Impact of methicillin resistance on mortality inStaphylococcus aureusVAP: a systematic review

Abstract

The aim of the present study was to estimate the impact of methicillin resistance on mortality in ventilator-associated pneumonia (VAP) due to Staphylococcus aureus.PubMed, Scopus and the bibliographies of the eligible studies were searched. The DerSimonian-Laird random effects model was used to determine the effect of methicillin resistance on mortality.Eight articles were included. Crude in-hospital mortality was higher in patients with VAP due to methicillin-resistant S. aureus (MRSA) than in those with VAP due to methicillin-sensitive S. aureus (MSSA). This was also the case for crude intensive care unit mortality. However, three of the selected studies, which adjusted for potential confounding factors, including adequacy of empirical treatment and severity of illness, demonstrated no difference in in-hospital mortality between patients with MRSA and MSSA VAP. This was not the case for another eligible study that also made adjustment, but for confounders other than those shown above.The limited available evidence seems to suggest that methicillin resistance is associated with death among persons acquiring Staphylococcus aureus ventilator-associated pneumonia. However, although supported by even more limited data, adjustment for risk factors suggests that this association may not be causal, but probably due to confounders, such as the adequacy of empirical treatment and severity of illness.

Anti-Alpha-Hemolysin Monoclonal Antibodies Mediate Protection againstStaphylococcus aureusPneumonia

“…This is particularly notable in association with influenza infection, where concomitant staphylococcal pneumonia is often a lethal complication (7,8,12). Up to one-half of staphylococcal pneumonia isolates are classified as methicillin (meticillin)-resistant S. aureus (MRSA), confounding the delivery of appropriate treatment and resulting in reported mortality as high as 56% (1,17,24). The combination of an increasing disease burden and declining potency of traditional antimicrobials to combat S. aureus pneumonia heightens the need for novel prophylactic and therapeutic strategies.…”

Differences in hospital- and ventilator-associated pneumonia due to Staphylococcus aureus (methicillin-susceptible and methicillin-resistant) between Europe and Latin America: A comparison of the EUVAP and LATINVAP study cohorts

“…In a systematic review, Falagas and collaborators 14,15 confirmed that both in-hospital and ICU mortality of patients with VAP due to S. aureus had higher rate of methicillin-resistant strains (MRSA). Moreover, the EPIC II study confirmed these findings in a sub-analysis of MRSA episodes.…”

Infections caused by multi-drug resistant organisms are not associated with overall, all-cause mortality in the surgical intensive care unit: A 20,000 foot view

“…They conclude MRSA VAP has been associated with higher mortality in the past, however, adjustment for risk factors reveals this association may not be causal since it disappears when adjusted for confounders. (16) While many of these studies did not find significant differences in mortality, even without matching, a number of studies did. Aloush and colleagues (17) found cases of multi-drugresistant P. aeruginosa were significantly more likely to be transferred from another institution, have previous antibiotic exposure, have been in the ICU, have a foley catheter, central venous catheter, mechanical ventilation, be bedridden, and have vasopressor therapy.…”

“…Controversy exists regarding the attributable mortality due to a multitude of studies with conflicting data studying MDRO. While many studies have not demonstrated a significant association between resistant pathogens and mortality (11)(12)(13)(14)(15)(16), many do conclude resistance is independently associated with increased mortality. (17)(18)(19)(20)(21)(22)(23)(24) Quite a few of these reports have serious limitations due to small sample size, lack of a control group, failure to distinguish infections from colonization, analysis of multiple pathogens collectively, and a complete lack of adjustment for confounders of outcomes including severity of disease, comorbidities, ventilation status, and the use of invasive procedures or devices.…”