The rate of mortality from paraquat poisoning is high and the principal manifestation of toxicosis is pulmonary impairment.
In this study, we measured the concentration of paraquat in the urine, blood, and some organs in 10 patients with acute paraquat poisoning in order to study the relationships of the kinetics in the body to the concentration in the lungs and to the pulmonary impairment.
The concentration of paraquat dichloride in the blood stream rapidly decreased in the first 24 hours. The half life was about 0.5 hour, within 2 hours (case 3) after intoxication, about 1 hour after 5 hours (case 5), about 2 hours after 10 hours (case 6) and after 24 hours (case 6) was prolonged to over 26 hours.
Therefore, it was suggested that half life was subsequently prolonged with the passage of time.
There were indications that renal disturbance appeared in about 5 hours after oral intake.
Accumulations of paraquat were seen in the organs examined. The largest amount within 24 hours after exposure was recognized in the lungs, and the largest amount after 271 hours was seen in the skeletal muscle. The concentration of paraquat in the lungs was higher than the concentration levels in the blood at death in all the cases.
Although excretion of paraquat from the lungs was very slow. it became faster with DHP and HD. However, excretion from the skeletal muscle was slow, Excretion from the other organs excepting the kidney was considered to be constant, being proportional to the blood concentration levels.
The pathologic examination of the lungs found congestive edema in 6 cases, which became severer with the lapse of time. Partial pulmonary fibrosis was recognized only in long-term survival cases.
The cause of irreversible pulmonary impairment was considered to be the effect of the small amount of paraquat remaining in the lungs which exceeds the concentration in the blood.

BACKGROUND/AIMS: Mucosal healing (MH) is a proposed therapeutic goal for patients with ulcerative colitis (UC). Whether MH is the final goal for UC, however, remains under debate. Therefore, to elucidate clinical variables predicting relapse after MH in UC could be useful for establishing further therapeutic strategy. The aim of this study is to evaluate the predictive variables for relapse in UC-patients after achieving MH. METHODS: From April 2010 to February 2015, 298 UC-patients treated at Kitano Hospital were retrospectively analyzed. MH was defined as Mayo endoscopic subscore of 0 or 1. The cumulative relapse free rate after achieving MH was evaluated. Predictive variables for relapse in UC-patients were assessed by Cox regression analysis. RESULTS: Of 298 UC-patients, 88 (29.5%) achieved MH. Of the 88 UC patients who achieved MH, 21 (23.9%) experienced UC-relapse. Based on Kaplan-Meier analysis, the cumulative relapse free rate at 1, 3, and 5 years after achieving MH was 87.9%, 70.2%, and 63.8%, respectively. The cumulative relapse free rate tended to be higher in the Mayo-0 group (76.9%) than in the Mayo-1 group (54.1%) at 5 years, although the difference was not statistically significant (P=0.313). Cox regression analysis indicated that the use of an immunomodulator was a predictive variable for relapse in UC-patients after achieving MH (P=0.035). CONCLUSIONS: Our data demonstrated that the prognosis of UC patients after achieving endoscopic MH could be based on UC refractoriness requiring an immunomodulator.
Colitis, Ulcerative* ; Endoscopy ; Humans ; Kaplan-Meier Estimate ; Prognosis ; Recurrence* ; Retrospective Studies ; Ulcer*