Severity Assessment and the Immediate and Long-Term Prognosis in Community-Acquired Pneumonia

Abstract

Severity assessment is a crucial step in the initial management of patients with community-acquired pneumonia (CAP). While approximately half of patients are at low risk of death and can be safely treated as outpatients, around 20% are at increased risk. While CURB-65 (confusion, respiratory rate, blood pressure, urea) and pneumonia severity index (PSI) scores are equally useful as an adjunct to clinical judgment to identify patients at low risk, the so-called minor American Thoracic Society/Infectious Diseases Society of America criteria are predictive of patients in need of intensified treatment (i.e., mechanical ventilation and/or vasopressor treatment). Such patients represent medical emergencies. In elderly patients, CRB-65 (confusion, respiratory rate, blood pressure, age) is no longer predictive of low risk; instead, poor functional status is the best predictor of death. In addition to scores, assessment of oxygenation and unstable comorbidity, as well as lactate and biomarkers remain important to consider. The added value of combined clinical and biomarker risk stratification strategies should be evaluated in large prospective interventional trials.Survivors of hospitalized CAP have a considerable excess long-term mortality. Risk factors include age, male gender, and nursing home residency, as well as increased PSI and CURB-65 scores. Cardiovascular, pulmonary, renal, and neoplastic comorbidities are prominent causes of long-term mortality. Comorbidities are vulnerable to both the acute and chronic subclinical inflammatory challenge delivered by pulmonary infection and are thereby drivers of mortality. Biomarkers are promising in identifying patients at increased risk of long-term mortality. Future studies should develop consistent strategies of risk stratification and intervention to improve long-term outcomes of patients with CAP.

Severity of disease and mortality for hospitalized patients with community-acquired viral pneumonia compared to patients with community-acquired bacterial pneumonia

“…Of those admitted to the hospital, 10-20% of patients are admitted to the ICU [7]. While imaging and prognosticating tools like the CURB-65 and Pneumonia Severity Index assist in the diagnosis and severity assessment of pneumonia, distinguishing between viral and bacterial pneumonia remains a challenge [8].…”

Derivation and validation of a prediction rule for mortality of patients with respiratory virus-related pneumonia (RV-p score)

“… 22 However, some studies have recently suggested that CURB-65 and PSI are insufficient for predicting mortality in patients with influenza or other viral-based pneumonia. 11 , 12 , 23 Likewise, our results suggest that these scoring methods may underestimate the mortality of patients with RV-p. In fact, 63.1% and 67.6% of the deceased patients had been classified as PSI risk class I–III and CURB-65 score 0–2, respectively, commonly regarded as low risks for death.…”

“…22 However, some studies have recently suggested that CURB-65 and PSI are insufficient for predicting mortality in patients with influenza or other viral-based pneumonia. 11,12,23 It is worth noting that PSI and CURB-65 scores are not well designed to categorize viral pneumonia cases. Indeed, patients discriminated by these scoring methods have been primarily diagnosed with standard or atypical bacterial pneumonia.…”

Clinical characteristics and predictors of pneumonia in patients presenting fever or respiratory symptoms with normal or low leukocyte counts: a retrospective study

“…With increasing age, the risk for pneumonia increased. As a previous study revealed that advanced age is one of the independent prognostic predictors of mortality in patients with CAP, [17,18] it was also associated with readmission [19].…”