The changing pattern of paraquat poisoning in man.

The clinical and pathological findings are described in 14 patients who died between 6 hours and 26 days after drinking paraquat. Respiratory failure and delayed pulmonary fibrosis have become the hallmark of this poison, but were not the common mode of death in this series. Toxic myocarditis, renal tubular necrosis and centrilobular liver cell damage were significant factors in the eight deaths which occurred within 5 days of paraquat ingestion. Similar abnormalities plus respiratory failure caused the two deaths which occurred 5 and 6 days after consumption of the poison. Respiratory failure was the sole cause of death in only four patients who died 8 to 26 days after drinking paraquat, although the lungs showed pathological changes in all cases. The patients who died in multisystem failure, with one exception, had drunk larger quantities of paraquat than those who survived for a longer period and died in respiratory failure.