eggs not being hatched

i have a RIR she has been laying for a few years with no problem,today she passed away after having a few signs of a health problem i thought it was coccidiosis but i wanted to be completely sure so i know which steps to take to protect the rest of my flock.
So i went out in my garage with her and proceeded to perform a necropsy and take a look at her intestines to be sure..what i discovered instead of any signs of coccidia were yolks right inside of her,it was a pile of yolk that was really watery and just ran out of her.
Could that have been the cause of death? has anyone ever heard of anything like backed up eggs killing a hen or posing a health risk to the hen?
feel free to leave links about this if anyone knows anything..thanks(=