Endometriosis may involve the bowel wall and cause symptoms prompting colonoscopic examination. This report describes such a condition in a patient where colonoscopy, biopsy, and diagnosis of endometriosis also led to the unexpected identification of early pregnancy.
A 34-year-old woman was referred by her gynecologist with complaints of new constipation for 3 months, pain in the lower left abdomen, rectal bleeding, and mucoid discharge. She was married, without children, and known to have a recurrent large left ovarian cyst. Colonoscopy was performed after bowel preparation with polyethylene glycol-electrolyte solution and premedication with fentanyl, atropine, and midazolam. At colonoscopy, external pressure could be felt on the rectum. The only finding was a 5-mm elevated nodule at 25 cm, which was red and covered with a blood clot, and a biopsy was taken. The pathology diagnosis was endometriosis, which was not unexpected; however decidual changes in the endometrial tissue, indicating pregnancy, were also noted (Figure [1]).
Figure 1 Photomicrograph of colonoscopic biopsy sample. The surface epithelium is normal colonic mucosa; in the submucosa there is an abrupt change in tissue histology to that of endometrium. The endometrial stromal cells have been transformed into large epithelioid cells because of continued progestational influence, indicative of decidualization (hematoxylin & eosin; original magnification × 100).
When the patient returned to receive the results, she said that she was receiving therapy to facilitate pregnancy. The patient was very happy to learn of her pregnancy and reported that there had been no untoward consequences from the endoscopic examination. As it is not usual to perform an elective colonoscopic examination during pregnancy, we also contacted the patient 1 year later and were pleased to learn that the pregnancy had been uneventful and that her baby daughter is quite normal. Elective colonoscopy during early pregnancy is only performed when the clinical indication justifies the possibly increased risk to the fetus in utero, from bowel preparation, premedication, and the procedure itself [1]. In our patient, the symptoms had led to a differential diagnosis which included neoplasia [2]. Therefore, even if we had known that she was pregnant, her recent onset of clinically significant complaints would have justified at least a minimal endoscopic examination, progressing until a lesion had been identified and biopsied.
To our knowledge, the diagnosis of pregnancy by colonoscopic biopsy of endometriosis has not previously been reported.
