Can a doctor be appointed as a patient's guardian?

I read that the court is considering appointing a guardian for a person with a mental disorder, and a situation arose where the head of the hospital department where the patient is currently located is intended to be appointed as the guardian. However, I heard that relatives should be given preference, and the patient himself was against it. Is it legal to appoint a medical professional from the hospital where the person is being treated as their official guardian if this person has close relatives? Doesn't this create a conflict of interest or a violation of such a person's rights?