ABSTRACT
This chapter discusses serological markers and laboratory tests used to assist in the differential diagnosis and follow up of patients with CD and UC. Inflammatory bowel diseases (IBD) are considered multifactorial and polygenic diseases, and Crohns disease (CD) and nonspecific ulcerative colitis (UC) are its most important phenotypes. The differential diagnosis of these diseases before the manifestation of initial symptoms can be a real challenge. The twenty percent of patients, including those with indeterminate colitis and colorectal disease, who present with endoscopic findings of CD and UC, are the ones in which serological markers and specific laboratory tests can be employed. The best known serological markers are antineutrophil cytoplasmic antibodies and the antibody against Saccharomyces cerevisiae, but several others have been studied and used. The advent of serological markers has provided a greater understanding of the complex pathophysiology of the disease and the connection between the innate and adaptive immune systems in IBD.
