I n a recent study, the Radford-Smith group addressed the important question of whether it was possible to identify and characterize patients with normal or low serum Creactive protein (CRP) levels in a prospective cohort of patients with active Crohn's disease (as per the criteria of the Crohn's Disease Activity Index [CDAI]). 1 Florin et al compared patients with active CD who had low CRP levels with those who had high CRP levels and found significantly more ileal localization, less pure colonic localization, and lower body mass index (BMI) in the low-CRP group. The 2 groups showed no significant differences in age at diagnosis, smoking status, rate of appendectomy, duration of disease, number of relapses, disease behaviors, or extra-intestinal manifestations. Prior to inclusion in the study, the patients in the low-CRP group had undergone CD abdominal surgical procedures significantly more often than had those in the high-CRP group because of the high frequency of ileal involvement in the low-CRP group. Because NOD2 mutations are more often associated with CD patients with ileal disease, this study examined NOD2 variants but found no significant differences in their allelic frequency between the 2 groups. Thus, patients with active disease (as per CDAI criteria) and low serum CRP would be patients with pure ileal disease.