Office pediatrics: current issues in lower respiratory infections in children.

PURPOSE OF REVIEW: Recent estimates indicate that 1.9 million children worldwide die each year from acute respiratory illnesses, many of which are lower respiratory infections (LRIs). Global threats from indoor and outdoor air pollution, urban crowding, biologic weapons, and worldwide rapid transportation complicate our efforts to reduce the impact of LRI disease in children. As new strategies are developed to limit the spread of LRI disease in children, existing pathogens become more complex to treat and newer pathogens emerge as causes of clinical disease. Most LRI disease is managed in outpatient settings and remains a challenge to those who care for children.

RECENT FINDINGS: Atypical pathogens (notably mycoplasma pneumoniae) are now known to cause a wide spectrum of disease, and with more extensive complications than previously recognized. Available data suggest a rapid increase in S. pneumoniae resistance to penicillin and macrolides in many cases of community acquired pneumonia, which has resulted in shifts in outpatient (and inpatient) antibiotic treatment regimens. Human metapneumovirus (HMPV) is now recognized to cause LRI illness similar to respiratory syncytial virus (RSV) in infants and children. General strategies for the prevention of influenza infection are expanded to include many infants and young children, and are projected to significantly reduce morbidity and mortality from this key LRI pathogen.

SUMMARY: The spectrum of LRI pathogens--and the clinical illnesses caused by them--continues to change. Innovations in immunotherapy and vaccines will be instrumental to reducing the burden of LRI morbidity in infants and children worldwide in the future.