Jan. 25, 2022
First described in the early 1960s, cryptogenic multifocal ulcerous stenosing enteritis (CMUSE) is a rare illness with unknown etiology and pathophysiology. This condition is characterized by chronic or intermittent symptoms of obstruction caused by multiple fibrous strictures and shallow ulcers of the small bowel.
Because CMUSE shares some clinical and imaging features with Crohn's disease (CD), nonsteroidal anti-inflammatory drug (NSAID)-induced enteropathy, and other more-common causes of small bowel ulcerations and stenosis, making an accurate diagnosis requires integration of clinical, endoscopy, radiology and pathology data. Seeking to gain a better understanding of CMUSE, researchers from Mayo Clinic Gastroenterology and Radiology in Rochester, Minnesota, conducted a multidisciplinary study for patients diagnosed with this illness.
The results of the study, the largest single tertiary care center experience of adults with CMUSE in North America, were published in Abdominal Radiology in 2021. In their article, the authors discuss factors that may differentiate CMUSE from other more-common causes of intestinal ulcerations and potential interventions.
Methods
According to gastroenterologist Guilherme (Gui) Piovezani Ramos, M.D., and radiologist David J. Bartlett, M.D., lead authors of the Abdominal Radiology article, the researchers reviewed electronic health records from patients seen at Mayo Clinic and diagnosed with CMUSE during a 20-year period, and they abstracted clinical data and confirmed diagnosis using published criteria.
Co-authors Shannon P. Sheedy, M.D., and Jeff L. Fidler, M.D., radiologists specializing in gastrointestinal disorders, reviewed the computerized tomography enterography (CTE) and magnetic resonance enterography (MRE) exams of patients diagnosed with CMUSE to characterize the disorder's imaging features.
Results
Overall, the researchers identified 33 patients for whom CMUSE was considered as a diagnosis during initial clinical evaluation. After excluding 21 patients who were later diagnosed with a different condition and four patients who did not meet CMUSE diagnostic criteria, the researchers identified eight patients with clinically confirmed CMUSE for the study cohort. Image review from the eight patients included analysis of nine CTEs and one MRE.
Clinical presentation and imaging characteristics
The researchers note that the most common major morphologic feature observed in all patients diagnosed with CMUSE was short, multifocal small bowel strictures measuring less than 2 cm in length with circumferential luminal narrowing and stratified hyperenhancement. Listed below are some more-detailed findings that the researchers share in their article.
- Disease location: Eight (100%) patients had strictures located in the ileum; four (50%) had strictures located in the jejunum.
- Stricture quantity: Four (50%) patients with CMUSE had 10 or more strictures; three (37.5%) had from 5 to 10 strictures.
- Endoscopic findings: Six (75%) patients had circumferential ulcers; seven (87.5%) had well-demarcated ulcers.
- The median proximal small bowel dilation was 2.95 cm (range, 2.5 to 4.1 cm).
- No patients with CMUSE presented with penetrating disease (such as abscess or fistula).
Treatment and outcomes
Overall, the researchers noted that most of the patients diagnosed with CMUSE did not respond to their first treatment and had symptoms that were refractory to surgical intervention. Additional details about treatment and outcomes include the following findings:
- Budesonide or prednisone were the most common treatments, administered in seven (87.5%) patients.
- Biologic medications were administered in three (37.5%) patients; one received vedolizumab after a partial clinical response to methotrexate; one received vedolizumab after failed treatment with both budesonide and mesalamine; and one received treatment with a combination of adalimumab and azathioprine combination therapy after experiencing an adverse event during treatment with infliximab.
- Recurrence to medical therapy (median of four months after treatment) occurred in six (85.7%) patients.
- Surgery for refractory intestinal obstruction was performed in four (50%) patients; and 50% of patients who underwent surgery experienced a postoperative recurrence of ulcerating disease.
- The three (37.5%) patients treated with endoscopic balloon dilation experienced recurrence(s) of obstructive symptoms during study follow-up.
Discussion and conclusions
The Mayo Clinic researchers note that differential diagnosis of short, multifocal small bowel strictures should always include CD, NSAID-induced enteropathy and CMUSE. According to the research team, this retrospective review demonstrated that CTE and MRE are invaluable tools in the multidisciplinary diagnostic evaluation of CMUSE.
"We know that differentiating between Crohn's disease, drug-induced enteropathy and CMUSE is challenging because of their overlapping characteristics," explains Dr. Piovezani Ramos. "Some of the characteristics and imaging features we noted in our study cohort can improve our ability to distinguish between these diagnoses. For example, enterography studies showing disease involvement in multiple long small bowel segments, especially those that are patchy and asymmetric, are more indicative of Crohn's disease. In contrast, although some CMUSE lesions may have subtle asymmetry, a higher proportion of lesions in our study subjects diagnosed with CMUSE were circumferential."
"It's also helpful to note that when we can identify penetrating disease such as a fistula, abscess or perianal disease, we can exclude a diagnosis of CMUSE and NSAID-induced enteropathy," explains Mayo Clinic gastroenterologist Joseph A. Murray, M.D., the study's corresponding author. "Disease location is another significant feature. Involvement of the colon, duodenum, stomach or esophagus, and extra-enteric complications — such as primary sclerosing cholangitis and sacroiliitis — can also serve as differentiating signs for a diagnosis of Crohn's disease. Additionally, sequela of mesenteric vein thrombosis, fibrofatty proliferation and pseudosacculations are all suggestive of Crohn's disease."
The research team acknowledges that the study has limitations, including its small sample size and retrospective design. The team is hopeful, however, that the data yielded by this investigation will increase clinicians' awareness and identification of this rare condition, and encourage additional research that focuses on therapeutic options and how to position CMUSE alongside other more-common types of inflammatory bowel disease.
For more information
Ramos GP, et al. Cryptogenic multifocal ulcerous stenosing enteritis (CMUSE): A 20-year single-center clinical and radiologic experience. Abdominal Radiology. 2021;46:3798.
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