Urine Paraquat Concentration Research Articles

Clinical research of the differences between hematocrit and serum albumin for evaluating the severity of acute paraquat poisoning

To investigate the clinical values of the differences between hematocrit and serum albumin (HCT-ALB) for evaluating the severity of patients with acute paraquat (PQ) poisoning. Patients with acute PQ poisoning admitted to the Second People's Hospital of Yunnan Province from January 2018 to December 2019 were enrolled, and healthy voluteers during the same period were selected as the control. The general information, poisoning dose and poisoning time of patients, as well as the HCT and serum ALB levels before blood product infusion, intravenous infusion, or hemopurification at admission were collected, and the HCT-ALB was calculated. According to the results of rapid semiquantitative test of PQ in urine at admission, the patients were divided into PQ low concentration group (0-10 mg/L) and PQ high concentration group (30-100 mg/L). The relationship between poisoning time, poisoning dose, HCT-ALB and the degree of acute PQ poisoning were analyzed, and Spearman method was used to analyze the grade correlation. A total of 295 patients with acute PQ poisoning were enrolled, including 118 cases in PQ low concentration group and 177 cases in PQ high concentration group, and another 200 healthy persons matched with PQ patients in gender and age (healthy control group). The poisoning time of PQ low concentration group was significantly longer than that of PQ high concentration group [hours: 11.0 (6.0, 60.0) vs. 8.0 (5.0, 20.5), P < 0.01], but the poisoning dose was significantly lower than that of PQ high concentration group [mL: 10.0 (5.8, 15.0) vs. 40.0 (20.0, 80.0), P < 0.01]. The HCT and HCT-ALB in PQ low and high concentration groups were significantly higher than those of the healthy control group [HCT: (43.14±4.41)%, (43.54±5.40)% vs. (42.14±2.15)%, HCT-ALB: 3.59±6.26, 5.94±7.80 vs. -7.26±3.55, all P < 0.01], but ALB was significantly lower than that of the healthy control group (g/L: 39.54±5.74, 37.60±7.15 vs. 49.40±3.41, both P < 0.01). With the increase of urine PQ concentration, the HCT and HCT-ALB further increased, and ALB further decreased. There were significant differences between PQ high concentration group and PQ low concentration group [HCT: (43.54±5.40)% vs. (43.14±4.41)%, HCT-ALB: 5.94±7.80 vs. 3.59±6.26, ALB (g/L): 37.60±7.15 vs. 39.54±5.74, all P < 0.05]. The poisoning severity of patients with acute PQ poisoning were negatively correlated with poisoning time and ALB (r values were -0.195 and -0.695, respectively, both P < 0.01), there were positively correlated with poisoning dose, HCT, and HCT-ALB (r values were 0.650, 0.256, 0.737, respectively, all P < 0.01), and the correlation between HCT-ALB and poisoning severity was the strongest. The HCT-ALB can reflect the poisoning severity of patients with acute PQ poisoning and indirectly reveal the pathological changes of microvessels in patients with acute PQ poisoning.

A Paper-Based Analytical Device for Analysis of Paraquat in Urine and Its Validation with Optical-Based Approaches.

Paraquat is a highly toxic herbicide. Paraquat poisoning is often fatal and is an important public health threat in many places. The quick identification and timely initiation of treatment based on timely analysis of the paraquat concentration in urine/serum could improve the prognosis for patients. However, current paraquat concentration measurements are time-consuming and difficult to implement due to the expensive and bulky equipment required. To address these practical challenges, paper-based devices have emerged as alternative diagnostic tools for improving point-of-care testing. In this study, we demonstrate the successful use of a paper-based analytical device for the accurate detection of urine paraquat concentration. The developed paper-based analytical device employs colorimetric paraquat concentration measurements. The R2 value for the urine paraquat standard curve was 0.9989, with a dynamic range of 0–100 ppm. The limit of detection was 3.01 ppm. Two other optical-based approaches, Spectrochip and NanoDrop, were used for comparison. The results suggest that the developed paper-based analytical device is comparable to other colorimetric measurements, as determined by Bland–Altman analysis. The device was clinically validated using urine from six paraquat-poisoned patients. The results prove that the developed paper-based analytical device is accurate, easy-to-use, and efficient for urine paraquat concentration measurement, and may enable physicians to improve clinical management.

