Tubal abortion masquerading as an acute appendicitis with a negative urine pregnancy test: A case report

INTRODUCTION AND IMPORTANCE: Spontaneous expulsion of product of conception through the fimbrial end to the peritoneal cavity is a rare mode of progression of tubal pregnancy. Thus, ectopic pregnancy can present with right-sided iliac fossa pain which can be preoperatively misdiagnosed as acute appendicitis. CASE HISTORY: A 30-year regularly menstruating woman presented with right iliac fossa pain which was diagnosed as acute appendicitis preoperatively with an ultrasound. However, intraoperatively, a product of conception-like material measuring 3 ∗ 3 cm was seen hanging from the right fimbrial end of the fallopian tube with a normal appendix. With an intraoperative diagnosis of spontaneous tubal abortion, histopathology of the resected mass showed chorionic villi lined by trophoblastic cells along with decidualized tissue, fibrinoid material, and blood clot. DISCUSSION: Ectopic pregnancy presenting as a right iliac fossa pain can mimic acute appendicitis. An abnormal β-hCG pattern/level which doesn't correspond to the gestational age suggests the likely diagnosis of ectopic gestation. Transvaginal ultrasound is the preferred imaging modality for the evaluation of patients with suspected ectopic gestation. A urine pregnancy kit cannot always exclude an underlying ectopic pregnancy because of the associated false-negative results. CONCLUSION: Urgent laparotomy to prevent detrimental complications associated with ectopic gestation should be done. Surgeons should be aware of this suspicion as a false negative UPT can happen and misguide clinicians about the possible occurrence of ectopic pregnancy.