Choosing antibiotic therapy for severe community-acquired pneumonia

Community-acquired pneumonia (CAP) is known as a major worldwide health concern considering it has been shown to account for 78% of infection-related deaths in the USA. It is a common cause for hospitalization with a continued incidence rise in the elderly, high mortality rate and long-term sequelae in critically ill patients. Severe CAP (sCAP) is an accepted terminology used to describe ICU admitted patients with CAP. The aim of this review is to further report on the major advances in treatment for patients with sCAP including new antibiotic treatments despite macrolide resistance as seen in the ICU, and multifaceted antibiotic stewardship interventions that may lead to the reduction broad-spectrum antibiotic use in CAP.

We aim to examine the most recent findings in order to determine appropriate empirical antibiotic choices, timing regimens and evidence for clinical effectiveness. This will be addressed by focusing on the use combination therapies, the usefulness of severity scores and the difficulty to treat multidrug-resistant pathogens, including gram negatives such as Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus. Relevant reports referenced within included randomized controlled trials, meta-analyses, observational studies, systematic reviews and international guidelines where applicable.

New antibiotics have been recently launched with direct agent-specific properties that have been shown to avoid the overuse of previous broad-spectrum antibiotics when treating patients sCAP. Although narrow-spectrum antibiotics are now recommended and imperative in improving a patients' prognosis, there are also some considerations when prescribing antibiotics that are beyond the spectrum. There is a need to implement effective policies of de-escalation to avoid antibiotic resistance and the risk for developing subsequent infections by combining informed clinical judgement and the application of biomarkers. Reaching clinical stability and avoidance of treatment failure are the most important pillars in treatment success.