Treatment recommendations for “healthcare-associated pneumonia” (HCAP) were introduced in the 2005 American Thoracic Society / Infectious Disease Society of America (ATA/IDSA) guideline on the management of adults with pneumonia (1). HCAP was defined as pneumonia occurring in any patient who was hospitalized in an acute care hospital for two or more days within 90 days of the infection; resided in a nursing home or long-term care facility; received recent intravenous antibiotic therapy, chemotherapy, or wound care within the past 30 days of the current infection; or attended a hospital or hemodialysis clinic. The concern was that pneumonia obtained from such a setting was more likely to be caused by a drug resistant pathogen, and that this historical feature was an indication for more broad spectrum antibiotics. Over the years, however, it was shown to be overly sensitive, and more recent guidelines from the same societies (2) have eliminated it as category of pneumonia. While progress is good, a side effect of changing guidelines is that once these terms are ingrained, removing them from the medical lexicon can be a monumental task.

Why mention this?

Not infrequently I still hear residents (and occasionally attending physicians) discussing whether or not their patient qualifies as having HCAP. Clearly this shows a knowledge gap, because HCAP has been removed as a category of pneumonia by the ATS and IDSA.

This must have been changed recently, right?

Unfortunately, no. The change in definition came in 2016 (3).

What are the current categories of pneumonia?

• Community-Acquired Pneumonia (CAP): any pneumonia acquired outside of a hospital
• Hospital-Acquired Pneumonia (HAP): pneumonia that developed after 48 hours of a hospital admission
• Ventilator-Associated Pneumonia (VAP): pneumonia that developed while a patient is on a ventilator

By definition, as ED providers, we don’t see HAP nor VAP.

What difference does it make that they have removed HCAP as a category of pneumonia?

The tangible effect of changing the definitions is that there is no longer the recommendation to empirically choose antibiotics that cover MRSA and Pseudomonas (“Vanc and Zosyn,” anyone?) based solely on historical features such as a recent hospitalization or the fact that the patient lives in a nursing home or gets dialysis, etc.

What are the treatment recommendations for admitted patients with community acquired pneumonia?

• Combination therapy (beta-lactam + macrolide):
  • ampicillin/sulbactam 1.5-3 g q 6 hr
  • cefotaxime 1-2 g q 8 hr
  • ceftriaxone 1-2 g daily
  • ceftaroline 600 mg q 12 hr
    • plus
  • azithromycin 500 mg daily
  • clarithromycin 500 mg q 12 hr

• Monotherapy with a respiratory fluoroquinolone:
  • levofloxacin 750 mg daily
  • moxifloxacin 400 mg daily

These recommendations are the same whether the patient meets criteria for severe disease or not. The only times MRSA coverage (vancomycin or linezolid) or Pseudomonas coverage (pipercillin/tazobactam, cefepime, ceftazidime, imipenem, meropenem, or aztreonam) are recommended empirically are in patients with severe pneumonia with prior respiratory cultures positive for those organisms or those who have been hospitalized and received IV antibiotics in the past 90 days. Even in those cases, they recommend strategies for early deescalation.

What scoring system defines “severe” community acquired pneumonia?

This guideline uses the “2007 IDSA/ATS criteria for severe CAP” to make that determination. It has 2 major and 9 minor and requires 1 major or 3 minor for the designation of severe pneumonia.

*Of note, the guideline mentions the Pneumonia Severity Index (PSI) and CURB-65 scores, and recommends they be used to support admission vs discharge decisions but not to grade severity of an admitted patient nor to make decisions about the level of care the patient requires. They specifically state that the prefer PSI over the CURB-65.

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Summary

HCAP has not been recognized as a clinical entity since 2016. With only a very few exceptions, every patient we see in the ED with pneumonia can be treated without covering for MRSA and Pseudomonas.

This also serves as a classic example of a time when a term or concept gets into the lexicon and stays there long after it’s usefulness has passed. Times change. Research evolves. Guidelines come and go. It’s important to keep up or we look back and realize we are practicing antiquated medicine. Also, most hospitals have antibiotic stewardship processes to reduce unnecessary use of antibiotics – especially those with MRSA and Pseudomonal coverage. This is a great place to be a steward of antibiotics and practice evidence based medicine.

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References

1. American Thoracic Society; Infectious Diseases Society of America. Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. Am J Respir Crit Care Med. 2005 Feb 15;171(4):388-416. doi: 10.1164/rccm.200405-644ST. PMID: 15699079.
2. Metlay JP, Waterer GW, Long AC, Anzueto A, Brozek J, Crothers K, Cooley LA, Dean NC, Fine MJ, Flanders SA, Griffin MR, Metersky ML, Musher DM, Restrepo MI, Whitney CG. 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. doi: 10.1164/rccm.201908-1581ST. PMID: 31573350; PMCID: PMC6812437.
3. Kalil AC, Metersky ML, Klompas M, Muscedere J, Sweeney DA, Palmer LB, Napolitano LM, O’Grady NP, Bartlett JG, Carratalà J, El Solh AA, Ewig S, Fey PD, File TM Jr, Restrepo MI, Roberts JA, Waterer GW, Cruse P, Knight SL, Brozek JL. 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 Sep 1;63(5):e61-e111. doi: 10.1093/cid/ciw353. Epub 2016 Jul 14. Erratum in: Clin Infect Dis. 2017 May 1;64(9):1298. Erratum in: Clin Infect Dis. 2017 Oct 15;65(8):1435. Erratum in: Clin Infect Dis. 2017 Nov 29;65(12):2161. PMID: 27418577; PMCID: PMC4981759.