Features of aggressive Crohn's disease:
(1) penetrating disease
(2) hospitalization for flares or disease complications
(3) multiple extraintestinal manifestations
(4) need for surgery
(5) poor response to optimal therapy
Risk factors for aggressive Crohn's disease:
(1)
early onset (age < 40 years)
(2) perianal disease
(3) stenotic disease
(4) involvement of the upper gastrointestinal tract
(5) need for corticosteroid therapy during the first flare-up
(6) absence of mucosal healing after induction of a clinical remission
(7) smoking
(8) presence of epithelioid granulomas in histologic sections
(9) elevated titers of anti-Saccharomyces cervisiae antibody (ASCA), antibody to glagellin expressed by Clostridial phylum (CBir1), antibody to the outer membrane porine of E. coli (OmpC)
(10) genetic mutations in NOD2/CARD15, ATG16L1, MDR1 genes