If it was a female hormone you could bet your last dollar that a physician would know all about it, but not a seemingly obscure male hormone.
Next time you are in your gps surgery look and see how many male magazines you can find in the waiting room.
I would doubt there are many- no matter where you are.
It is unfortunate but a fact that women have pushed knowledge, understanding and treatment for decades where as men have avoided doctors where possible and sat on their collective arses.
As a result we have physicians that no little to nothing about male health, particularly such dark issues as male hormonal health.
A funny but true story;
I was asked once by my gp who specialized in women’s fertility and ran clinics on the matter, I was asked;
Does testosterone come from the adrenals?
I had to inform here that its origin was a little lower and draw her a dirty picture 
The fact is very few gps will have a clue about testosterone never mind dihydrotestosterone (DHT).
DHT can be tested for though many a doctor and even endocrinologist will often say otherwise.
The problem with testing for DHT is that it has a very limited metabolic half life and the clinical importance of a one off test a little limited. If tested for it is good to get multiple samples- say three samples over the space of an hour. This should be done in the morning prior to 11am in line with the natural male circadian hormonal rhythm.