A 34-Day-Old With Fever, Cerebrospinal Fluid Pleocytosis, and Staphylococcus aureus Bacteremia.

A 34-day-old previously healthy boy born full term presented to the emergency department with fever at home (38.1°C), fussiness, and decreased oral intake for 1 day. He was difficult to console at home. He had decreased oral intake without emesis, diarrhea, or a change in urine output. He did not have rhinorrhea, cough, or increased work of breathing noted by parents. He lived at home with his parents and 13-year-old brother, did not attend day care, and had no sick contacts. On examination, he was fussy but consolable. He was febrile to 39.3°C, tachycardic (180 beats per minute), and tachypneic (64 breaths per minute), with mottling and a capillary refill of 3 seconds. The remainder of his examination was normal, without an infectious focus for his fever. A complete blood cell count with differential revealed leukocytosis. A basic metabolic panel was normal. A catheter urinalysis was normal. Cerebrospinal fluid examination yielded pleocytosis, low glucose, and elevated protein. Blood cultures were persistently positive with methicillin-sensitive Staphylococcus aureus, but cerebrospinal fluid cultures remained negative. We present his case, management, and ultimate diagnosis.