A retrospective analysis reveals a predictor of survival for the patient with paraquat intoxication

Feasible and accurate predictors are urgently needed to evaluate the survival for patients with paraquat poisoning since the high mortality of paraquat poisoning always resulted in the loss of both life and money. Multiple predictors have been developed to predict prognosis of the patients with PQ poisoning, which however heavily depend on the time of admission to hospitals. Here we reported a feasible and accurate prognosis predictor for patients with paraquat poisoning that is independent of the time of admission to hospitals. Patients with paraquat poisoning were enrolled in this study according to the inclusion and exclusion criteria, which were grouped into survivors and non-survivors based on the 90-days follow-up investigation. The concentration of paraquat in serum and urine, and the baseline clinical parameters associated with the injuries of the liver, kidney, and lung were evaluated to predict the survival of these patients by using receiver operating characteristic curve (ROC) analysis, univariate and multivariate cox regression analyses. A total of 114 patients was included in this study with a survival rate of 54.4%. The median survival days of non-survivors were 6.0 (95%Cl: 4.0–7.8). A new predictor, namely paraquat concentration-associated multiorgan injury index (PCAMII), was established by integrating serum and urine paraquat concentration, serum creatinine, alanine aminotransferase, aspartate transaminase, total and direct bilirubin, at different weighting coefficients, with the accuracy of about 90%. The model to predict the survival probability by PCAMII was established with good fitness (R2 = 0.9325), providing the simulated survival rates comparable to the clinical data. PCAMII, which is independent of hospital admission time, is a feasible and accurate marker to predict the survival rate of patients with PQ poisoning.

Lymphocyte and its CD4+ and CD8+ subgroup changes after paraquat poisoning.

Paraquat (PQ) poisoning is a significant cause of mortality and morbidity in developing countries. Poor prognostic outcomes have been attributed to the herbicide's toxicity and the lack of effective treatments. Our study aims to investigate the changes in lymphocyte count in both patients who survived and died from PQ poisoning and explore the prognostic value. This is a retrospective case serials observational study. Adult patients admitted with acute PQ poisoning. The notes of 1000 patients who presented with acute PQ poisoning were reviewed. One hundred thirty patients having the T lymphocyte met the inclusion criteria and were grouped into those that survived the poisoning (95) and non-survivors (35). On admission, non-survivors had a higher ingestion volume of PQ and urine PQ concentration as well as higher severity indices (Acute Physiology and Chronic Health Evaluation 2, Sequential Organ Failure Assessment, and Poisoning Severity Score). Patients in the survival group had a higher dosage of immunosuppressant and a longer hospital stay. Leukocytes, especially neutrophils, were higher among non-survivors; however, the converse was found with lymphocytes. T lymphocyte (CD3) count was consistently higher among survivors as well as the subgroups CD4+ and CD8+. No differences in the ratio of CD4/CD8 were found between the groups. Our study has shown that changes in lymphocyte count as its subgroups could indicate a host's immune status and lymphocytes play an important role as a surrogate marker of host immunity, which could be a useful prognostic tool in the assessment of this disease.

Urinary paraquat concentration and white blood cell count as prognostic factors in paraquat poisoning

Purpose: To investigate the effect of white blood cell (WBC) and urinary paraquat (PQ) levels on prognostic factors in patients exposed to PQ intoxication using multivariate logistic regression analysis.Methods: A total of 104 subjects intoxicated with PQ between December 2015 and July 2016 were used in this retrospective study. They comprised patients who survived (n = 78), and patients who died (n = 26). Clinical features and prognostic parameters were analyzed in both groups. Multivariate logistic regression analysis was used to establish a prognostic correlation model based on results from single factor variables.Results: Comparison of demographic and clinical attributes between the two groups, survivors (n = 78) and non-survivors (n = 26), revealed that those who survived were not as old (33.3 ± 9.9 years) as nonsurvivors (41.5 ± 12.9 years). In addition, on admission, it was found that the survivors ingested lower amounts of PQ (31.6 ± 13.8 ml) than non-survivors (67.88 ± 31.2 ml). There were significant differences between the two groups with respect to WBC, neutrophils, lymphocytes, lactate dehydrogenase (LDH), creatine kinase (CK), amylase, uric acid (UA), pH, partial pressure of oxygen (PaO2), base excess (BE), lactic acid, and D-dimer levels (p &lt; 0.05).Conclusion: WBC and urine PQ concentration have strong correlation with prognostic factors in PQ poisoning.Keywords: Paraquat intoxication, Dithionite test, Multivariate logistic analysis, Prognosis, Predictors

Effect of activated charcoal hemoperfusion on renal function in patients with paraquat poisoning.

