Epidemiology and risk factors for mortality among methicillin-resistant Staphylococcus aureus bacteremic patients in Southern Brazil

This study aimed to evaluate the epidemiology and 30-day mortality of adult patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. We retrospectively reviewed the demographic and clinical data of adult patients with S. aureus bloodstream infections (BSI), admitted to a tertiary public teaching medical center in Porto Alegre, Southern Brazil, from January 2014 to December 2019. A total of 928 patients with S. aureus BSI were identified in the study period (68.5 per 100,000 patient-years), and the proportion of MRSA isolates was 22% (19–27%). Thus, 199 patients were included in the analyses. The median age was 62 (IQR: 51–74) years, Charlson Comorbidity Index (CCI) median was 5 (IQR: 3–6), the Pitt bacteremia score (PBS) median was 1 (IQR: 1–4), and the most common site of infection was skin and soft tissue (26%). Most infections were hospital-acquired (54%), empirical anti-MRSA treatment was initiated in 34% of the cases, and in 44% vancomycin minimum inhibitory concentration was 1.5mg/L or above. Sixty-two (31.2%) patients died up to 30 days after the bacteremia episode. Patients with more comorbid conditions (higher CCI; aOR 1.222, p = 0.006) and a more severe presentation (higher PBS; aOR 1.726, p<0.001) were independently associated with mortality. Empiric antimicrobial therapy with an anti-MRSA regimen was associated with reduced mortality (aOR 0.319, p = 0.016). Our study identified significant risk factors for 30-day mortality in patients with MRSA BSI in a population with a high incidence of S. aureus bacteremia. Empiric treatment with an anti-MRSA drug was a protective factor. No significant variation in the incidence of S. aureus BSI was recorded throughout the period.

[1]  M. Loeb,et al.  Staphylococcus aureus bacteremia mortality: A systematic review and meta-analysis. , 2022, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[2]  M. Charlson,et al.  Charlson Comorbidity Index: A Critical Review of Clinimetric Properties , 2022, Psychotherapy and Psychosomatics.

[3]  C. Sprung,et al.  Surviving sepsis campaign: international guidelines for management of sepsis and septic shock 2021 , 2021, Intensive Care Medicine.

[4]  L. C. Romero,et al.  Insights into the epidemiology of community-associated methicillin-resistant Staphylococcus aureus in special populations and at the community-healthcare interface , 2021, The Brazilian journal of infectious diseases : an official publication of the Brazilian Society of Infectious Diseases.

[5]  M. Holmes,et al.  Epidemiology, evolution and cryptic susceptibility of methicillin-resistant Staphylococcus aureus in China: a whole-genome-based survey. , 2021, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[6]  P. Bispo,et al.  Community-genotype methicillin-resistant Staphylococcus aureus skin and soft tissue infections in Latin America: a systematic review , 2021, The Brazilian journal of infectious diseases : an official publication of the Brazilian Society of Infectious Diseases.

[7]  P. d’Azevedo,et al.  Resistance profile to antimicrobials agents in methicillin-resistant Staphylococcus aureus isolated from hospitals in South Brazil between 2014-2019 , 2020, Revista da Sociedade Brasileira de Medicina Tropical.

[8]  F. Zervou,et al.  Defining the Breakpoint Duration of Staphylococcus aureus Bacteremia Predictive of Poor Outcomes. , 2020, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[9]  L. Baddour,et al.  Resilience of the Pitt Bacteremia Score: Three Decades and Counting. , 2020, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[10]  W. Kern,et al.  Burden of bacterial bloodstream infection - A brief update on epidemiology and significance of multidrug-resistant pathogens. , 2019, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[11]  L. Baddour,et al.  Resilience of the Pitt Bacteremia Score: 3 Decades and Counting. , 2019, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[12]  Robin Patel,et al.  Lack of correlation of virulence gene profiles of Staphylococcus aureus bacteremia isolates with mortality. , 2019, Microbial pathogenesis.

[13]  Ronald N. Jones,et al.  The Microbiology of Bloodstream Infection: 20-Year Trends from the SENTRY Antimicrobial Surveillance Program , 2019, Antimicrobial Agents and Chemotherapy.

[14]  J. Thaden,et al.  Changing Characteristics of Staphylococcus aureus Bacteremia: Results From a 21-Year, Prospective, Longitudinal Study. , 2019, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[15]  Rosemary C. She,et al.  Defining the Breakpoint Duration of Staphylococcus aureus Bacteremia Predictive of Poor Outcomes. , 2019, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[16]  S. Monecke,et al.  A novel multidrug-resistant PVL-negative CC1-MRSA-IV clone emerging in Ireland and Germany likely originated in South-Eastern Europe. , 2019, Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases.

[17]  M. Hellmich,et al.  Survival following Staphylococcus aureus bloodstream infection: A prospective multinational cohort study assessing the impact of place of care. , 2018, The Journal of infection.

[18]  Sahreena S. Lakhundi,et al.  Methicillin-Resistant Staphylococcus aureus: Molecular Characterization, Evolution, and Epidemiology , 2018, Clinical Microbiology Reviews.

[19]  J. Shu,et al.  Risk factors of treatment failure and 30-day mortality in patients with bacteremia due to MRSA with reduced vancomycin susceptibility , 2018, Scientific Reports.

[20]  O. Weiland,et al.  Staphylococcus aureus bacteraemia and endocarditis – epidemiology and outcome: a review , 2018, Infectious diseases.

[21]  P. Linden,et al.  Incidence, prevalence, and management of MRSA bacteremia across patient populations—a review of recent developments in MRSA management and treatment , 2017, Critical Care.

[22]  M. Dowzicky,et al.  Antimicrobial susceptibility among Gram-positive and Gram-negative organisms collected from the Latin American region between 2004 and 2015 as part of the Tigecycline Evaluation and Surveillance Trial , 2017, Annals of Clinical Microbiology and Antimicrobials.

[23]  Samuel M Brown,et al.  Physician Variation in Time to Antimicrobial Treatment for Septic Patients Presenting to the Emergency Department , 2017, Critical care medicine.

[24]  D. Falci,et al.  Absence of Correlation Between Vancomycin Consumption and Minimum Inhibitory Concentration of Methicillin-Resistant Staphylococcus aureus Isolates , 2017, Infection Control &#x0026; Hospital Epidemiology.

[25]  Vance G. Fowler,et al.  Staphylococcus aureus Infections: Epidemiology, Pathophysiology, Clinical Manifestations, and Management , 2015, Clinical Microbiology Reviews.

[26]  A. Costa-Pereira,et al.  Classification of healthcare-associated infection: a systematic review 10 years after the first proposal , 2014, BMC Medicine.

[27]  S. V. van Hal,et al.  Predictors of Mortality in Staphylococcus aureus Bacteremia , 2012, Clinical Microbiology Reviews.

[28]  A. Marra,et al.  Nosocomial Bloodstream Infections in Brazilian Hospitals: Analysis of 2,563 Cases from a Prospective Nationwide Surveillance Study , 2011, Journal of Clinical Microbiology.

[29]  Daniel J Sexton,et al.  Health CareAssociated Bloodstream Infections in Adults: A Reason To Change the Accepted Definition of Community-Acquired Infections , 2002, Annals of Internal Medicine.

[30]  C. Arias,et al.  Staphylococcus aureus bloodstream infections in Latin America: results of a multinational prospective cohort study , 2018, The Journal of antimicrobial chemotherapy.