Pyogenic brain abscess caused by Streptococcus pneumoniae: case report and review

While Streptococcus pneumoniae is the most common cause of bacterial meningitis in adults, cases of pneumococcal brain abscess have rarely been reported. We describe a case of otogenic brain abscess caused by S. pneumoniae that developed in a patient who was receiving ciprofloxacin for the empirical treatment of otitis media. We also review 23 additional cases of pyogenic brain abscess caused by S. pneumoniae that have previously been reported. The development of a pneumococcal brain abscess was associated with a contiguous intracranial focus of infection in 50% of cases. The majority of patients presented with headache (81%) and focal neurological deficits (86%). However, the classic triad of headache, fever, and focal neurological deficits was present in only 24% of patients. The mortality rate for patients with brain abscess caused by S. pneumoniae was 35%; persistent neurological deficits were documented in 40% of patients who survived.