Neumonia De La Comunidad

0025-7974/01/8002-0075/0 MEDICINE® 80: 75-87, 2001 Copyright © 2001 by Lippincott Williams & Wilkins, Inc.

Vol. 80, No. 2 Printed in U.S.A.

Community-Acquired Pneumonia
A Prospective Outpatient Study
PIERRE-YVES BOCHUD, FRANÇOIS MOSER, PHILIPPE ERARD, FRANÇOIS VERDON, JEAN-PAUL STUDER, GILBERT VILLARD, ALAIN COSENDAI, MARTINE COTTING, FREDY HEIM, JACQUELINE TISSOT, YVES STRUB, MARCPAZELLER, LAYLEE SAGHAFI, ALINE WENGER, DANIEL GERMANN, LUCAS MATTER, JACQUES BILLE, LAURENT PFISTER, AND PATRICK FRANCIOLI

Introduction Pneumonia constitutes the sixth cause of death and the first cause of infectious deaths in the United States (5). The incidence of pneumonia in community studies ranges from 2.6 to 16.8 per 1,000 adults per year (1, 7, 24, 30, 55). Most information andrecommendations for clinical practice are based on studies of hospitalized patients, who represent only 5%-16% of pneumonia cases (24, 39). Only 11 clinical studies of community pneumonia have been performed in ambulatory practice (1, 9, 10, 16, 17, 23, 36, 38, 42, 51, 55). Most of these studies have focused on etiology and provide little information about clinical outcome (9, 16, 42, 51). In addition,interpretation of the results is hampered by the small number of patients (9, 16, 51), by incomplete microbiologic documentation (17, 23, 38, 42), and especially by the absence of clear radiographic criteria (16, 36, 42, 51, 55). Understanding the outcome of community pneumonia is important because it allows physicians to evaluate the risk for potential complications and the natural history of symptomresolution. Few reports have assessed the prognosis of community-acquired pneumonia, especially in the ambulatory setting (13, 22, 23). The purpose of this prospective study is to establish the etiology, clinical and radiographic characteristics, and prognosis of community pneumonia in a population of patients seeking care from practitioners on an ambulatory basis.
From Division of HospitalPreventive Medicine (PYB, LS, PF) and Division of Infectious Diseases (PYB, JB, PF), Centre Hospitalier Universitaire Vaudois, Lausanne; Institute of Microbiology (AW, JB) of Lausanne; Institute of Microbiology (DG, LM) of St. Gallen; Hospital of Cadolles (LP), Neuchâtel; and private practitioner (FM, PE, FV, JPS, GV, AC, MC, FH, JT, YS, MP), Neuchâtel, Switzerland. Part of this study was supported by aneducational grant from Pfizer. Address reprint requests to: Prof. Patrick Francioli, Division autonome de médecine préventive hospitalière, CHUV, CH-1011 Lausanne, Switzerland. Fax: 41 21 314 02 62; e-mail: Patrick.Francioli@chuv.hospvd.ch.

Patients and Methods
Potential patients were recruited consecutively during ambulatory consultation by 11 practitioners. The inclusion criteria were asfollows: 1) age over 15 years, 2) presence of recent symptoms of lower respiratory infection, 3) presence of pulmonary infiltrate on chest X-rays, and 4) patient’s consent. Patients coming from a nursing home or hospitalized during the month before the consultation were excluded from the study. The total number of patient visits during the period of the study was recorded by 5 practitioners.Patients
Case history data were recorded in a standard questionnaire for each patient, comprising age, sex, occupation, comorbidities requiring regular medical follow-up and/or chronic medication (chronic obstructive pulmonary disease, heart failure, alcoholism, diabetes mellitus) and other relevant information. The following paraclinical exams were obtained: chest X-ray, differential blood count, viruscultures from a throat swab placed in a viral transport medium (0.2 M sucrose-phosphate containing 1% bovine serum albumin, 0.1 mg gentamicin per mL, and 2.5 mg amphotericin per mL), and serum samples at 0 and 4 weeks. Sputum sample for direct examination and culture and blood cultures were obtained before the initiation of antimicrobial therapy. The patients were treated with a macrolide...