Chapter 30 - Inflammatory bowel disease–like conditions: immune deficiencies

Abstract

Primary and secondary humoral and cellular immune deficiencies occur in both adult and pediatric populations, although primary immune deficiencies are predominantly seen in infants or young children. The relationship between immune deficiency, gastrointestinal (GI) infections, and GI inflammation is complex and reciprocal. Patients with primary or secondary immune deficiencies often have GI manifestations from microbial infections, concurrent autoimmune disorders, or immune deficiency per se. The GI presentations may mimic that in inflammatory bowel disease (IBD) The classic example is common variable immune deficiency. IBD, particularly in those treated with immunosuppressive medications, may develop secondary immune deficiencies, with a typical example being immunoglobulin (Ig) deficiency. Refractory disease course of IBD may be attributed to the immune deficiency. In clinical practice, intravenous Ig infusion has been used for the treatment of refractory IBD or refractory pouchitis with a favorable outcome. Endoscopy and histology along with serology, genetic testing, and microbiology are valuable for the differential diagnosis between primary or secondary immune deficiency, immune deficiency with superimposed infections, IBD, and immune deficiency concomitantly with underlying IBD.