CD68 and synovitis: Immunophenotypic characterisation of these three histomorphological patterns demonstrates B cells principally in ‘follicular’ synovitis but absent/low in the ‘pauci-immune’ and ‘diffuse’ pathotypes, the latter predominated by CD68+ monocytes.34 In this study, we tried to categorise patients in the ‘follicular’ pattern (N=8) versus the two other patterns combined (N=6) at baseline, but we could not observe any correlation to treatment response (data not shown).