Anticoagulant rodenticide ingestion: Who will develop coagulopathy?

Introduction: Development of coagulopathy after anticoagulant rodenticide ingestion varies among patients. This study aimed to identify factors that were associated with coagulopathy after anticoagulant rodenticide ingestion. Methods: This was a retrospective cohort study, conducted in the Hong Kong Poison Information Centre. All patients who reported rodenticide exposure and presented to the Accident and Emergency Department from 1 January 2010 to 31 December 2019 were recruited. Coagulopathy was defined as International Normalized Ratio of 1.3 or above. Results: One hundred sixty-nine patients were included in the final analysis. The median age was 44 years old. Forty-nine patients developed coagulopathy (International Normalized Ratio ⩾1.3). Univariate analysis (at p < 0.05) showed that age (p = 0.003), ingestion of first-generation anticoagulant rodenticide (p = 0.017), ingestion of more than one pack (p < 0.001), intentional ingestion (p = 0.002), hypoalbuminemia (p < 0.001), elevated alanine aminotransferase level (p = 0.041) and abnormal estimated glomerular filtration rate (p = 0.005) on presentation, and co-ingestion with paracetamol (p = 0.018) were associated with coagulopathy after anticoagulant rodenticide ingestion. Among these, ingestion of more than one pack (p < 0.001; odds ratio = 19.8; 95% confidence interval = 6.78–65.7), ingestion of first-generation anticoagulant rodenticide (p = 0.006; odds ratio = 5.2; 95% confidence interval = 1.96–15.2), hypoalbuminemia (p < 0.001; odds ratio = 22.4; 95% confidence interval = 6.17–99.0) and elevated alanine aminotransferase level on presentation (p = 0.039; odds ratio = 7.11; 95% confidence interval = 1.58–33.1) were statistically significant in the multivariate analysis. Conclusion: Ingestion of more than one pack and ingestion of first-generation anticoagulant rodenticides were significantly associated with the development of coagulopathy after anticoagulant rodenticide ingestion. Patients who developed hypoalbuminemia or elevated alanine aminotransferase level as a result of anticoagulant rodenticide ingestion were also significantly associated with the development of coagulopathy.