Medically managed tubal ectopic pregnancy presenting as a peritoneal loose body.

To cite: Cooke WR, Kirk E. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/ bcr-2015-211871 DESCRIPTION Peritoneal loose bodies are asymptomatic free intraperitoneal masses, typically found incidentally. Their aetiology is attributed to torsion and separation of the appendices epiploicae; histology usually shows fibrous tissue. We report a case of ectopic pregnancy with a co-incidental finding of a peritoneal loose body at the time of laparoscopy. A 30-year-old woman with a history of two previous ectopic pregnancies, both managed medically with methotrexate, presented with a positive pregnancy test and acute lower abdominal pain. A diagnosis of a right-sided ectopic pregnancy was made on transvaginal ultrasound. In view of her pain, she was treated surgically. Laparoscopy showed a 30×20×10 mm unattached cystic structure in the vesicouterine pouch (figure 1), in addition to a ruptured right ampullary ectopic pregnancy. Histologically, the cystic structure had degenerate decidua remnants at its core (figure 1). The histology suggests that the peritoneal loose body represented one of the two previous ectopic pregnancies, which had been expelled (spontaneously or as a result of methotrexate) into the peritoneal cavity. This represents the first case of a peritoneal loose body arising from a previous medically managed ectopic pregnancy. The peritoneal loose body may represent an early lithopaedion (an advanced abdominal pregnancy retained within the peritoneum, which has become calcified). Santoro et al hypothesise that abnormal fallopian contractions may lead to intraperitoneal expulsion of the embryo, resulting in lithopaedion. We propose that the peritoneal loose body described may similarly have arisen due to abnormal fallopian contractions and may have become calcified at a more advanced gestation.