Monogenic IBD

Determining a definitive diagnosis

Monogenic inflammatory bowel disease (IBD) refers to a diverse spectrum of rare genetic disorders that present with intestinal inflammation.1 Unlike patients with polygenic IBD, most patients with monogenic IBD show symptoms before age 6. Because monogenic and polygenic IBD can have indistinguishable endoscopic or histologic features, establishing accurate diagnosis via traditional methods remains a challenge.2

Comprehensive genetic testing to confirm diagnosis and optimize treatment

Genetic testing can identify patients with monogenic IBD and primary immunodeficiencies that present with IBD-like features. Isolating the genetic cause of the illness enables clinicians to choose treatment options that enhance outcomes. Mayo Clinic Laboratories offers a genetic panel that detects variants in 107 genes with established associations to monogenic IBD and primary immunodeficiencies that present with IBD-like features, but do not respond to standard IBD treatments. This includes testing for genes associated with rare diseases, such as Mediterranean Fever, with increased prevalence in certain ancestral groups.

Striving for diversity and equity in health care

Mayo Clinic Laboratories’ focus on diversity and equity in health care compels us to consider genetic factors when developing tests to minimize testing disparities.

When to consider testing

Signs that should raise suspicion of monogenic IBD and prompt testing:

  • Onset at age 6 or younger
  • The younger the patient, the higher the suspicion of a monogenic disorder
  • Up to 15% of patients with IBD presenting before age 6 may have a monogenic disorder2
  • Frequent infections
  • Overt skin manifestations (e.g., eczema, granulomas, cutaneous vasculitis)
  • Dysmorphism
  • Hair abnormalities
  • Refractory disease, or does not respond to conventional IBD treatment

Key testing

EOIBD | Early Onset Monogenic Inflammatory Bowel Disease (IBD) Gene Panel, Varies

  • Helpful for children with early-onset IBD, which typically occurs in children under age 6.
  • Identifies genetic variants in 107 genes with known associations to IBD and immunodeficiency.
  • Can help establish diagnosis and, in some cases, support appropriate management and surveillance for disease features based on the involved gene.
  • Includes testing for genes associated with rare diseases, such as Mediterranean fever, that are more prevalent in certain ancestral groups.

Comprehensive analysis of IBD-associated genes

Our EOIBD panel includes 107 genes linked to all major categories of IBD. The following genes are examples of those included in our panel and not a complete list.

Early-onset IBD: Genetic testing and clinical applications

Identification of early-onset IBD may enable tailored treatment and surveillance plans. With more than 50 genes implicated in early-onset IBD, genetic testing should be included in the workup of children with IBD under the age of 6. Join Mayo Clinic for a discussion of this testing and its clinical application.

Learn more

Contextualizing patient phenotype

Because genetic testing is probabilistic in nature, variant classification and interpretation can be challenging. Guidelines with specific criteria are used to decipher results; however, professional judgment is required to determine whether a detected variant is the cause of a patient’s phenotype.

Mayo Clinic Laboratories test results are interpreted by a team of experienced laboratory directors and genetic counselors familiar with the latest literature who will classify variants detected using American College of Medical Genetics and Genomics/Association for Molecular Pathology guidelines.

The detailed reports that accompany test results contextualize findings to provide clarity on disease presence. This approach provides ordering physicians the autonomy to make a diagnosis based on patient-specific factors.

Learn more about how to order this evaluation at your institution.

References

  1. Shim, Jung. Recent advances in very early onset inflammatory bowel disease. Pediatr Gastroenterol Hepatol Nutr. 2019;21(1):41–49.
  2. Lega S, Pin A, Arrigo S, Cifaldi C, Girardelli M, et al. Diagnostic approach to monogenic inflammatory bowel disease in clinical practice: a ten-year multicentric experience. Inflamm Bowel Dis. 2019;20(20):1-8.