Evaluating Diagnostic Value of Electrophysiological Testing (EMG-NCV) Compared to the Activity Level of Acetylcholinesterase in Serum and Red Blood Cells of Patients with Moderate to Severe Organophosphate Poisoning

Authors

1 Forensic Toxicology Specialist, Associate Professor of Mashhad University of Medical Sciences, Mashhad, Iran

2 Fellowship of Clinical Toxicology, Assistant Professor of Mashhad University of Medical Sciences, Mashhad, Iran

3 Forensic Toxicology Specialist, Assistant Professor of Shahid Beheshti University of Medical Sciences, Tehran, Iran

10.5812/rijm.44107

Abstract

Abstract Background: Organophosphate compounds cause poisoning and death more than any other insecticide. These toxins can cause peripheral neuropathy which is delayed for about 3 - 6 weeks and no method has been known for predicting the incidence. It has been claimed that electrophysiological tests (EMG - NCV) can help in predicting the disorder. Objectives: The main purpose of this research was to study EMG - NCV tests in patients with moderate to severe organophosphate poisoning. Methods: This was a cross-sectional study conducted on patients with moderate to severe organophosphate poisoning from 2014 to 2016 in Imam Reza hospital of Mashhad. The minimum sample size was calculated as 68 patients and then all data was collected on the basis of inclusion and exclusion criteria using data collection form designed by the researcher, and finally data were analyzed using SPSS V.21 software, descriptive tests (including mean, median, mode) and analytical tests (K square, ANOVA). Results: Of all 78 patients with the mean age of 27.5010.0, 45 were female and the rest were male. Totally 29.5% of the patients had abnormal EMG - NCV. Although no significant differences were observed between electro diagnostic tests (EMG - NCV) and age, gender, clinical symptoms and levels of acetylcholinesterase serum activity, the relationship between EMG - NCV and RBC levels of acetylcholinesterase activity was significant. Conclusions: Electrophysiological tests are not associated with clinical symptoms (muscle weakness) and they cannot be considered as a determining factor to discharge the patients; therefore, careful examination of the patients or evaluating the level of AChE activity in red blood cells is needed.

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