PurposeTo develop and evaluate the effectiveness/clinical application of an eosinophil cationic protein-myeloperoxidase (ECP-MPO) test paper before and after treatment in patients with allergic rhinitis (AR).Patients and MethodsWe included 40 controls and 106 AR patients who were enrolled in the Allergy Clinic of Renmin Hospital of Wuhan University. Total IgE, specific IgE and skin prick test (SPT) were detected in all participants. AR patients were treated with oral cetirizine hydrochloride for 14 days. The ECP-MPO test paper results, nasal secretion smear and eosinophil counts, rhinoconjunctivitis total nasal symptom score (TNSS), quality of life questionnaire (RQLQ), visual analogue scale (VAS), serum Th1/Th2/Th17 cytokine, and chemokine data were collected pre- and post-treatment. ECP concentrations in nasal secretions were assessed by ELISA. Pearson correlation test and Kappa consistency test were used for statistical analysis.ResultsThe post-treatment colour grade of the ECP-MPO test paper was lower in AR patients than the pre-treatment grade. The chromogenic grade correlated positively with the ECP concentration and the eosinophil count in nasal secretions both before and after treatment. Positive ECP-MPO test paper results were consistent with positive SPT, Der p-IgE and Der f-IgE result (Kappa values, 0.843, 0.810, 0.795, respectively). The pre- and post-treatment chromogenic grades correlated positively with the TNSS (r1=0·691; r2=0·539), RQLQ (r1=0·783; r2=0·625), and VAS (r1=0·703; r2=0·682) scores in AR patients.ConclusionThe ECP-MPO test paper can effectively detect ECP in nasal secretions, and its results are consistent with those from the SPT, Der p-IgE and Der f-IgE result. Its chromogenic grade can reflect the symptom severity and specific cytokine and chemokine levels in AR patients.