Treatment of cystic fibrosis pulmonary exacerbation and serum levels of neuropeptides.

The identification of biomarkers for pulmonary exacerbations in cystic fibrosis (CF) is inevitable. We aimed to evaluate the serum levels of substance p (SP), neuropeptide Y (NPY), and Pituitary Adenylate Cyclase Activating Polypeptide (PACAP), at time of pulmonary exacerbation and after treatment with antibiotics. Twenty cystic fibrosis patients with mean age of 8.83 years (±4.37) were enrolled. Serum samples were taken at the time of admission and two weeks post-antibiotic therapy. Serum levels of target markers were determined using ELISA. Serum SP, NPY, and PACAP levels were significantly higher at exacerbation (229.22 ± 73.86 pg/ml, 1869.89 ± 787.14 pg/ml, and 32,261.51 ± 22283.78 fg/ml, respectively) than post-antibiotic therapy (206.29 ± 77.83 pg/ml, 1412.95 ± 647.09 pg/ml, and 17,359.39 ± 10105.39 fg/ml, respectively; p < 0.05). Positive correlations were observed between serum levels of SP and PACAP (r = 0.515, p = 0.020) and NPY (r = 0.779, p < 0.001), and between NPY and PACAP (r = 0.513, p = 0.021). A negative correlation was found between NPY and BMI z-score (r = -0.503, p = 0.024). As a conclusion, serum SP, NPY and PACAP levels are potential biomarkers for CF pulmonary exacerbations and response to antibiotic therapy.