Despite advances in the treatment of patients with lung abscess, overall mortality remains high, ranging from 10% in uncomplicated cases to as high as 75% in the presence of cancer, immunosuppression, altered consciousness, anaemia, and pneumonia (including Pseudomonas aeruginosa, Staphylococcus aureus, or Klebsiella pneumoniae).[9]Pohlson EC, McNamara JJ, Char C, et al. Lung abscess: a changing pattern of disease. Am J Surg. 1985 Jul;150(1):97-101.
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[10]Walters J, Foley N, Molyneux M. Continuing education in anaesthesia, critical care and pain: pus in the thorax: management of empyema and lung abscess. 2011 Dec 1;11(6):229-33.
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[18]Hirshberg B, Sklair-Levi M, Nir-Paz R, et al. Factors predicting mortality of patients with lung abscess. Chest. 1999 Mar;115(3):746-50.
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The presence of adverse underlying conditions and the virulence of the responsible pathogen are the principal factors determining an adverse clinical outcome.[4]Mwandumba HC, Beeching NJ. Pyogenic lung infections: factors for predicting clinical outcome of lung abscess and thoracic empyema. Curr Opin Pulm Med. 2000 May;6(3):234-9.
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Factors associated with increased mortality include the presence of an underlying condition, such as pneumonia, a neoplasm, or altered consciousness; anaemia (haemoglobin <100 g/L [<10 g/dL]); and infections with Staphylococcus aureus, Pseudomonas aeruginosa, or Klebsiella pneumoniae infection. Larger lung abscesses and those located in the right lower lobe are also associated with higher mortality.[18]Hirshberg B, Sklair-Levi M, Nir-Paz R, et al. Factors predicting mortality of patients with lung abscess. Chest. 1999 Mar;115(3):746-50.
http://www.ncbi.nlm.nih.gov/pubmed/10084487?tool=bestpractice.com
Host factors associated with poor prognosis include advanced age, debilitation, malnutrition, symptom duration >8 weeks, and immunosuppression (e.g., HIV infection).[4]Mwandumba HC, Beeching NJ. Pyogenic lung infections: factors for predicting clinical outcome of lung abscess and thoracic empyema. Curr Opin Pulm Med. 2000 May;6(3):234-9.
http://www.ncbi.nlm.nih.gov/pubmed/10782709?tool=bestpractice.com
[65]Furman AC, Jacobs F, Sepkowitz KA. Lung abscess in patients with AIDS. Clin Infect Dis. 1996 Jan;22(1):81-5.
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