In a newborn presenting with vomiting and convulsions shortly after delivery, which organism is most commonly responsible?

• A. Haemophilus influenzae
• B. Neisseria meningitidis
• C. Staphylococcus aureus
• D. Escherichia coli

Answer: (D)

In a newborn presenting with symptoms such as vomiting and convulsions soon after birth, the most common organism responsible for these clinical manifestations, especially in the context of early onset infections, is Escherichia coli.

E. coli can lead to serious infections in neonates, particularly when there is a predisposing factor such as prematurity, maternal chorioamnionitis, or prolonged rupture of membranes. This organism is a common cause of early-onset sepsis in newborns, which can present with signs like poor feeding, vomiting, and neurological symptoms such as convulsions due to sepsis or meningitis.

The presence of these symptoms shortly after delivery indicates that the organism likely came from the maternal genital tract or through the birth canal. E. coli strains can be especially virulent due to their ability to produce endotoxins and other virulence factors that can lead to rapid clinical deterioration in newborns.

Understanding the infectious risks and the typical pathogens involved in early-onset sepsis is crucial for prompt diagnosis and treatment, making E. coli a key organism to consider in these scenarios.