Pulmonary capillaritis in lung transplant recipients: treatment and effect on allograft function.

The clinical outcomes of lung transplant recipients presenting with post-transplant pulmonary capillaritis have not been well described. We retrospectively reviewed 40 cases of biopsy-proven pulmonary capillaritis in lung transplant recipients. Patients presented with a clinical syndrome characterized by dyspnea, hypoxemia, abnormal chest X-ray, and a decrease in forced expiratory volume in 1 second (FEV1); 25% presented with hemoptysis, and 18% with fulminant respiratory failure. Therapy with intravenous corticosteroids resulted in clinical improvement in 17 cases (43%). A response to plasmapheresis was seen in 12 (67%) of 18 cases refractory to corticosteroids. There were 5 deaths within 3 months of diagnosis. Nine (82%) of 11 lung transplant recipients who presented with capillaritis within 4 weeks post-transplant were alive at 1 year; all but 1 patient achieved expected percent predicted FEV1 values. Only 3 (14%) of 21 who presented with capillaritis > 1 month after transplant had a >20% decrease in the FEV1 after 12 months. These results suggest that post-transplant pulmonary capillaritis is (1) likely a form of acute allograft rejection clinically and histologically distinct from typical acute rejection, (2) less responsive to corticosteroid therapy than typical acute rejection, and (3) not associated with long-term adverse effects on allograft function.