Table 2. Scoring system for histology.

	Hemorrhage	Inflammation	Necrosis
0 –None	None/normal	None/normal	None/normal
1 –Trace	Focal, occasional	≤ 20 inflammatory cells per 40x HPF	Architectural changes, picnotic nuclei
2 –Mild	Multifocal and regional	21–100 inflammatory cells per 40x HPF, mild edema	Focal necrosis
3 –Moderate	Regionally diffuse	101–150 inflammatory cells per 40x HPF, moderate edema	Focal necrosis within different tissue structures
4 –Severe	100% RBCs	≥151 inflammatory cells per 40x HPF, extensive edema	Diffuse necrosis

HPF = high powered field