Rupturing heterotopic pregnancy mimicking acute appendicitis.

Heterotopic pregnancy, the simultaneous existence of an intrauterine and an extrauterine pregnancy, is an extremely rare condition, with a reported incidence of 1 in 30,000 pregnancies [1]. Women who undergo assisted reproduction are at increased risk and in this group the incidence may reach 0.75% [2]. Because findings in patients with heterotopic pregnancy, including abdominal pain, adnexal masses, and peritoneal irritation signs, are usually nonspecific, and because the effects of an ectopic gestation are often “masked” by the co-existing intrauterine gestation, a missed or a delayed diagnosis is commonly the final result, and affected women have, as a result, a higher incidence of morbidity and mortality [3e5]. A 30-year-old nulliparous pregnant woman presented to the emergency department with symptoms of right lower abdominal pain, vaginal spotting, vomiting, and diarrhea. An intrauterine gestation had been confirmed at another clinic days ago. On examination, her body temperature, blood pressure, and pulse rate were normal. Abdominal examination revealed diffuse lower abdominal tenderness, with rebound tenderness in the right lower quadrant, indicative of peritonism. Laboratory tests revealed the levels of hemoglobin, white blood cell (WBC) count, and C-reactive protein (CRP) were 12.4 g/dL, 17,140/mL, and 0.42 mg/dL, respectively. At the emergency department, abdominal ultrasonography showed an intact intrauterine gestation, with a right abdominal tubular mass, creeping fat, and surrounding ascites with about 20 mL ascitic fluid, suggestive of threatened abortion and acute appendicitis. After hospitalization, she remained afebrile. A followup laboratory test showed the hemoglobin level, the WBC count,