I think the appropriate course of action would be to write a letter listing all of your concerns...not missing out a
single detail. Be in depth.
As others have said, use the
PsychCentral Autism Quiz/Screening test - but use it for more as a guidline for what to put in your letter to his care/support team. Also, you can complete the test and PRINT OFF THE RESULTS. This could help his care team with a diagnoses.
I'd say however, if you are once again told he does not have the condition, to leave it at that. I honestly believe that if he's not had any major flags up on their systems so far into treatment, then maybe you could begin to ask what diagnoses he could have.
However...also remember that a diagnoses isn't everything. Support can be provided without a diagnoses, even though in some cases it can help towards a recovery. Maybe cross match the symptoms/traits you see with his current diagnoses (if any) and other conditions you may not have considered yet.
Looking briefly over the symptoms/traits you've mentioned, I don't see it relating to Asperger Syndrome anymore than Bipolar Disorder, Borderline Personality Disorder or even Major Depressive Disorder.
Research these conditions, I believe you may see a lot of similarities for all three of the conditions I just mentioned.
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