Group B streptococcus neonatal virulence — MRCPCH TAS MCQ

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HardMicrobiologyGroup B streptococcus neonatal virulenceMRCPCH TAS

A 12-hour-old neonate has respiratory distress, shock and blood cultures growing beta-haemolytic Gram-positive cocci in chains. The mother had prolonged rupture of membranes. Which organism is most likely?

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Correct answer: C — Streptococcus agalactiae

Early-onset neonatal sepsis with beta-haemolytic Gram-positive cocci in chains is most consistent with group B streptococcus, Streptococcus agalactiae. Listeria is a Gram-positive rod, which does not match the microscopy. The pearl is that maternal colonisation and prolonged rupture of membranes increase early-onset GBS risk.

Reference: Nelson Textbook of Pediatrics; NICE neonatal infection guidance; RCPCH Theory examination syllabi