Correlation of C-reactive protein with clinical and endoscopic activity in patients with ulcerative colitis.
OBJECTIVE
Evaluating disease activity is important in ulcerative colitis. Laboratory markers should be a non-invasive alternative to endoscopy for patients. The objective of our study was to scrutinize the correlation between C-reactive protein (CRP) levels and clinical and endoscopic activity in ulcerative colitis patients.


METHODS
We conducted a prospective study between January 2007 and December 2009. In the study we chose consecutive patients of our department with ulcerative colitis. All patients received a standardized questionnaire, clinical examination, and colonoscopy. Based on clinical and endoscopic data, we calculated the disease activity index (DAI) and the Rachmilewitz score.


RESULTS
One-hundred and one patients were included. At the time of inclusion, 67 patients had an active disease and 34 patients were in remission. The mean DAI was 6.9 (1-12). The mean Rachmilewitz score was 4.7 (0-12). The median CRP rate was 20.2 ± 24.5 mg/l (1-107 mg/l). An increased CRP was found in 46 patients (46%). An increased CRP level was observed in patients with active disease (P < 0.0001). The DAI was higher in patients with increased CRP (9.5 ± 1.6 vs. 4.7 ± 3.6; P < 0.0001). The Rachmilewitz score was also higher in patients with increased CRP (7.2 ± 2.3 vs. 2.7 ± 3.2; P < 0.0001). A statistically significant association was found between the CRP and the DAI (r = 0.51, P < 0.0001) and between the CRP and the Rachmilewitz score (r = 0.46, P < 0.0001). The optimum cut-off of CRP level that separates active or inactive disease was calculated to be 10 ml/l, with AUC estimated at 0.81 ± 0.04 (95%CI: 0.72-0.88), a sensitivity of 67.1 (95%CI: 54.6-78.1) and a specificity of 97% (95%CI: 84.6-99.5).


CONCLUSIONS
Levels of CRP are correlated to clinical and endoscopic activity in ulcerative colitis patients.
Department of Gastroenterology, A La Rabta Hospital, 1007 Tunis, Tunisia. sami_karoui@fastmail.fm
Sami
S
Karoui
Sonia
S
Laz
Meriem
M
Serghini
Norsaf
N
Bibani
Jalel
J
Boubaker
Azza
A
Filali
D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers; D002097:C-Reactive Protein / Q000378:metabolism*; D003093:Colitis, Ulcerative / Q000097:blood* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D055815:Young Adult
D015415:Biomarkers; D002097:C-Reactive Protein