Association Between Serum Cortisol Levels and Bacterial Profile in Adults with Chronic Rhinosinusitis

Background: Chronic rhinosinusitis is characterized by long-lasting inflammation, microbial colonization and immune-endocrine interactions, cortisol may regulate bacterial persistence and disease progression. Aims of the study: The aim of the study is to examine the relationship between serum cortisol levels and bacterial profile in adults with chronic rhinosinusitis and assess their clinical importance. Methodology: The study was carried out in March 10, 2025, to February 2, 2026, in Iraq in ENT clinics and laboratories. One hundred participants were involved (70 CRS patients and 30 controls). Clinical and radiological diagnosis was made. Serum cortisol was measured in the blood samples using Cobas e411 analyzer. Standard media was used to culture nasal swabs, and biochemical test was used to identify bacteria. The Kirby-Bauer method was used to determine the antibiotic susceptibility as per the CLSI guidelines. Result: The comparative analysis revealed that there were no significant differences in age (p = 0.38), gender (p = 0.94), and smoking (p = 0.33), and BMI was greater among patients (p = 0.021). There was a significant increase in nasal obstruction and purulent discharge (p < 0.001). The level of cortisol was increased in patients (p < 0.001), and higher levels (p = 0.006). Staphylococcus aureus predominated. There was increased sensitivity to ciprofloxacin and imipenem. Bacterial load was positively correlated with cortisol (p < 0.001). Conclusions: There is an increase in cortisol and the presence of more bacteria colonization that is linked with the chronic rhinosinusitis, probably because of the immunosuppressive effects of stress on the mucosa. This promotes ongoing infection, and endocrine-immune interactions in the development of disease and the need to focus on combined therapies to address the inflammation burden and the microbial burden.