MRE Does Not Fare Well at Detecting Lesions Evident on Upper Endoscopy

A recent study (PC Church et al. JPGN 2018; 67: 53-8) examined how well EGD findings were detected by MRE in 188 children (mean age 14 years).

Key findings:

  • EGD was macroscopically abnormal in 93 (49%) with ulcerations being the most common abnormality in 66 (35%).
  • In contrast, the local radiologist identified UGI inflammation in 7 (4%) and the central radiologists identied UGI inflammation in 20 (22%).  “There was no agreement between local and central radiologists when examining the UGI as a whole (κ=-0.02, P-0.59)”
  • The local radiologists “correctly identified only 5 of 93 (8%) patients with UGI findings on EGD.”  The central radiologists “correctly identified 9 of 45 (30%) patients with UGI findings on EGD.”

The authors state that “the Porto criteria mandate the performance of EGD for all pediatric patients suspected of having IBD. Our study has demonstrated that MRE cannot be relied upon as the sole method of evaluating the UGI.”

My take: For those who take care of children with IBD, this study will not come as a surprise as many of the UGI findings (found at endoscopy) are subtle.  This study does quantify the much higher sensitivity of endoscopic evaluation and is similar to studies that have compared capsule endoscopy to MRE.

Related blog posts:

 

Cumberland Island 2018

ESPGHAN IBD Diagnostic Practice Recommendations -Revised Porto Criteria

Recently ESPGHAN assembled an international group of European experts in pediatric inflammatory bowel disease (PIBD) to establish practice recommendations (JPGN 2014; 58: 795-806).  Their aim was “to revise the original Porto criteria using an evidence-based approach and consensus process to yield specific practice recommendations for the diagnosis of PIBD.”

Before detailing some of their recommendations, I want to state my main criticism: these recommendations do not consider cost or cost-effectiveness. This is important since we do not live in a world where costs are irrelevant.

Some specific recommendations/observations:

1. “We recommend performing small bowel imaging in all suspected cases of IBD at diagnosis; this may be deferred in typical UC.”  In addition, all suspected cases of IBD should undergo esophagogastroduodenoscopy (EGD) and ileocolonoscopy.  “The diagnostic yield of an EGD to diagnose Crohn’s disease (CD) in patients with an otherwise normal workup [ileocolonoscopy/small bowel imaging] is ~7.5%. ”

2. The authors clarify the use of IBD-unclassified (IBD-U). “IBD-U should be …for patients with colitis and highly atypical findings.” Atypical findings for ulcerative colitis: include rectal sparing, and cecal patch (present in 2% of pediatric patients with left-sided colitis).  Table 3 suggests that if at least one “class 2” (rare feature) exists or at least 2 “class 3” (uncommon) feature exists, then labeling IBD-U is appropriate.

Rare (Class 2):

  • significant growth delay
  • histologic and gross sparing of rectum
  • transmural inflammation in the absence of severe colitis
  • duodenal or esophageal ulcers (not due to other causes)
  • multiple aphthous ulcerations in the stomach (not due to other causes)
  • positive ASCA in the presence of negative pANCA
  • mucosal inflammation more severe in proximal colon

Uncommon (Class 3):

  • severe scalloping of stomach or duodenum (not due to other causes)
  • focal chronic duodenitis (not due to other causes)
  • aphthous ulcerations in the colon

3. Crohn’s disease, according to Table 3, should be diagnosed with any of the following:

  • well-formed granulomas anywhere in the GI tract, remote from a ruptured crypt
  • deep serpentine ulcerations, cobblestoning or stenosis anywhere in the small bowel
  • fistulizing disease
  • ileal inflammation in the presence of normal cecum

4. “Normal blood tests do not exclude the diagnosis of IBD”… Fecal markers (eg. calprotectin) are “extremely sensitive in the detection of mucosal inflammation but are not specific for IBD.”

5.”Although small bowel imaging is encouraged in all of the patients with suspected IBD, it is essential in pediatric patients with CD, IBD-U, or atypical UC.”  Magnetic resonance enterography (MRE) is currently the imaging modality of choice in PIBD.  Wireless capsule endoscopy (WCE) is a “useful alternative.”  The authors advocate for imaging because it may “detect small intestinal involvement…and identify disease complications.”

6. Evaluation for primary immune deficiency should be performed in all cases of PIBD  diagnosed <2 years of age.

While the authors acknowledge that “clinical considerations may require taking a course of action that varies from these criteria,” nevertheless, they are likely to influence clinical practice.  My personal belief is that there are many situations in which small bowel imaging will not result in changes in clinical care.  Furthermore, many patients, especially younger patients, would require anesthesia in order to complete a MRE which is an added burden.  In addition, with the added emphasis on assessing response to therapy, one could envision that some patients would be better served with imaging after implementing treatment.

Related blog posts: