My 8-year old daughter was having shortness of breath after playing sports, so we took her to her pediatrician, who referred us to a pulmonologist. After about a year of trying various medications to no avail, he asked us to bring her to child psychiatrist as he thought her breathing problems could be emotionally based.
We decided to do this as our daughter had been having having increasingly angry outburst and also showing some symtoms of depression (withdrawing from friends, looking sad) over the past couple of years. We had discussed this with her pediatrician and teachers and taken a number of steps to alleviate the situation - spending more time together, seeing a psychologist, etc. This had helped but she still seemed sad, so this seemed to be a good time to seek a psychiatric opinion.
The psychiatrist, who had excellent clinical skills, interviewed both my daughter and my husband and I over the course of several sessions. Her diagnosis was 'soft' bipolar disorder (not extreme mania/depression as in typical bipolar but still intense ups and downs). My husband and I didn't really agree with this - we thought that the problem was really depression - but were willing to hear her out. The psychiatrist suggested a number of medications which she felt could help, although she did not feel that we had to use medication at this time she thought it might be necessary in the future. The medications she suggested all had a chance of serious, possibly permanent, side effects. We did not want to use them at that time.
At this point I realized that although my daughter had obvious been examined by her pediatrician, she had not had an extensive medical exam designed to rule out any physically based reasons for her depression/bipolar disorder. I said that I wanted her to get a full blood test, including thyroid, to make sure that she was not suffering from any physical disease. I included thyroid because I had read or heard somewhere that thyroid problems could cause depression. The doctor agreed to do this, although she did say that it was "highly unlikely" that thyroid deficiency was at the root of the problems.
Well, to everyone's surprise (even mine) the tests did indicate a thyroid deficiency and she was started on medication. Her emotional problems did not go away completely, but were definitely lessened. She continued in therapy for a couple of more years and is now doing much better.
It's astonishing that three well-credentialed and otherwise competent physicians did not think of this possibility from the beginning. If I had not insisted on a thyroid test, she could possibly be taking risky psychiatric medicine right now.
By the way, all the physicians were at a first-tier, nationally known hospital in Boston.