Table 2. Semi-quantitative summary of the distinguishing features, in terms of sites of inflammation and the respective cell types involved, used to classify lymphocytic bronchitis observed in transbronchial biopsies according to the International Society For Heart & Lung Transplantation (ISHLT) consensus document (1).

Variable
Infiltration	B0: none	B1R: low grade	B2R: high grade	BX: ungraded
Cell lineage		LYM, EOS(−)	LYM, EOS(++), NEU(−)	Sampling artifact, infection
Sub-mucosal	−	+	++
Intra-epithelial	−	−	+
Necrosis/exudates	−	−	−/+

All images taken at 100× magnification and supplied courtesy of Institute for Pathology, Hannover Medical School, Hannover, Germany. B1R, Revised 2007 definition of B1; B2R, Revised 2007 definition of B2; LYM, lymphocytes; EOS, eosinoptablehils; NEU, neutrophils.