Iodine-induced hypothyroidism (IIH) in paediatric patients receiving peritoneal dialysis: Is risk mitigation possible?

Children with kidney failure who receive maintenance peritoneal dialysis (PD) are at increased risk for thyroid dysfunction. A poorly appreciated cause of hypothyroidism related to PD is iodine overload from exposure to iodine-containing cleaning solutions, iodinated contrast agents or povidone-iodine-containing PD caps, particularly in infants and small children. An international survey was conducted to understand current practices regarding iodine exposure in PD patients, the frequency of iodine-induced hypothyroidism (IIH) in patients receiving PD, and to assess awareness of this issue among paediatric nephrologists. Eighty-nine paediatric nephrology centres responded to the survey. Hypothyroidism in PD patients was diagnosed in 64% (n = 57) of responding centres, although only 19 of these centres (33%) suspected or diagnosed IIH. Aetiologies of IIH included exposure to povidone-iodine-containing PD caps (53%), cleaning solutions with iodine (37%) and iodinated contrast (10%). While most centres (58%, n = 52) routinely evaluate thyroid function, only 34% (n = 30) specifically aim to limit iodine exposure. Of centres not routinely evaluating for or utilising methods to prevent iodine exposure and hypothyroidism, 81% reported being unaware of the risk of IIH in PD patients. Hypothyroidism is diagnosed in a substantial percentage of paediatric PD programmes internationally. Increased education on the risk of iodine exposure in children receiving PD may decrease the incidence of IIH as an aetiology of hypothyroidism.