Wondering what this could have b..

Brief：
A few years back my parents got a kitten that seemed to be healthy. Well one day there was this spot on its back that seemed raw and it was oozing pus.. 

A few years back my parents got a kitten that seemed to be healthy.

Well one day there was this spot on it's back that seemed raw and it was oozing pus or something.

Every day it seemed to get bigger and bigger until all of the cat's back had no fur on it, just this raw, oozy spot.

I live out of state and had no idea that they even had a cat, but I went home to visit and saw this poor thing like that and threatened to call animal control if they did not bring the cat to the vet.

The next day when I went over, the cat was gone. I asked what happened to it and they said they dropped it off at the humane society, but I honestly believe the either dropped the cat off somewhere else to die or shot it. I'll never know. :( He was a gorgeous cat and I would have taken him if I'd only known sooner.

Anyway, I was just sitting here thinking about the poor thing and wondering if anyone had any idea of what could have been wrong with it?

It could have been any number of things, a bite, a cut, anything really that just got infected. It's sad that your parents didn't take care of it. You can always try to google the symptoms. Sounds like a B-B-gun shot wound that didn't get looked after. I myself wouldn't be speaking to them at this moment. No offense, but that's not a good example of your parent's responsibility towards animals. Thanks for giving me that picture in my head now. sheesh. It was just ringworm. Could have been treated with a course of antibiotics and anti-fungal cream. That's what they gave my cat when he had the same skin condition you described.