Recurrent Group B Streptococcus Infection in an Extremely Premature Infant from Neonate to Toddler: A Case Report

Summary

• Group B streptococcus infection is a significant cause of neonatal disease, occurring early-onset (<7 days) or late-onset (7–89 days).
• GBS infection risks neurodevelopmental impairment, especially in premature infants (<37 weeks).
• Management of recurrent GBS lacks systematic evidence, but the concurrent treatment of infant mucosae and breastmilk with well-tolerated agents like rifampicin is well-documented.

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Introduction

Group B streptococcus (GBS) infection is a significant cause of neonatal morbidity and mortality worldwide.¹ It can manifest as early-onset (EOD) or late-onset (LOD) infection.² Various initiatives, including intrapartum antibiotic prophylaxis, aim to reduce GBS-related complications, but LOD incidence has risen despite these efforts. Recurrent GBS infection occurs in a 0.5%–3% percentage of infants with LOD.^3,4 Proposed mechanisms include Nosocomial exposure, gut or breastmilk colonization, infective focus persistence (e.g., abscess), and insufficient treatment duration or agents. Prematurity is a risk factor for both LOD and recurrent GBS infection.⁵ This case report presents a premature female infant with five discrete episodes of recurrent GBS infection.⁶

Case Presentation⁶

• The female infant was born at 23⁺² gestation, weighing 580 g, via breech vaginal delivery.
• Received antenatal steroids, magnesium sulfate, and prophylactic erythromycin.
• Intubated, given surfactant, and treated with antibiotics for Staphylococcus epidermidis and Group B Streptococcus infections.

Investigation⁶

• Urine and stool cultures were negative in all episodes.
• Blood culture isolates from episodes 2, 3, 4, and 5 were all GBS serotype III, sensitive to amoxicillin.
• Imaging showed no evidence of infective foci or abnormalities.
• Maternal expressed breastmilk was GBS DNA positive by PCR.
• Immunoglobulin concentrations were low but normalized later.
• Neutrophil phagocytic function was normal.

Differential Diagnosis⁶

Recurrent GBS infection in an extremely premature infant must be distinguished from other causes of recurrent infections. Investigation and exclusion of inborn errors of immunity, variants in specific genes (e.g., C2, IRAK4, MyD88), and other pathogens are essential to reach an accurate diagnosis.

Treatment⁶

Initially, the Infant received gentamicin and benzylpenicillin; which stopped after negative blood cultures. Started Expressed breastmilk (EBM) and parenteral nutrition, then vancomycin for Staphylococcus epidermidis. Later switched antibiotics for GBS infection, but faced four more GBS infections. Prophylactic measures were taken. Breastfeeding stopped at 7 months, and antimicrobial prophylaxis at 17 months.

Table 1: Summary of GBS episodes, microbiology findings, and treatment outcomes.⁶

Outcome and Follow-Up⁶

Despite the turbulent early life course and prematurity, the patient remains well on antimicrobial prophylaxis. She is developing appropriately for her age (2.5 years old) and has not experienced other significant infections.

Discussion⁶

Recurrent GBS infection in premature infants is a concerning and complex clinical challenge. Prematurity, iatrogenic risks, and the immature neonatal immune system contribute to increased susceptibility to GBS infection and complications. Breastmilk’s role in recurrent GBS infection is unclear, and the mechanisms for transmission require further research. The patient’s treatment course, including prolonged antibiotic use, may have impacted her immune response. Inborn errors of immunity and genetic variants in specific genes are important considerations in patients with recurrent infections, but none were identified in this case. The patient’s continued need for antimicrobial prophylaxis indicates further monitoring and research to understand the mechanisms underlying recurrent GBS infection in premature infants.

Conclusion⁶

This case report highlights the challenges of managing recurrent GBS infection in premature infants. Despite appropriate treatment and prophylaxis, the patient experienced five episodes of GBS infection. Further research is needed to understand the underlying mechanisms and develop more effective preventive strategies for this vulnerable population.

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References

1. O’Sullivan CP, Lamagni T, Patel D, et al. Group B Streptococcal disease in UK and Irish infants younger than 90 days, 2014-15: a prospective surveillance study. Lancet Infect Dis 2019; 19: 83-90. DOI: 10.1016/S1473-3099(18)30555-3
2. Daniels JP, Gray J, Pattison HM, et al. Intrapartum tests for group B Streptococcus: accuracy and acceptability of screening. BJOG 2011; 118: 257-265. DOI: 10.1111/j.1471-0528.2010.02725.x
3. Zimmermann P, Gwee A, Curtis N. The controversial role of breast milk in GBS late-onset disease. J Infec 2017; 74: S34-S40. DOI: 10.1016/S0163- 4453(17)30189-5
4. Freudenhammer M, Karampatsas K, Le Doare K, et al. Invasive group B Streptococcus disease with recurrence and in multiples: towards a better understanding of GBS late-onset sepsis. Front Immunol 2021; 12: 617925. DOI: 10.3389/fimmu.2021.617925
5. Green PA, Singh KV, Murray BE, et al. Recurrent group B Streptococcal infections in infants: clinical and Microbiologic aspects. J Pediatr 1994; 125: 931-938.
6. Schim van der Loeff I, Tsilifis C, Abdelhafiz K, et al. Recurrent group B stretococcus infection in an extremely premature infant: as a preterm neonate, infant and toddler. BMJ Case Rep 2023; 16: e255216. DOI: 10.1136/bcr-2023-255216