Table 1.

Histopathologic lung damage criteria according to modified scoring system [15]

Scor	Edema	Hemorrhage	Leukocyte infiltration	Alveolar septal thickening
0	No edema	No hemorrhage	Less than 10 cells	No thickened alveolar walls
1	Edema in one quadrant	Hemorrhage in one quadrant	At least 10 cells	Thickened walls in one quadrant
2	Edema in two quadrant	Hemorrhage in two quadrant	At least 25 cells	Thickened walls in two quadrant
3	Edema in three quadrant	Hemorrhage in three quadrant	At least 50 cells	Thickened walls in three quadrant
4	Edema in four quadrant	Hemorrhage in four quadrant	Over 75 cells	Thickened walls in four quadrant