Was one of the reasons for Hitler's hatred for the Jews caused by the death of his mother while in the hands of a Jewish doctor?

Hitler hated the Jews for a lot of reasons. One was because he thought they had "back-stabbed" Germany during WW1.

Most unlikely. His mother died in 1907 and, according to Ian Kershaw's highly acclaimed biography, the first evidence of real antisemitism on Hitler's part dates from 1916.

I've read that Hitler was actually quite grateful to the Jewish doctor who treated his mother, additionally, he allowed the doctor to escape Nazi Germany unscathed later on. I think that if he was that angry at the doctor, he probably would have had him sent to a concentration camp.

See the related questions.