Brown HJ, Tajudeen BA, Kuhar HN, et al. - Given the strong correlation of atopy with chronic rhinosinusitis (CRS). researchers herein aimed at ascertaining if patients with atopy and CRS can be defined by markers of tissue histopathology, systemic biomarkers, and clinical factors, that may guide their response to new pharmacologic agents. In a retrospective cohort of CRS patients who underwent functional endoscopic sinus surgery (FESS), comparison was performed between aCRS and non-aCRS control patients with respect a structured histopathology report consisting of 12 variables, comorbid conditions, preoperative total serum IgE levels, and preoperative modified Lund-Kennedy (LK) endoscopic and Sinonasal outcome test (SNOT-22) scores. Among 380 enrolled CRS patients, 286 had comorbid atopy (aCRS). Significantly higher preoperative total SNOT-22 scores and symptom-specific SNOT-22 scores were recorded for aCRS patients relative to non-aCRS; this was noted in all domains except psychological dysfunction. Compared with non-aCRS, aCRS patients exhibited: increased tissue eosinophilia, eosinophil aggregates, Charcot Leyden crystals, fibrosis, total serum IgE levels, polyploid disease, and a prevalence of comorbid asthma and Aspirin Exacerbated Respiratory Disease (AERD). Increased tissue eosinophilia was recorded in patients with aCRS relative to non-aCRS patients even after controlling for polypoid disease, asthma, and AERD. After surgery, intranasal corticosteroids are often used to maintain patients. In patients with unresponsive disease to steroids, atopic status may be considered to identify another management therapy. Atopic CRS patients are suggested to be optimal candidates for biologic agents such as Th₂, eosinophil, and/or IgE-targeted therapies, irrespective of polyp and asthmatic status.