(Click the link to comment and to vote – voting not working through email, sorry!)

You are seeing an 8 year old girl with fever of unclear etiology for 7 days. She is well appearing. Exam reveals 1-2cm tender nodes in her left axilla and left anterior cervical areas. She has a superficial healing scratch on her left forearm, and history reveals that she has been spending time at a cousin’s house with the cousin’s new kitten. She is also noted to have hepatomegaly 2cm below the right subcostal margin, and a palpable spleen tip. She has no petechiae or purpura. The remainder of her exam is noncontributory. 

Which is the best treatment for her presumed condition?