Clindamycin but not Intravenous Immunoglobulins reduces mortality in a retrospective cohort of critically ill patients with bacteremic Group A Streptococcal infections

OBJECTIVES: Mortality of patients requiring Intensive Care Unit (ICU) admission for an invasive group A streptococcal (GAS) infection continues being high. In critically ill patients with bacteremic GAS infection we aimed at determining risk factors for mortality. PATIENTS AND METHODS: Retrospective multicentre study carried out in nine ICU in Southern Spain. All adult patients admitted to the participant ICUs from January 2014 to June 2019 with one positive blood culture for S. pyogenes were included in this study. Patient characteristics, infection-related variables, therapeutic interventions, failure of organs, and outcomes were registered. Risk factors independently associated with ICU and in-hospital mortalities were determined by multivariate regression analyses. RESULTS: Fifty-seven patients were included: median age was 63 (45-73) years, median SOFA score at admission was 11 (7-13). The most frequent source was skin and soft tissue infection (n=32) followed by unknown origin of bacteremia (n=12). In the multivariate analysis, age (OR 1.079; 95% CI 1.016-1.145), SOFA score (OR 2.129; 95% CI 1.339-3.383) were the risk factors for ICU mortality and the use of clindamycin was identified as a protective factor (OR 0.049; 95% CI 0.003-0.737). Age and SOFA were the independent factors associated with hospital mortality however the use of clindamycin showed a strong trend but without reaching statistical significance (OR 0.085; 95% CI 0.007-1.095). CONCLUSION: In this cohort of critically ill patients the use of intravenous immunoglobulin was not identified as a protective factor for ICU or hospital mortality treatment with clindamycin significantly reduced mortality after controlling for confounders.