If it helps your team to cope with this guy, consider that his personality is probably a symptom, too. Not one you can do anything about, but keeping that in mind might help you maintain a little emotional distance while in the moment.
My wife was a palliative nurse and had all kinds of horrible things said and done to her by patients. Oftentimes they were later diagnosed with a UTI which explained a whole lot, but didn’t particularly help in the moment.