TABLE 1.

Scoring grid for histopathologic examination of lung tissue

Parameter	Criterion	Score	Interpretation
Collapse-consolidation	Percent replacement of air with fluid and cellular material	0	None
		1	1-10%
		2	11-50%
		3	51-100%
Alveolar hemorrhage	Number of erythrocytes per alveolus	0	None
		1	1-5
		2	6-10
		3	>10
Infiltration	Number of PMN leukocytes per 10 alveolar spaces in areas of consolidation	NA
Alveolar edema	Degree of filling of alveolus with proteinaceous material	0	None
		1	Mild
		2	Moderate
		3	Severe
Bronchial epithelial lesions	Number of bronchi that show necrosis and sloughing of epithelium, epithelial inflammation, and inflammatory exudate within the bronchial space	0	None
		1	1
		2	2
		3	≥3
Pleuritis	Degree of fibrin deposition and entrapped PMN leukocytes on the pleural surface	0	None
		1	Mild
		2	Moderate
		3	Severe