P333 Thrombocytosis and Iron Deficiency in Inflammatory Bowel Disease Patients: a Mutual Relationship

Background: Thrombocytosis and iron deficiency anemia (IDA) are frequent complications of inflammatory bowel disease (IBD).The aim of this study was to investigate the correlation between IDA and thrombocytosis in IBD patients.Methods: 198 consecutive IBD patients and 102 healthy controls (HC) participated in the study.The parameters investigated were: PLT, MPV, PDW, PCT, HCT, Hb, MCV, RDW, ferritin, soluble transferrin receptor (sTfR), sTfR-F index (sTfR-F = sTfR/log 10 ferritin), vitamin B12, folic acid.Thrombocytosis was defined as an absolute number of PLT >4×10 5 /mL.Disease activity indices (CDAI for CD and SCCAI for UC) as well as CRP were also correlated with the study parameters.Results: The patients demonstrated decreased HCT, Hb, MCV, MPV and ferritin and increased absolute PLT count, RDW, PDW, PCT, sTfR and sTfR-F index compared to HC (p < 0.0001).Twenty-seven patients exhibited thrombocytosis (13.6%).These patients presented with more severe anemia, significantly altered markers of IDA (RDW, sTfR, sTfR-F index increase and MCV, ferritin decrease) and increased inflammatory indices (CRP, CDAI, SCCAI) compared to those without thrombocytosis (p < 0.05).The absolute PLT count of the IBD patients correlated with HCT, Hb, MCV, RDW, Fe, ferritin, sTfR, sTfR-F, CRP, SCCAI and CDAI.All the other PLT-associated parameters (MPV, PDW and PCT) correlated only with Hb and sTfR (Spearman's rho correlation).In the multivariate analysis only Hb, RDW, CRP, ferritin and sTfR-F continued to correlate with the absolute PLT count (p < 0.05).None of the aforementioned was observed in the HC.Moreover, the absolute PLT count was associated with patients' age (r = 0.23, p = 0.001) and body weight (r = 0.23, p = 0.02) as well as with the use of azathioprine (p = 0.02) and 5-aminosalicylic acid (5-ASA, p = 0.04).Both drugs were associated with a decreased absolute PLT count.Conclusions: Absolute PLT count seems to correlate with IDA parameters as well as with disease activity in our cohort of IBD patients.Hemoglobin, RDW, CRP, ferritin and sTFR-F were the strongest predictors of thrombocytosis in these patients.Controlling the inflammation and managing IDA could lead to reversing thrombocytosis in IBD patients.