Endocrine Abstracts

Introduction: Gestational trophoblastic disease (GTD) is a group of disorders arising from abnormal proliferation of placental trophoblasts. Hydatiform mole (molar pregnancy) is a premalignant condition which is further devided in to partial and complete mole. Incidence of molar pregnancy is estimated to be 1 in 1000 pregnancies. Hyperthyroidism is one of the rare complications of molar pregnancy which, if not detected and treated, can lead to adverse consequences. We describe the case of a 42-year old lady, who presented to the hospital at a gestational age of 10 weeks.

Case History: Her symptoms at presentation included vaginal spotting and palpitations of 5 days onset. The background included hypertension following her last pregnancy, on treatment with labetalol 200 mg, pre-eclampsia, two previous spontaneous miscarriages, four spontaneous vaginal deliveries. At the time of assessment, pulse rate was 95/min, and the blood pressure 185/118 mmHg up to 199/123mmHg. The electrocardiogram showed sinus rythm. An ultrasound scan showed large multicystic/haemorragic lesion measuring 82 x 110 x 66mm within the endometrium in keeping with a complete molar pregnancy. The blood tests showed: thyroid stimulating hormone (TSH) of <0.01 munit/l (Range: 0.3-4.2nunit/l), Free thyroxine of >100pmol/l (Range: 12-22pmol/l), Free T3 of 28.6pmol/l (Range: 3.1-6.8pmol/l), b-chorionic gonadotrophin (b-HCG) levels 553,445units/l, alanine aminotransferase 47units/l, aspartate aminotransferase 41units/l. The urine was positive (++) for protein. Burch-Wartofsky score was 20, making thyroid strom less likely. Given the clinical picture of mild thyrotoxicosis she was started on carbimazole 60 mg daily, and continued on Labetalol 200 mg three times per day. She underwent surgical removal of molar pregnancy with uneventful post-operative course. One week later she was weaned off carbimazole. Histology confirmed the diagnosis of molar pregnancy, and her thyroid function test (TSH: <0.01munit/l, FT4: 11.7pmol/l) with bHCG levels (573 units/l) normalised two weeks later. Following discharge, the results of the thyroid receptor antibodies (<0.4 units/l) were made available, and confirmed the diagnosis.

Discussion: The clinical and biochemical picture of this patient were compatible with GTD, on the background of molar pregnancy. The sinus tachycardia was likely related with the early onset of pre-eclampsia. Careful clinical assessment is required to ensure the clinical signs are correctly interpreted prior to the surgery, as thyroid storm can easily be triggered in the context of an incorrect diagnosis. Surgical removal of mole is the definitive treatment in these cases. HCG and thyroid function test should be monitored afterwards to ensure gestational trophoblastic neoplasia doesn’t develop.