Colonic neoplasm detection in patients with Streptococcus gallolyticus septicaemia versus average-risk individuals: a retrospective matched cohort study from a tertiary care center in Thailand

Abstract

OBJECTIVE: To compare colorectal neoplasm detection rates between patients with Streptococcus gallolyticus septicaemia and average-risk individuals undergoing screening colonoscopy and identify predictors of neoplasm detection within the septicaemia group. DESIGN: A retrospective matched cohort study SETTING: Tertiary care university hospital in Southern Thailand. PARTICIPANTS: Eighty-five patients with S. gallolyticus septicaemia and 279 average-risk individuals who underwent colonoscopy between 2014 and 2024. PRIMARY AND SECONDARY OUTCOME MEASURES: Outcomes included the polyp detection rate (PDR), adenoma detection rate (ADR), advanced adenoma detection rate (aADR) and adenocarcinoma detection rate. Logistic regression was used to estimate ORs with 95% CIs. RESULTS: In an unmatched analysis, the ADR (41.2% vs 26.9%, OR 1.90, 95% CI 1.15 to 3.16, p=0.014) and adenocarcinoma detection rate (12.9% vs 2.9%, OR 5.04, 95% CI 1.95 to 12.97, p<0.001) were significantly higher in the septicaemia group, whereas the PDR and aADR were not significantly different. In the age- and sex-matched analysis (n=50 pairs), detection rates were comparable, except for a lower PDR in the septicaemia group (44% vs 70%, OR 0.34, 95% CI 0.14 to 0.76, p=0.008). Subgroup analysis within the septicaemia group identified older age (adjusted OR 1.04 per year, 95% CI 1.01 to 1.08, p=0.023) and diabetes mellitus (adjusted OR 2.79, 95% CI 1.15 to 6.81, p=0.034) as independent predictors of colonic neoplasm detection. Importantly, colonoscopy performed after the septicaemia episode was independently associated with a markedly higher likelihood of neoplasm detection than procedures done before septicaemia (adjusted OR 4.88, 95% CI 1.70 to 14.05, p=0.002), indicating that repeat colonoscopy may be warranted even in patients who had undergone the procedure within the previous 6 months. CONCLUSIONS: S. gallolyticus septicaemia was linked to higher adenoma and adenocarcinoma detection rates, with age and diabetes mellitus further increasing such risk. Even patients who underwent colonoscopy within 6 months before septicaemia benefited from repeat colonoscopy, supporting its consideration to prevent missed or rapidly developing lesions.