Case 1
A 9-day-old female infant presents to the emergency department with a 1-day history of fever and poor feeding. She was born at term with a birth weight of 3.1 kg to healthy parents. Prior to the last 24 hours, she had been breast-feeding well and making good progress.
On examination, she is febrile at 38.3 and is moderately dehydrated. She is floppy but alert and irritable on handling. Her weight is 2.9 kg. Her heart rate is 160 beats/min, capillary refill time 3 s, respiratory rate 40/min. There is no rash and her fontanelle is normal.