Perinatal infection screening and prevention — case

Case summary

A term male is born at 39 weeks by spontaneous vaginal delivery after 18 hours of ruptured membranes. The mother is known to be Group B Streptococcus positive on a 36-week swab, but she received only one dose of intravenous benzylpenicillin two hours before delivery. Her booking antenatal screens were normal except that she is hepatitis B surface antigen positive. At four hours of age the infant is grunting, tachypnoeic (respiratory rate 72) and has cool peripheries and poor feeding. [1] [3]

Candidate tasks

1. Take a focused history and examine the infant; formulate a one-line problem representation. [5]
2. Outline your immediate and stepwise management. [3] [9]
3. Counsel the parents about the early plan and the hepatitis B issue. [9]

Focused history and examination

• Antenatal and intrapartum: GBS-positive on 36-week swab; one dose of intrapartum penicillin (inadequate — fewer than four hours before delivery); 18 hours of ruptured membranes; no maternal fever or chorioamnionitis; HBsAg positive at booking with otherwise normal screens. [3]
• Examination: grunting, tachypnoea (RR 72), subcostal recession, cool peripheries and poor perfusion, poor feeding. No dysmorphism, no rash, no organomegaly, normocephalic, normal tone. [1]
• Functional assessment: the infant is in early respiratory failure with signs of shock — a septic, unstable neonate needing immediate escalation. [5]

One-line summary: "A 39-week male with inadequate intrapartum GBS prophylaxis, now grunting, tachypnoeic and poorly perfused at four hours — probable early-onset GBS sepsis; full septic screen and empiric benzylpenicillin and gentamicin now, plus hepatitis B vaccine and HBIG because the mother is HBsAg positive." [1]

Immediate and stepwise management

• Stabilise airway, breathing and circulation: supplemental oxygen and respiratory support, establish intravenous access, treat poor perfusion with fluid boluses and inotropes as needed, escalate early to the neonatal team. [5]
• Full septic screen — blood culture, full blood count and differential, lumbar puncture, C-reactive protein, chest radiograph — then immediate empiric intravenous benzylpenicillin and gentamicin to cover GBS and E. coli. [3] [5]
• Hepatitis B prevention: give the hepatitis B vaccine plus hepatitis B immunoglobulin (HBIG) within 12 hours of birth because the mother is HBsAg positive; plan completion of the vaccine series and post-vaccination serology. [9]
• Admit to NICU; review antibiotic therapy as cultures and the clinical course clarify; plan discharge once stable, cultures negative or treated, feeding established, and with a documented immunisation and follow-up plan. [3] [9]

Counselling the parents

• Explain clearly that their baby has become unwell because the antibiotic given in labour did not have enough time to reach the baby before birth, allowing the Group B Strep organism to cause an early infection — this was not anyone's fault in labour, and the focus now is on treatment. [3]
• Set immediate expectations: the team will support the baby's breathing, give antibiotics through a drip straight away, and monitor closely; most infants improve quickly with prompt treatment, though the first hours are important. [1] [5]
• Address the hepatitis B issue honestly and constructively: because the mother carries hepatitis B, the baby will receive the hepatitis B vaccine and an additional protective injection (HBIG) within 12 hours, which prevents the great majority of infection and the lifelong liver risk that would otherwise follow — this is invisible but decisive prevention. [9]
• Invite questions, check understanding, and offer written information and a named contact for follow-up. [9]