Intestinal endometriosis as a cause of intestinal stenosis. A case report

Endometriosis affecting the terminal ileum is a rare condition, appearing in 1-7% of women with endometriosis, with second - ary intestinal occlusion estimated in 7 -23%. Diagnosis before surgery is difficult and requires a high clinical suspicion; it should be a differential diagnosis in all women with abdominal pain. The clinical case is a 26-year-old female presented with abdominal pain and a lack of bowel movements, with poor response to medical management. A computed tomography scan shows signs suggestive of intestinal obstruction, leading to surgical treatment. A diagnostic laparoscopy was initially planned; however, due to the unavailability of the necessary equipment, a laparotomy was performed. T wo areas of stenosis were found in the terminal ileum, managed with a right hemicolectomy and ileocolic anastomosis. Pathology reports revealed endome - triotic implants in the areas of obstruction. In conclusion, while there is not established consensus regarding surgical man - agement, a minimally invasive approach is recommended when feasible. Diagnosis can be confirmed only on histopathological examination of the surgically resected specimen. The decrease in abdominal pain, gastrointestinal discom - fort, and the improvement in the quality of life are evident following surgical treatment.

Ileal endometriosis. Right hemicolectomy. Occlusion. Intestinal resection. Endometriosis. Stenosis. *Correspondence: José M. Ruvalcaba-Vallarta E-mail:  [email protected] Available onl ine: 30-05-2025 Rev Med Hosp Gen Mex. (Ahea d of print) www.hospitalgeneral.mx Date or reception: 14-08-2024 Date of acceptance: 21-10-2024 DOI: 10.24875/HGMX.24000060 0185-1063/© 2024 Sociedad Médica del Hospital General de Mexico. Published by Permanyer. This is an open access article under the CC BY -NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Endometriosis is defined as the presence of endo - metrium in an abnormal or ectopic location. Histologi - cally, it is the presence of endometrial-like tissue or glands outside the uterine cavity. It is a hormone-de - pendent gynecological disorder that is most often seen in reproductively active women 1,2. It is a common cause of pain and infertility, but it also negatively affects quality of life, intimate relationships, participation in daily activities, social activity, produc - tivity, and income 2. In their study, Fuldeore et al. report that the prevalence of diagnosed endometriosis was estimated at 6.1% (2,922 out of 48,020 women surveyed); 52.7% of women were between 18 and 29 years old when they were diagnosed with endometriosis. The majority (86.2%) of women experience symptoms before diagnosis3. In Mexico, the incidence of endometriosis in women with primary and secondary infertility diagnoses has been studied, reach- ing 34.5% in a sample of 197  patients; however, the number of fertile patients with endometriosis is unknown2. The main theories about the pathogenesis of endo - metriosis seek to explain the appearance of endometrial tissue outside the uterus. Among them are: the theory of retrograde menstruation, proposed by Sampson in 1927, suggests that during menstruation, part of the Revista Médica del Hospital General de México Revista Médica del Hospital General de México. (Ahead of print) 2 flow moves through the fallopian tubes into the perito - neal cavity, carrying with it endometrial cells that adhere and proliferate in ectopic locations. Although it explains the presence in the peritoneal cavity, it fails to justify other locations of the disease. Theory of coelomic metaplasia: states that peritoneal mesothelium cells can transform into endometrial tissue under specific hormonal or inflammatory stimuli. This could explain the presence of endometriosis in more atypical sites, such as the diaphragm, where the phenomenon of ret - rograde menstruation would not have a direct role. Theory of lymphatic and blood dissemination: It pro - poses that endometrial cells migrate through the lym - phatic system and blood circulation, which would justify the appearance of endometriosis in distant organs such as the lungs, brain, or even in the skin. Immunological theory: Suggests that a dysfunction of the immune sys - tem prevents the recognition and elimination of endo - metrial cells outside the uterus, allowing them to implant and grow. This would help to understand why some women with retrograde menstruation develop the dis - ease, whereas others do not. Theory of genetic predis - position and epigenetics: Recent studies indicate that there are genetic and