[Acute toxicity by methotrexate used for abortion purpose. Case report]

Area of Science:

• Toxicology
• Pharmacology
• Reproductive Medicine

Background:

• Methotrexate is used for medical abortions, typically at therapeutic doses.
• High-dose methotrexate (macrodose) can cause severe cytotoxic effects and toxicity.
• Septic abortion is a life-threatening complication requiring prompt management.

Observation:

• A 16-year-old patient presented with severe sepsis, fever, nausea, and vomiting after receiving a 500 mg intramuscular dose of methotrexate and misoprostol for an 11.4-week intrauterine fetal death.
• Initial diagnosis included severe sepsis secondary to septic abortion, oral candidiasis, and acute methotrexate poisoning.
• The patient was managed with hydration, antibiotics, folinic acid, and urine alkalization, showing gradual improvement over 12 days.

Findings:

• This case highlights the severe adverse effects of macrodose methotrexate, distinct from therapeutic-dose regimens.
• Premature and empirical administration of folinic acid combined with urine alkalization was crucial for the patient's recovery.
• No prior case reports document the use of macrodose methotrexate for abortion or its specific management.

Implications:

• This case underscores the critical importance of appropriate dosage and monitoring when using methotrexate for abortion.
• Early intervention with folinic acid rescue and urine alkalization is vital for managing methotrexate macrodose toxicity.
• Further research is needed to establish clear guidelines for the use and management of high-dose methotrexate in reproductive medicine.