Delay in antibiotic therapy results in fatal disease outcome in murine pneumococcal pneumonia
Sarah Berger,
Cengiz Goekeri,
Shishir K. Gupta,
Julio Vera,
Kristina Dietert,
Ulrike Behrendt,
Jasmin Lienau,
Sandra-Maria Wienhold,
Achim D. Gruber,
Norbert Suttorp,
Martin Witzenrath,
Geraldine Nouailles
Affiliations
Sarah Berger
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Cengiz Goekeri
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Shishir K. Gupta
Department of Dermatology, Laboratory of Systems Tumor Immunology, Friedrich-Alexander-Universität Erlangen-Nürnberg
Julio Vera
Department of Dermatology, Laboratory of Systems Tumor Immunology, Friedrich-Alexander-Universität Erlangen-Nürnberg
Kristina Dietert
Department of Veterinary Pathology, Freie Universität Berlin
Ulrike Behrendt
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Jasmin Lienau
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Sandra-Maria Wienhold
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Achim D. Gruber
Department of Veterinary Pathology, Freie Universität Berlin
Norbert Suttorp
Department of Infectious Diseases and Respiratory Medicine, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Martin Witzenrath
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Geraldine Nouailles
Division of Pulmonary Inflammation, Charité — Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health
Abstract Background Community-acquired pneumonia (CAP) remains a major cause of death worldwide. Mechanisms underlying the detrimental outcome despite adequate antibiotic therapy and comorbidity management are still not fully understood. Methods To model timely versus delayed antibiotic therapy in patients, mice with pneumococcal pneumonia received ampicillin twice a day starting early (24 h) or late (48 h) after infection. Clinical readouts and local and systemic inflammatory mediators after early and late antibiotic intervention were examined. Results Early antibiotic intervention rescued mice, limited clinical symptoms and restored fitness, whereas delayed therapy resulted in high mortality rates. Recruitment of innate immune cells remained unaffected by antibiotic therapy. However, both early and late antibiotic intervention dampened local levels of inflammatory mediators in the alveolar spaces. Early treatment protected from barrier breakdown, and reduced levels of vascular endothelial growth factor (VEGF) and perivascular and alveolar edema formation. In contrast, at 48 h post infection, increased pulmonary leakage was apparent and not reversed by late antibiotic treatment. Concurrently, levels of VEGF remained high and no beneficial effect on edema formation was evident despite therapy. Moreover, early but not late treatment protected mice from a vast systemic inflammatory response. Conclusions Our data show that only early antibiotic therapy, administered prior to breakdown of the alveolar–capillary barrier and systemic inflammation, led to restored fitness and rescued mice from fatal streptococcal pneumonia. The findings highlight the importance of identifying CAP patients prior to lung barrier failure and systemic inflammation and of handling CAP as a medical emergency.
