Autism Spectrum Disorder (ASD) and Inflammatory Bowel Disease (IBD): Determination of a Pathophysiologic Link and Special Considerations for a Unique Patient Population

Abstract

Background: Patients with ASD commonly have gastrointestinal symptoms and those who undergo endoscopic evaluation are often found to have an underlying inflammatory process [1-2]. Because of this, there is interest in understanding a possible shared immunopathology between the neurological and GI processes in these patients. We present the cases of two such patients from our clinic experience, and discuss some unique considerations for managing these patients. Cases: Case #1 A 22 year-old woman with a history of ASD was diagnosed with Crohn's disease (CD) of the colon and perianal area in 2010. She initially received infliximab, but she did not achieve clinical remission. She has subsequently been on multiple other therapies with inadequate response. Combination therapy with adalimumab and azathioprine has resulted in clinical improvement. Unique challenges in the management of this case include strong desires to avoid surgery with ostomy and also less invasive disease monitoring with fecal calprotectin (FC). Case #2: A 23 year-old man with a history of ASD was diagnosed with CD of the colon and perianal area in 2012. Initial treatment with mesalamine and metronidazole did not achieve remission. Successful management has included adalimumab and ongoing use of mesalamine. Unique challenges in the management of this case include the patient's limitations in self-reporting symptoms as well as difficulty performing perianal exams and colonoscopies, so FC was also used. Discussion: It is shown that ASD patients with GI symptoms and IBD patients have significant overlap in mucosal gene expression [3]. In addition, patients with ASD and those with IBD share features of abnormal intestinal permeability [4] and pro-inflammatory markers. Most recently, it has been shown that patients with ASD and GI symptoms have an altered gut microflora compared to controls, with less diverse bacterial taxa. These findings support a careful evaluation for co-existent IBD in patients with ASD who have GI symptoms or lab abnormalities. It is noteworthy that both our patients have a similar CD phenotype, and the challenges to physical examination and disease monitoring require thoughtful interactions and partnering with their parents and legal guardians to provide optimal care.