Background: toxicity following acute ingestion of large amount of methotrexate is rarely reported, yet accidental daily dosing of methotrexate can result in life-threatening toxicity.
Objective: This study aims to evaluate the outcome of cases of methotrexate toxicity reported to the Poison Control Center of Ain Shams University Hospitals, Egypt with highlight on causes of mortality, frequency of adverse effect and treatment offered.
Methods: A prospective study conducted on patients suffering from methotrexate toxicity admitted to the Poison Control Center from January 2015 till December 2018. Twenty-seven patients were included and were classified into two groups: Survivors and Non-survivors. The following variables were studied: presence or absence of vomiting, diarrhea, stomatitis, dysphagia, melena, rash, respiratory distress and treatment given to the patients. Venous samples were drawn for complete blood picture, renal function test and liver enzymes. Electrocardiogram and chest X- ray were performed for all patients on admission and repeated if needed.
Results: Our results revealed that 41% of patients had no effect, minor effect (7%), moderate effect (4%), major manifestation (22%). Death was reported in 26% of the cases. The majority of patients (63%) were due to therapeutic errors. Accidental and suicidal patients were asymptomatic. Major manifestations and death were reported in cases of therapeutic error. Death was mainly due to respiratory complications.
Conclusion: Errors with methotrexate treatment was the main cause of toxicity and respiratory complication was the most common cause of mortality. Strategies to reduce these harms are highly required.