title: Bacteremic pneumococcal pneumonia: serotype distribution, antimicrobial susceptibility, severity scores, risk factors, and mortality in a single center in Chile.
abstract: OBJECTIVE
  Bacteremic pneumococcal pneumonia (BPP) is a severe condition. To evaluate seasonal distribution, mortality, serotype frequencies, antimicrobial susceptibility, and different severity scores among patients with BPP.
  
  
  METHODS
  Patients were identified by laboratory data and restricted to adulthood. Standard methods were used for serotyping and antimicrobial susceptibility. Risk factors were analyzed by univariate and multivariate methods. Severity scores (APACHE II, CURB-65 and CAP PIRO) were compared using ROC curves.
  
  
  RESULTS
  Sixty events of community-acquired BPP occurred between 2005 and 2010. A seasonal pattern was detected. Mean age was 72.1 years old (81.4% ≥ 60 years). All had a predisposing factor. Previous influenza (3.3%) or pneumococcal immunization (1.7%) was infrequent. Admission to critical units was required by 51.7%. Twenty-two serotypes were identified among 59 strains. Only one strain had intermediate resistance to penicillin (1.7%). In-hospital mortality reached 33.3%. Multivariate analysis identified a CAP PIRO score>3 (OR 29.7; IC95 4.7-187), age ≥ 65 years (OR 42.1; IC95 2.2-796), and a platelet count<100,000/μL (OR 10.9; IC95 1.2-96) as significant independent factors associated with death. ROC curve analysis did not reveal statistical differences between the three severity scores to predict death (AUC 0.77-0.90). The prognostic yield for all of them was limited (Positive Likelihood Ratio: 1.5-3.8).
  
  
  CONCLUSIONS
  BPP had a high case-fatality rate in this group of adult patients with no association to resistant isolates, and a low immunization record. Three independent factors were related to death and the prognostic yield of different severity scores was low.
authors.affiliation: Servicio de Infectología, Hospital Militar de Santiago, Chile. Electronic address: albertofica@gmail.com.
authors.forename: Alberto
authors.initials: A
authors.lastname: Fica
authors.affiliation: Unidad Coronaria, Hospital Militar de Santiago, Chile.
authors.forename: Nicolás
authors.initials: N
authors.lastname: Bunster
authors.affiliation: Unidad de Pacientes Críticos, Hospital Militar de Santiago, Chile.
authors.forename: Felipe
authors.initials: F
authors.lastname: Aliaga
authors.affiliation: Residente Medicina Interna, Hospital Militar de Santiago, Chile.
authors.forename: Felipe
authors.initials: F
authors.lastname: Olivares
authors.affiliation: Laboratorio de Microbiología, Hospital Militar de Santiago, Chile.
authors.forename: Lorena
authors.initials: L
authors.lastname: Porte
authors.affiliation: Laboratorio de Microbiología, Hospital Militar de Santiago, Chile.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Braun
authors.affiliation: Servicio de Infectología, Hospital Militar de Santiago, Chile.
authors.forename: Jeannette
authors.initials: J
authors.lastname: Dabanch
authors.affiliation: Subdepartamento de Microbiología, Instituto de Salud Pública, Chile.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Hormázabal
authors.affiliation: Unidad de Pacientes Críticos, Hospital Militar de Santiago, Chile.
authors.forename: Antonio
authors.initials: A
authors.lastname: Hernández
authors.affiliation: Servicio de Enfermedades Respiratorias, Hospital Militar de Santiago, Chile.
authors.forename: María Guacolda
authors.initials: MG
authors.lastname: Benavides
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000382:microbiology / Q000401:mortality*; D002677:Chile / Q000453:epidemiology; D017714:Community-Acquired Infections / Q000382:microbiology / Q000401:mortality; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011018:Pneumonia, Pneumococcal / Q000401:mortality*; D012621:Seasons; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents
keywords: APACHE II; Bacteremia; CURB-65; Elderly; Microbial drug resistance; Mortality; PIRO; Risk factors; Serotyping; Streptococcus pneumoniae