The use of serial measurement of plasma cholinesterase in the management of acute poisoning with organophosphates and carbamates

OBJECTIVE: To evaluate the benefits of using serial measurements of plasma cholinesterase (butyrylcholinesterase, BuChE) activity in the management of cholinesterase inhibitor insecticidal poisoning. METHOD: After establishing and validating BuChE activity test, and making it available for clinical service in the toxicology laboratory at Jordan University Hospital. Serial measurements of BuChE were performed on samples taken from 10 symptomatic patients presented with the manifestations of poisoning due to acetylcholinesterase inhibitor insecticides during the year 2001. The number of serial repeats of BuChE activity tests ranged from 2 to 4 and from 8 to 11 for patients with carbamates and organophosphates (OPs) poisoning, respectively. The results of serial measurement of BuChE obtained from each patient's samples were used to draw a curve; three different types of curves were obtained from all patients samples. RESULT: The obtained curves were found to follow our three proposed curves, which support our point view regarding the importance of the proposed curves in the differential diagnosis and treatment of cholinesterase inhibitor pesticides poisoning. CONCLUSION: This study pointed out the importance of utilizing serial measurements of BuChE activity in the diagnosis and the management of organophosphates and carbamates poisoning. The BuChE activity results were used to support diagnostic and prognostic criteria that guided patient management and follow up. Applying those curves to large number of patients' samples will enhance its credibility. The study also demonstrated the importance of direct contract between toxicologist and physician in treatment of the pesticides poisoned patients.