Assessment of Microbiota and Their Drug Resistance in Chronic Fistulous Tracts.

BACKGROUND

Bacteria colonizing an enterocutaneous fistula tract have not been clarified. The aims of this study were to investigate the pathogen spectra of fistulous tracts and their resistance to antibiotics in patients with chronic fistulas.

METHODS

We conducted a one-year prospective single-center study. In the absence of significant sepsis, consecutively stabilized patients with chronic enterocutaneous fistula were included. Microbiology and antimicrobial susceptibility of isolates from the tracts were analyzed. The correlations between the existence of bacteria and various clinical values were investigated further.

RESULTS

Forty-one patients were enrolled, of whom eight had a negative culture. A total of 48 bacterial strains were harvested, including 42 strains of gram-negative bacteria and six strains of gram-positive bacteria, most of which were multiple-drug-resistant. The three bacteria cultured most often were Escherichia coli (11 strains; 22.9%), Pseudomonas aeruginosa (eight strains; 16.7%), and Klebsiella pneumoniae (eight strains). Binary logistic regression analysis with forward (conditional) stepwise selection found that fistula length correlated with positive bacterial results (p=0.018). Other variables, namely entire length of hospitalization and fistula duration and location, were unrelated to the presence of micro-organisms in fistula tracts.

CONCLUSIONS

Multiple-drug-resistant gram-negative bacteria were the main pathogens colonizing chronic fistula tracts. Fistula length was significantly associated with the presence of pathogens in a multivariable logistic regression model.