New testing guidelines for community-acquired pneumonia

Abstract

Purpose of reviewThe purpose of this article is to review diagnostic testing recommendations outlined in the current American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) community-acquired pneumonia (CAP) guideline and the 2021 ATS guideline for noninfluenza respiratory viruses. Recent findingsDiagnostic testing in CAP with gram stain, lower respiratory and blood cultures, Streptococcal and Legionella urinary antigens are not routinely recommended unless identified as severe CAP or with risk factors for Methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa infection. Influenza virus testing remains a strong recommendation during periods of community viral spread. An additional 2021 ATS clinical practice guideline reviewed the use of molecular testing for noninfluenza viral pathogens in adults with suspected CAP and recommended testing in those hospitalized with severe CAP and/or various immunocompromising conditions. SummaryDiagnostic testing remains an important component of confirming and treating CAP. The CAP guideline includes recommendations surrounding diagnostic testing with lower respiratory gram stain and culture, blood cultures, Legionella and Pneumococcal urinary antigen, influenza viral testing and serum procalcitonin.There is a strong recommendation to obtain influenza virus testing during periods of community spread. However, the use of other diagnostics such as gram stain, lower respiratory and blood culture, and urinary antigen testing are dependent on severity of illness and whether a patient has been identified as having strong risk factors for MRSA or P. aeruginosa infection. The 2021 ATS clinical practice document did not routinely recommend testing noninfluenza respiratory viruses unless identified as having severe CAP and/or various immunocompromising conditions.

Early differentiated CD28+ CD27+ T lymphocytes as a biomarker for short and long-term outcomes in older patients with pneumonia

“…By contrast, the main strength is that all of these potential biomarkers were available at admission. The study design was based on routine clinical practice, which is highly relevant given that most older patients are empirically treated without obtaining a microbiologic diagnosis 34 . Consequently, the early differentiated CD28 + CD27 + T cell count could be a useful biomarker to identify older patients at higher risk of adverse outcomes.…”

Viral Pneumonia: From Influenza to COVID-19

“…It also recommended testing for respiratory viruses other than influenza virus in hospitalized patients with severe CAP or immunocompromised patients (neutropenia, active cancer therapy, history of solid-organ or blood component transplantation, advanced HIV disease, chronic use of immunosuppressive medications). 90,113,142 The use of NAATs is recommend over an influenza antigen test. 142 For the detection of SARS-CoV-2, molecular tests such as RT-PCR method or multiplex PCR are recommended.…”

Legionnaires’ Disease: Update on Diagnosis and Treatment

“…In this regard, American and European guidelines advise the use of a UAT for Legionnaires' disease only for adults with severe CAP or in patients with risk factors, such as recent travel or a link to a Legionella outbreak. In contrast, other guidelines recommend Legionella UAT for all patients admitted with CAP [ 42 , 43 ]. An important drawback of UAT is the occurrence of non-specific signals, possibly due to the presence in urine of immunocomplexes that interact with the test and give false positive results [ 44 , 45 ].…”