Microvascular thrombosis in association with IE sequestration in CM. (A) Coronal section of the brain from a child with fatal CM (right image detail of box in left) shows typical hemorrhagic lesions (arrow). (B) Low-power view (10× lens) shows fibrin deposition in microvessels in formalin-fixed paraffin-embedded tissue from CM case stained for fibrin using trichromic staining (fibrin stains red and red blood cells stain yellow) (C) Detail of box in 1B (40× lens) shows fibrin at the center of a ring hemorrhage (arrow). (D) Colocalization of fibrin and IE cells as indicated by malaria pigment (black dots, arrow). (E) Fibrin deposition was significantly higher in CM cases than in non-CM encephalopathic illness controls. The extent of the vessel lumen containing fibrin was scored as none, <50%, or ≥50 in 10 CM cases and 6 non-CM controls. Scoring was performed by the author and 2 blinded medical pathologists who each scored 50 vessels per case. Datapoints are a combination of the data from all 3 scorers and indicate the percentage of vessels scored at each level in individual cases and bars the mean percentage of vessels scored at each level for the CM or non-CM group as a whole. Micrographs were taken using a Leica DM1L microscope (Leica Microsystems) and a Micropublisher 3.3 RTV (QImaging) camera using Image ProPlus version 6.2 software (Media Cybernetics).