Oh my god I'm so glad you asked this question. Some of the clients who I come into contact with on a daily basis display symptoms of various types of MI.

There's one guy who I work with from time to time who I believe is a medicated schizophrenic. He has the stereotypical "1000 yard stare" that I've seen in others who are actively psychotic, he has a strong preoccupation with religion (brings it up at inappropriate times and in inappropriate contexts), has very flat affect etc.

I met with one individual a couple of weeks ago who I actually thought may have been in the midst of a manic episode. He arrived to our meeting with NONE of the paperwork he was supposed to bring, spoke very quickly, overshared personal information (criminal history, drug use, etc.) and brought up stuff that was extremely inappropriate in a professional setting (told me about his sex life).

There are a couple of clients who are very aggressive when interacting with staff and other clients which leads me to believe they have anger issues or possibly even BPD.

When I was employed at a research laboratory in college one of the professors I worked for seemed "off" to me and my colleagues, and based off of the way he acted and some life stories he shared with myself and others I now strongly suspect that he has MDD or BP.

One day my current coworkers and I were having lunch and they started talking about a woman who used to work with them before I joined the team. They started talking about how she seemed totally normal until one weekend she began sending them a bunch of very bizarre, angry sounding emails and showed up for work the following monday and was being REALLY irate, someone tried to ask her what was up and apparently she looked at them with an expression her face that was like something out of a horror movie. Then all my coworkers started talking about how she probably had bipolar and brought up other examples of people they knew who had been diagnosed with BP.

I just sat there smiling and nodding like "Mmyep, nothing to see over here!"