Clinical characteristics of 15 cases of microscopic polyangiitis associated with alveolar hemorrhage

Abstract

To investigate the clinical features of patients with microscopic polyangiitis (MPA) and alveolar hemorrhage (AH), so as to raise the physicians' understanding of this condition. The clinical data of 15 MPA patients combined with AH, who were hospitalized in Peking Union Medical College Hospital from January 2008 to January 2014, were retrospectively analyzed. These 15 subjects accounted for 18.1% of all MPA patients, including 4 males and 11 females with mean age of (59.4 ± 17.9) years old and mean disease duration of 7.5 (1-48) months. Hemoptysis or bloody sputum (14/15) and dyspnea (11/15) were predominant pulmonary manifestations. Hypoxemia appeared in 6 patients (40.0%). An average 8-46 (22.7 ± 4.4) g/L drop of hemoglobin level was seen in all 15 patients. Imaging revealed new bilateral infiltrations or opacities in 13 cases, and bloody bronchoalveolar lavage fluid were found in 6 cases. Compared with MPA patients without AH, the incidence of myalgia [2/15 vs 50.0%(34/68); P=0.009, OR=0.154] and hemoglobin level [(83.2 ± 21.0) g/L vs (102.5 ± 18.7) g/L; P=0.001] were statistically lower in MPA patients with AH. There were no statistical differences in age, sex, interstitial lung disease, renal involvement, peripheral neuropathy and the five factor score between two groups. The proportion of patients who received corticosteroid pulse treatment in MPA with AH group was significantly higher than that of MPA patients without AH [9/15 vs 19.1%(13/68); P=0.003, OR=6.346]. After treatment, 13 cases achieved remission, while 2 died. As an important pulmonary manifestation of MPA, AH could be insidious but fatal. The treatment with steroid, cyclophosphamide and plasma exchange could improve the prognosis.