Intravenous immunoglobulin G (IVIg) is used as a replacement therapy in primary immunodeficiency disorders (PIDs). Although IVIg is generally accepted as a safe treatment, the incidence of adverse events (AEs), most of which are mild and transient, varies between 1 % and 81 %. The aim of this study was to determine the adverse effects and influencing factors associated with IVIg replacement therapy in pediatric patients with PID.

Children with PID who received IVIg replacement therapy between January 1, 2012 and December 31, 2021, at Dr. Sami Ulus Children's Hospital were included in our study.

Overall, 69 (52 male, 17 female) patients who received a total of 2,025 IVIg infusions were evaluated. AEs were observed in 40.6 % of the patients and in 8.9 % of the infusions. All AEs encountered in the study were mild to moderate. Immediate-onset AEs were observed in 3.5 % of the infusions and delayed-onset AEs in 5.4 %. Late-onset AEs were not observed. The most commonly observed AEs were headache (n = 50, 2.5 %), fever (n = 37, 1.8 %), and malaise (n = 19, 0.9 %). The most common immediate AE was fever (n = 28, 1.4 %), while the most common delayed AE was headache (n = 44, 2.2 %).

AEs encountered in patients with PID receiving IVIg infusions are mild to moderate. Pediatric patients should be followed up for delayed AEs by contacting their families after the infusion is completed and should be questioned before the next infusion. IVIg replacement is a safe treatment when given with an appropriate premedication and infusion rate.