ETIOLOGY AND THERAPEUTIC MANAGEMENT OF LOWER RESPIRATORY TRACT INFECTIONS: A CURRENT REVIEW

Kacper Cholewiński; Dominika Karolak; Tymoteusz Białowąs; Natalia Kuśmierowska; Daria Valipur Kolti; Monika Kuś; Grzegorz Słomkowski; Milena Polak; Magdalena Nowak; Konrad Wiśniewski

doi:10.31435/ijitss.2(50).2026.5375

Authors

Kacper Cholewiński Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0004-7185-5310
Dominika Karolak Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0007-1131-9171
Tymoteusz Białowąs Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0001-0889-2635
Natalia Kuśmierowska Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0006-7572-0282
Daria Valipur Kolti University Clinical Centre, Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0005-9900-4419
Monika Kuś Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0009-6445-5593
Grzegorz Słomkowski Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0003-3742-8377
Milena Polak Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland https://orcid.org/0009-0007-6148-5354
Magdalena Nowak Cardinal Stefan Wyszyński University in Warsaw, Kazimierza Wóycickiego 1/3, 01-938 Warsaw, Poland https://orcid.org/0009-0002-1010-3364
Konrad Wiśniewski Cardinal Stefan Wyszyński University in Warsaw, Kazimierza Wóycickiego 1/3, 01-938 Warsaw, Poland https://orcid.org/0009-0007-1076-6471

DOI:

https://doi.org/10.31435/ijitss.2(50).2026.5375

Keywords:

Lower Respiratory Tract Infections, Pneumonia, Etiology, Antibiotic Therapy, Diagnostics, Streptococcus Pneumoniae

Abstract

Lower respiratory tract infections remain a primary global cause of morbidity and mortality, particularly devastating for children under five and adults over seventy. This study focuses on analyzing the diverse etiology of these infections – including viral, bacterial, and atypical pathogens – to establish therapeutic algorithms that ensure effective treatment while curbing the critical issue of antimicrobial overuse. Based on an extensive review of current literature and epidemiological data, the research highlights community-acquired, hospital-acquired, and ventilator-associated pneumonia. Findings from 2023 indicate that general mortality rates have returned to pre-pandemic levels, though mortality remains highest when pneumonia precedes mechanical ventilation. While Streptococcus pneumoniae is the leading bacterial cause of death globally, Staphylococcus aureus and Pseudomonas aeruginosa dominate hospital settings. Among young children, Respiratory Syncytial Virus (RSV) is the primary pathogen. Management strategies identify amoxicillin as the first-line treatment for community-acquired cases, whereas hospital-acquired infections require empirical coverage for MRSA and Gram-negative bacteria. Prevention is bolstered by vaccinations and monoclonal antibodies like Nirsevimab for RSV. Ultimately, because lower respiratory tract infections etiology is highly dependent on age and comorbidities, rapid differential diagnosis is essential to combat antibiotic resistance. Effective prevention through immunization and patient education remains the most successful strategy for reducing hospitalizations related to severe respiratory infections.

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