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The HCAP Handicap

The current guidelines do not specifically comment on the optimal duration of HCAP therapy or the assessment of HCAP patients not responding to therapy, likely because these areas have not been studied. Regardless, there is ever increasing support for shortening the duration of antibiotic therapies in clinically responding patients regardless of the subset of nosocomial pneumonia. As such, the duration of therapy should likely be closer to seven days than the conventional 14- to 21-day courses of therapy. In the absence of evidence to the contrary, the 2005 guidelines imply that the evaluation of HCAP patients who are not responding to therapy should be the same as for patients with other nosocomial pneumonias not responding to antibiotic therapy.

Although only briefly addressed in the guidelines, the importance of incorporating local microbiologic data cannot be overemphasized. Just as antimicrobial sensitivities vary within institutions, there is likely to be comparable variability between settings in which each subset of HCAP patients comes into contact with the healthcare system.27,28 Although, ideally, every long-term care facility would have its own, frequently updated, antibiogram, this is not feasible either logistically or financially. Due to these limitations, hospital antibiograms are typically employed as a surrogate whenever these patients are hospitalized. Given the similarity of HCAP pathogens to nosocomial organisms, individualized intensive care unit-specific antibiograms will likely better reflect the resistant pathogens of highest concern when prescribing empiric therapy.22,27,28

The implication of the severity of illness in prescribing initial antibiotic therapy is another poorly studied and controversial topic. Because HCAP likely includes a broad spectrum of potential pathogens—both community-acquired and nosocomial—it has been proposed that the presenting severity of illness may be a surrogate marker for the etiologic organisms. This philosophy proposes that less severely ill patients are more likely to have community-acquired organisms that may be successfully treated with more narrow spectrum agents, while those with a higher severity of illness are more likely to have nosocomial pathogens that should be empirically given broad spectrum agents. This topic is not addressed by the current ATS-IDSA guidelines.


The ATS-IDSA nosocomial pneumonia guidelines’ recent definition of HCAP and the attendant recommendations regarding therapies are welcome additions for clinicians who have long struggled with how best to treat these patients. It is important to realize the limitations behind the assertions made in this important document, however. First and foremost, the knowledge base on this topic is limited, and many conclusions are based on expert opinion or extrapolation of concepts relating to other nosocomial infections. What little knowledge is available comes almost exclusively from nursing-home-acquired pneumonia. This is problematic because these studies are plagued with issues regarding their limited or poor-quality microbiologic data.

In several areas, including the need for Legionella therapy, the implications of severity of illness, and the assessment of response to therapy, the data are entirely lacking. As a result, the recommendations for hospital-acquired pneumonia are generally followed in these instances. These facts highlight the need for increased epidemiologic HCAP data to optimize antibiograms, to promote adequate empiric antibiotic therapy, to assess the obsolescence of older trials, and to investigate the similarities and differences among the heterogeneous groups of patients included in the present definition. TH

Drs. Morrow and Malesker both work at Creighton University Medical Center, Omaha, Neb.