The present study retrospectively analyzed 19 patients diagnosed with paraquat (PQ) poisoning with the aim to investigate the effect of activated charcoal hemoperfusion on renal function and PQ elimination. The results indicated that 7 patients died and 12 survived. Non-oliguric renal failure occurred in all of the 7 patients who died. Among the 12 surviving patients, 10 had normal renal function and 2 developed non-oliguric renal failure. There was a linear correlation between plasma and urine paraquat concentration prior to and during activated charcoal hemoperfusion. The equation parameters together with the correlation coefficient on admission were as follows: Y=0.5820+1.7348X (R2=0.678; F=35.768; P<0.0001). The equation parameters together with the correlation coefficient were as follows during activated charcoal hemoperfusion: Y=0.6827+1.2649X (R2=0.626; F=50.308; P<0.0001). Therefore, it was concluded that in patients with normal renal function, the elimination kinetics of PQ by the kidneys were only associated with the plasma PQ concentration. Activated charcoal hemoperfusion had little effect on avoiding acute kidney injury in patients with severe PQ poisoning.

Prognostic significance of urine paraquat concentrations of patients with acute paraquat poisoning on admission at the emergency department

Objective: To assess the prognostic significance of urine paraquat concentrations of patients with acute paraquat poisoning on admission at the emergency department. Methods: Patients with acute paraquat poisoning admitted to the emergency department were recruited. Survivors and non-survivors were compared with regard to urinary paraquat concentration. The urinary level predictive of mortality was assessed by receiver operating characteristic curve. Risk factors of mortality were evaluated by regression analysis. Results: The overall mortality rate was 70.9% over the 28-day follow-up period. There was a significant difference in the urine paraquat concentrations recorded on admission between non-surviving and surviving patients ( p = 0.022). Receiver operating characteristic curve analysis revealed that the area under the curve when applied to receiver operating characteristic of the admission urine paraquat concentrations for predicting mortality was 0.854 with a cut-off value of 34.5 µg/mL. The dose of paraquat ingested, arterial lactate, and urine concentration were independent risk factors predicting 28-day mortality. The time interval between ingestion and hemoperfusion, arterial lactate, and urine concentration of paraquat were independent risk factors predicting acute kidney injury, while the partial pressure of carbon dioxide (PaCO2) and urine concentration of paraquat were independent risk factors predicting acute lung injury. Conclusion: The urine concentrations of paraquat on admission at emergency department demonstrated predictive ability for the prognosis of patients with acute paraquat poisoning.

Predictive values of urine paraquat concentration, dose of poison, arterial blood lactate and APACHE II score in the prognosis of patients with acute paraquat poisoning.

The present study investigated the predictive values of urine paraquat (PQ) concentration, dose of poison, arterial blood lactate and Acute Physiology and Chronic Health Evaluation (APACHE) II score in the prognosis of patients with acute PQ poisoning. A total of 194 patients with acute PQ poisoning, hospitalized between April 2012 and January 2014 at the First Affiliated Hospital of P.R. China Medical University (Shenyang, China), were selected and divided into survival and mortality groups. Logistic regression analysis, receiver operator characteristic (ROC) curve analysis and Kaplan-Meier curve were applied to evaluate the values of urine paraquat (PQ) concentration, dose of poison, arterial blood lactate and (APACHE) II score for predicting the prognosis of patients with acute PQ poisoning. Initial urine PQ concentration (C0), dose of poison, arterial blood lactate and APACHE II score of patients in the mortality group were significantly higher compared with the survival group (all P<0.05). Logistic regression analysis revealed that C0, dose of poison and arterial blood lactate correlated with mortality risk of acute PQ poisoning (all P<0.05). ROC curve analysis suggested that the areas under the curve (AUC) values of C0, dose of poison, arterial blood lactate and APACHE II score in predicting the mortality of patients within 28 days were 0.921, 0.887, 0.808 and 0.648, respectively. The AUC of C0 for predicting early and delayed mortality were 0.890 and 0.764, respectively. The AUC values of urine paraquat concentration the day after poisoning (Csec) and the rebound rate of urine paraquat concentration in predicting the mortality of patients within 28 days were 0.919 and 0.805, respectively. The 28-day survival rate of patients with C0 ≤32.2 µg/ml (42/71; 59.2%) was significantly higher when compared with patients with C0 >32.2 µg/ml (38/123; 30.9%). These results suggest that the initial urine PQ concentration may be the optimal index for predicting the prognosis of patients with acute PQ poisoning. Additionally, dose of poison, arterial blood lactate, Csec and rebound rate also have referential significance.

