title: Revision of the severity rating and classification of hospital-acquired pneumonia in the Japanese Respiratory Society guidelines.
abstract: OBJECTIVE
  Based on the results of a multicentre collaborative survey of hospital-acquired pneumonia (HAP) conducted in Japan, the severity rating and classification of pneumonia in the Japanese Respiratory Society guidelines for management of HAP were examined.
  
  
  METHODS
  Parameters for the severity classification were selected from the factors associated with prognosis in the HAP survey and in other previous reports. Depending on the presence of the parameters listed below, patients with HAP were stratified into those with high, moderate or low-risk. The high-risk group was defined as patients with three or more of the following risk factors: 'malignant tumour or immunocompromised status', 'impaired consciousness', 'requiring fraction of inspired oxygen (FiO(2)) > 35% to maintain SaO(2) > 90%', 'man aged 70 years or older, or woman aged 75 years or older' and 'oliguria or dehydration.' The moderate-risk group was defined as patients with any of the secondary risk factors as follows: 'CRP > or = 200 mg/L' and 'extent of infiltration on CXR covers at least 2/3 of one lung'. The low-risk group was defined as all other patients.
  
  
  RESULTS
  Application of this classification scheme to the patients enrolled in the HAP survey revealed a mortality rate of 40.8% (98/240) in the high-risk group, which was significantly higher than the mortality rates in the moderate and low-risk groups: 24.9% (69/277) and 12.1% (101/834), respectively.
  
  
  CONCLUSIONS
  These results indicate that it is possible to classify patients using these parameters as prognostic indicators.
authors.affiliation: Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Medical Sciences, Nagasaki, Japan. seki@nagasaki-u.ac.jp
authors.forename: Masafumi
authors.initials: M
authors.lastname: Seki
authors.forename: Akira
authors.initials: A
authors.lastname: Watanabe
authors.forename: Keiichi
authors.initials: K
authors.lastname: Mikasa
authors.forename: Junichi
authors.initials: J
authors.lastname: Kadota
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kohno
mesh_terms: D003428:Cross Infection / Q000145:classification*; D006801:Humans; D007564:Japan; D011014:Pneumonia / Q000145:classification*; D017410:Practice Guidelines as Topic; D011379:Prognosis; D018570:Risk Assessment / Q000145:classification; D012720:Severity of Illness Index