Hospital-acquired pneumonia (non COVID-19)

Most cases of hospital-acquired pneumonia (HAP) are caused by bacteria, especially aerobic gram-negative bacilli, such as Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Acinetobacter species.

Patients usually present with a combination of fever (or hypothermia), leukocytosis (or leukopenia), purulent sputum, and poor oxygenation. A new and/or persistent alveolar shadowing on chest x-ray or computed tomography scan confirms the diagnosis.

A sputum (or other non-invasive respiratory) sample should be obtained before initiating antibiotics; the result of the culture should be used to de-escalate antibiotics and focus on the offending pathogen.

Intravenous broad-spectrum antimicrobials should be used initially for patients with severe symptoms/signs or at higher risk of resistance.

Hospital-acquired pneumonia (HAP) is an acute lower respiratory tract infection that is by definition acquired after at least 48 hours of admission to hospital and is not incubating at the time of admission.[1]Kalil AC, Metersky ML, Klompas M, et al. Management of adults with hospital-acquired and ventilator-associated pneumonia: 2016 clinical practice guidelines by the Infectious Diseases Society of America and the American Thoracic Society. Clin Infect Dis. 2016;63:e61-e111. http://cid.oxfordjournals.org/content/63/5/e61.long http://www.ncbi.nlm.nih.gov/pubmed/27418577?tool=bestpractice.com  

During the COVID-19 pandemic, for patients with suspected or confirmed COVID-19 viral pneumonia with symptoms and signs that start at any point after hospital admission, see our topic Coronavirus disease 2019 (COVID-19) . Consider all patients with cough, fever, or other suggestive symptoms to have COVID-19 until proven otherwise. Pneumonia due to COVID-19 is not covered in this topic. 

For patients with symptoms and signs consistent with bacterial pneumonia (not secondary to COVID-19) that start on days 1 or 2 after hospital admission, see our topic Community-acquired pneumonia (non-Covid-19). Non-hospitalised patients with pneumonia who have had significant experience with the healthcare system (formerly defined as having healthcare-associated pneumonia) should be managed as for community-acquired pneumonia, using local epidemiology and validated risk factors for MRSA or P aeruginosa to guide treatment decisions.[2]Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019 Oct 1;200(7):e45-e67. https://www.doi.org/10.1164/rccm.201908-1581ST http://www.ncbi.nlm.nih.gov/pubmed/31573350?tool=bestpractice.com

For patients with suspected pneumonia of any cause developing after endotracheal intubation, consult a senior specialist in critical care. Ventilator-associated pneumonia is not covered in this topic.