Effect of IV ferric carboxymaltose treatment on platelet counts and serum transferrin levels in CKD patients not on dialysis with iron deficiency: potential implications for thrombogenicity

Anemia and iron deficiency (ID) are common complications in chronic kidney disease (CKD). Beyond their haematological impact, ID has been linked to heightened thrombotic risk, partly through increases in platelet counts and circulating transferrin. We investigated whether correction of ID with intravenous ferric carboxymaltose (FCM) could modify these parameters in CKD patients with mild anemia. This prospective single-centre study included 41 patients with non-dialysis CKD (mean age 74.9 ± 9.5 years, 66% male), mild anemia, and ID. All received IV FCM (mean dose 616.2 ± 163.8 mg) and were analyzed at baseline and after 4 weeks. Hemoglobin (Hb) levels increased non-significantly (10.9 ± 0.4 vs. 11.1 ± 0.4 g/dL, p = NS). In contrast, platelet counts (240 ± 86 × 10⁹/L vs 222 ± 63 × 10⁹/L, <i>p</i> < 0.001) and serum transferrin levels (265 [235-314] vs. 217 [191-237] mg/dL, <i>p</i> < 0.001) declined significantly. Baseline platelet counts and serum transferrin levels were associated with serum ferritin (r = -0.332, <i>p</i> = 0.04 and r = -0.629, <i>p</i> = 0.001, respectively) and TSAT (r = -0.40, <i>p</i> = 0.01 and r = -0.671, <i>p</i> = 0.001, respectively), but not with Hb levels. ID correction with IV FCM was associated with significant reductions in platelet counts and serum transferrin levels. These findings suggest a link between iron repletion and modulation of thrombogenic pathways in a population at high risk of atherothrombotic events, but warrant confirmation in prospective controlled studies.