The Utility of Serum IL-1β and CRP Together with Fractional Exhaled Nitric Oxide in the Diagnosis of Asthma in Adults

Background: Bronchial asthma (BrA), recognized lately as an umbrella, covers various subtypes rather than only one disease. Asthma is a chronic inflammation of the airways, in which cytokines could play a crucial role in its pathogenesis. Hence, labors to progress noninvasive markers for asthma had centered through this era. Presently, the fractional exhaled nitric oxide (FeNO), serum C-reactive protein (CRP), and interleukin levels are emerging analytical biomarkers in this field. FeNO is a noninvasive and practical tool even in mild asthma. This study aimed to evaluate the utility of serum IL-1β and CRP together with fractional exhaled nitric oxide in the diagnosis of adult bronchial asthma. Method: The study was a case control, including 150-patients and 100-healthy controls. FeNO tests, measurements of plasma levels IL-1β and HS-CRP had undertaken for all the participants. The statistical data had examined by SPSS (V/27) for Windows. Descriptive data of the variables had compatibly used. A significance lower than or identical to 0.05 had intended. ROC curve examination of FeNO tests, IL-1β, and HS-CRP, to predict asthma from healthy control had applied. Results: there was a significant difference in the FeNo test, HS-CRP levels, and BMI, while no significant difference in all other variables between the groups. The FeNo results correlate positively, though not significantly, with the levels of IL-1β in asthmatic patients (> 0.05). There was a nonsignificant negative correlation between the FeNo results with the level of HSCRP. The accuracy, sensitivity, and specificity of the IL-1β to distinguish asthma were 68.6% and 58% at 95% CI [0.41-0.745], respectively, which was not significant (p>0.05). However, ROC analysis of HS-CRP revealed predictability for asthma patients (p-0.000), with higher accuracy, sensitivity, and specificity: 89.9%, and 68.1% at 95% CI [0.820-0.979], respectively. The FeNo tests revealed highly significant (0.000), high sensitivity, and specific (91% for both) with high 95% CI [0.938-1.000] predictability for asthma. Conclusion: The utility of circulating HS-CRP is more valuable than IL-1β when combined with fractional exhaled nitric oxide in the diagnosis of asthma. Novel biomarkers could improve the precision of this field.