Magnetic resonance enterography: A reliable tool for detecting terminal ileal Crohn's disease

INDIA: The diagnosis of endoscopically severe, but not mild, terminal ileal Crohn's disease can be made with the help of magnetic resonance enterography, which is a credible and sensitive method, states a study published in Indian Journal of Gastroenterology.

As a chronic inflammatory bowel disease, Crohn's disease (CD) frequently necessitates repeated imaging of patients in order to identify disease activity and other consequences. Even though endoscopy is the gold standard for diagnosis, it may not be appropriate for all patients and only plays a small part in identifying profound submucosal/mesenteric illnesses and intra abdominal problems. Magnetic resonance enterography (MRE) has developed recently as a non-invasive, radiation-free imaging method for the assessment of CD patients. There are few actual data from the Indian subcontinent about the effectiveness of MRE in terminal ileal CD.

The authors looked into the correlation between ileo-colonoscopy and magnetic resonance enterography for evaluating the progression of terminal ileal Crohn's disease.

Patients with terminal ileal CD who had ileo-colonoscopy and MRE were retrospectively analyzed. Ileo-colonoscopy was regarded as the gold standard for determining the severity of an illness. A simple endoscopic score for Crohn's disease (SES-CD) of ≥2 or above on an ileo-colonoscopy was deemed active illness; the presence of ulcers signified severe disease. Using the magnetic resonance index of activity (MARIA) and the simplified MARIA (MARIAs), MRE scoring of the illness activity was carried out (MARIAs). Calculations were made to determine the degree of agreement between ileo-colonoscopy and MRE as well as the sensitivity of MRE to detect mucosal ulcerations and the comparison of MARIA and MARIAs for assessment of disease activity.

Conclusive points of the study:

• 70 terminal ileal CD patients (mean age 40.7415.56 years; 71.4% men [n=50]) were assessed.
• The MARIA and MARIAs scores had sensitivity values of 0.76 and 0.84, respectively, to identify active illness.
• For both MARIA and MARIAs, the area under the receiver operating characteristic curve (AUROC) for spotting severe disease was 0.836 (p<0.0001) and 0.861 (p<0.0001), respectively.
• There was no agreement between SES-CD and MARIA or MARIAs for mild active illness, while there was fair and moderate agreement for severe active disease for MARIA and MARIAs.
• For the detection of active and severe disease, MARIA and MARIAs performed similarly (0.759, p<0.0001 and 0.840, p<0.0001, respectively).
• MRE had a mucosal ulcer detection sensitivity of 68.18%.

For the identification of terminal ileal Crohn's disease that is endoscopically severe but not mild, magnetic resonance enterography is a reliable and sensitive method, concluded the authors.

REFERENCE

Kakkar, C., Singh, A., Mahajan, R. et al. Correlation between magnetic resonance enterography and ileo-colonoscopy for assessment of disease activity in terminal ileal Crohn's disease. Indian J Gastroenterol (2022). https://doi.org/10.1007/s12664-022-01242-7