environmental factors that pre - dispose some women to develop endometriosis, alter - ing the expression of certain genes and favoring the formation of lesions. Together, these theories indicate that the pathogenesis of endometriosis is complex and multifactorial, combining immunological, genetic, hor - monal, and anatomical characteristics to different degrees depending on each case 1,4-6. Endometriosis affecting the gastrointestinal tract (infiltrating deep endometriosis) has been reported in between 3% and 37% of menstruating women. It is seen in the rectum-sigmoid, cecum, small intestine, and appendix in decreasing order of frequency. Involve- ment of the ileum is quite rare, and obstruction of the small intestine is very rare. Only a few cases have been reported so far, and all required emergency surgery5,6. We present the case of a patient with intestinal endo - metriosis who presented with intestinal pseudocclusion data, requiring emergency surgery. The diagnosis of endometriosis in the ileum was made by histopathology in the resected specimen. Case presentation This is a 26-year-old female patient, with no medical or surgical history before admission, date of last period 2 weeks before, regular cycles of 28 × 4 days, active sex life with barrier contraceptive method, dys - menorrhea of more than 5 years of evolution, attended in the emergency department for the presence of abdominal pain of 2  weeks of evolution, intermittent type, located in the right iliac fossa as well as in the hypogastrium, mild-to-moderate intensity, without irra - diation to other areas and without apparent attenua - tion or aggravating factors, as the only accompanying symptom he mentioned absence of bowel movements 6 days before admission but with the presence of fla - tus, she self-medicated with oral analgesic having partial improvement, two similar previous conditions which were self-limiting. On arrival at the emergency department, she had vital signs within normal parameters, physical examina - tion with flat abdomen, slight distension, peristalsis present, decreased in frequency, pain on deep palpa - tion generalized without evidence of acute abdomen, rest without alterations. As part of the diagnostic approach, laboratory tests were requested with only an alteration in leukocytosis of 14.08 (×10 9/L) at the expense of neutrophilia 79.5%. An abdominal X-ray in two positions and an abdominal ultrasound without reporting alterations. As none of the studies were inconclusive and pain had decreased, strict medical surveillance was decided with bowel rest, defecatory surveillance, and analge - sics. 24 h later, she again presented abdominal pain, absence of bowel movements, no fever, nausea or vomiting, demotion in leukocytosis and neutrophilia, for which a tomography of the abdomen and pelvis con - trasted with the following findings: thickening of the ileal wall, maximum caliber of 44  mm, discrete striation of fat at the level of the terminal ileum at its junction with the cecum in close relation to the apparent right annex, rest unaltered. It was decided to perform diagnostic laparoscopy; however, the equipment was not available, so laparot - omy was performed, showing 12 areas of stenosis at the level of the terminal ileum, the first at 8 cm from the ileocecal junction, with an occlusion of 100% of its lumen when it rotated on its own axis, the second at 15  cm from the ileocecal junction with occlusion of approximately 60% of its lumen ( Fig. 1 ). A right hemi - colectomy was performed with mechanical ileotrans - verse anastomosis. The histopathological report of the specimen sent was: endometriosis in the muscle wall and serous wall of the ileum (transmural involvement), as well as secondary extrinsic compression in two areas, surgical edges without histological evidence of lesion (Fig. 2 ). J.M. Ruvalcaba-Vallarta et al. Intestinal endometriosis as cause of stenosis 3 Figure 1. A: the area of stenosis in the terminal ileum (white circle), found as a finding during laparotomy, is appreciated. B: specimen resulting from right hemicolectomy with a stenosis area with torsion on its own axis (white arrow). Source: authors’ own elaboration. The patient evolved favorably, tolerating a liquid diet at 24 h postoperatively and a normal diet at 36 h. The patient was discharged on the 6 th day and summoned to an outpatient clinic for the removal of stitches, finding a wound in adequate condition. 2  months later, with total remission of symptoms, she was discharged from the General Surgery Service and sent to the Gynecol - ogy Service due to histopathological diagnosis of endometriosis.

