Progressive and nonresolving pneumonia.

Low, Donald E; Mazzulli, Tony; Marrie, Tom

PURPOSE OF REVIEW 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. RECENT FINDINGS 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. SUMMARY 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.