Can rheology be useful in the cystic fibrosis frame

Lung functionality assessment in cystic fibrosis (CF) patients is extremely relevant as most patients succumb to respiratory failure. Inflammatory markers (IMs) and respiratory functional tests, i.e. forced expiratory volume in the first second (FEV1), are used to test pulmonary functions/inflammation and to guide therapy. However, FEV1 has suboptimal reproducibility, and IMs detection is costly. Thus, aim of this work is to use rheology to assess lung functionality/inflammation recurring to the characterization CF patients sputum. Despite some known problems connected with the rheological characterization of inhomogeneous biological fluids, we found that there is a statistical linear correlation among the sputum elastic properties (G’ evaluated at different frequencies) and FEV1, while no correlation exists between the sputum viscous properties (G’’ evaluated at different frequency, and zero shear viscosity) and FEV1. In addition, we found a not linear correlation between sputum elastic properties and the average magnetic relaxation time of water hydrogens entrapped in the sputum. We believe that the potential impact of these rheological findings on health is considerable