  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. Comment in Am J Respir Crit Care Med. 2006 Jan 1;173(1):131-3; author reply 133.
  2. American Thoracic Society. Hospital-acquired pneumonia in adults: diagnosis, assessment of severity, initial antimicrobial therapy, and preventive strategies. A consensus statement, November 1995. Am J Respir Crit Care Med. 1996 May;153(5):1711-1725.
  3. Pop-Vicas AE, D’Agata EM. The rising influx of multidrug-resistant gram-negative bacilli into a tertiary care hospital. Clin Infect Dis. 2005 Jun 15;40(12):1792-1798. Epub 2005 May 6.
  4. Pop-Vicas AE. Debilitated elderly in long-term care facility (LTCF)—a major reservoir of colonization with multidrug-resistant gram-negative (MDRGN) pathogens. Paper presented at: 44th Annual Meeting of the Infectious Diseases Society of America. October 2006. Toronto, Ontario, Canada.
  5. Alvarez-Lerma F. Modification of empiric antibiotic treatment in patients with pneumonia acquired in the intensive care unit. ICU-Acquired Pneumonia Study Group. Intensive Care Med. 1996 May;22(5):387-394.
  6. Celis R, Torres A, Gatell JM, et al. Nosocomial pneumonia. A multivariate analysis of risk and prognosis. Chest. 1988 Feb;93(2):318-324.
  7. Hiramatsu K, Niederman MS. Health-care-associated pneumonia: a new therapeutic paradigm. Chest. 2005 Dec;128(6):3784-3787.
  8. Fujitani S, Yu VL. A new category – healthcare-associated pneumonia: a good idea, but problems with its execution. Eur J Clin Microbiol Infect Dis. 2006 Oct;25(10):627-631.
  9. Guay DR. Guidelines for the management of adults with health care-associated pneumonia: implications for nursing facility residents. Consult Pharm. 2006 Sep;21(9):719-725.
  10. Hutt E, Kramer AM. Evidence-based guidelines for management of nursing home-acquired pneumonia. J Fam Pract. 2002 Aug;51(8):709-716.
  11. Mylotte JM. Nursing-home acquired pneumonia. Clin Infect Dis. 2002 Nov 15;35(10):1205-1211. Epub 2002 Oct 28. Comment in Clin Infect Dis. 2003 Jul 1; 37(1):148-9; author reply 149-150.
  12. El-Solh AA, Sikka P, Ramadan F, et al. Etiology of severe pneumonia in the very elderly. Am J Respir Crit Care Med. 2001 Mar;163(3 Pt 1):645-651.
  13. El-Solh AA, Aquilina AT, Dhillon RS, et al. Impact of invasive strategy on management of antimicrobial treatment failure in institutionalized older people with severe pneumonia. Am J Respir Crit Care Med. 2002 Oct 15;166(8):1038-1043.
  14. Lim WS, Macfarlane JT. A prospective comparison of nursing home acquired pneumonia with community acquired pneumonia. Eur Respir J. 2001Aug;18(2):362-368.
  15. Patriarca PA, Weber JA, Parker RA, et al. Efficacy of influenza vaccine in nursing homes. Reduction in illness and complications during an influenza A (H3N2) epidemic. JAMA. 1985 Feb 22;253(8):1136-1139.
  16. Lee C, Loeb M, Phillips A, et al. Zanamivir use during transmission of amantadine-resistant influenza A in a nursing home. Infect Control Hosp Epidemiol. 2000 Nov;21(11):700-704.
  17. Gaynes R. Health care-associated bloodstream infections: a change in thinking. Ann Intern Med. 2002 Nov 19;137(10):850-851.
  18. Friedman ND, Kaye KS, Stout JE, et al. Healthcare-associated bloodstream infections in adults: a reason to change the accepted definition of community-acquired infections. Ann Intern Med. 2002 Nov 19;137(10):791-797.
  19. Trouillet JL, Chastre J, Vuagnat A, et al. Ventilator-associated pneumonia caused by potentially drug-resistant bacteria. Am J Respir Crit Care Med. 1998 Feb;157(2):531-539.
  20. Slinin Y, Foley RN, Collins AJ. Clinical epidemiology of pneumonia in hemodialysis patients: the USRDS waves 1, 3, and 4 study. Kidney Int. 2006 Sep;70(6):1135-1141.
  21. Muder RR. Pneumonia in residents of long-term care facilities: epidemiology, etiology, management, and prevention. Am J Med. 1998 Oct;105(4):319-330.
  22. Kollef MH, Shorr A, Tabak YP, et al. Epidemiology and outcomes of health-care-associated pneumonia: results from a large US database of culture-positive pneumonia. Chest. 2005 Dec;128(6):3854-3862. Erratum in Chest. 2006 Mar; 129(3): 831. Comment in Chest. 2005 Dec; 128(6):3784-3787; Chest. 2006 Aug; 130(2):623.
  23. Fiore AE, Butler JC, Emori TG, et al. A survey of methods used to detect nosocomial legionellosis among participants in the National Nosocomial Infections Surveillance System. Infect Control Hosp Epidemiol. 1999 Jun;20(6):412-416.
  24. Korvick J, Yu VL, Fang GD. Legionella species as hospital-acquired respiratory pathogens. Semin Respir Infect. 1987 Mar;2(1):34-47.
  25. Haley CE, Cohen ML, Halter J, et al. Nosocomial Legionnaires’ disease: a continuing common-source epidemic at Wadsworth Medical Center. Ann Intern Med. 1979 Apr;90(4):583-586.
  26. Dondero TJ Jr, Rendtorff RC, Mallison GF, et al. An outbreak of Legionnaires’ disease associated with a contaminated air-conditioning cooling tower. N Engl J Med. 1980 Feb 14;302(7):365-370.
  27. Rello J, Sa-Borges M, Correa H. Variations in etiology of ventilator-associated pneumonia across four treatment sites: implications for antimicrobial prescribing practices. Am J Respir Crit Care Med. 1999 Aug;160(2):608-613.
  28. Namias N, Samiian L, Nino D, et al. Incidence and susceptibility of pathogenic bacteria vary between intensive care units within a single hospital: implications for empiric antibiotic strategies. J Trauma. 2000 Oct;49(4):638-645.

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