Indian Journal of Medical Biochemistry

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VOLUME 21 , ISSUE 2 ( July-December, 2017 ) > List of Articles


Utility of Serum Paraoxonase Levels with reference to Severity of Organophosphorus Poisoning

Hettagowdanahally V Rahul, N Asha Rani, N Asha Rani

Citation Information : Rahul HV, Rani NA, Asha Rani N. Utility of Serum Paraoxonase Levels with reference to Severity of Organophosphorus Poisoning. Indian J Med Biochem 2017; 21 (2):101-105.

DOI: 10.5005/jp-journals-10054-0030

License: CC BY 3.0

Published Online: 01-06-2013

Copyright Statement:  Copyright © 2017; The Author(s).



Organophosphorus (OP) compounds are widely used insecticides for agricultural and domestic purposes. Easy availability and less awareness regarding the toxicity caused by these compounds have resulted in high morbidity and mortality in India. Early diagnosis and initiation of treatment are required to reduce the mortality rate for which laboratory evaluation plays a vital role, in addition to various clinical scoring systems.

Materials and methods

A cross-sectional study was carried out for a period of 2 months. Forty clinically diagnosed acute OP poisoning cases admitted in emergency units formed the study subjects. Serum was used for the estimation of cholinesterase, for both basal and salt stimulated paraoxonase (PON) activity. Peradeniya organophosphorus poisoning (POP) scale was used as a tool to categorize patients into mild (0—3 score), moderate (4—7 score), and severe (8—11 score) poisoning.


The mean age of the study participants was 31.9 ± 14.4 years. Seventy-five percent of the participants were males and 25% were females. Chlorpyrifos was the most common OP compound consumed by the study participants. There was a significant decrease in the serum cholinesterase activity (p = 0.001) and salt-stimulated PON activity (p = 0.016) as the severity increased. Serum cholinesterase and POP score showed statistically significant negative correlation (p = 0.003). There was a linear positive correlation between serum cholinesterase and serum PON activity, but the correlation was significant only with salt-stimulated PON activity (p = 0.005).


The results suggest that subjects with higher levels of PON activity may have better detoxifying capacity toward OP poisoning.

How to cite this article

Rahul HV, Rani NA, Nusrath A. Utility of Serum Paraoxonase Levels with reference to Severity of Organophosphorus Poisoning. Indian J Med Biochem 2017;21(2):101-105.

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