Endocrine Abstracts

JOINT3452

Introduction: Hypoparathyroidism is a rare endocrine disorder in children which is mainly characterized by insufficiency or inefficiency of parathyroid hormone (PTH) leading to hypocalcemia and hyperphosphatemia. Hypoparathyroidism most commonly results from anterior neck surgery in adults while the most common cause is genetic abnormalities in children. In order to improve the diagnosis and expand the knowledge of the disease, we analyzed relevant data of clinical diagnoses, laboratory findings, molecular determination and long-term follow-up in 24 children with hypoparathyroidism in our center.

Method: A total of 24 patients with hypoparathyroidism, monitored and treated at Department of Pediatric Endocrinology in the SBU Izmir Dr. Behçet Uz Children’s Hospital between 2010 and 2024 years, were retrospectively analyzed for the clinical, laboratory and genetic data. Genetic results of the patients were obtained by Next Generation Sequencing (NGS) or Sanger sequencing methods.

Results: This retrospective study included 24 patients (9 females and 15 males) with hypoparathyroidism. The most common initial presentation was convulsions (33.3%) and muscle spasms in hands (20.8%). Three of the patients were asymptomatic and diagnosed with incidental hypocalcemia. Parents were consanguineous in seven (35%) cases. The mean age of presentation was 6.7±5.9 (1 months-17.3 years). Twenty-three of the patients were followed up with a diagnosis of primary hypoparathyroidism and one patient with a diagnosis of secondary hypoparathyroidism due to thalassemia. Of the patients diagnosed with primary hypoparathyroidism, 12 had syndromic and 11 had isolated hypoparathyroidism. The most common cause of syndromic hypoparathyroidism was Di George syndrome (n:5), followed by GATA3 mutations (n:3); two cases were diagnosed as pseudohypoparathyroidism and one case was diagnosed as Kenny-Caffey syndrome due to a variant in the FAM111A gene. The mean duration of follow-up was 6.9 ± 5.0 years (1.01-17.83). Ten patients had reached their final height at the time of the study and, for whom, long-term outcome data were analyzed. Their mean final height SDS was −1.98 ± 0.46 (Median: −1.85; min: −5.71; max: 0.78). No complications were observed in any of the patients during long-term follow-up.

Conclusions: In this study, clinical and genetic features and long-term follow-up of our patients with hypoparathyroidism were presented. Also, we presented a rare case of Kenny-Caffey syndrome, which presented with hypoparathyroidism. Reporting detailed features of the cases with hypoparathyroidism will increase the knowledge and awareness about the disease.

Keywords: Hypoparathyroidism, DiGeorge Syndrome, GATA3, FAM111A, CASR