Characteristics of pulmonary function and high-resolution CT imaging in combined pulmonary fibrosis andemphysema

Objective To investigate clinical symptom,sign,pulmonary function parameters and high-resolution CT in patients with combined pulmonary fibrosis and emphysema(CPFE),and analyze the relationship between the pulmonary fibrosis and emphysema severity on high-resolution CT and pulmonary function parameters. Methods A prospective,randomized,controlled study was performed.40 CPFE patients and 80 COPD patients were selected.The common clinical features and pulmonary function parameters were compared between the two groups,and the relation of pulmonary fibrosis and emphysema severity with pulmonary function parameters of CPFE patients was analyzed. Results 40 CPFE cases were(71.8±8.1)years old,33 of them were male,36 of them were smokers,and courses of disease were from six months to 15 years.The main clinical symptoms were cough(34 cases),dyspnea(32 cases),and double lung crackles(23 cases).Compared with the COPD patients,PaO2 in CPFE patients decreased(t= - 2.016,P 0.05).Characteristic radiologic findings in the CPFE included upper-lobe emphysema and lower-lobe interstitial fibrotic changes.The centrilobular emphysema,paraseptal emphysema,panlobuia emphysema,and bullous were present in 87.5%,27.5%,10.0%,and 35.0%, respectively. The reticular opacities,ground-glass opacities,and honeycombing were present in 97.5%,55.0%,and 37.5% of CPFE patients,respectively.Adjusted for gender,age,and smoking confounding factors,pulmonary fibrosis had relation with DL CO% pred(P< 0.01), emphysema severity had relation with DL CO% pred and FEV1/FVC(P< 0.05). Conclusions CPFE occurs mainly in male smokers with lightly damaged pulmonary ventilation function, but significantly decreased diffusing capacity.The diagnosis is based on the presence of both emphysema and pulmonary fibrosis on high-resolution CT.Patients with severe pulmonary fibrosis and emphysema has worse pulmonary diffusion. Key words: Pulmonary fibrosis; Pulmonary emphysema; Respiratory function tests; High reolution CT