Retropharyngeal abscess caused by Streptococcus agalactiae: A case report and literature review.

A previously healthy 79-year-old man who developed a retropharyngeal abscess secondary to Group B Streptococcus (GBS) infections is reported. Comprehensive imaging evaluation revealed a retropharyngeal abscess due to pyogenic spondylitis was made, which progressed to an epidural abscess and descending necrotizing mediastinitis. Successful treatment with surgical drainage and antimicrobial chemotherapy suggests that with prompt diagnosis and appropriate management, outcomes can be favorable even in severe presentations. The pathogenesis of invasive GBS infection in the elderly is multifactorial. Immune senescence and bacterial translocation may play an important role. This case report highlights an important shift in the microbiological landscape of invasive GBS infections, particularly in adults.