CRP and idiopathic interstitial pneumonia: LC-IPF: lung cancer and idiopathic pulmonary fibrosis; IPF: idiopathic pulmonary fibrosis; IHD: ischemic heart disease; FVC: forced vital capacity; FEV1: forced expiratory volume in the first second; TLC: total leucocyte count; DLCO: diffusing capacity of the lungs for carbon monoxide; WBC: white blood cells; CRP: C-reactive protein; PCT: procalcitonin