[Clinical polymorphism of primary hyperparathyroidism in children]

Primary hyperparathyroidism (PHPT) in children is quite rare, with a prevalence of 2-5 cases per 100,000 children. Hypercalcemia in PHPT has a negative impact on the gastrointestinal tract, urinary, musculoskeletal and nervous systems. Timely diagnosis of the disease in children is difficult due to its rare occurrence and variety of clinical symptoms.

To study clinical manifestations of primary hyperparathyroidism in children depending on the degree of hypercalcemia.

Retrospective observational study with a prospective component 50 patients with primary hyperparathyroidism. All patients underwent a comprehensive laboratory and instrumental study at the Institute of Pediatric Endocrinology, Endocrinology Research Center of Russia in the period 2014-2023.

The clinical manifestations of primary hyperparathyroidism in children are very diverse. Weakness and fatigue were observed in 36% of patients (CI (23; 51)). Frequent manifestations of the gastrointestinal tract were nausea - in 20% (CI (10; 34)), gastritis - in 38%, (CI (25; 53)), duodenogastric reflux - in 24%, CI (13; 38). Hypercalciuria was detected in 64% of patients (CI (49; 77)), urolithiasis - in 36% (CI (23; 51). Complaints of leg pain were observed in 24% of patients (CI (13; 38)) deformity of the lower extremities was present in 20% (CI (10; 34)). 16% of patients had a history of low-traumatic fractures (CI (7; 29)). The median age of onset of the first clinical symptoms of PHPT in children was 13.7 years [10.6; 15.2]. At the time of diagnosis of the disease, 12 patients (24%) had no complaints and were examined due to incidentally detected hypercalcemia (n=3), hypercalciuria (n=1), and detected formations of the parathyroid gland according to ultrasound (n=5), with a family history of multiple endocrine neoplasia syndrome type 1 (n=3). To identify the relationship between the clinical manifestations of PHPT and blood calcium levels, all patients were divided into 3 groups depending on the level of hypercalcemia: mild hypercalcemia - 29 patients, moderate - 16, severe - 5. According to the results of the study, a statistically significant relationship between the presence of individual clinical manifestations of PHPT and the degree of hypercalcemia was not identified, however, a statistical tendency was noted between the presence of individual symptoms of the disease (hypercalciuria, weight loss, vomiting, pain in abdomen, constipation, esophagitis, rib pain, gait disturbance) and blood calcium levels, and a positive association was found between hypercalciuria and hypercalcemia. In addition, it was noted that in patients with severe hypercalcemia, the number of clinical signs is significantly higher than in patients with mild or moderate hypercalcemia.

The study demonstrates the variety of clinical manifestations of PHPT, for which doctors of various specialties - pediatricians, gastroenterologists, nephrologists, neurologists, orthopedic traumatologists, can observe children. In the presence of symptoms and diseases such as fatigue, nausea, pain in the legs, deformation of the lower extremities, low-traumatic fractures, urolithiasis, gastritis, it is necessary to examine the level of calcium in the blood in children.