Persistent hyperparathyroidism in the 1st year postrenal transplantation

Hyperparathyroidism (HPT) is a frequent complication in chronic kidney disease and may persist in 20%-50% of cases 1 year after kidney transplantation (KT). HPT contributes to long-term allograft dysfunction and increased risk of fractures. There is scant data on the prevalence of HPT in kidney transplant recipients (KTRs) in Saudi Arabia. The aim of this study is to evaluate the prevalence of this complication and to identify its risk factors in a single center in Saudi Arabia.

In a retrospective study, data of 204 KTRs who underwent KT between January 2017 and May 2020 were collected. Data included patient's demographic characteristics, history of hypertension, diabetes mellitus (DM), coronary artery disease, duration of dialysis therapy, dialysis modality, and type of vascular access. Serum intact parathyroid hormone (iPTH) was measured prior to transplant, then every 6 months posttransplant for 2 years.

Two hundred four KTRs were included in our study. The average age was 42.9 ± 15 years. 111 (54.4%) were males, 161 (78.9%) had received living-donor KT, and 43 (21.1%) had deceased donor KT. 83 (40.7%) were diabetic, and 30 (14.7%) had coronary artery disease. Mean serum iPTH was 67.8 ± 54.7 pmol/L before KT, then 30.6 ± 32.7 pmol/L, 24.7 ± 22.3 pmol/L, 21.9 ± 25.2 pmol/L,1-6 months, 6-12 months, and 12-24 months, respectively, post-KT. Forty-seven (23%) patients were found to have persistent HPT (pHPT) at 1-year post-KT, and they showed a higher incidence of DM, longer duration of dialysis, and greater likelihood of receiving deceased donor KT. In multivariate analysis, pre-KT PTH value was an important risk factor of pHPT post-KT. Whereas age, gender, DM, type of transplant, dialysis duration, and serum creatinine were not.

In a single-center experience, (23%) of KTRs had pHPT, and baseline PTH value was an important risk factor in its development.