LCN2 and medical procedure: Besides its role as a biomarker of acute kidney injury,49 LCN2 was identified as mediator of the innate immune response50 and a protective component during the development of airway hyperreactivity and inflammation in a murine model of allergic airway.34 Moreover, elevated serum levels of LCN2 were found to be associated with improvement in the quality of life of patients with chronic urticaria.51 In light of these studies, our data may indicate a specific role for LCN2 in the IgE-mediate immune response, possibly by acting as a negative feedback in the inflammatory cascade.