We routinely keep patients until the sensitivities come back. But I work on a pediatric unit, so we are always a bit different from the rest of the hospital at large. I suppose if the gram stain turns up positive, sending an otherwise healthy adult home on something with good coverage would be the normal thing to do for them. We keep our kiddos usually 3 days, sometimes 10. I forget we're not "normal" on our unit! (It is my normal, though!)