Endometriosis Mimicking Symptoms of Microperforation in a Teenage Girl With Inflammatory Bowel Disease

Crohn disease (CD) and ulcerative colitis (UC) are intestinal inflammatory conditions increasingly diagnosed in childhood. Complications include local abdominal and more systemic problems; however, the link to the underlying inflammatory bowel disease (IBD) is not always evident. Conversely, however, not all abdominal symptomatology in a patient with IBD is necessarily the result of the condition itself. We report on a teenage girl previously diagnosed as having UC, who presented with cyclic episodes of peritoneal symptoms initially attributed to potential microperforations from misdiagnosed CD. Laparoscopic examination and specimen confirmed diagnosis of serosal endometriosis. A teenage girl was hospitalized 3 times during a 9-month period for recurrent episodes of severe, sudden-onset abdominal pain with peritoneal signs (Table 1). Her medical history was significant for a diagnosis of IBD in summer 2007, at 14 years old. Colonoscopy had revealed pancolitis with relative rectal sparing and a normal terminal ileum. She was diagnosed as having UC based on histology and serologic markers, and responded to prednisone followed by 6-mercaptopurine. Within 5 months of diagnosis, she had her first menstruation.TABLE 1: Summary of hospital admissions (initial diagnosis of inflammatory bowel disease, summer 2007)The patient was hospitalized when she presented 1 year later with fever, periumbilical pain, vomiting, abdominal tenderness, and guarding. (Table 1). She developed Bacteroides fragilis bacteremia, attributed to intestinal microperforation, and was managed with intravenous (IV) antibiotics. One month later, she returned with similar, although less severe, abdominal pain. She was again managed conservatively. A magnetic resonance enterography revealed a tubular, chronically inflamed sigmoid colon. Four months later, the patient was again hospitalized for vomiting, severe abdominal pain, and constipation, and responded to IV antibiotics and corticosteroids. In early 2009, colonoscopy demonstrated mild chronic colitis with normal ileum; however, upper endoscopy was normal. A capsule endoscopy revealed a normal small bowel. Because history revealed irregular menses and dysmenorrhea, the patient was referred to gynecology for evaluation of possible endometriosis. Two months subsequently, the patient was readmitted with severe abdominal pain, vomiting, and peritoneal signs at the time of expected menses. Management included IV antibiotics and addition of oral contraceptive pill (OCP) for possible endometriosis. She was later switched to continuous OCP after 2 episodes of abdominal pain and vomiting were noted to accompany withdrawal bleeds. A repeat magnetic resonance imaging (MRI) of the pelvis, done while asymptomatic, did not suggest endometriosis, or any significant bowel wall thickening. In August 2009, diagnostic laparoscopy revealed normal ovaries and absence of signs of endometrial implants. Several omental adhesions were noted on the appendix and in the right lower quadrant extending to the cecum. An appendectomy was performed for suspicion of chronic/recurrent appendicitis. The appendiceal surgical specimen revealed a focus of serosal endometriosis with adhesions (Fig. 1). A diagnosis of appendiceal endometriosis was made. The patient was, thereafter, maintained on continuous OCP, with no further cyclical crises occurring between August 2009 and October 2010 (18th birthday).FIGURE 1: Serosal views of the appendix (August 2009). A, Low-power view and B, high-power view: histology demonstrating endometrial glands and stroma within the serosa of the appendix. Gross appearance of specimen described as consistent with chronic or recurrent acute appendicitis.DISCUSSION The case highlights the importance of considering non–IBD-related diagnoses in patients with IBD, particularly when the clinical presentation is unusual. Although rectal-sparing pancolitis UC is a well recognized entity in new-onset, untreated UC in children (1), the diagnosis was called into question after recurrent episodes of peritoneal signs and a B fragilis bacteremia. As a consequence, several ancillary tests were performed to search for penetrating CD: cross-sectional imaging, repeat endoscopies, and capsule endoscopy, all failing to provide evidence of CD. In retrospect, as B fragilis is part of the normal vaginal flora, its finding may not necessarily implicate a bowel source. In addition to being the most prominent organism in the lumen of the human colon, B fragilis is found in the vaginal tract of approximately 60% of women (2). It is known to be implicated in numerous gynecological conditions such as pelvic inflammatory disease and puerperal infections. As our patient was never shown to have transmural gastrointestinal tract inflammation, it is likely that the bacteremia was a result of either an inflamed appendix or genitourinary tract in the context of ectopic endometrial tissue disrupting surrounding structures at the time of expected menses. Endometriosis is a condition of menstruating females characterized by the presence of endometrial glands and stroma outside the uterus. It has increasingly been recognized as an adolescent phenomenon, with reports of diagnosis even among premenarchal girls (3). Endometriosis is most commonly seen within the pelvic cavity, but may affect more distant tissues. The incidence of gastrointestinal endometriosis varies between 3% and 37% of all cases and is more commonly found in structures closer to the uterus: the rectosigmoid (50%–90% of cases), recto-vaginal cul-de-sac (10%–20%), cecum (2%–5%), appendix (3%–18%), and small bowel (2%–16%) (4). Bowel endometriosis may present with nonspecific symptoms including diarrhea, constipation, and bloating, and sometimes cyclic pelvic or abdominal pain episodes coinciding with menses. In adolescents, it may present as chronic nonmenstrual pelvic pain or acyclic episodic pain (3). It may also present more acutely with symptoms of small or large bowel obstruction or peritoneal signs. Appendiceal endometriosis may be asymptomatic or present as acute appendicitis. Radiologic examination for endometriosis includes ultrasonography, contrast studies, and MRI. Endoscopy rarely identifies endometrial implants as the disease is usually submucosal or serosal. MRI frequently confirms the diagnosis, but the gold standard remains laparoscopic examination (5). Traditionally, IBD and endometriosis have not been believed to be linked in any way, although there are publications highlighting how the 2 pathologies may mimic one another, or be present within the same person (6,7). Nevertheless, a recent Danish study assessing the risk of future IBD in a cohort of women with endometriosis suggested there may be an increased risk, reflecting common immunologic features or as an effect of endometriosis treatment with OCP (8). In our case, the patient was diagnosed as having IBD before onset of first menses and diagnosis of endometriosis, and hence, treatment of the latter could not have caused the former. To date, there is no known association between pediatric-onset IBD and endometriosis. Pediatric IBD and endometriosis have been known to mimic each other and may both present within the same patient. Treating physicians must remain vigilant to consider endometriosis as a possibility in girls with IBD presenting with recurrent peritoneal signs.