Procalcitonin in Crohn's disease with fever episodes, a variable to differentiate intra-abdominal abscess from disease flares.

BACKGROUND: Crohn's Disease (CD) is a chronic inflammatory disease accompanied by many complications, such as intra-abdominal abscess (IAA). A frequent problem in CD is the discrimination of fever caused by exacerbated bowel inflammation or IAA.

METHODS: A total of 80 CD patients complaining with fever episodes were included prospectively. PCT, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell count (WBC) were evaluated on admission. IAA was identified based on image studies and response to antibiotic therapy by physicians blind to the serum PCT level. At last, correlation between serum PCT level and patients' disease activity was also investigated.

RESULTS: Sixteen patients were identified with IAA, which showed significantly higher serum PCT level when compared with those patients who have no IAA (0.505 ng/ml vs 0.112 ng/ml, p < 0.01). PCT is a better biomarker of IAA in CD patients compared with CRP, ESR and WBC (AUC = 0.954, 0.757, 0.771 and 0.554, respectively). And the cutoff value for PCT in differentiating patients with and without IAA was 0.35 ng/ml. Correlation between serum PCT level and CDAI score (r = 0.575) was weaker than that of CRP and ESR (r = 0.628 and 0.634 respectively), but stronger than that of WBC (r = 0.162).

CONCLUSION: PCT can be an additional marker for detecting IAA in CD patients with fever episodes, and may serve as a new serological marker of disease activity.