Histologic Grade of Acute Rejection in a Lung Transplant from the 1995 International Society of Heart and Lung Transplantation

reported histologic features of acute lung transplant rejection. This is based primarily on the level of mononuclear infiltrate about blood vessels in the transplant.

 

Parameters:

(1) perivascular (perivenular and periarteriolar) mononuclear infiltrate

(2) extension of the mononuclear infiltrate into the adjacent alveolar septae

(3) mononuclear infiltrate about the bronchi and bronchioles

 

Perivascular Infiltrate	Extension into Alveolar Septae	Grade
none	none	A0
few and scattered	none to few scattered	A1
moderate	none to few scattered	A2
dense	limited extension into	A3
diffuse	diffuse extension into	A4

 

where:

• The presence of a moderate to dense infiltrate in the alveolar septae without a significant perivascular infiltrate may indicate some other process (viral pneumonia, etc.)

• A neutrophilic infiltrate suggests the presence of another or an additional process.

 

A mononuclear infiltrate about the bronchi or bronchioles was listed as absent or present.