Community-acquired pneumonia pneumonia not seen on x-rays. However, congestive heart failure or other types of lung damage can mimic CAP on x-rays. Several tests can identify the cause of CAP. Blood cultures can isolate bacteria or fungi in the bloodstream. Sputum Gram staining and culture can also reveal the causative microorganism. In severe cases, bronchoscopy can collect fluid for culture. Special tests can be performed if an uncommon microorganism is suspected, such as urinalysis for Legionella antigen in Legionnaires' disease. CAP is treated with an antibiotic that kills the offending microorganism and by managing complications. If the causative microorganism is unidentified (often
Pneumonia severity index Pneumonia severity index The pneumonia severity index (PSI) or PORT Score is a clinical prediction rule that medical practitioners can use to calculate the probability of morbidity and mortality among patients with community acquired pneumonia. The PSI/PORT score is often used to predict the need for hospitalization in people with pneumonia. This is consistent with the conclusions stated in the original report that published the PSI/PORT score: "The prediction rule we describe accurately identifies the patients with community-acquired pneumonia who are at low risk for death and other adverse outcomes. This prediction rule may help physicians make more rational decisions