title: Clinical Characteristics of Legionella Pneumonia Diagnosed with Legionella Urinary Antigen Test.
abstract: OBJECTIVE
  The aim of our study was to describe the clinical characteristics of Legionella pneumonia diagnosed with a positive urinary antigen test, and factors associated with severe Legionella pneumonia were investigated.
  
  
  METHODS
  We retrospectively investigated the clinical characteristics of patients with Legionella pneumonia diagnosed at Tokai University Hospital between February 2006 and June 2012. The clinical characteristics of ICU cases and non-ICU cases were compared.
  
  
  RESULTS
  Twenty-six patients with Legionella pneumonia were identified (mean age 66.7 ± 19.3). Twenty patients were men (76.9 %). Impaired consciousness was observed in 12 patients (46.2 %), followed by gastrointestinal symptoms (38.5 %). Ten patients had severe pneumonia which required ICU admission. A case-controlled study comparing non-ICU cases and ICU cases demonstrated that cases with diabetes (OR 10.1, 95 % CI 1.1-90.5) and tachycardia (OR 10.1, 95 % CI 1.1-90.5) were significantly associated with ICU admission.
  
  
  CONCLUSIONS
  Legionella pneumonia did not always present as severe pneumonia. Extrapulmonary manifestations may be useful clues for diagnosis. Diabetic patients have not only a risk of contracting Legionella pneumonia, but also a risk of progression. Legionella pneumonia should be included in the differential diagnosis even in cases of mild to moderate pneumonia when presenting with extrapulmonary symptoms, especially in diabetic patients.
authors.affiliation: Department of Internal Medicine, Tokai University School of medicine, 143 Shimokasuya, Isehara 259-1193, Japan. upperricefield5@hotmail.com.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ueda
authors.forename: Masayuki
authors.initials: M
authors.lastname: Oki
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Yanagi
authors.forename: Hideki
authors.initials: H
authors.lastname: Ozawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takagi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D016022:Case-Control Studies; D048909:Diabetes Complications / Q000453:epidemiology; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D016952:Legionella pneumophila / Q000276:immunology*; D007877:Legionnaires' Disease / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012306:Risk; D012720:Severity of Illness Index
chemical_list: D000942:Antigens, Bacterial; D015415:Biomarkers