[Paraquat poisoning. Pulmonary lesions]

The preliminary results of a study of the pulmonary histopathological injuries observed in autopsy samples from six paraquat poisoning cases are presented. The pattern of the pulmonary injuries is discussed with regard to the survival time. Twenty-four hours after the ingestion, intense edema of the alveolar walls, congestion, capillary thrombosis and infiltrations of polynuclears in the septa were observed. Areas of ischemic necrosis were also noticed. Four days after the ingestion the histological changes remained. Six days after it was already observed the formation of hyaline membranes. After nine days the histological patterns changed, with thickness and septal fibrosis and residues of hyaline membranes.