Context: Organophosphorus (OP) compounds are the most common suicidal poisons in the developing countries. A recent study from south India reported mortality rate of 4% in OP poisoning cases.These compounds exert their toxicity by allowing acetylcholine to overact at its receptors in the central and peripheral nervous system. Aims: The aim was to study the variations in the hematological parameters in patients of OP compound poisoning and clinically correlate these findings with the severity of poisoning and assess the effect of treatment on them. Methods and Material: Patients with definite history of OP compound poisoning and decreased serum levels of pseudocholinesterase (PCE) enzyme were included in the study. The serum pseudocholinesterase levels were estimated at admission. Another EDTA blood sample was subjected to complete blood picture analysis. The same methodology was repeated after treatment. OP poisoning patients were classified into latent, mild, moderate and severe based on serum pseudocholinesterase levels. Concurrently the changes in hematological parameters were correlated with the severity of poisoning before and after treatment. Statistical Analysis Used: Statistical analysis of the percentages, mean, range and chisquare test for associations and Wilcoxon signed-rank test to assess the association were done, with p-value of <0.05 taken as statistical significance at 95% confidence interval Results: The present study showed significant decrease (p<0.001) in serum cholinesterase levels in moderate to severe poisoning. Out of 164 cases, 80 of them showed neutrophilia at admission and reached to values of normal reference range in 81.2% of the cases post-treatment while neutophilia persisted in 18.8% despite treatment which is statistically significant. Conclusions: This study concludes that in resource poor settings where estimation of plasma ChE levels cannot be determined then hematological parameters like total and differential leucocyte counts can predict response to treatment and recovery from OP poisoning.

Keywords: Organophosphorus Compounds; Poisoning; Serum Pseudocholinesterase; Neutrophilia.