Incidence of hyperkalemic RTA in pediatric post-renal transplant patients and the role of fludrocortisone.

BACKGROUND: One of the most common forms of post-transplant tubulopathy is hyperkalemic (RTA). The true incidence of hyperkalemic RTA in pediatric patients has not yet been studied. (CNIs) remain mostly blamed. Most cases are managed with sodium bicarbonate and potassium binding resins. Few studies have addressed the role of fludrocortisone in managing such patients. This study aimed to assess the efficacy and safety of fludrocortisone in the treatment of post-transplant hyperkalemic RTA.

METHOD: This is a retrospective cohort study of all pediatric (aged ≤16 years) post-kidney transplant patients who were followed up in KFSH-D, Saudi Arabia from January 2015 until September 2019. A total of 136 pediatric post-renal transplant patients were reviewed, of these, 39 patients who were commenced on fludrocortisone post-transplant treatment and were followed up for at least 6 months after fludrocortisone initiation were included in this study.

RESULTS: The incidence of hyperkalemic RTA in our center was 60.6%. The medication requirements decreased significantly after fludrocortisone initiation. The median sodium bicarbonate dose decreased from 1.2 mEq/kg/day (range, 0.0-4.7) prior to fludrocortisone treatment to 0.0 mEq/kg/day (range, 0.0-4.3) at 6-month follow-up (p < .001). Similarly, the median (SPS) dose decreased from 1.2 g/kg/day (range, 0.0-4.0) before fludrocortisone treatment to 0.0 g/kg/day (range, 0.0-3.6) (p < .001) at 6-month follow-up. The initial mean potassium level 5.17 mmol/L ± 0.61SD dropped to 4.60 mmol/L ± 0.46SD at 6-month follow-up (p < .001). The initial mean serum bicarbonate level 22.31 mmol/L ± 3.67SD increased to 24.5 mmol/L ± 2.8SD at 6-month follow-up (p < .01). No effect on systolic and diastolic blood pressure was observed during follow-up.

CONCLUSION: Hyperkalemic RTA incidence was high in our cohort. Fludrocortisone is safe and effective drug in the treatment of post-kidney transplant hyperkalemic RTA.