Expression and prognostic value of C-reactive protein in adult immune thrombocytopenia (ITP) patients

The aim of this study was to investigate the effect of C-reactive protein (CRP) on the prognosis of adult patients with Immune thrombocytopenia purpura (ITP). A retrospective study of 628 adult ITP patients, as well as 100 healthy and 100 infected patients, attending the Affiliated Hospital of Xuzhou Medical University from January 2017 to June 2022 was performed. The ITP patients were grouped according to their CRP levels, and the differences in clinical characteristics of each group and the influencing factors of efficacy in newly diagnosed ITP patients were analyzed. CRP levels were significantly higher in the ITP and infected groups compared with healthy controls (P < 0.001), and platelet counts were significantly lower in the ITP group (P < 0.001). Between the CRP normal and elevated group, their age, white blood cell count, neutrophil count, lymphocyte count, red blood cell count, hemoglobin, platelet count, complement C3 and C4, PAIgG, bleeding score, proportion of severe ITP, and proportion of refractory ITP were significantly different (P < 0.05). Patients of severe ITP (P < 0.001), refractory ITP (P = 0.002), and with active bleeding (P < 0.001) had significantly higher CRP levels. Patients with no response after treatment had significantly higher CRP levels than those who achieved CR or R (P < 0.001). Platelet counts (r = − 0.261, P < 0.001) in newly diagnosed ITP patients and treatment outcomes (r = − 0.221, P < 0.001) were negatively correlated with CRP levels, and bleeding score was positively correlated with CRP levels (r = 0.207, P < 0.001). Treatment outcome was positively correlated with decrease in CRP levels (r = 0.313, P = 0.027). A multifactorial regression analysis of the influencing factors of treatment outcomes on newly diagnosed patients found that CRP was an independent risk factor of the prognosis (P = 0.011). In conclusion, CRP can help assess the severity and predict the prognosis of ITP patients.