Countless hypotheses and theories have been pro - posed for the pathogenesis of endometriosis. From the implantation theory, which is currently the most widely accepted, to the stem cell theory. However, it is cur - rently still a question to be resolved1,2,5,6. Endometriosis can be asymptomatic, but it also presents a wide vari - ety of clinical manifestations, including pain, dyspareu - nia, intermittent bleeding, and infertility. The symptoms that have the greatest impact on the quality of life of patients are those associated with pain, such as dys - menorrhea, profound dyspareunia, cyclic pelvic pain, dysuria, and dyschezia, which occur cyclically accord - ing to the menstrual cycle. In addition, intestinal endo - metriosis can cause irritative functional symptoms, such as diarrhea, intestinal cramps, hematochezia, and mucus expulsion, due to the cyclic release of inflam - matory mediators, as well as obstructive mechanical symptoms, such as constipation and abdominal disten - sion, caused by enlarged nodules, intestinal angulation and stenosis, and retraction of fibrotic tissue. Some specific symptoms, such as cyclic dysphasia and tenesmus, are typical of rectal endometriosis 1,2,5-7. To date, no individual classification system ade - quately classifies endometriosis. The American Society for Reproductive Medicine’s revised criteria for staging endometriosis (revised American Society for Reproduc - tive Medicine) are the most widely used and are useful for clinicians to explain the severity of endometriosis in simple terms to patients. The ENZIAN classification describes in detail infiltrating deep endometriosis (PID) involving retroperitoneal and/or abdominal structures. BA Figure 2. A: photomicrograph shows ileum mucosa. Below in the muscular mucosa, note the presence of glands and stroma with endometrial phenotype. B: photomicrograph shows glands and endometrial stroma without atypia, immersed in smooth muscle of the intestinal muscularis propria with transmural involvement. A B Revista Médica del Hospital General de México. (Ahead of print) 4 In addition, the ENZIAN classification is probably most useful when determined using imaging modalities and can be used for surgical planning; however, it has little acceptance worldwide 1,8,9. Previously, diagnostic imaging modalities were not very successful, but new advances in the field of imag - ing show promising results for detecting intestinal lesions. In a report, Gillen et al. show that multislice tomography combined with oral contrast located 94.8% of intestinal endometriotic nodules 10. Magnetic reso - nance imaging has a high sensitivity for detecting endometriosis, but it has difficulty distinguishing it from other diseases, as well as being expensive 10-12. Ultra - sound, on the other hand, is an inexpensive and effi - cient means of examining and diagnosing intestinal endometriosis. However, diagnostic accuracy depends significantly on the sonographer’s experience 1,13. Due to the low frequency and non-specific symptoms, multiple differential diagnoses should be considered, such as tuberculous enteritis, yersinia enterocolitis, car - cinoid tumors, lymphomas, Behçet’s disease, and amoe- bomas, among others. The final diagnosis is based on histopathology and the presence of endometrial epithe - lial and stromal cells at ectopic sites 2,5,6,11-13. The quality of the available evidence on medical treatment for intestinal endometriosis is suboptimal. Most studies were not comparative. There are very few reported cases in which infiltrating deep intesti - nal endometriosis has been resolved by non-surgical management when symptoms persist or worsen, and with the disadvantage that treatment cannot be interrupted 14. Medical treatment should not be suggested if the lesion is located above the middle part of the rectum, the degree of lumen stenosis is > 60%, if the lesion infiltrates > 50% of the intestinal circumference, or if the largest diameter of the nodule is > 3  cm, the same rule is followed in the locations in the small intestine7,14-16. Surgical treatment depends on the degree of intesti - nal involvement and the clinical condition of the patient at the time of diagnosis. Ideally, it consists of intestinal resection of the affected ileal segment and primary anastomosis; however, cases have been reported in which right hemicolectomy is performed with or without anastomosis, preferring in either case the minimally invasive approach. When there is doubt of malignancy, resection with oncological criteria is justified and should be considered at the discretion of the surgeon 17-22. Although successful cases have been presented with medical management, high recurrence rates continue to be shown in contrast to patients who undergo resection, have significant and persistent long-term improvement in pelvic pain, gastrointestinal discomfort, and quality of life, as well as a negligible recurrence rate 14,23,24. Pharmacological therapy plays a fundamental role as a complement to surgical intervention, both in the pre-operative period and, more significantly, in the post-operative phase. In the pre-surgical context, its use can contribute to the reduction of the size of the lesions, thus facilitating the intervention. Subsequently, in the post-operative period, pharmacological therapy is essential to reduce the size of residual implants, control the progression of the disease in cases where surgical resection has not been able to be carried out completely, as well as to prevent the recurrence of the disease25-27. There are multiple therapeutic alternatives available for the management of endometriosis. Non-steroidal anti-inflammatory drugs are a widely used option in the treatment of chronic inflammatory diseases and have been shown to be effective in relieving primary dys - menorrhea. Combined oral contraceptives (COCs) and progestins, which are available in various presentations and routes of administration, represent the first line of hormonal treatment due to their efficacy and safety profile. In cases where these therapies are not suffi - cient, the second line is mainly composed of gonado - tropin-releasing hormone agonists. Although these agents have shown positive results in women who do not respond to COCs or progestins, it is important to mention that they require the addition of complemen - tary treatments. On the other hand, the use of danazol has decreased significantly due to the availability of hormonal options with a superior safety profile and better tolerability. Since there are few data available on the long-term efficacy and safety of aromatase inhibi - tors, they should be given only to women with symp - toms refractory to other conventional therapies in a clinical research setting 26,28-31. Studies have shown that Vitamin C and Vitamin E supplementation is effective in reducing the severity of dysmenorrhea and improving dyspareunia, as well as decreasing the intensity of pelvic pain in patients with endometriosis 32-34.

Endometriosis with terminal ileum involvement is a rare and difficult to diagnose entity that can mimic mul - tiple entities. This pathology should be suspected in all women of childbearing age who show intestinal J.M. Ruvalcaba-Vallarta et al. Intestinal endometriosis as cause of stenosis 5 symptoms without apparent causes traditionally demon- strable as if it were a functional digestive disorder, especially because of the implications that emergency surgery can have. Minimally invasive surgery should be considered the standard of management due to its widely demonstrated benefits, as well as a follow-up in conjunction with the gynecology service. Acknowledgments The authors would like to thank the pathology service of the Hospital General Agustin O’Horan, as well as all those who collaborated in the management of the patient. Funding The authors declare that they have not received funding. Conflicts of interest The authors declare no conflicts of interest. Ethical considerations Protection of humans and animals. The authors declare that no experiments involving humans or ani - mals were conducted for this research. Confidentiality, informed consent, and ethical approval. The authors have followed their institution’s confidentiality protocols, obtained informed consent from patients, and received approval from the Ethics Committee. The SAGER guidelines were followed according to the nature of the study. Declaration on the use of artificial intelligence. The authors declare that no generative artificial intelli - gence was used in the writing of this manuscript.

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