Rapid analysis of plasma paraquat using sodium dithionite as a predictor of outcome in acute paraquat poisoning.
BACKGROUND
Paraquat poisoning can be lethal, and aggressive treatments might have little or no effect on severely poisoned patients. Accordingly, a convenient prognostic test is necessary to guide therapy for acute paraquat poisoning. Sodium dithionite reduces paraquat to a blue radical form in alkaline plasma with a paraquat detection sensitivity of 2.0 mg/L, which is a 100% lethal concentration at 10 to 12 hours postingestion. The prognostic utility of this simple reaction was examined prospectively.


METHODS
Of 233 paraquat-poisoned patients, who were taken to the hospital within 12 hours after ingestion, the plasma samples obtained on arrival were tested using the sodium dithionite reaction. Standard saline containing 2.0 mg/L paraquat was used as the positive control. The test result was interpreted as being positive when the plasma test yielded a blue color darker than that of the positive control. The effects of aggressive treatment, including cyclophosphamide pulse and continuous venovenous hemofiltration, were evaluated retrospectively.


RESULTS
The discharge survival rate was 41.6% (97 of 233). Ninety-seven of 142 patients with negative or equivocal plasma dithionite test survived. However, all 91 patients with positive plasma dithionite test died of multiorgan failure. Cyclophosphamide and/or continuous venovenous hemofiltration could not improve survival.


CONCLUSIONS
In this single-center study, a positive plasma dithionite test was associated with 100% mortality, despite aggressive treatment. In contrast, negative or equivocal tests were associated with a 68% survival rate. It is believed that after further verification, this test can be used to guide therapy and predict the outcomes of patients suffering acute paraquat poisoning.
Koo
Ja-Ryong
JR
From the Department of Internal Medicine, Hallym Kidney Research Institute, College of Medicine, Hallym University, Chuncheon, Korea. jrkoo@hallym.ac.kr
Yoon
Jong-Woo
JW
Han
Sang-Jin
SJ
Choi
Myung-Jin
MJ
Park
In-Il
II
Lee
Young-Ki
YK
Kim
Sung-Gyun
SG
Oh
Ji-Eun
JE
Seo
Jang-Won
JW
Kim
Hyung-Jik
HJ
Noh
Jung-Woo
JW
D000208:Acute Disease; D000328:Adult; D002606:Charcoal / Q000008:administration & dosage / Q000627:therapeutic use; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000627:therapeutic use; D018572:Disease-Free Survival; D004227:Dithionite; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D006440:Hemofiltration; D006464:Hemoperfusion; D006801:Humans; D008297:Male; D008875:Middle Aged; D010269:Paraquat / Q000097:blood* / Q000506:poisoning*; D011041:Poisoning / Q000097:blood / Q000401:mortality / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
D004227:Dithionite; D002606:Charcoal; D003520:Cyclophosphamide; D010269:Paraquat