Risk Factor Evaluation for Methicillin-Resistant Staphylococcus aureus and Pseudomonas aeruginosa in Community-Acquired Pneumonia

Abstract

Background: The 2019 community-acquired pneumonia guidelines recommend using recent respiratory cultures and locally validated epidemiology plus risk factor assessment to determine empirical coverage of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. Objective: To develop a methodology for evaluating local epidemiology and validating local risk factors for P aeruginosa and MRSA. Methods: This multicenter, retrospective cohort evaluated adult patients admitted for pneumonia. Risk factors for MRSA and P aeruginosa were evaluated using multivariable logistic regression and reported as adjusted odds ratios (aORs). Results: There were 10 723 cases evaluated. Lung abscess/empyema had the highest odds associated with MRSA (aOR = 4.24; P < 0.0001), followed by influenza (aOR = 2.34; P = 0.01), end-stage renal disease (ESRD; aOR = 2.09; P = 0.006), illicit substance use (aOR = 1.7; P = 0.007), and chronic obstructive pulmonary disease (COPD; aOR = 1.26; P = 0.04). For P aeruginosa, the highest odds were in bronchiectasis (aOR = 6.13; P < 0.0001), lung abscess/empyema (aOR = 3.36; P = 0.005), and COPD (aOR = 1.84; P < 0.0001). Isolated COPD without other risk factors did not pose an increased risk of either organism. Conclusion and Relevance: Influenza, ESRD, lung abscess/empyema, and illicit substance use were local risk factors for MRSA. Bronchiectasis and lung abscess/empyema were risk factors for Pseudomonas. COPD was associated with MRSA and Pseudomonas. However, isolated COPD had similar rates of MRSA and Pseudomonas pneumonia compared with the total population. This study established a feasible methodology for evaluating local risk factors.

Multimicrobial Pneumonia during the Early Stages of a Global Pandemic

“…Influenza, end-stage renal disease, Chronic Obstructive Pulmonary Disease (COPD), lung abscess, and illicit drug use are risk factors for MRSA. Bronchiectasis, COPD, and lung abscess are risk factors for Pseudomonas [5]. Our patient came from a nursing home; however "health care-associated pneumonia" is an outdated term, and that nomenclature is no longer used.…”

A targeted likelihood estimation comparing cefepime and piperacillin/tazobactam in critically ill patients with community-acquired pneumonia (CAP)

“…On the other hand, the wide usage of vancomycin is striking, causing some authors to propose using narrow-spectrum antimicrobials 35 . Additionally, the MRSA prevalence in CAP is less than 4% 36 , 37 .…”

Prospective profile of bacterial pathogens in hospitalized adult patients with community-acquired pneumonia: insights from multiplex real-time PCR and traditional culture techniques

“…K.pneumoniae was found by multiplex real-time PCR and traditional culture techniques at high rates (18.5% and 13.5%), followed by A. baumannii (17.3% and 12.9%) (Tables 2 and 3). Gram-negative bacilli, especially K. pneumoniae and A. and outcomes [2], [13], [18], [24], [28]- [32], especially severe CAP with COPD, older age, and regular oral corticosteroid therapy [30]- [33].…”