The CALLY Index as a Predictive Tool for Surgical Site Infection After Pancreaticoduodenectomy: A Retrospective Cohort Study.

BACKGROUND

Surgical site infection (SSI) after pancreaticoduodenectomy (PD) remains a major cause of post-operative morbidity. Various risk factors for SSI have been identified. This study aimed to investigate the relationship between the C-reactive protein (CRP)-albumin-lymphocyte (CALLY) index, a novel inflammatory biomarker, and SSI following PD.

METHODS

The outcomes of patients who underwent PD between January 2017 and December 2022 were retrospectively analyzed. Patients who underwent laparoscopic surgery, received neoadjuvant therapy for borderline or locally advanced tumors, had metastatic disease, or presented with evident infections requiring treatment at the time of surgery were excluded. Demographic data, post-operative outcomes, and the presence of SSI were recorded. The CALLY index and other potential risk factors for SSI were evaluated.

RESULTS

The cutoff value for the CALLY index was determined as 5. Patients with a CALLY index <5 had a significantly higher incidence of SSI (p < 0.001). Multi-variate analysis demonstrated risk factors for SSI included CALLY index, elevated pre-operative CRP level, post-operative pancreatic fistula, and pre-operative biliary drainage (p = 0.021, p = 0.003, p < 0.001, and p = 0.037, respectively). Multi-variate analysis demonstrated that the CALLY index was a strong independent predictor of SSI (odds ratio = 5.195; 95% confidence interval: 2.430-11.107).

CONCLUSIONS

The CALLY index is an independent risk factor for SSI after PD. This index reflects inflammation, immune status, and nutritional condition and represents a simple, non-invasive, and easily calculable predictive tool.