Increased IgG4-Positive Plasma Cells in Granulomatosis with Polyangiitis: A Diagnostic Pitfall of IgG4-Related Disease
Figure 1
(a) Increased IgG4-positive cells with a high IgG4+/IgG+ ratio. (b) IgG+ cells from corresponding hotspot (immunohistochemistry, 400x original magnification).
