Prognosis and survival analysis of paraquat poisoned patients based on improved HPLC-UV method

Paraquat and Diquat: Recent Updates on Their Pretreatment and Analysis Methods since 2010 in Biological Samples

Paraquat (PQ) and diquat (DQ) are quaternary ammonium herbicides which have been used worldwide for controlling the growth of weeds on land and in water. However, PQ and DQ are well known to be toxic. PQ is especially toxic to humans. Moreover, there is no specific antidote for PQ poisoning. The main treatment for PQ poisoning is hemoperfusion to reduce the PQ concentration in blood. Therefore, it is essential to be able to detect PQ and DQ concentrations in biological samples. This critical review summarizes the articles published from 2010 to 2022 and can help researchers to understand the development of the sample treatment and analytical methods for the determination of PQ and DQ in various types of biological samples. The sample preparation includes liquid-liquid extraction, solid-phase extraction based on different novel materials, microextration methods, and other methods. Analytical methods for quantifying PQ and DQ, such as different chromatography and spectroscopy methods, electrochemical methods, and immunological methods, are illustrated and compared. We focus on the latest advances in PQ and DQ treatment and the application of new technologies for these analyses. In our opinion, tandem mass spectrometry is a good choice for the determination of PQ and DQ, due to its high sensitivity, high selectivity, and high accuracy. As far as we are concerned, the best LOD of 4 pg/mL for PQ in serum can be obtained.

Prediction of mortality and morbidity following paraquat poisoning based on trend of liver and kidney injury

Background

Paraquat is a non-selective herbicide that causes severe tissue damage in various organs including the liver and kidney. The aim of this study was to determine the trend of the liver and kidney injury in patients with paraquat poisoning.

Methods

This retrospective cross-sectional study was performed at the Khorshid Hospital referral poisoning emergency center. The medical records of all patients with acute paraquat poisoning admitted from March 2017 to October 2020 were reviewed. Demographic factors, liver and kidney function tests and outcomes were recorded. Patients were divided into two groups based on the outcome of mortality (death or survived). The two groups were compared in terms of changes in creatinine and liver enzymes during hospitalization.

Results

A significant difference in mean creatinine levels between the two groups was observed from the third day after admission. The peak median Cr was 3.5 mg/dl for deceased patients in day 6 and 1.47 mg/dl for survived patients on 4th day. Minor elevations of ALT and AST were present in those who died. Logistic regression analysis shows patients who had level of creatinine higher than normal from the 2nd to 6th day post overdose, the risk of mortality was 4.83 to 7.44 times more than patients with normal creatinine level. The mean (SD) area under the curve for outcome prediction was reported to be excellent for creatinine on the 8th day post overdose (85.7 ± 13.2). Creatinine was higher than 2 on the 8th day post ingestion and had a sensitivity 100% and specificity 85.7% for mortality prediction (P value, 0.05).

Conclusions

The risk of mortality secondary to paraquat ingestion was highly associated with a rise in creatinine. Minor elevations of ALT and AST were also present in those who died. The creatinine concentration on different days post overdose can be helpful in predicting the severity of poisoning especially when the serum paraquat levels are not available.

Plasma Concentration After the First Hemoperfusion has a High Predictive Value in Medium Level Acute Paraquat-Poisoned Patients

BACKGROUND

Paraquat ( PQ) is very poisonous to humans and animals and there is no effective clinical antidote . The efficacy of hemoperfusion (HP) treatment for PQ poisoning remains controversial. To explore new ways to predict the prognosis of patients with acute PQ poisoning and assist in the development of better hemopurification treatment strategies.

METHODS

The clinical data of patients who were intoxicated with PQ through contact were diagnosed with PQ poisoning by high-performance liquid chromatography. Samples were collected by the Emergency Intensive Care Unit of the First Affiliated Hospital of Wenzhou Medical University from January 2012 to November 2016. Based on the prognosis, the patients were grouped into survival and death groups. Comparisons of the differences in the clinical indexes were performed, including the initial concentration of PQ at admission, PQ concentration after first HP, the number of HP cartridges used for the first hemoperfusion, whether HP was combined with continuous renal replacement therapy, and the number of concurrent organ injuries between the 2 groups. In addition, data were analyzed using multivariate logistic regression models and receiver operating characteristic curves. Moreover, prognostic factors in patients with acute PQ poisoning were analyzed.

