Lymph Node

Question 1

DD for Kikuchi-Fujimoto disease

Answer 1

SLE lymphadenitis (has degenerate nuclear debris - haemotoxylin bodies, and azzopardi phenomenon - vessel wall encrusted by nuclear debris.
HSV associated lymphadenitis - viral inclusions, neutrophils,
Necrotizing granulomas - neutrophils and plasma cells abundant
Cat-scratch - stellate shape necrosis, neutrophils, Warthin-starry stain detect Bartonella henselae

Question 2

Ancillary test for Kikuchi-Fujimoto disease

Answer 2

Predominance of CD3 and CD8 T cells
Histiocytes express MPO, CD68 and lysozyme
Plasmacytoid dendritic cells express CD68, CD123,CD303 are increased
No monoclonal Ig, or TCR rearrangement