Current Issues of Empirical Therapy of Severe Bacterial Community-Acquired Pneumonia During the Season of Respiratory Viral Infections

Abstract

Progredient growth of morbidity and mortality of patients with community-acquired pneumonia (CAP) requires optimization of treatment including antibacterial therapy. Implementation of molecular-genetic methods of diagnostics of viral and viral-bacterial infections in clinical practice has significantly augmented the conception of etiology of community-acquired pneumonia. Seasonal fluctuation of CAP prevalence corresponds with growth of morbidity of acute respiratory infections and influenza which contribute to the etiological structure of CAP by increasing the risk of infection caused by staphylococci. The synergy between influenza A virus and S.aureus has been shown; it is associated with an increase of virus replication in the presence of specific staphylococcal proteases and the ability of viruses to increase adhesion of S.aureusin the respiratory tract, to decrease phagocytosis of S.aureus by macrophages/neutrophils and production of antimicrobial peptides, as well as to increase the probability of secondary bacterial co-infection. Therefore, the most important requirement for the empiric therapy agents of CAP is high streptococcal and staphylococcal activity. According to the current guidelines on antimicrobial therapy of severe CAP, antipneumococcic cephalosporins, macrolides, and fluoroquinolones are the basic treatment agents, but none of them have the combined high antistaphylococcal and antipneumococcal activity inherent in ceftaroline. The advantages of ceftaroline over ceftriaxone and levofloxacin in terms of the probability of reaching target concentrations for clinically relevant pharmacokinetic/pharmacodynamic parameters are shown. Meta-analysis of randomized clinical trials showed the higher clinical efficacy of ceftaroline in comparison to ceftriaxone with similar adverse event rate. Summarized analysis of antibiotic susceptibility data, pharmacokinetic/pharmacodynamic and clinical data, as well as negative epidemiological trends confirms the necessity of optimization of antimicrobial therapy of CAP for implementation of ceftaroline advantages against pneumococci and staphylococci in comparison to other β-lactams. Therefore, empiric treatment with ceftaroline is the most rational option for the therapy of CAP in critically ill patients during the season of respiratory viral infection.