@OwenGeo We are working on a StoryMap and the title includes the words "E. coli". Based on correct formatting, E. coli must be italicized, but this is not currently available. Thus our StoryMap title reflects poorly on us.
I've used unicode characters as a workaround to get italicized characters into the title of an ArcGIS StoryMap. There are italic characters in Unicode's Mathematical Alphanumeric Symbols block (see Wikipedia's helpful table for the codes.)
If you're unsure how to directly enter unicode characters, you can use your operating system's helper app, and cut-and-paste from there: