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Pneumonia

Nature Reviews Disease Primers volume 7, Article number: 25 (2021) Cite this article

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Abstract

Pneumonia is a common acute respiratory infection that affects the alveoli and distal airways; it is a major health problem and associated with high morbidity and short-term and long-term mortality in all age groups worldwide. Pneumonia is broadly divided into community-acquired pneumonia or hospital-acquired pneumonia. A large variety of microorganisms can cause pneumonia, including bacteria, respiratory viruses and fungi, and there are great geographical variations in their prevalence. Pneumonia occurs more commonly in susceptible individuals, including children of <5 years of age and older adults with prior chronic conditions. Development of the disease largely depends on the host immune response, with pathogen characteristics having a less prominent role. Individuals with pneumonia often present with respiratory and systemic symptoms, and diagnosis is based on both clinical presentation and radiological findings. It is crucial to identify the causative pathogens, as delayed and inadequate antimicrobial therapy can lead to poor outcomes. New antibiotic and non-antibiotic therapies, in addition to rapid and accurate diagnostic tests that can detect pathogens and antibiotic resistance will improve the management of pneumonia.

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Fig. 1: Prevalence of microbial aetiologies of CAP in the USA and Europe.
Fig. 2: Prevalence of microbial aetiologies of CAP in India and China.
Fig. 3: Immune resistance.
Fig. 4: Tissue resilience.
Fig. 5: Histology of pneumonia.
Fig. 6: Associated features of pneumonia on plain radiography.

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Acknowledgements

A.T. is the recipient of ICREA award from Generalitat de Catalunya. C.C. is the recipient of the SEPAR fellowship 2018, a grant 2019 from the Fondo de Investigación Sanitaria (PI19/00207), and the SEPAR fellowship “Programa Mentor”. We thank J.J.T.H. Roelofs (Department of Pathology, Amsterdam UMC, Amsterdam, Netherlands) for his invaluable assistance with the section on lung pathology and in providing representative histopathology slides.

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Authors and Affiliations

  1. Department of Pneumology, Hospital Clinic of Barcelona, Barcelona, Spain

    Antoni Torres & Catia Cilloniz

  2. August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain

    Antoni Torres & Catia Cilloniz

  3. University of Barcelona, Barcelona, Spain

    Antoni Torres & Catia Cilloniz

  4. Biomedical Research Networking Centers in Respiratory Diseases (CIBERES and CIBERESUCICOVID study), Barcelona, Spain

    Antoni Torres & Catia Cilloniz

  5. Division of Pulmonary and Critical Care, New York Presbyterian/Weill Cornell Medical Center, New York City, NY, USA

    Michael S. Niederman

  6. Department of Pneumology, Hospital Universitario y Politécnico La Fe, Valencia, Spain

    Rosario Menéndez

  7. Scottish Centre for Respiratory Research, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK

    James D. Chalmers

  8. Division of Pulmonary and Critical Care, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA

    Richard G. Wunderink

  9. Center of Experimental and Molecular Medicine, Division of Infectious Diseases, Amsterdam University Medical Centers, Location Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands

    Tom van der Poll

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Contributions

Introduction (C.C. and A.T.); Epidemiology (C.C. and R.M.); Mechanisms/pathophysiology (T.v.d.P.); Diagnosis, screening and prevention (C.C. and A.T.); Management (M.S.N.); Quality of life (J.D.C.); Outlook (R.G.W); Overview of Primer (A.T. and C.C.).

Corresponding authors

Correspondence to Antoni Torres or Catia Cilloniz.

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Competing interests

A.T. has been a paid consultant to Pfizer, Jansen, and MSD, and a speaker for Pfizer and MSD. M.S.N. has received research grants from Shionogi, Bayer and Merck. He has been a paid consultant to Bayer, Merck, Paratek, Abbvie, Nabriva, and Thermo-Fisher. J.D.C. has received research funding from Astrazeneca, Boehringer-Ingelheim, Gilead Sciences, Glaxosmithkline, Insmed and Novartis; he has received consultancy fees from Chiesi, Grifols and Zambon. R.G.W. is a consultant to Merck, Shionogi, Polyphor, Microbiotix, bioMerieux, Curetis, KBP Biosciences, Idorsia and Accelerate. All other authors declare no competing interests.

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Nature Reviews Disease Primers thanks Y. Arabi, C. Ginocchio, K. Klugman, M. Metersky, N. Suttorp and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Torres, A., Cilloniz, C., Niederman, M.S. et al. Pneumonia. Nat Rev Dis Primers 7, 25 (2021). https://doi.org/10.1038/s41572-021-00259-0

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