Pericarditis can be classified according to the composition of the inflammatory exudate.

This removes debris and inflammatory exudate.

In a secondary phase, endothelial dysfunction causes cells and inflammatory exudate to enter the alveoli.

Conjunctival suffusion is characterized by redness of the conjunctiva that resembles conjunctivitis, but it does not involve inflammatory exudates.

During the active phase, the base of the ulcer shows 4 zones: inflammatory exudate, fibrinoid necrosis, granulation tissue and fibrous tissue.

The fluid can be pulmonary edema, inflammatory exudate, pus, inhaled water, or blood (from bronchial tree or hemorrhage from a pulmonary artery).

Other forms of PLA2 have been isolated from brain, liver, lung, spleen, intestine, macrophages, leukocytes, erythrocytes, inflammatory exudates, chondrocytes, and platelets (Seilhamer et al., 1986) .

The cause of this situation is usually a periapical or periodontal infection of a maxillary posterior tooth, where the inflammatory exudate has eroded through the bone superiorly to drain into the maxillary sinus.