(RMT) Cells and Inclusions Seen in Synovial Fluid

neutrophil

polymorphonuclear leukocyte

lymphocyte

mononuclear leukocyte

macrophage (monocyte)

large mononuclear leukocyte, maybe vacuolated

synovial lining cell

similar to macrophage, but may be multinucleated resembling a mesothelial cell

LE cell

neutrophil containing characteristic ingested “round body“

reiter cell

vacuolated macrophage with ingested neutrophils

RA cell (ragocyte)

neutrophil with dark cytoplasmic granules containing immune complexes

cartilage cells

large, multinucleated cells

rice bodies

macroscopically resemble polished rice; microscopically show collagen and fibrin

fat droplets

refractile intracellular and extracellular globules; stain in sudan dyes

hemosiderin

inclusions within clusters of synovial cells

hemosiderin

iron content

negative birefringence

parallel

negative birefringence

yellow

positive birefringence

blue

positive birefringence

perpendicular