care, her pulmonary status gradually returned to baseline and she was tapered off phenytoin without subsequent seizure activity. IMPLICATIONS/DISCUSSION: There are very few reports of a pulmonary embolus (PE) presenting as seizure. Given the acuity of onset of this patient's symptoms and the severity of her initial respiratory acidosis, as well as the lack of neurologic findings, we presume that her seizure represents the onset of her pulmonary embolus, though we can not definitively establish causal relationship. Clinical suspicion of PE may be compromised by the attribution of symptoms to the seizure, such as tachypnea, tachycardia, and hypoxia. The initial evaluation of seizure patients is primarily neurologic, delaying the diagnosis of a cardiopulmonary syndrome. In this particular case, the patient's medical history played a key role in the delayed diagnosis of PE, as her pulmonary symptomatology was attributed to asthma, despite the fact that she had been well controlled on minimal medication prior to admission, and that her clinical signs did not completely resolve with the treatment of her exacerbation. Furthermore, this young, active woman had low risk for thromboembolic disease, especially in the setting of a negative evaluation for hypercoaguability. She did use oral contraception, but this particular medication includes only 0.10mg levonorgestrel and 0.2mg ethinyl estradiol and the patient was a nonsmoker. Thromboembolism should therefore be considered in any patients with acute dyspnea, evidence of cerebral hypoperfusion, hypoxia, or unexplained seizure, even in the setting of pulmonary pathophysiology. year-old healthy female who presented to the emergency department after having her first seizure. She was found by her son in bed with jerking of her left upper extremity. When she regained consciousness she found that she bit her tongue and had urinary incontinence. She was well up until three days before when she developed a constant low-grade headache. Her last menstrual cycle was three months before presentation although she reports some light vaginal bleeding one week prior. Per the patient she had no sexual activity for six months. Physical exam on admission was significant for blood pressure of 145/82 and 1+ ankle edema. The neurological exam was completely normal. The patient did not know she was pregnant on admission but an initial beta-HCG was 12,700. Her urinalysis showed 3+ proteinuria. An ultrasound confirmed the presence of a 30 week gestation fetus. A head CT showed low attenuation lesions in both subcortical parietal lobes and in the left frontal lobe. The patient was transferred to Labor and Delivery with the presumptive diagnosis of eclampsia. She received intravenous magnesium sulfate and steroids to enhance fetal lung maturity. The next day after some fetal distress she delivered a viable male infant via cesarean section. Her vaginal bleeding one week prior to admission was due to placental abruption. IMPLICATIONS/DISCUSSION: Eclampsia is not commonly encountered in the practice of internal medicine but it should be considered in the evaluation of a new-onset seizure disorder in women of reproductive age. It has an incidence of approximately 5 cases per 100,000 live births. It is characterized by generalized seizures or coma in the presence of preeclampsia (hypertension, edema, proteinuria) . It is most common in nulliparous women in the teenage years and early twenties and in women over 35. More than 20% of cases occur before 30 weeks gestation, and 75% of cases occur at term or within 48 hours of delivery. It remains the second most common cause of maternal death in the United States. Treatment consists of oxygen, intravenous magnesium and antihypertensive medications. Anticonvulsant medications may be given for recurrent seizures. The fetus should be delivered promptly. Unfortunately this woman did not recognize that she was pregnant therefore she did not receive any prenatal care. This case underscores the importance of pregnancy testing in all women of reproductive age with a new-onset seizure disorder to expedite the diagnosis. Eclampsia should be part of the differential diagnosis in the evaluation of a new seizure disorder in all women of reproductive age unless she proves not to be pregnant. Early recognition and treatment of this disorder can prevent some potentially devastating consequences.