Evaluation of the accuracy of “ChE check mobile” in measurement of acetylcholinesterase in pesticide poisoning

Abstract

Background: Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are used in clinical management to confirm the diagnosis and indicate the severity of organophosphorus and carbamate poisoning. ChE check mobile is a new portable cholinesterase testing system developed in Germany. The study aims to evaluate the accuracy of ChE check mobile compared to the standard reference method and Test-mate ChE system. Methods: Patients with organophosphorus and carbamate poisoning were recruited from two general hospitals in Sri Lanka between September 2013 and November 2014. The AChE was measured using the three methods. Results: Blood samples were collected from 185 self-poisoned patients (170 organophosphorus and 15 carbamate) and 20 normal individuals. ChE check mobile correlated well with spectrophotometer readings (Pearson's correlation coefficient 0.87) but gave higher values (Mean bias for AChE: þ6.55 (95% CI: À11 to 24) U/g Hb). A similar positive bias from Test-mate results was also observed. Applying a correction factor derived from the volunteer samples (dividing by 1.353) greatly improved agreement in pesticide poisoned patients. Conclusions: ChE check mobile system allowed for rapid determination of AChE activity but gave somewhat higher AChE compared to other methods. Applying a correction factor of 1.353 provide a good agreement to both reference and Test-mate ChE machine in this setting.

Cholinesterase alterations in delirium after cardiosurgery: a German monocentric prospective study

“…Working conditions and technical data for this device are published online 28. Previously, detailed information on the accuracy of this device have been published before having demonstrated acceptable reliability for the measurement of cholinesterases 29. Further, this device has been used in the context of POD before 23 24…”

Diagnostics and treatment of nerve agent poisoning—current status and future developments

“…26 By contrast, most laboratories are not capable of determining AChE activity. 27 Therefore, even though the inhibition of the BChE does not necessarily result in clinical signs, it is assayed for in the ChE check mobile and the Testmate ChE devices as a comparable and readily available indicator for OP poisoning. 6,9 The main target of all OP compounds, including nerve agents, is the pivotal enzyme AChE.…”

“…BChE activity (also known as plasma ChE) is determined in routine laboratory tests as a liver function parameter 26 . By contrast, most laboratories are not capable of determining AChE activity 27 . Therefore, even though the inhibition of the BChE does not necessarily result in clinical signs, it is assayed for in the ChE check mobile and the Test‐mate ChE devices as a comparable and readily available indicator for OP poisoning 6,9 .…”