How frustrating! It should not matter whether you have pouchitis, a virus, food poisoning, or hysterics. If you are dehydrated and need IV hydration, the treatment is the same. Follow up antibiotics, if needed, are secondary. Perhaps your signs and symptoms had not reached the tipping point yet to be clear. Just trying to give the benefit of the doubt here to the ER doc, but still... some docs just look at the numbers, and not the patient and the history, but that takes time.