Which organisms are commonly implicated in early onset neonatal pneumonia?

Which organisms are commonly implicated in early onset neonatal pneumonia?

• A. Staphylococcus, Pseudomonas
• B. RSV
• C. Group B Streptococcus, Escherichia coli, Klebsiella
• D. Listeria monocytogenes, Candida

Answer: (C)

Early onset neonatal pneumonia is usually acquired from the mother's flora during birth, so the most common offenders are organisms that commonly colonize the maternal genital and GI tracts. Group B Streptococcus (Streptococcus agalactiae) is the leading cause, transmitted perinatally and readily causing pneumonia and sepsis in newborns. Escherichia coli and Klebsiella are also frequently involved, reflecting maternal GI/urinary tract colonization and exposure at delivery. This pattern distinguishes them from pathogens more often seen later in a NICU stay (like Staphylococcus aureus or Pseudomonas) or from viral causes (such as RSV) that aren’t the typical early-onset bacterial culprits. Listeria and Candida can cause neonatal infection but are less common causes of early onset pneumonia and tend to be linked to specific risk factors. Thus, Group B Streptococcus, Escherichia coli, and Klebsiella best represent the organisms commonly implicated in early onset neonatal pneumonia.

Early onset neonatal pneumonia is usually acquired from the mother's flora during birth, so the most common offenders are organisms that commonly colonize the maternal genital and GI tracts. Group B Streptococcus (Streptococcus agalactiae) is the leading cause, transmitted perinatally and readily causing pneumonia and sepsis in newborns. Escherichia coli and Klebsiella are also frequently involved, reflecting maternal GI/urinary tract colonization and exposure at delivery. This pattern distinguishes them from pathogens more often seen later in a NICU stay (like Staphylococcus aureus or Pseudomonas) or from viral causes (such as RSV) that aren’t the typical early-onset bacterial culprits. Listeria and Candida can cause neonatal infection but are less common causes of early onset pneumonia and tend to be linked to specific risk factors. Thus, Group B Streptococcus, Escherichia coli, and Klebsiella best represent the organisms commonly implicated in early onset neonatal pneumonia.