RESULTS

Overall, 128 patients with acute PQ poisoning were enrolled in this study. The median plasma PQ concentrations of the patients at admission were 21 and 834 ng/mL (range: 50-1,099,118 ng/mL). The multiple logistic regression model revealed that the initial concentration of PQ and the PQ concentration after the first perfusion were independent risk factors for death in patients with acute PQ poisoning. The PQ concentration in the survival group after the first HP was <516 ng/mL and was mainly distributed at approximately 100 ng/mL. The percentage of patients whose concentration after the first HP was <516 ng/mL in the death group was only 19%.

CONCLUSIONS

The initial plasma PQ concentration after admission and PQ concentration after the first HP are risk factors for death in patients with acute PQ poisoning. Moreover, PQ concentration after the first HP had a high predictive value for death. When the initial plasma PQ concentration after admission ranges from 50 ng/mL to 5000 ng/mL, the rapid reduction in plasma PQ concentration after HP treatment could improve the prognosis of patients with acute PQ poisoning.

Development and Validation of a Radiomics Nomogram for Prognosis Prediction of Patients with Acute Paraquat Poisoning: A Retrospective Cohort Study

Objective

To evaluate the efficiency of a radiomics model in predicting the prognosis of patients with acute paraquat poisoning (APP).

Materials and Methods

Chest computed tomography images and clinical data of 80 patients with APP were obtained from November 2014 to October 2017, which were randomly assigned to a primary group and a validation group by a ratio of 7 : 3, and then the radiomics features were extracted from the whole lung. Principal component analysis (PCA) and least absolute shrinkage and selection operator (LASSO) regression were used to select the features and establish the radiomics signature (Rad-score). Multivariate logistic regression analysis was used to establish a radiomics prediction model incorporating the Rad-score and clinical risk factors; the model was represented by nomogram. The performance of the nomogram was confirmed by its discrimination and calibration.

Result

The area under the ROC curve of operation was 0.942 and 0.865, respectively, in the primary and validation datasets. The sensitivity and specificity were 0.864 and 0.914 and 0.778 and 0.929, and the prediction accuracy rates were 89.5% and 87%, respectively. Predictors included in the individualized predictive nomograms include the Rad-score, blood paraquat concentration, creatine kinase, and serum creatinine. The AUC of the nomogram was 0.973 and 0.944 in the primary and validation datasets, and the sensitivity and specificity were 0.943 and 0.955, respectively, in the primary dataset and 0.889 and 0.929 in the validation dataset, and the prediction accuracy was 94.7% and 91.3%, respectively.

Conclusion

The radiomics nomogram incorporates the radiomics signature and hematological laboratory data, which can be conveniently used to facilitate the individualized prediction of the prognosis of APP patients.

A metal-catex composite electrode for determination of paraquat in various samples by Ad-differential pulse cathodic stripping voltammetry

In this work, a novel kind of metal-catex composite electrode for determination of paraquat (PQ) by adsorptive differential pulse voltammetry is introduced. The metal-catex composite electrode was fabricated by cathodic electropolymerization of p-nitrophenol and p-nitrobenzoic acid in the presence of tin (II) chloride as a scaffold for composite structure on prepared glassy carbon electrode. Electropolymerization was carried out in sodium acetate medium. The surface of the fabricated electrode was characterized with field emission scanning electron microscope and energy-dispersive X-ray spectrometry. The obtained results show that there are Sn nanoparticles in the structure of the catex-composite. Chemical structure of metal-catex composite electrode was investigated using FTIR (ATR), ¹³C NMR, H NMR and a suitable mechanism for electropolymerization has been proposed. This metal-catex composite electrode was applied for determinations of PQ using sodium acetate buffer solutions at pH = 6.5 as an electrolyte solution. All parameters influencing the performance of the fabricated electrode were studied and optimized. The proposed electrode exhibits good linearity versus PQ concentration in the range of 3.8 × 10^-8 to 7.7 × 10^-7 mol L^-1 and shows a manifold increase in sensitivity (more than 30 times) as compared to the glassy carbon electrode. The LOQ of this electrode was 7.78 × 10^-9 mol L^-1, which is comparable with that of other electrochemical methods. The mean, standard deviation and relative standard deviation for seven repetitive determinations of paraquat (7.78 × 10^-8 mol L^-1) were measured to be 7.75 × 10^-8 mol L^-1, ±0.29 × 10^-8 mol L^-1, and 3.75% respectively. This electrode was applied for the determination of paraquat in natural water, natural juice, potatoes and onions. The introduced electrode shows good stability with repeated use and over long periods (about 20 days). There is a good agreement between the results for water analysis by this method and the standard method.