The volume ratio of ground glass opacity in early lung CT predicts mortality in acute paraquat poisoning.

BackgroundPulmonary injury is the main cause of death in acute paraquat (PQ) poisoning. However, whether quantitative lung computed tomography (CT) can be useful in predicting the outcome of PQ poisoning remains unknown. We aimed to identify early findings of quantitative lung CT as predictors of outcome in acute PQ poisoning.MethodsLung CT scanning (64-slide) and quantitative CT lesions were prospectively measured for patients after PQ intoxication within 5 days. The study outcome was mortality during 90 days follow-up. Survival curves were derived by the Kaplan-Meier method, and mortality risk factors were analyzed by the forward stepwise Cox regression analysis.ResultsOf 97 patients, 41 (42.3%) died. Among the eight different types of lung CT findings which appeared in the first 5-day of PQ intoxication, four ones discriminated between survivors and non-survivors including ground glass opacity (GGO), consolidation, pneumomediastinum and “no obvious lesion”. With a cutoff value of 10.8%, sensitivity of 85.4% and specificity of 89.3%, GGO volume ratio is better than adopted outcome indicators in predicting mortality, such as estimated amount of PQ ingestion, plasma or urine PQ concentration, acute physiology and chronic health evaluation (APACHE) II and sequential organ failure assessment (SOFA) scores. GGO volume ratios above 10.8% were associated with increased mortality (hazard ratio, 5.82; 95% confidence interval, 4.77-7.09; P < 0.001).ConclusionsThe volume ratio of GGO exceeding 10.8% is a novel, reliable and independent predictors of outcome in acute PQ poisoning.

Prognosis value of urine paraquat semi-quantitative in the patients with acute paraquat poisoning

To investigate the relationship between semi-quantification of urine paraquat and the severity of acute paraquat poisoning, and to evaluate the prognostic value of the test in patients with acute paraquat poisoning. A total of 179 patients with acute paraquat poisoning were categorized into four groups according to their semi-quantification results of urine paraquat: +group (n = 36), ++group (n = 23), +++ group (n = 25), and ++++group (n = 95). The clinical features, severity of hepatic and renal injuries, respiratory failure, and clinical classification were compared between these four groups. Kaplan-Meier analysis was used to evaluate the survival rate. The 60-day mortality was 45.25% (81/179). The amount of ingestion increased significantly from +group to ++++group (P < 0.05). No patient in +group was found to have serious complications, while most patients in ++++group suffered organ dysfunction or even organ failure. The incidence of acute respiratory failure, renal failure, and hepatic failure in ++++group was significantly higher than that in +group, ++group, and +++group (P < 0.05). The urine paraquat concentration was positively correlated with the clinical severity of acute paraquat poisoning (Spearman correlation coefficient = 0.720, P < 0.01). Kaplan-Meier survival analysis showed that the mortality of ++++group (73.7%) was significantly higher than that of +++group (40%), ++group (4.3%), and +group (0%) (P < 0.05). The semi-quantification of urine paraquat is a promising test in evaluating the severity of acute paraquat poisoning. This test can be used to guide therapy and to predict the outcomes of patients suffering acute paraquat poisoning.

