Artigo de pneumonia

Note: Large images and tables on this page may necessitate printing in landscape mode.

Copyright © The McGraw-Hill Companies. All rights reserved.

Harrison's Online > Chapter 251. Pneumonia > | DefinitionPneumonia is an infection of the pulmonary parenchyma. Despite being the cause of significant morbidity and mortality, pneumonia is often misdiagnosed, mistreated, and underestimated. In the past, pneumonia was typically classified as community-acquired, hospital-acquired, or ventilator-associated. Over the last decade or two, however, patients presenting to the hospital have often been found to be infected with multidrug-resistant (MDR) pathogens previously associated with hospital-acquired pneumonia. Factors responsible for this phenomenon include the development and widespread use of potent oral antibiotics, earlier transfer of patients out of acute-care hospitals to their homes or various lower-acuity facilities, increased use of outpatient IV antibiotic therapy, general aging of the population, and more extensive immunomodulatory therapies. The potential involvement of these MDR pathogens has led to a revised classification system in which infection is categorized as either community-acquired pneumonia (CAP) or health care–associated pneumonia (HCAP), with subcategories of HCAP including hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP). The conditions associated with HCAP and the likely pathogens are listed in Table 251-1. Table 251-1 Clinical Conditions Associated with and Likely Pathogens in Health Care–Associated Pneumonia | | | Pathogen | Condition | MRSA | Pseudomonas aeruginosa | Acinetobacterspp. | MDR Enterobacteriaceae | Hospitalization for 48 h | X | X | X | X | Hospitalization for 2 days in prior 3 months | X | X | X | X | Nursing home or extended-care facility residence | X | X | X | X | Antibiotic therapy in preceding 3 months | | X | | X | Chronic dialysis | X | | | |