Abstract

A REVIEW ON LOWER RESPIRATORY TRACT INFECTIONS

Fathima Basheera M.*, Natarajan P., Dhanasekaran M., Dheena Dhayalan P., Jeya Shree S., Ganga Dharshini R.

ABSTRACT

Lower respiratory tract infections (LRTIs) constitute one of the most significant causes of morbidity, mortality, and healthcare utilization worldwide. They encompass a broad spectrum of clinical syndromes including community-acquired pneumonia (CAP), acute bronchitis, acute exacerbations of chronic obstructive pulmonary disease (AECOPD), and acute exacerbations of bronchiectasis. Despite major advances in antimicrobial therapy, vaccination programs, and supportive care, LRTIs continue to impose a substantial burden, particularly among older adults, immune compromised individuals, and those with chronic comorbid conditions. The increasing prevalence of antimicrobial resistance, aging populations, and emerging respiratory pathogens further complicate management. This review provides an in-depth overview of the epidemiology, risk factors, microbiology, pathophysiology, clinical presentation, diagnostic approach,management strategies, complications, prevention, and future perspectives of adult LRTIs, with emphasis on evidence-based clinical practice.

Keywords: Lower respiratory tract infection, community-acquired pneumonia, acute bronchitis, COPD exacerbation, antimicrobial resistance, respiratory infections.