Serum Levels of Eosinophil-derived Neurotoxin in Patients with Chronic Urticaria

BACKGROUND: Despite the many theories that have been published over the years, the exact pathology of chronic urticaria (CU) is still largely unknown. Eosinophils have been implicated in many cutaneous disorders-serving as major effector cells, inducing tissue damage and dysfunction by releasing granule proteins, including eosinophil cationic protein (ECP), inflammatory lipid mediators, mitochondrial DNA, and eosinophil-derived neurotoxin (EDN), which is relatively neutral with some cytotoxic properties. OBJECTIVE: We sought to evaluate serum levels of EDN in patients with CU and to correlate their levels with the severity of their disease. PARTICIPANTS: Fifty patients with CU and 30 matching healthy individuals, serving as controls, were recruited from the outpatient clinic of the Dermatology, Venereology, and Andrology Department of Benha University Hospitals. METHODS: 5ml of venous blood were drawn from all participants in a fasted state, stored in sterile tubes, and used to measure the serum level of EDN following the manufacturer's instructions. RESULTS: The serum level of EDN was statistically significantly different in both groups, and the serum level of EDN significantly correlated with the severity of CU. CONCLUSION: The significantly higher EDN level in patients with CU suggests its role in the pathogenesis of the disease, and its significant positive correlation with the severity of the disease suggests promising therapeutic solutions.