OBJECTIVETo observe the probability of the lung injury and the features of the lung function injury in ulcerative colitis patients, and to preliminarily study the correlation with its severity, and further to analyze the interior-exterior correlation between Fei and Dachang.

METHODSSeventy patients with UC were assigned to the mild group and the moderate-severe group by the severity, 35 cases in each group. Another thirty healthy subjects were recruited as the control group. Relative indices of the lung function in each group were observed and compared.

RESULTSThe lung injury occurred in 67. 14% of the UC patients (47 cases). Forced expiratory volume at 1st s/forced volume capacity (FEV1/FVC), maximal expiratory flow in 75% vital capacity (FEF75), total lung capacity (TLC), diffusion capacity for carbon monoxide of lung (DLCO), and diffusion capacity for carbon monoxide of lung/alveolar ventilation (DLCO/VA) were lower compared with those of the control group, showing statistical significance (P < 0.05). The ratio of residual volume/total lung capacity (RV/TLC) was lower in the mild group than in the moderate-severe group (P < 0.01). The DLCO was higher in the mild group than in the moderate-severe group (P < 0.05).

CONCLUSIONSMost UC patients were complicated with the lung function injury, mainly featured as middle and small airway obstruction and decreasing diffusing capacity. Besides, along with the aggravation of the disease, the decreasing diffusing capacity and increasing RV/TLC occurred. They provided objective reliance for Fei and Dachang interior-exteriorly correlated.