Group A Streptococcus Brain Abscess in a Patient on Adalimumab Therapy

Brain abscesses represent a group of dangerous infections typically caused by a number of classic organisms. Group A streptococcus is a rare cause of brain abscesses and those patients that do have this particular condition will typically have a distal source of infection. We present a case of patient with a biopsy confirmed group A streptococcal without a distal source of infection. His only identifiable risk factor was his adalimumab therapy for ankylosing spondylitis. While adalimumab has not been linked to streptococcal infection in the past, it has been associated with multiple atypical infections and some of the consequences of its mechanism as a tissue necrosis factor alpha inhibitor can theoretically predispose patients to streptococcal infection when considered in conjunction with known streptococcal virulence factors. This case raises the question of whether the patient’s adalimumab therapy may have contributed to his unusual presentation of streptococcal infection and prompts further consideration and study of the risks of adalimumab and other similar immunosuppressant monoclonal antibodies.