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Development and Assessment of Intracellular Infection Models for Staphylococcus aureus
Published on: January 17, 2025
Increased mortality with accessory gene regulator (agr) dysfunction in Staphylococcus aureus among bacteremic
Marin L Schweizer1, Jon P Furuno, George Sakoulas
1Iowa City VAMC, 601 Highway 6 West, Iowa City, IA 52246-2208, USA. marin-schweizer@uiowa.edu
Antimicrobial Agents and Chemotherapy
|December 22, 2010
Summary
Accessory gene regulator (agr) dysfunction in Staphylococcus aureus is linked to increased mortality in severely ill patients. This finding may help predict outcomes and guide antibiotic treatment for S. aureus bacteremia.
Area of Science:
- Microbiology
- Infectious Diseases
- Clinical Medicine
Background:
- Accessory gene regulator (agr) dysfunction in Staphylococcus aureus is associated with prolonged bacteremia.
- Understanding the impact of agr dysfunction on mortality is crucial for patient outcomes.
Purpose of the Study:
- To evaluate the independent association between agr dysfunction in S. aureus bacteremia and 30-day in-hospital mortality.
- To explore the utility of the δ-hemolysin assay for predicting patient prognosis.
Main Methods:
- Retrospective cohort study of adult inpatients with S. aureus bacteremia (2003-2007).
- Agr dysfunction identified via δ-hemolysin production assay.
- Cox proportional hazard models used to assess mortality risk, adjusting for covariates.
Main Results:
- 181 of 814 (22%) patients had S. aureus with agr dysfunction.
- Mortality was 18% in the agr dysfunction group versus 12% in the functional agr group (P=0.03).
- Agr dysfunction significantly increased mortality in severely ill patients (highest APS scores >28; adjusted HR, 1.82).
Conclusions:
- Agr dysfunction in S. aureus is an independent predictor of mortality in severely ill patients.
- The δ-hemolysin assay offers a simple, cost-effective method for predicting outcomes in S. aureus bacteremia.
- Findings may inform optimized antibiotic strategies for S. aureus infections.
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