Tissue | 0 | 1 | 2 | 3 |
---|---|---|---|---|
Alveolar hemorrhage | None | At least 5 rbcs/alveolus in 1–5 alveoli | At least 5 rbcs/alveolus in 5–10 alveoli | At least 5 rbcs/alveolus in > 10 alveoli |
Alveolar infiltration | No infiltration | < 5 intra-alveolar cells/field | 10–20 intra-alveolar cells/field | > 20 intra-alveolar cells/field |
Intra-alveolar fibrin | None | Fibrin in < 1/3 | Fibrin in 1/3–2/3 | Fibrin in > 2/3 |
Alveolar septae | All thin and delicate | Congested in < 1/3 | Congested in 1/3–2/3 | Congested in > 2/3 |