Background: Inflammatory bowel disease (IBD) and celiac disease (CeD) have overlapping clinical features and may share some genetic risks. Under diagnosis and treatment of a concurrent disease can lead to persistence of symptoms and increase morbidity. We aim to characterize the natural history of patients with IBD and coexistent CeD.
Methods: A retrospective case study was performed on all adult patients with IBD and CeD at our institution. A total of 447 patients were associated with the ICD-9 or ICD-10 codes for CeD and Crohn's disease (CD), or ulcerative colitis (UC). Of these, 107 patients met the diagnostic criteria for both IBD and CeD. Patient demographics, IBD location, phenotype, medication history, disease activity, CeD diagnostic methodology, and the need for hospitalizations, surgeries, and rescue corticosteroids were noted.
Results: A total of 107 patients (52.3% male) had IBD with coexistent CeD (Table 1). The majority of patients (n=69, 65.1%) were diagnosed first with IBD then CeD after a median 7.4 years (interquartile range [IQR] 1.5–12.8 years), while 28.3% (n=30) were diagnosed first with CeD then IBD after a median of 2.9 years (IQR 0.5–6.6 years). A small proportion (n=7, 6.6%) were concurrently diagnosed with IBD and CeD. The majority (n=69, 64.5%) of CeD was diagnosed based on both histology and serology. The median age of diagnosis for IBD was 29.2 years (IQR 19.7–40.0 years) and 35.0 years (24.8–49.2 years) for CeD.
The majority of patients with IBD had ulcerative colitis (UC) (77.8% extensive colitis) while 29.9% had Crohn's disease (CD) (42% ileocolonic, 75% inflammatory phenotype) (Table 2). Co-existent PSC was diagnosed in 22.4% of IBD-CeD patients (12.5% of CD, 61.6% of UC). At 5-years follow-up after initial diagnosis or initial presentation to our institution (if previously diagnosed elsewhere with IBD), 18.7% IBD-CeD had ever used biologics (50% of CD, 7.7% of UC), 30.8% had IBD-related hospitalizations (50% of CD, 23.3% of UC), and 38.3% had IBD-related surgeries (53.1% of CD, 31.5% of UC).
Conclusions: Patients with IBD and co-existent CeD were more likely to have had IBD diagnosed first, and those with CD compared to UC had more severe disease with a larger proportion requiring the use of biologics and in need for hospitalization or surgery.