title: Infectious aetiologies in elderly patients hospitalised with non-pneumonic lower respiratory tract infection.
abstract: OBJECTIVE
  to identify the infectious aetiologies of non-pneumonic lower respiratory tract infections in hospitalised elderly patients, and to characterise the patients in terms of demographic, clinical and therapeutic variables.
  
  
  METHODS
  a prospective, non-interventional, purely serologically based diagnostic study.
  
  
  METHODS
  a tertiary university hospital in southern Israel.
  
  
  METHODS
  133 elderly patients hospitalised for non-pneumonic lower respiratory tract infections.
  
  
  METHODS
  paired sera were obtained for each of the hospitalisations and were tested using immunofluorescence or enzyme immunoassay methods to identify 13 different pathogens. Only significant changes in antibody titers or levels between the paired sera were considered diagnostic.
  
  
  RESULTS
  at least one infectious aetiology was identified in 77 patients (58%). At least one of seven viral aetiologies was identified in 52 patients (39%). A bacterial aetiology was identified in 27 patients (20%) including Streptococcus pneumoniae in 24 (18%). An atypical bacterium was found in 27 patients (20%) including Mycoplasma pneumoniae in 15 (11%) and Legionella spp. in nine (7%). More than one aetiology was found in 23 patients (17%). One hundred and twenty nine patients (96%) suffered from serious chronic co-morbidity. One hundred and twenty one patients received antibiotics during their hospitalisation, 106 (80%) with a beta-lactam and 42 (31%) with another antibiotic.
  
  
  CONCLUSIONS
  non-pneumonic lower respiratory tract infection is caused in hospitalised elderly patients by a broad spectrum of aetiological agents, primarily respiratory viruses with a significant, though lesser, prevalence of classical and atypical bacteria. Despite this distribution of aetiologies, most patients are treated with beta-lactam antibiotics. The indication for antibiotic therapy in these patients and the choice of antibiotic preparation should be addressed in further studies.
authors.affiliation: Pulmonary Unit and Geriatrics Department, Division of Internal Medicine, Soroka University Medical Center, Beer-Sheva, Israel. Lieberma@bgumail.bgu.ac.il
authors.forename: David
authors.initials: D
authors.lastname: Lieberman
authors.forename: Devora
authors.initials: D
authors.lastname: Lieberman
authors.forename: Miriam
authors.initials: M
authors.lastname: Ben-Yaakov
authors.forename: Zilia
authors.initials: Z
authors.lastname: Lazarovich
authors.forename: Bella
authors.initials: B
authors.lastname: Ohana
authors.forename: Maureen G
authors.initials: MG
authors.lastname: Friedman
authors.forename: Bella
authors.initials: B
authors.lastname: Dvoskin
authors.forename: Maija
authors.initials: M
authors.lastname: Leinonen
authors.forename: Ida
authors.initials: I
authors.lastname: Boldur
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001424:Bacterial Infections / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D004363:Drug Utilization; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007557:Israel; D007769:Lactams; D008297:Male; D012141:Respiratory Tract Infections / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*; D016896:Treatment Outcome; D014777:Virus Diseases / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology*
chemical_list: D000900:Anti-Bacterial Agents; D007769:Lactams