Effectiveness and safety of pamidronate treatment in pediatric patients with osteoporosis

Effectiveness and Safety of Pamidronate Treatment in Pediatric Patients with Osteoporosis Objective: Although it is rare in childhood, osteoporosis is an important disease that can cause skeletal deformities and reduced mobility. Although pamidronate is the most commonly used agent in the treatment of children diagnosed with osteoporosis today, it still does not have FDA approval. In our study, we aimed to investigate the effectiveness and safety of parenteral pamidronate treatment in pediatric patients with osteoporosis followed up in our clinic. Materials and Methods: Twenty-five patients between the ages of 0-18, who were followed up with the diagnosis of osteoporosis in the Pediatric Endocrinology Department of İnönü University Faculty of Medicine between 2000-2019, received at least 6 months of parenteral pamidronate treatment with 3-months intervals, and had sufficient data in medical records were included in our retrospective study. Anthropometric measurements, laboratory findings (serum Ca, P, ALP, 25OHD, PTH), annual number of fractures, activity scores and BMD Z-scores of the patients before treatment and at 6th month, 1st year, 2nd year and 3rd year under treatment were compared. Side effects seen during the treatment were evaluated. All data was obtained from the medical records of the patients. Results: The mean age at diagnosis of patients with osteoporosis was 7.69 ± 5.35 years. Sixty percent (15/25) of the patients were diagnosed with primary osteoporosis, and the others were diagnosed with secondary osteoporosis. Patients with primary osteoporosis were found to have a lower mean age, a higher number of fractures and also higher frequency of deformity at diagnosis. There was no significant difference between the BW SDS, height SDS, BMI SDS and activity scores of the all patients with osteoporosis before pamidronate treatment and during the treatment process. While there was a significant decrease in the number of fractures at the 6th month of the treatment compared to the pre-treatment, it was observed that this difference disappeared in the following years. Laboratory data remained within normal limits during the treatment period. Mean BMD Z-score values of the patients at 6th month, 1st, 2nd and 3rd year during the treatment process were found to be significantly higher than pre-treatment values, and also a significant increase was found over the years. Side effects were observed in 32% of the patients, the most common side effect was asymptomatic hypocalcemia. No serious or life-threatening side effects were observed. Conclusion: Parenteral pamidronate therapy is an effective and safe option to increase the BMD Z-score in childhood osteoporosis. Keywords: Childhood osteoporosis, primary osteoporosis, secondary osteoporosis, osteogenesis imperfecta, pamidronate, BMD Z-score.