Rectal Tenesmus

Hello, my name is Roberto, I’m writing from Italy (and please sorry for my English).
I am asking your help about my mother. She is suffering since a few years an anomalous ache.
She has vey strong anal contractions (particularly in the muscle situated between ano and inguine).
They are very strong and continous contractions and they have become an obstacle to a normal day by day life.
In the beginning she suffered of stipsi. Doctors believed it being the cause of contractions and decided for a surgical operation. They removed a piece of intestine without resolving the problem.
In a second time they removed another piece of intestine, but the result was negative too.
The third time they removed the colon and the situation got worst.
Presently she has to remain closed at home because she needs the toilette about 15 times in a day.
She losted confidence and hope.
If someone lived something similar please tell me. It could be important for her to know that there is something in the world living a similar contraction, because doctors we went to are not able to find neither the cause nor the solution to this strange disease.
Thanks ROberto