Serum level of TNF-alpha receptor type II better correlates with severity of Crohn's disease than other cytokines and conventional clinical activity indicators

Crohn's disease activity index (CDAI) and serum C-reactive protein (CRP) levels are not prefect indicators of Crohn's disease severity. Magnetic resonance enteroclysis (MRE) is a method allowing simultaneous assessment of lesions involving an entire intestinal wall as well as intra- and extraintestinal spaces. This method, however, is not appropriate for monitoring the course of disease and therapeutic effects.

Objective: To evaluate which of the extensive panel of pro- and anti- inflammatory cytokines correlates with an actual severity of CD assessed by MRE. MATERIAL AND METHODS. 57 patients with endoscopically diagnosed ileocecal form of CD (28 women, age 29 + 11 yrs, range 18-62 yrs) hospitalized in 2007-2008. The mean CDAI was 293 + 119 points, range 18-503 points and serum CRP level was 17.5 + 31 mg/l, range 0.1-122 mg/l. MRE was performed in each patient not later than 3 days after entry to the study. The summarized score was calculated using standardized protocol, assessing the intestine wall thickness and length of its involvement (ileocecal region), pattern of mural contrast enhancement, presence of fistulas or other extraintestinal lesions and enlargement of mesenteric lymph nodes. At admission the blood was taken to measure following cytokines: IL-la, IL-1 receptor antagonist, IL-6, soluble IL-6 receptor, TNF-alpha, TNF-alpha type II receptor and IL-10.

Results: In Spearman's correlation test the MRE score showed the strongest relationship with serum level of TNF-alpha type II receptor (r = 0.52, p < 0.001), correlating less significantly with IL-6 level (r = 0.37, p < 0.01) and CDAI (r = 0.40, p < 0.001).

Conclusions: TNFalpha receptor type II shows better correlation with the severity of ileocecal CD (assessed by MRE) than CDAI or serum levels of other cytokines and CRP.