Linfopenia y pobre respuesta a la eritropoyetina en pacientes en hemodiálisis

Introduction. Erythropoiesis is a complex process that requires the interactions of several factors. The interactions between erythroid precursors and other cells, particularly T lymphocytes, may modulate erythropoiesis. The responsiveness to recombinant human erythropoietin (rHu-EPO) in hemodialysis (HD) patients with lymphopenia remains undetermined. We investigated whether lymphopenia plays a role in the response to rHu-EPO therapy in HD patients. Patients and methods. The study included 126 HD patients on rHuEPO treatment for more than six months. We divided the population in two groups according to the lymphocyte count: group A (n = 75), > 1,200 cells/μL, and group B (n = 51), < 1,200 cells/μL. Results. In patients of groups A and B, the rHuEPO dose (U/kg/week) was 108.5 ± 62.9 versus 136.5 ± 71.4 (p = 0.022); hemoglobin (g/dL) 11.2 ± 1.5 versus 11.1 ± 1.5 (p = 0.6147); age (years) 62.8 ± 15.6 versus 67.5 ± 12.2 (p = 0.0702), and intact parathyroid hormone (iPTH) (pg/mL) 330.3 ± 285.6 versus 514.7 ± 565.0 (p = 0.019). Furthermore, in 60 HD patients on rHu-EPO and calcitriol synergistic therapy, age and iPTH correlated negatively with lymphocyte count (r = –0.379, p = 0.0028; r = –0.309, p = 0.0184), whereas the hemoglobin correlated positively with lymphocyte count (r = 0.277, p = 0.0321). Conclusions. These data suggest that elevated levels of iPTH and age affect the lymphocyte count and that lymphocytes may immunomodulate erythropoiesis. One hypothesis is that older HD patients with severe-moderate secondary hyperparathyroidism showing lymphopenia may have resistance to rHu-EPO, probably mediated via lymphopenia.