Any time a med student mentions something about dissociation (why is this so high on every MS's differential?), I usually tell them "*this institution* doesn't believe in dissociation." Because I'm pretty sure it is requisite to not believe in DID to work in my department. There's one guy at the VA who does, and when we rotate with him he spends quite a while educating/convincing us about DID.
I've had a few, not many, cases of people with a dissociative disorder who were misdiagnosed as being psychotic.
It's hard to differentiate between someone who is severely dissociating and psychotic, but I think it needs to be on someone's radar.
One example, I had a young female patient who's husband left her, he provided her with a good life, and she couldn't take care of herself. She ended up in the homeless shelter. While there, she started staring off into space and mumbling to herself. She was brought to the hospital and diagnosed as being psychotic. She was like that for about 5 days while on high doses of an antypical and Depakote.
Then her husband tells the treatment team he's going to take her back--she's immediately better. In fact she's not even taking the medication anymore and she's doing fine for 2 days.
Then 2 days later, he changes his mind. She's back to staring off into space and mumbling when asked questions.
This IMHO was not psychosis. It was IMHO dissociation in the face of a major stressor--the loss of her husband, her children (because he will get custody--she was a former stripper, he was a white collar guy), a severe drop in the quality of her life that she saw no hope in getting back.
I bet if he came back and told he he changed his mind again, she'd be fine. That clearly is not psychosis by our understanding of it.
To medicate someone like this is actually causing harm because it's going to start a fast trip to nowhere---a patient who is not psychotic being put on several antipsychotics, and eventually Clozaril because they don't show improvement.
Another case, didn't happen to me but one of my teachers, a guy wanted out on his marriage and preplanned it without letting his wife know. Then one day she comes home and the locks on the doors are changed. He actually had her sign documents that she did not know what they were that were post nuptial papers (the guy had money). He also arranged with his lawyer to have a restraining order put on her even though she did nothing dangerous.
She could not get into her home and she had no means to take care of herself. Just 1 month prior, her husband threw a large party for her in her honor proclaiming what a great wife she was. All her credit cards were also in his name and he cut her off from them.
She went into a state of acute emotional despair and ended up in the hospital. She was never psychotic and said something to the effect of "I can't believe my husband did this. It's as if he's been replaced by an evil double." She was also showing signs of dissociation such as staring off into space.
Well that was enough for the psychiatrist to have her placed on mega doses of an antipsychotic which then heavily sedated her to the point where she couldn't even stand up. She was then deemed not able to care for herself in the community and brought to the inpatient unit where she was then continued on this dosage. Her idiot treatment team never considered that this was an old lady, she was dependent on her husband, and she was in a state of emotional despair, and she really wasn't even psychotic, and 20 mg of Zyprexa could knock out this person of old age who was of low weight. Her treatment team described her as "confused", "disorganized" and unable to care for herself.
She didn't improve from her mega doses of Zyprexa, and actually took the medication thinking that if a doctor recommended it, there might actually be something to it that she should believe would help her. She was then transferred to a long term facility where she stayed for several months.
Finally, the doctor I mentioned was put on her case, he reviewed it, and talked to the psychiatrist about it (the doc I'm talking about is a psychologist). The patient was taken off of medication, and when taken off, she showed no signs of psychosis. She readily admitted she said that she said something to the effect that her husband may have been replaced and said it was a figure of speech.
I hate saying this, but I see this type of case happen from time to time, perhaps on the order of at least 3 per year. Someone misdiagnosed, put on the wrong treatment, then put on a fast trip to nowhere where they'll stay trapped for a long long long long time until someone took the time to actually truly read the case and try to understand what was going on, not just throw a pill at the most obvious symptom.