Hypokalemia and Hypothermia are Associated With 30-day Mortality in Patients With Acute Paraquat Poisoning

Clinical predictors associated with acute paraquat (PQ) poisoning have not been systematically studied. To identify independent predictors of death in patients with acute PQ poisoning. This is a retrospective study executed in the emergency department of a university hospital. One hundred three consecutive patients poisoned with PQ between January 1999 and December 2004 were enrolled. Urine PQ concentration, electrolyte and renal function, detailed history, and Acute Physiology and Chronic Health Evaluation II were extracted from medical records. The outcome measure was 30-day mortality. Multivariate analysis was done by Cox-proportional hazard regression model. Receiver operating characteristics area under the curve was calculated for selected predictors. The crude 30-day mortality was 67.9% (70 of 103). Independent predictors of death were acute renal failure (hazard ratio, 3.53; 95% confidence interval, 1.97-6.32), hypokalemia (2.07, 1.21-3.51), hypothermia (2.91, 1.67-5.07), suicide (2.11, 1.04-4.29), and self-reported ingested dose (2.06, 1.38-3.06). The receiver operating characteristics area under the curve of serum potassium concentrations, maximal urine PQ concentrations, and Acute Physiology and Chronic Health Evaluation II scores were 0.75 (95% confidence interval, 0.60-0.81), 0.71 (0.66-0.84), and 0.80 (0.71-0.88), respectively. Under the cutoff value of 3.6 mEq/L, hypokalemia had a sensitivity of 75% and specificity of 54% in predicting mortality. The identified risk factors may allow better identification of those at greater mortality risk. Future development of a tailored clinical scoring system incorporating the identified risk factors for acute PQ poisoning may be of great help.

뇨중 파라쿼트(paraquat)측정용 진단 시험지의 개발

Paraquat is an effective and widely used herbicide, but it is also very toxic to humans. It is well-known that urine paraquat concentration is one of the most important prognostic indicator for paraquat-poisoning. Quantitative analysis of paraquat, however, are not generally used in clinical laboratories. In this work, a new test strip to detect paraquat concentration using sodium dithionite in urine was developed. Using these second-derivative method, the test strip prepared in borate buffer (pH 8.0), 0.25 M PVP, and decanol showed not only better color reaction but also an excellent application possibility to be used in automatic analyzer.

Evaluation of paraquat concentrations in paraquat poisoning.

The toxicological significance of paraquat concentrations in paraquat poisonings was evaluated by means of multivariate analysis methods. Paraquat could be determined by a newly developed procedure, which involved thin-layer chromatography with flame ionization detector (TLC-FID) and solid-phase extraction with a disposable octadecylsilane cartridge. This new method proved to be simple, rapid and reliable for the analysis of paraquat in our seven cases of suicidal poisoning. The relationship between plasma paraquat concentration (C) and time from ingestion (T) could be best described by the following functions. The regression equation of fatal cases was ln[ln(C X 1000)] = 2.5453 - 0.2114 lnT. The regression equation of survivors was ln[ln(C X 1000)] = 2.1041 - 0.2826 lnT. The discriminant function (D) to separate the fatal and survival cases was D = 1.3114 - 0.1617 lnT - 0.5408 [ln(C X 1000)] (fatal cases: D less than 0, survivors: D greater than 0). The discriminant function was demonstrated to have a high reliability for the toxicological significance in our seven poisoned patients. The significant correlation between plasma paraquat concentration and urine paraquat concentration (C') in our cases was obtained. The regression equation was lnC' = 0.953 lnC + 1.409. This also indicated that urinary concentrations are 3.3 - 4.5 times greater than plasma concentrations. The multiple regression equation among plasma paraquat concentration, time from ingestion, and the ingested volume (V) of Gramoxone (trade name of paraquat), was lnC = 0.009V - 0.232T + 3.612. It is suggested that the determination of paraquat is of great value, and that these data are useful in assessing the severity and predicting the outcome of poisoning for forensic and clinical purposes.

Prognostic value of plasma and urine paraquat concentration.

A non-exponential mathematical equation was used to extrapolate the 'predictive line' for plasma paraquat concentrations beyond 24 h. Plasma paraquat concentrations were measured in 30 patients who were admitted more than 24 h after overdose. The extrapolated line accurately predicted the outcome in 27 of these 30 patients. Urine paraquat concentrations were measured in 53 patients. All patients with urine paraquat concentrations of less than 1 mg/l (colourless or light blue test result using the colorimetric test) within 24 h of overdose survived. In contrast, patients with urine paraquat concentrations of more than 1 mg/l had a high probability of death. Even if plasma paraquat concentrations have a higher predictive value, urine data may contribute to a more rapid evaluation of prognosis.