New perspectives in aspiration community acquired Pneumonia

ABSTRACT

Introduction: Aspiration pneumonia is a subclass of community-acquired pneumonia that is expected to have an increasing contribution in mortality and morbidity, particularly in the elderly population over the next coming decades. While studies have revealed significant progress in identifying risk factors for aspiration pneumonia, the clinical presentation and diagnosis remain challenging to healthcare providers.

Areas covered: We conducted a broad literature review using the MeSH heading in PubMed/MEDLINE of ‘aspiration pneumonia’ from January 1970 to July 2019. The understanding of the microbiology of aspiration pneumonia has evolved from a possible shift in the causative organisms away from anaerobes to traditional community-acquired pneumonia organisms. The importance of this shift is not yet known, but it has questioned the pathogenic role of anaerobes, appropriate anaerobic testing and the role of these pathogens in the pulmonary microbiome in patients with pneumonia. The identification of risk factors led to strategies to prevent or minimize the risk of aspiration pneumonia with moderate success.

Expert opinion: Our expert opinion is that further research is needed to determine the role of the microbiome with aspiration pneumonia and patient risk factors. There is also a great need to develop clinical tools to help providers diagnose, treat, and prevent aspiration pneumonia.

KEYWORDS:

• Aspiration
• pneumonia
• anaerobes
• microbiome
• community-acquired

Article Highlights

• Pulmonary aspiration syndromes result from aspiration of foreign material into the lungs which can cause a spectrum of syndromes including aspiration pneumonia.

• Defense mechanisms to prevent aspiration include a strong cough reflex, active mucociliary clearance mechanism, and strong immune system.

• Risk factors for aspiration pneumonia include compromised host defenses, swallowing disorders, age-related aspiration, and impaired consciousness. Prevention involves addressing and reducing these risk factors.

• Patients with aspiration pneumonia are associated with a higher mortality compared to those with non-aspiration pneumonia.

• Given the complexity and lack of risk assessment models, diagnosing and treating patients with aspiration pneumonia can be challenging for clinicians.

• Research in the interplay between the lung microbiome and the host immune system may open new avenues for research into the treatment and prevention of aspiration pneumonia.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

The content of this manuscript is solely the responsibility of the authors and does not necessarily represent the official views of the Department of Veterans Affairs.