ESPE Abstracts

Introduction: Bone metabolism disorders in the pediatric age are crucial areas of research, particularly in tertiary care settings where comprehensive evaluation and treatment are paramount.

Aim: To assess the prevalence of bone metabolism disorders among pediatric patients admitted to the Endocrinology Department and to evaluate the medication prescribed for these conditions underlining the current practices and challenges in managing these complex disorders.

Methods: This retrospective record-based study was conducted in a tertiary pediatric hospital in Timișoara, România for 18 months. Among the 679 patients admitted and biologically evaluated (serum and urine calcium, magnesium and phosphorus, PTH level, 25-hydroxy vitamin D, and 1,25-dihydroxyvitamin D) in the Endocrine Department, 339 patients (49.92%) exhibited abnormal values of phospho-calcic metabolism. Genetic tests were performed in selected cases and data on age, gender, clinical manifestations, and medication prescribed were collected with duplicates excluded.

Results: The mean age of the studied patients was 9.8±1.7 years, while boys were predominant (62.83%). The majority were diagnosed with secondary hypoparathyroidism due to hypovitaminosis D (92.92%) and florid rickets (4.42%), while osteogenesis imperfecta was identified in four patients (1.17%). Disorders clinically and biologically diagnosed were genetically confirmed in five patients, including autoimmune polyendocrinopathy syndrome type 1 consisting of primary hypoparathyroidism and chronic mucocutaneous candidiasis (mutations p.ARG15Hisfs*5a and p.R257X (c.769C>T) in heterozygotes status-2 brothers and mutation p.R257X (c.769C>T) in homozygous status in the AIRE gene, respectively), idiopathic infantile hypercalcemia (heterozygous mutations in SLC34A1 and CYP24A1 genes) and X-linked hypophosphatemic rickets (novel PHEX gene mutation). The prescribed treatment was individualized, with cholecalciferol and oral calcium for the majority, and 1-alpha-hydroxy-vitamin D was associated with those with primary hypoparathyroidism. Vitamin D supplementation was restricted in idiopathic infantile hypercalcemia and human monoclonal IgG antibody against neutralized FGF23 was prescribed in the case with X-linked hypophosphatemic rickets after poor response to the conventional therapy (oral phosphorus and active form of vitamin D) according to our national protocol.

Conclusion: Our study points out the significant burden of bone metabolism disorders among pediatric patients, with nearly half presenting abnormal phospho-calcic metabolism values. Secondary hypoparathyroidism due to hypovitaminosis D emerged as the predominant diagnosis, emphasizing the importance of vitamin D prophylaxis in pediatric age. The individualized treatment approach tailored to each patient's condition reflects the complexity of managing these disorders.