There was a post about this name a few weeks back.
It seems to be a version of the Name
Hilma. There are quite a few names in Brasil with or without a (silent) H as initial:
Heloísa -
Eloísa;
Hélio -
Élio;
Henrique -
Enrique;
Hilda -
Ilda ...
Maybe it was brought there by german and pomeranian migrants (it was most popular in Espírito
Santo).