Correlation of Pseudocholinesterase Level with Clinical, Biochemical Parameters Including Cardiac Profile and the Outcome in Organophosphorus Poisoning.

Background: Poisoning is a significant health hazard and a leading cause of morbidity and mortality worldwide. India, being a predominantly agrarian country, routinely employs organophosphate (OP) pesticides in farming, and they are readily available "over the counter." OPs exert their toxicity by interfering with the normal function of acetylcholine, an essential neurotransmitter throughout the autonomic and central nervous systems. Due to the limited availability of facilities and resources in health-care systems, and economically restraining patients, it is necessary to rely more on clinical features to assess the severity of poisoning and manage the condition properly.

Methodology: It was a hospital-based prospective observational study that included patients aged >13 years in a tertiary care hospital. All patients were clinically evaluated based on their history and examination. The diagnosis was made based on characteristic clinical manifestations or evidence of exposure to organophosphorus compounds (corroborative evidence such as empty containers and the odor of gastric aspirates). Clinical severity was assessed and categorized according to the Peradeniya Organophosphorus Poisoning Scale (POP scale). A score of 0-3 is considered mild poisoning, 4-7 as moderate poisoning, and 8-11 as severe poisoning.

Results: Out of the 50 patients enrolled in the study, 17 (34.00%) were aged <20 years, 19 (38%) were in the 20-30 years age group, and 14 (28%) were aged >30 years. Ingestion is the only mode of exposure to poisoning. None of the patients had history of contact or inhalational exposure. Of the 50 cases, 12 (24.0%) were in the mild category, 26 (52.0%) in the moderate category, and 12 (24%) in the severe category on the POP grading. A comparison of the mean serum pseudocholinesterase, troponin-T, and pro-BNP levels with severity was performed. In mild OP poisoning, the mean serum PChE level was 2766.58 ± 1120.44; in moderate, it was 1969.35 ± 1330.07, and in severe, it was 701.83 ± 961.17. Pseudocholinesterase levels decreased progressively with increasing clinical severity from mild-to-severe cases, and this association was statistically significant (P < 0.001). Two-dimensional echocardiography screening done in all patients did not show any significant abnormalities.

Conclusion: This study shows that serum PCE is reduced in OP poisoning and correlates with the clinical severity grading done by the POP scale and is also associated with an increase in the duration of intensive care unit stay. No significant evidence of direct cardiac injury was observed in this study. A low Glasgow Coma Scale score and an increased respiratory rate at presentation are associated with poor outcomes.