Pathology of lung transplantation.

The pathology of lung transplantation has many features in common with other solid organ grafts. Acute pulmonary rejection is characterized by perivascular, peribronchiolar, and interstitial mononuclear infiltrates. Chronic rejection causes obliterative bronchiolitis and vascular sclerosis. The transplanted lung is uniquely susceptible to infections, both usual and opportunistic, and these can be difficult to differentiate from rejection. Infection in the foreign graft can produce unusual histological appearances. Posttransplant lymphoproliferative disease can affect the lung allograft primarily. Transbronchial lung biopsy and bronchoalveolar lavage are considered essential to the postoperative management of lung transplants and to the understanding of the pathological processes limiting graft survival.