Review Question - QID 212603

An 11-year-old boy is brought to the emergency department by his parents for confusion and fever. The patient began complaining of a headache yesterday afternoon that progressively got worse. After waking him up this morning, his mom noticed that “he seemed funny and wasn’t able to carry a conversation fully.” When asked about his past medical history, the dad claims that he’s been healthy except for 2-3 episodes of finger pain and swelling. Physical examination demonstrates a boy in moderate distress, altered mental status, and nuchal rigidity. A CSF culture reveals a gram-positive, diplococci bacteria. What characteristic would you expect in the organism most likely responsible for this patient’s symptoms?