Purpose: Patients with inflammatory bowel disease (IBD) often have exacerbations. These events can be triggered by an underlying infection, which prompts the evaluation of multiple stool studies during an admission. The aim of this study was to assess the yield of stool and colonic tissue studies, and the role of repeated testing in patients with IBD who are hospitalized for an exacerbation of their disease.
Methods: We performed a retrospective cross-sectional study including patients, 18 years or older, with Crohn's disease (CD) or ulcerative colitis (UC) who were admitted to Jackson Memorial Hospital (Miami, FL) between January 2007 and January 2013 for a disease exacerbation. Variables considered were demographics, IBD phenotype, and results of the following stool studies: Clostridium difficile toxins (CDT), ova and parasites (O&P), stool cultures (SC), Cryptococcal studies, Cryptosporidium and Giardia antigen (Ag), as well as cytomegalovirus (CMV) and herpes simplex virus (HSV) stains and viral cultures (VC) from colonic tissue biopsies. Coefficients of determination were used to study the association between number of samples done and the yield for positive tests.
Results: 403 admissions for IBD exacerbations were reviewed for 192 patients. Baseline characteristics of IBD patients are shown in Table 1. Results of the yield of stool studies, and tissues stains and cultures are found in Table 2. All five patients with positive CDT were men, which was statistically significant (p=0.03). There was no association between the consecutive number of CDT samples analyzed and the yield for a positive result (r-squared=0.2, p=0.24) and 4 out of 5 of the positive CDT were done within 3 days of admission.
Conclusion: The yield for both stool and colonic tissue studies commonly used in patients admitted for an IBD exacerbation was low, especially when the test was done after 3 days of admission. Repeated testing did not demonstrate an increase in positive yield. Larger prospective cohort studies identifying those variables that can better demonstrate who will benefit from repeated stool and tissue testing are needed. Investigation into systems-based reasons for lack of execution of physician-ordered tests is warranted, with the potential for shorter hospital stays and lower health costs.