P ulmonary
Aliya N. Husain, M.D.
XII. Lung Transplantation
A. Rejection
  1. Acute rejection is characterized by perivascular and peribronchial infiltration of lymphocytes, plasma cells, eosinophils and occasionally neutrophils. It is graded into minimal, mild, moderate and severe based on the amount of inflammatory infiltrate.
  2. Chronic rejection is a fibrosing process which partially or totally occludes small airways (bronchiolitis obliterans). It is often accompanied by chronic vascular rejection (intimal fibrosis and medial hypertrophy of pulmonary arteries).
B. Opportunistic infectionsThis is most commonly seen in the lung transplant population are CMV pneumonitis and aspergillosis, either of the bronchial anastomotic site or of the lung. Pneumocystis pneumonia is largely preventable due to effective prophylaxis. Candidiasis occurs often at the bronchial anastomosis.
C. Post-transplant lymphoproliferative disorder (PTLD) This occurs in 3-5% of lung transplant recipients. It is composed of pleomorphic lymphocytes with plasma cells and scattered histiocytes. It may be monoclonal or polyclonal.