Wife had an episode about a week ago. On the way to church, we ask me to take her home. Her stomach had been queasy and feel the urge to used the bathroom but could not. She tried to go but no luck. She had not had a bowel movement for a few days. She wanted an enema so I gave her a rectal enema. She went some time later but stool was bloody. It continued to have blood in the stool for a few days, then went away. She had an episode today with a little blood. What is the cause ???