title: Progressive and nonresolving pneumonia.
abstract: OBJECTIVE
  Patients with progressive and/or nonresolving community-acquired pneumonia are at risk for increased morbidity and mortality. It is critical to be able to identify patients at risk to institute early appropriate therapy. The purpose of this review is to summarise the most updated developments in this area.
  
  
  RESULTS
  This review will glean from the recent literature clinical, laboratory, and radiologic findings that help identify patients at risk for such complications of their pneumonia. New studies will be reviewed that have identified some of the causes for treatment failures including the type of pathogen and discordant antimicrobial therapy. It will also discuss newly recognised and emerging infectious diseases that may result in progressive or nonresponding pneumonia including severe acute respiratory syndrome, avian influenzae, severe group A streptococcal disease, and community-acquired methicillin-resistant Staphylococcus aureus. Promising treatments have been identified for patients with progressive pneumonia due to an overwhelming host immune response including activated protein C and intravenous immunoglobulin.
  
  
  CONCLUSIONS
  Both progressive and nonresolving pneumonia represent treatment failure as a result of inappropriate initial therapy, a noninfectious cause, or an overwhelming immune response. It is critical to be able to identify patients with nonresponding pneumonia and to identify patients at risk for progressive pneumonia to institute appropriate therapy.
authors.affiliation: Department of Microbiology, Toronto Medical Laboratories and Mount Sinai Hospital, Ontario, Canada. dlow@mtsinai.on.ca
authors.forename: Donald E
authors.initials: DE
authors.lastname: Low
authors.forename: Tony
authors.initials: T
authors.lastname: Mazzulli
authors.forename: Tom
authors.initials: T
authors.lastname: Marrie
mesh_terms: D000416:Alberta / Q000453:epidemiology; D000900:Anti-Bacterial Agents; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D018450:Disease Progression; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D018410:Pneumonia, Bacterial / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology*; D012720:Severity of Illness Index; D015996:Survival Rate; D017211:Treatment Failure
chemical_list: D000900:Anti-Bacterial Agents