LUNG TRANSPLANT REJECTION

Classification of rejection

1. Acute rejection: perivascular inflammation
1. Grade 0 – none
2. Grade 1 – minimal: infrequent perivascular infiltrates
3. Grade 2 – mild: frequent perivascular infiltrates
4. Grade 3 – moderate: dense perivascular infiltrates extending into alveolar space
5. Grade 4 – severe: diffuse perivascular, interstitial, and alveolar infiltrates; pneumocyte damage; and parenchymal necrosis, infarction, pr necrotizing vasculitis
2. Airway inflammation: lymphocyctic bronchitis/bronchiolitis – documented with acute rejection
1. Grade 0 – none
2. Grade 1 – minimal
3. Grade 2 – mild
4. Grade 3 – moderate
5. Grade 4 – severe
3. Chronic airway rejection; bronchiolitis obliterans, active or inactive
4. Chronic vascular rejection; accelerated graft vascular sclerosis

Staging of Bronchiolitis Obliterans Syndrome

Stage	Severity	FEV1(%baseline)
0	No symptoms	>80%
1	Mild	66-80%
2	Moderate	51-65%
3	Severe	<51%