Respiratory Viruses in Nosocomial Pneumonia: An Evolving Paradigm

Abstract

Nosocomial pneumonia (NP) represents a leading cause of morbidity and mortality in hospitalized patients. Historically, clinicians have considered hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP), which comprise NP, to be essentially bacterial processes. As such, patients suspected of having either HAP or VAP are initially treated with broad-spectrum antibiotics, and few clinicians search for a possible culprit virus. Recent reports which build on earlier studies, however, indicate that viruses likely play an important role in NP. Studies employing viral diagnostics as part of the evaluation for NP indicate that common respiratory viruses can spread nosocomially and lead to HAP and VAP. Similarly, studies of the general epidemiology of respiratory viral infections, such as influenza, respiratory syncytial virus, adenovirus, and rhinovirus, confirm that these pathogens are important causes of NP, especially among immunosuppressed and pediatric patients. More importantly, these more contemporary analyses reveal that one cannot, based on clinical characteristics, distinguish a viral from a bacterial cause of NP. Additionally, viral HAP and VAP result in crude mortality rates that rival or exceed those reported in bacterial NP. Rigorous prospective, multicenter trials are needed to confirm the significance of respiratory viruses in NP, as are studies of novel therapeutics for these viral infections.

Impact of Multiplex PCR in the Therapeutic Management of Severe Bacterial Pneumonia

“…Its use as a marker of microbiological cure has therefore never been evaluated. Some preliminary study suggests, for both CAP and HAP, that viral-bacterial coinfection may have prognostic impact not only in influenza or SARS-CoV2 infections but also for other respiratory viruses [46][47][48]. Finally, the consequences of systematic screening of a viral co-infection in mPCR has not been evaluated either.…”

Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia: A Literature Review

“…Subsequently, in a recent meta-analysis, authors found that the incidence rate of VAP in patients with TBI varies widely between studies, from 21% to 60%, with higher rates of early-onset VAP episodes comparing to the late-onset VAP subtype. Moreover, in the same study there have been described several independent risk factors for VAP occurrence, such as smoking, tracheostomy, blood mass transfusion at hospital admission time, diabetes or high values of injury severity score (ISS) [ 10 ]. Another imperative and debatable factor to discuss is that some studies suggest the impact in differentiating VAP in ventilated traumatized patients with trauma-associated pneumonia (TAP), still being unclear if the same diagnostic criteria of VAP used as in non-traumatic patients would significantly change the incidence rate in this population.…”