Abstract:

Objective

To investigate the correlation of fecal bacteria，fecal calprotectin （FC），systemic immunoinflammatory index （SII），D-dimer （D-D） levels and disease severity in patients with ulcerative colitis （UC）.

Methods

A total of 115 UC patients admitted to Xijing Hospital from October 2018 to December 2019 were selected as the study objects，and they were divided into the mild group（n=46），the moderate group （n=39），and the severe group （n=30） according to the severity of the disease.The distribution of fecal bacteria，FC，SII，and D-D levels of patients in the three groups were compared，and the distribution of fecal bacteria，FC，SII and D-D levels in patients with different prognosis were compared. Pearson correlation analysis was used to analyze the correlation between fecal bacteria，FC，SII and D-D levels and disease severity and prognosis in UC patients.

Results

The levels of Enterococcus，Escherichia coli and Bacteroides in the severe UC group were higher than those in the moderate and mild UC groups； the levels of Lactobacillus and Bifidobacteria were significantly lower than those in the moderate and mild UC groups，the levels of Enterococcus，Escherichia coli and Bacteroides in the moderate UC group were higher than those in the mild UC group； the levels of Lactobacillus and Bifidobacteria in the moderate UC group were significantly lower than those in the mild UC group，with statistically significant differences （P＜0.05）； the levels of FC，SII and D-D in the severe UC group were higher than those in the moderate and mild UC groups，and the levels of FC，SII and D-D in the moderate UC group were higher than those in the mild UC group，with statistically significant differences （P＜0.05）.After 6 months of outpatient follow-up of 115 UC patients，88 cases had good prognosis and 27 cases had poor prognosis. The levels of Enterococcus，Escherichia coli，Bacteroides，FC，SII and D-D in UC patients with poor prognosis were higher than those in UC patients with good prognosis，while Lactobacillus and Bifidobacterium were significantly lower than those in UC patients with good prognosis，with statistically significant differences （P＜0.05）. The results of Pearson correlation analysis showed that the levels of Enterococcus，Escherichia coli，Bacteroides，FC，SII and D-D were positively correlated with disease severity and negatively correlated with prognosis in UC patients （P＜0.05）. The levels of Lactobacillus and Bifidobacterium were negatively correlated with disease severity and positively correlated with prognosis（P＜0.05）.

Conclusion

Significantly elevated levels of fecal bacterial dysbiosis，FC，SII，and D-D in UC patients are closely associated with disease severity，and clinical testing of these indicators can help to accurately assess the condition and treatment efficacy of UC patients.

Key words: Ulcerative colitis, Fecal bacteria, Fecal calprotectin, Systemic immune inflammatory index, D-dimer, Disease severity