Prognostic value of preoperative neutrophil-to-lymphocyte ratio in Crohn’s disease

BACKGROUND: The Neutrophil-to-lymphocyte-ratio has recently gained increased attention as a prognostic marker for malignant disease and short term outcomes. There is little data available in patients with Crohn's disease, thus the present study was conducted to correlate preoperative Neutrophil-to-lymphocyte-ratio values with disease phenotype and postoperative course. METHODS: We comprised 373 patients, who underwent intestinal resection for symptomatic Crohn's disease at an academic tertiary referral centre between 2000 and 2014. Preoperative Neutrophil-to-lymphocyte-ratio values were calculated and analyzed in regard to disease phenotype and 30-day morbidity rate. All relevant data were obtained from the institutional database and individual chart review. RESULTS: Male patients had significantly higher preoperative Neutrophil-to-lymphocyte-ratio values compared to female patients (5 vs. 4; p = 0.0075). A higher Neutrophil-to-lymphocyte-ratio was also found in patients with an acute indication for surgery (6.15 vs. 4.3; p = 0.0374), presenting with abscesses (5.36 vs. 4.28; p = 0.0254), inflammatory masses (5.23 vs. 4.08; p = 0.0294) or malignancy in the resected specimen (9.06 vs. 4.35, p = 0.0231). Surprisingly, patients developing postsurgical complications showed significantly lower Neutrophil-to-lymphocyte-ratio values (3.77 vs. 4.67; p = 0.0461). CONCLUSIONS: Elevated preoperative Neutrophil-to-lymphocyte-ratio in symptomatic Crohn's disease is not predictive for complications. However, Neutrophil-to-lymphocyte-ratio showed a significant correlation with specific disease phenotypes. Most strikingly, Neutrophil-to-lymphocyte-ratio was highly elevated in patients with a colorectal cancer in the resected specimen, which needs to be addressed in future studies.