title: The characterization of bronchoalveolar lavage fluid in very elderly patients with cerebrovascular disease.
abstract: BACKGROUND
  Elderly patients with cerebrovascular disease have a high frequency of pneumonia due to impaired immune function and the occurrence of micro-aspiration.
  
  
  METHODS
  We performed bronchoalveolar lavage in 11 very elderly subjects with cerebrovascular disease and 9 healthy volunteers to investigate whether there were changes of local immunity in the lungs of the elderly subjects. The total cell count, the cell characteristics, and the lymphocyte subsets in bronchoalveolar lavage fluid were compared between the two groups.
  
  
  RESULTS
  A significant increase in the total cell count as well as in the number of neutrophils and CD8(+) T cells was observed in the elderly group. In addition, the mean CD4/CD8 lymphocyte ratio was lower in the elderly patients than in the healthy volunteers.
  
  
  CONCLUSIONS
  These observations suggest that silent micro-aspiration occurs in many elderly individuals with cerebrovascular disease and that pulmonary defenses decrease with age.
authors.affiliation: Department of Geriatric Medicine, Tokyo Medical University, Japan. kikawada@tokyo-med.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Kikawada
authors.forename: T
authors.initials: T
authors.lastname: Oyama
authors.forename: K
authors.initials: K
authors.lastname: Ogawa
authors.forename: H
authors.initials: H
authors.lastname: Arai
authors.forename: T
authors.initials: T
authors.lastname: Iwamoto
authors.forename: M
authors.initials: M
authors.lastname: Takasaki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D016516:CD4-CD8 Ratio; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology; D002452:Cell Count; D002561:Cerebrovascular Disorders / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007958:Leukocyte Count; D018655:Lymphocyte Count; D008297:Male; D009504:Neutrophils / Q000473:pathology; D012016:Reference Values