A woman with a previous right salpingectomy presents with a positive pregnancy test (hCG 3400 IU/L) and a 2.5 cm heterogeneous mass in the left adnexa on ultrasound. She is haemodynamically stable. Methotrexate (single-dose) is planned. Which finding would be a CONTRAINDICATION to medical management?
- A Serum creatinine of 180 µmol/L ✓
- B hCG level of 3400 IU/L
- C Ectopic size of 2.5 cm
- D No cardiac activity on ultrasound
Correct answer: A. Serum creatinine of 180 µmol/L
Explanation
Methotrexate is a folate antagonist excreted renally; renal impairment (creatinine >1.5 mg/dL or ~133 µmol/L) is an absolute contraindication as it leads to drug accumulation and severe toxicity. hCG <5000 IU/L, ectopic <3.5 cm without cardiac activity, and haemodynamic stability are all criteria favouring methotrexate. This patient's creatinine of 180 µmol/L (~2.0 mg/dL) exceeds the safe threshold.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.