Can low field nuclear magnetic resonance be used to monitor lung functionality of cystic fibrosis patients?

The increase of long surviving cystic fibrosis (CF) patients needs great effort for the assessment of lung functionality/inflammation since the majority of them still die of respiratory failure. The commonly used test (forced expiratory volume in the first second (FEV1), evaluation of inflammatory markers such as blood neutrophil counts (BNC) and acute-phase reactants such as C-reactive protein (CRP)) can be complex in their execution (FEV1) or expensive (BNC, CRP). Thus, in consideration of the intense monitoring required in CF patients, more effective, low cost and simple strategies are urgently necessary. As it is well known [1, 2] that the sputum of patients affected by CF or other obstructive pulmonary diseases contain pathological concentrations of proteins, alginates, DNA, bacteria and mucin, it is conceivable that these components can affect the magnetic relaxation of the water hydrogens entrapped in the sputum as it occurs in aqueous polymeric solutions and gels [3]. As the illness severity is connected to the concentration of these components, Low field NMR could represent a profitable tool to evaluate lung functionality/inflammation. Indeed, measuring the average sputum spin-spin relaxation time T2m of both artificial sputum samples (water added by different amounts of the pathological components), and conditional sputum (healthy volunteers saliva, added by different amounts of the pathological components), we found that T2m is greatly affected by the presence of pathological components when their concentration ranges from normal up to pathological concentrations. In addition, we found a good statistical correlation between T2m - FEV1, T2m - CRP and T2m -BNC. Figure 1 shows the decrease of T2m relative to a CF patient in comparison with healthy subjects and patients affected by less severe lung pathological conditions, i.e. asthma and chronic obstructive pulmonary disease (COPD). In conclusion, we can affirm that Low field NMR has the potential to become a valuable, fast and economic monitoring tool for pulmonary diseases in CF patients, as well as in other chronic pulmonary diseases.