RT Book, Section A1 Brown, Lance A2 Cline, David M. A2 Ma, O. John A2 Cydulka, Rita K. A2 Meckler, Garth D. A2 Handel, Daniel A. A2 Thomas, Stephen H. SR Print(0) ID 56274144 T1 Chapter 71. Pneumonia in Infants and Children T2 Tintinalli's Emergency Medicine Manual, 7e YR 2012 FD 2012 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-178184-8 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=56274144 RD 2024/10/07 AB Most cases of pediatric pneumonia develop from inhalation of infective bacteria or viruses. The clinical presentation, likely etiologic agents, severity of illness, and disposition, vary with age. In the neonate, group B Streptococci, gram-negative bacteria, and Listeria monocytogenes, are important pathogens. In the 1 to 3 month old age group, infants may be afebrile with pneumonitis syndrome secondary to Chlamydia trachomatis, respiratory syncytial virus (RSV), other respiratory viruses, and Bordetella pertussis. In the 1 to 24 month age group, mild to moderate pneumonia can be caused by respiratory viruses as well as Streptococcus pneumoniae, Haemophilus influenzae, and Mycoplasma pneumoniae. Although viral pathogens dominate during years 2 to 5, the above bacterial pathogens are common. By the sixth year through 18 years of age, influenza virus A or B and adenovirus are common. At any age, severe pneumonia may be caused by S aureus, S pneumoniae, M pneumoniae, H influenzae B, and group A streptococci.