Clinical and Biochemical Determinants of the Systemic Inflammation Response Index During Vancomycin Therapy.

BACKGROUND

Vancomycin (VAN) is the standard of care for Gram-positive infections. The systemic inflammation response index (SIRI) has been associated with infections and sepsis across various clinical settings; however, the correlates and determinants of the SIRI during VAN therapy remain unexplored. This retrospective cross-sectional study aimed to identify the determinants of the SIRI among adults treated with VAN.

METHODS

Medical records of 299 patients who received VAN were analyzed consecutively. Prevalence rates were calculated; Spearman's correlation and regression models were employed to evaluate associations; risk assessment was conducted using prevalence ratios and odds ratios; diagnostic potential was assessed using receiver operating characteristic curves.

RESULTS

The SIRI was significantly higher in intensive care unit (ICU) patients than in non-ICU patients receiving VAN therapy (p < 0.0001). Age, blood pressure, creatinine, Na+, CO2, albumin, aspartate transaminase (AST), gamma-glutamyl transferase (GGT), bilirubin, coefficient of variation in red cell distribution width (RDW-CV), and platelet count were significantly and differentially correlated with the SIRI. In the adjusted analysis, ICU requirement emerged as the strongest independent predictor of SIRI, with ICU patients showing a 2.13-fold higher SIRI(p < 0.0001). Moreover, the prevalence of ICU requirement was 1.61 times higher in individuals with increased SIRI (p = 0.0018), whose odds of ICU requirement were 2.16 times higher (p = 0.0016). The SIRI also demonstrated moderate discriminatory ability, with the highest performance observed in patients younger than 50 years (area under the curve [AUC] = 0.731, p = 0.0001).

CONCLUSIONS

The SIRI is a novel and cost-effective marker that is correlated with distinct demographic and clinical variables and independently associated with ICU requirement in VAN-treated patients and may aid in the risk stratification and management of this vulnerable patient cohort.