Chronic urticaria (CU) is a common disease characterized by the development of recurrent itchy blisters and/or angioedema lasting longer than 6 weeks. The evidence-based diagnosis of CU is described in the most recent urticaria guideline. Metabolomics has the potential to offer diagnostic biomarkers for the detection and prognosis of diseases and predict the efficacy and safety of pharmaceutical interventions. Determining the variation in metabolites found in the plasma of CU patients (n = 20) and 20 controls has therefore been the goal of this investigation. Samples were analyzed using liquid chromatography quadrupole time-of-flight mass spectrometry after applying acetonitrile precipitation. For the purpose of identifying and characterizing metabolites, the METLIN database was utilized. According to results, 21 metabolites were found to be significantly (VIP score > 0.7, p < .05 and fold analysis >1.5) altered. Differentiations between each group were successful via both OPLS-DA and ROC analysis. While plasma allantoate, homogentisate, indole acetate, proline, phenylalanine levels decreased in CU patients compared to healthy subjects, tryptophan, spermidine, phenyl pyruvate, oleic acid, lysine, valine, ornithine, histidine, glutamate, leucine, kynurenine, hypoxanthine, tyrosine, glucose, creatine and cortisol levels were significantly increased. Diagnosis of CU could be achieved by evaluating the metabolic profile of patients.
Keywords: Chronic urticaria; LC/Q-TOF/MS/MS; bioinformatics; chemometry; metabolomics.