Recurrence of Streptococcus agalactiae bacteremia - risk factors and complications.

Background: This study was undertaken to investigate the incidence and risk factors for Streptococcus agalactiae (GBS) bacteremia recurrence in patients following first episode of GBS bacteremia.

Methods: This was a retrospective observational study evaluating admitted patients from January 1, 2016 to 12/31/2019. Non-pregnant patients ≥18 years old with GBS bacteremia were included. Recurrence was defined as admission due to GBS bacteremia within 1 year after a positive GBS blood culture.

Results: Nineteen out of 388 patients with GBS bacteremia had recurrence. There was a significant increase in recurrence in patients allergic to β-lactams, in patients with implantable cardiac devices (ICDs), and in patients who did not receive β-lactams or vancomycin as empiric treatment. The estimated odds of recurrence in patients with allergy to β-lactams was 3.1 times the odds of recurrence without allergy after adjusting for ICD status (95 % CI, 1.1-8.9, p < 0.04). The estimated odds for recurrence in patients with ICDs were 5.8 times the odds of patients without ICDs controlling for β-lactam allergy (95 % CI, 1.7-19.9, p < 0.01).

Conclusions: Our study suggests that GBS bacteremia recurrence is associated with presence of ICDs, β-lactam allergy, and not having received β-lactams or vancomycin as initial treatment.