Hyperthyroidism and Seizures during Pregnancy

ABSTRACT

Untreated hyperthyroidism during pregnancy is associated with increased maternal and perinatal morbidity. Some features of this disease simulate preeclampsia, which may encourage delivery of the fetus. We report a case of poorly controlled hyperthyroidism associated with generalized seizures, where patient management was directed at a diagnosis of preeclampsia-eclampsia. Although the presence of eclampsia and marked hyperthyroidism is very rare, this case illustrates the importance of aggressive medical management of hyperthyroidism. A 17-year-old gravida was diagnosed with hyperthyroidism at 15 weeks' gestation. At 26 weeks' gestation, she was admitted to the hospital after noting edema of the upper and lower extremities, nausea, vomiting, shortness of breath, and a cough. At admission, she was hypertensive, tachycardic, and dyspneic. The patient was believed to have preeclampsia with pulmonary edema complicated by hyperthyroidism. We initiated magnesium sulfate therapy and administered several bolus doses of hydralazine, with little effect on blood pressure. Oliguria was noted, and a pulmonary artery catheter was inserted. Hours later, generalized seizure activity occurred, and a decision was made for abdominal delivery. Postoperatively, cardiovascular function stabilized. On postoperative day 3, we received the results of the thyroid function tests obtained at admission, which suggested a markedly hyperthyroid condition. Untreated or poorly treated hyperthyroidism may present a clinical picture similar to preeclampsia. In our case, both disease processes coexisted in their severest forms. It is possible, although completely unproven, that a relationship exists between poorly controlled hyperthyroidism and preeclampsia-eclampsia. More importantly, accurate diagnosis of hyperthyroidism should lead to prompt medical or surgical management, thereby decreasing maternal and perinatal morbidity.

Keywords

Hyperthyroidism - pregnancy - perinatal morbidity - seizures