Transient hyperthyroidism in a woman with hydatidiform mole: a case report on unusual clinical presentation and management

Background: Hydatidiform mole (HM) is a genetically abnormal conception involving abnormal growth of placental trophoblast. HM is sometimes accompanied by hyperthyroidism, a rare but potentially life-threatening complication requiring early detection and management. This study aimed to report a case of a woman with HM complicated by transient hyperthyroidism, as well as to analyze some possible pharmacological management before the evacuation of molar tissue. Case Presentation: A 45-year-old female was referred to Dr. Soetomo Hospital Surabaya with a chief complaint of vaginal bleeding, accompanied by nausea, vomiting, frequent heart palpitations, and hand tremors. The patient had been previously diagnosed with molar pregnancy but refused to undergo curettage. At presentation, physical examination suggested incompatible uterus size with the gestational age, and the vaginal toucher indicated non-palpable ballottement. Vesicles were observed in vaginal discharge. Laboratory findings revealed elevated β-HCG, decreased thyroid stimulating hormone (TSH), and increased free thyroxine (FT4) levels. Abdominal ultrasound exhibited the presence of uterine fibroid and a honeycomb appearance. The patient was then diagnosed with molar pregnancy accompanied by hyperthyroidism; however, Burch-Warsofsky’s (BW) score (25) suggested no thyroid crisis. Before undergoing suction curettage to evacuate the hydatidiform mole, the patient received perioperative treatment for thyrotoxicosis control using methimazole, propranolol, and dexamethasone. After the surgery, hCG levels were regularly followed up until the normal range was reached. Conclusion: Despite its rarity, hyperthyroidism might become a deadly complication in molar pregnancy. Perioperative treatment to stabilize thyroid levels is prominent to prevent a thyroid storm. Treatment choice depends on the time available for preoperative preparation, the severity of the thyrotoxicosis, and the impact of any current or previous therapies. However, β-blockers should always be used unless absolutely contraindicated. Follow-up of hCG level post-operatively is critical to identify a possible occurrence of gestational trophoblastic neoplasia (GTN).