Metabolomics Analysis in Acute Paraquat Poisoning Patients Based on UPLC-Q-TOF-MS and Machine Learning Approach

Most paraquat (PQ) poisoned patients died from acute multiple organ failure (MOF) such as lung, kidney, and heart. However, the exact mechanism of intoxication is still unclear. In order to find out the initial toxic mechanism of PQ poisoning, a blood metabolomics study based on ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and efficient machine learning approach was performed on 23 PQ poisoned patients and 29 healthy subjects. The initial PQ plasma concentrations of PQ poisoned patients were >1000 ng/mL, and the blood samples were collected at before first hemoperfusion (HP), after first HP, and after last HP. The results showed that PQ poisoned patients all differed from healthy subjects, whatever they were before or after first HP or after last HP. The efficient machine learning approaches selected key metabolites from three UPLC/Q-TOF-MS data sets which had the highest classification performance in terms of classification accuracy, Matthews Correlation Coefficients, sensitivity, and specificity, respectively. The mass identification revealed that the most important metabolite was adenosine, which sustained in low level, regardless of whether PQ poisoned patients received HP treatment. In conclusion, decreased adenosine was the most important metabolite in PQ poisoned patients. The metabolic disturbance caused by PQ poisoning cannot be improved by HP treatment even the PQ was cleared from the blood.

Diagnostic value of complete blood count in paraquat and organophosphorus poisoning patients

Complete blood count (CBC) is one of the most extensively used tests in clinical practice. In order to determine the diagnostic value of the CBC in paraquat (PQ) and organophosphorus (OPPs) poisoning, the CBC indices of PQ- and OPPs-poisoned patients were investigated in this study. A total of 96 PQ poisoning patients, 90 OPPs poisoning patients, and 188 healthy subjects were included in this study. The PQ- and OPPs-poisoned patients were divided into different groups according to their clinical symptoms. All CBC indices were analyzed by Fisher discriminant, partial least-squares discriminant analysis (PLS-DA), variance analysis, and receiver operating characteristic (ROC). The discriminant results showed that 87.7% of original grouped cases correctly classified between PQ-poisoned patients, OPPs-poisoned patients, and healthy subjects. The PLS-DA results showed that the important variable order was different in PQ- and OPPs-poisoned patients. Both white blood cell (WBC) and neutrophil (NE) counts were the most important indexes in PQ- and OPPs-poisoned patients. In OPPs poisoning patients, WBC and NE showed statistical differences between the severe poisoning group and the moderate poisoning group. Their areas under the ROC curve (AUC) were 0.673 (WBC) and 0.669 (NE), which were higher than cholinesterase (CHE; AUC 0.326). In conclusion, the CBC indices had a diagnostic value in PQ and OPPs poisoning; WBC and NE were the first responses and had clinical significance in PQ and OPPs poisoning; moreover, they are better than CHE in diagnosing OPPs poisoning.

Early Metabolome Profiling and Prognostic Value in Paraquat-Poisoned Patients: Based on Ultraperformance Liquid Chromatography Coupled To Quadrupole Time-of-Flight Mass Spectrometry

