados com os achados de literatura. Entre os nossos pacientes, 4 eram do sexo feminino e 1 do sexo masculino, com mediana ao diagnóstico de 52 anos de idade, variando de 10 a 77 anos. As queixas iniciais incluíam presença de dores ósseas acompanhada de perda de peso em 4 pacientes, presença de fratura não traumática em 3 pacientes e traumática em 2 e clínica de nefrolitíase em 1 paciente. Todos apresentavam nódulo palpável em região cervical, níveis de cálcio total bastante elevados com média(±DP) de 14,9±1,7mg/dL. PTH também se encontrava muito elevado, refletindo a magnitude da severidade da doença. Todos foram submetidos à exploração cirúrgica cervical com retirada da massa tumoral, que foi coincidente com o achado palpatório de nódulo cervical. O exame anátomo-patológico revelou o diagnóstico de carcinoma de paratiróide em todos estes casos. No seguimento, 2 pacientes apresentaram recidiva tumoral e evoluíram para óbito por complicações do hiperparatiroidismo. Os outros 3 casos encontram-se em acompanhamento ambulatorial no nosso hospital, sem evidências até o momento de recidiva tumoral.