Table 2.

Granuloma category descriptions. Modified from Rayner et al. (10).

Granuloma category	Organised or unorganised	Necrotic or non-necrotic	Description
1	Unorganised	Non-necrotic	Small, diffuse foci consisting of macrophages, lymphocytes, scattered neutrophils, and eosinophils that lack clearly defined boundaries.
2	Unorganised	Non-necrotic	Similar inflammatory cell types as category 1 lesions but are larger and are more defined.
3	Unorganised	Necrotic	Lesions similar to category 2 but with the addition of focal necrosis, defined by pyknosis and karyorrhexis with the loss of cellular architecture.
4	Organised	Non-necrotic	Well circumscribed, organised lesions which consist primarily of macrophages admixed with neutrophils and other leucocytes with evidence of few peripheral lymphocytes.
5	Organised	Necrotic	Lesions similar to category 4 lesions with the addition of a necrotic foci with degenerate neutrophils.
6	Organised	Necrotic	Classical, largely well-demarcated lesion with central, caseous necrosis and a variable rim of lymphocytes.

Unorganised = lacking peripheral lymphocyte cuff; organised = peripheral lymphocyte cuff present.