Clinical Retrospective Study On Microscopic Polyangiitis Patients With Lung Involvement(Report Of 94 Cases)

Objective To analyze the characteristics of lung involvement in microscopic polyangiitis(MPA)patients and its treatment,and improve the level of awareness and treatment.Methods From Mar.2011 to Oct.2016,94 patients were diagnosed with MPA with lung involvement in The First Affiliated Hospital of Chongqing Medical University.Their clinical data including clinical manifestations,laboratory test results,chest imaging features,pathological features,treatment and prognosis were retrospectively analyzed.The main clinical manifestations,laboratory test results and chest imaging features were compared between patients whose initial symptoms were respiratory symptoms(group A)and patients whose were non-respiratory symptoms(group B).Results The patients included 49 males and 45 females.The mean age was(65.2±10.9)yeas.In MPA patients with lung involvement,main manifestations were cough,expectoration,hemoptysis and dyspnea.21 patients were found with respiratory failure.The characteristics in chest CT/HRCT were divided into three kinds of patterns:(1)Patchy consolidation or ground-glass opacities(64.89%);(2)Reticular or honeycombing(13.83%);(3)Both of these were present(21.28%).12(12.77%)cases had radiographic evidences of usual interstitial pneumonia(UIP),and 30(31.91%)cases had diffuse alveolar hemorrhage(DAH).There were 34 patients in group A and 60 patients in group B.The incidence of respiratory symptoms was more often in group A(P<0.05),including cough/expectoration(32/34 vs.46/60),hemoptysis(15/34 vs.13/60)and dyspnea(27/34 vs.20/60).No significant differences were found between group A and B in constitutional symptoms and other extra-pulmonary manifestation(P>0.05),such as fever(24/34 vs.37/60),rash(3/34 vs.8/60),hematuresis(22/34 vs.41/60),proteinuria(21/34 vs.40/60).The incidence of DAH in chest CT was significantly higher in group A than group B(18/34 vs.12/60,P<0.05).All the patients who accepted treatment were treated with glucocorticoids and immunosuppressive agents.Eleven of severe/life-threatening patients were treated with intravenous pulsed methylprednisolone with cyclophosphamide.Conclusion The prevalence of lung involvement in patients with MPA is high.Pulmonary fibrosis and diffuse alveolar hemorrhage are the special radiological findings.DAH is more likely to occur in patients whose initial symptoms are respiratory symptoms.Glucocorticoids combined with immunosuppressive agents are the main treatment of MPA patients,and the short-term prognosis is relatively well.