Paraquat (PQ) has caused countless deaths throughout the world. There remains no effective treatment for PQ poisoning. Here we study the blood metabolome of PQ-poisoned patients using ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS). Patients were divided into groups according to blood PQ concentration. Healthy subjects served as controls. Metabolic features were statistically analyzed using multivariate pattern-recognition techniques to identify the most important metabolites. Selected metabolites were further compared with a series of clinical indexes to assess the prognostic value. PQ-poisoned patients showed substantial differences compared with healthy subjects. Based on variable of importance in the project (VIP) values and statistical analysis, 17 metabolites were selected and identified. These metabolites well-classified low PQ-poisoned patients, high PQ-poisoned patients, and healthy subjects, which was better than that of a complete blood count (CBC). Among the 17 metabolites, 20:3/18:1-PC (PC), LPA (0:0/16:0) (LPA), 19-oxo-deoxycorticosterone (19-oxo-DOC), and eicosapentaenoic acid (EPA) had prognostic value. In particular, EPA was the most sensitive one. Besides, the levels of EPA was correlated with LPA and 19-oxo-DOC. If EPA was excessively consumed, then prognosis was poor. In conclusion, the serum metabolome is substantially perturbed by PQ poisoning. EPA is the most important biomarker in early PQ poisoning.

A new machine-learning method to prognosticate paraquat poisoned patients by combining coagulation, liver, and kidney indices

The prognosis of paraquat (PQ) poisoning is highly correlated to plasma PQ concentration, which has been identified as the most important index in PQ poisoning. This study investigated the predictive value of coagulation, liver, and kidney indices in prognosticating PQ-poisoning patients, when aligned with plasma PQ concentrations. Coagulation, liver, and kidney indices were first analyzed by variance analysis, receiver operating characteristic curves, and Fisher discriminant analysis. Then, a new, intelligent, machine learning-based system was established to effectively provide prognostic analysis of PQ-poisoning patients based on a combination of the aforementioned indices. In the proposed system, an enhanced extreme learning machine wrapped with a grey wolf-optimization strategy was developed to predict the risk status from a pool of 103 patients (56 males and 47 females); of these, 52 subjects were deceased and 51 alive. The proposed method was rigorously evaluated against this real-life dataset, in terms of accuracy, Matthews correlation coefficients, sensitivity, and specificity. Additionally, the feature selection was investigated to identify correlating factors for risk status. The results demonstrated that there were significant differences in the coagulation, liver, and kidney indices between deceased and surviving subjects (p<0.05). Aspartate aminotransferase, prothrombin time, prothrombin activity, total bilirubin, direct bilirubin, indirect bilirubin, alanine aminotransferase, urea nitrogen, and creatinine were the most highly correlated indices in PQ poisoning and showed statistical significance (p<0.05) in predicting PQ-poisoning prognoses. According to the feature selection, the most important correlated indices were found to be associated with aspartate aminotransferase, the aspartate aminotransferase to alanine ratio, creatinine, prothrombin time, and prothrombin activity. The method proposed here showed excellent results that were better than that produced based on blood-PQ concentration alone. These promising results indicated that the combination of these indices can provide a new avenue for prognosticating the outcome of PQ poisoning.

Effects of hemoperfusion and continuous renal replacement therapy on patient survival following paraquat poisoning

Mortality in patients with paraquat (PQ) poisoning is related to plasma PQ levels. Concentrations lower than 5,000 ng/mL are considered critical but curable. This study assessed the effects of hemoperfusion (HP) and continuous renal replacement therapy (CRRT) on the survival of PQ-poisoned patients with plasma PQ levels below 5,000ng/mL. We analyzed the records of 164 patients with PQ poisoning who were treated at the First Affiliated Hospital of Wenzhou Medical University in China between January 2011 and May 2015. We divided these patients into six sub-groups based on baseline plasma PQ levels and treatment, compared their clinical characteristics, and analyzed their survival rates. Patient sub-groups did not differ in terms of age, sex, time between poisoning and hospital admission, or time to first gavage. Biochemical indicators improved over time in all sub-groups following treatment, and the combined HP and CRRT treatment yielded better results than HP or CRRT alone. Fatality rates in the three treatment sub-groups did not differ among patients with baseline plasma PQ levels of 50–1,000 ng/mL, but in patients with 1,000–5,000 ng/mL levels, the mortality rate was 59.2% (HP treatment group), 48% (CRRT treatment group), and 37.9% (combined treatment group). Mortality rates were higher 10–30 days after hospitalization than in the first 10 days after admission. In the early stages of PQ poisoning, CRRT is effective in reducing patient fatality rates, particularly when combined with HP. Our data could be useful in increasing survival in acute PQ poisoning patients.