Polymicrobial subdural empyema: involvement of Streptococcus pneumoniae revealed by lytA PCR and antigen detection.

The authors report a case of a subdural empyema (SDE) caused by a coinfection with Streptococcus intermedius and Streptococcus pneumoniae, initially considered a S. intermedius infection only. An otherwise healthy 11-year-old female was admitted to the hospital after 5 days of illness. Symptoms were consistent with classical SDE symptoms and progressed rapidly with finally somnolence before the first neurosurgical procedure despite relevant antibiotic treatment. Primary MRI showed an interhemispheric SDE and a postoperative control CT scan showed progression of the empyema infratentorially. The empyema was evacuated twice, day 8 and 18, with good results. Primary samples showed growth of S. intermedius only. The severity of the clinical picture elicited supplementary samples, which were additionally positive for S. pneumoniae by an in-house specific lytA PCR and/or a commercial antigen test.