Elevated Monocyte Count and Loss of Renal Function in Renal Transplant Patients

Rejection is an important factor affecting graft function in renal transplant patients. Development of acute rejection even after induction treatment suggests that humoral and cellular immune systems are not the only mechanisms responsible for this event. The innate immune system can play roles in rejection. The aim of this study is to evaluate the association between renal function and some absolute values and ratios of various hematologic parameters assessed before and after renal transplantation.

This study included 63 renal transplant patients. Demographic features and laboratory findings were reviewed retrospectively and recorded. For cadaveric and spousal transplantations, induction treatment used antithymocyte globulin (ATG) (group 1 [G1]), and CD25 inhibitor was used for the others (group 2 [G2]). G2 was divided into 2 subgroups based on the estimated glomerular filtration rate (eGFR) decline rate: ≤ 3.5 mL/min/y as group 2a (G2a) and > 3.5 mL/min/y as group 2b (G2b). Hematologic parameters were compared across the groups.

Compared to G1, G2 had higher mean blood pressure, blood urea nitrogen, creatinine, and first month post-transplant lymphocyte and monocyte counts (P = .034, P = .040, P = .003, P = .027, and P = .027, respectively). G2a had higher levels of first-month post-transplant white blood cell, monocyte, and neutrophil counts compared to G2b (P = .018, P = .038, and P = .011, respectively). Receiver operating characteristic analysis of the parameters in G2b showed that a monocyte count of > 750 mm³ was associated with the decline in eGFR.

Elevated monocyte count in patients who had faster eGFR decline and did not receive induction treatment with ATG points to the significance of the innate immune system.