A 3 year old girl is brought to the emergency room by EMS after having diarrhea and a history of fever for 5 days. She has a history of occasional constipation. Immunizations are up to date.  Family history reveals that the patient has an older brother with eczema. Social history is unremarkable. Upon examination, the patient appears unwell. The patient is responsive but lethargic. The neurological,respiratory, and skin exams appears normal. The cardiovascular examination shows normal heart sounds. Mucous membranes are dry, pulses are palpable but weak, capillary refill is 5 seconds centrally and peripherally. The abdominal examination reveals diffuse but non-peritonitic tenderness.