title: Discrimination between Legionnaires' Disease and Pneumococcal Pneumonia Based on the Clinical and Laboratory Features: A Quantitative Approach Using the Modified Winthrop-University Hospital Weighted Point System.
abstract: Objective Legionnaires' disease (LD) is a common form of lobar pneumonia, but the optimum diagnostic modality has long been a subject of debate due to incomplete sensitivity and specificity. A delay in the initiation of specific therapy for LD is associated with increased mortality. The decision to treat a patient for Legionella must be made quickly. The purpose of this study was to evaluate the ability of the modified Winthrop-University Hospital WUH system to identify LD while discriminating against pneumococcal pneumonia at the time of hospitalization for community-acquired pneumonia. Methods Five patients with LD and 13 patients with pneumococcal pneumonia were retrospectively analyzed. Results The WUH system identified 4 of 5 patients with LD (sensitivity, 80%) while excluding legionellosis in 12 of 13 patients with pneumococcal pneumonia (specificity, 92%). The positive and negative likelihood ratios were 10.4 and 0.2. The area under the receiver operating characteristic curve was 0.969. Conclusion The WUH system is useful for obtaining a rapid presumptive clinical diagnosis of LD. Further investigation with a larger number of patients is strongly recommended.
authors.affiliation: Infectious Disease and Hospital Epidemiology, Kagoshima Seikyou Hospital, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamakuchi
authors.forename: Yohei
authors.initials: Y
authors.lastname: Hamada
authors.forename: Tosiharu
authors.initials: T
authors.lastname: Urakami
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Aoki
mesh_terms: D000328:Adult; D000368:Aged; D017714:Community-Acquired Infections / Q000175:diagnosis; D003937:Diagnosis, Differential; D005260:Female; D006760:Hospitalization; D006785:Hospitals, University; D006801:Humans; D007877:Legionnaires' Disease / Q000150:complications / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011018:Pneumonia, Pneumococcal / Q000150:complications / Q000175:diagnosis*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity