Hypomagnesemia and Calcineurin Inhibitors in Kidney Transplant Recipients

Aim: Post-transplant hypomagnesemia is a frequently encountered and significant electrolyte disorder and is more common in patients using calcineurin inhibitors (CNIs). This study aimed to evaluate the frequency of hypomagnesemia and accompanying conditions in the outpatient follow-up of renal transplant recipients. Methods: This cross-sectional study included 236 renal transplant patients. Demographic characteristics of the patients and their biochemical values, including drug levels, were recorded. Results: Of the patients, 69 (29.2%) were female, and 194 (82.3%) were living donor recipients. The mean age of the entire group was 43.1 years. The frequency of hypomagnesemia was 40% (10/25) in the first 12 months, 26.1% (23/88) between the 12th and 60th months, 26% (32/123) after 60 months, and 27.5% (65/236) in all patients. In patients with higher levels of tacrolimus compared to those with the target level, the frequency of hypomagnesemia increased in those with a posttransplant period of 12-60 months (40.9% vs. 20.8%, p: 0.018) and over 60 months (44% vs. 26%, p: 0.046). In addition, the magnesium (Mg+2) level was lower in patients using tacrolimus compared to those using cyclosporine (CsA) (1.80±0.18 vs 1.91±0.25, p: 0.003). The effect of hypomagnesemia on graft functions was statistically insignificant in all groups. Conclusion: Hypomagnesemia is a common electrolyte disorder in the early and late periods after transplantation. In our study, hypomagnesemia did not differ according to proton pump inhibitor (PPI) use, gender, fasting blood glucose, and glomerular filtration rate. However, the frequency increased in patients using tacrolimus and those with above-target serum tacrolimus levels.