I sold this Axolotl back in 2011 but it was returned to me in 2015 as the person who had it said it was unwell. It was in a very poor state and three days later it died in front of me.
I performed a basic necropsy of it and saw how ill it had been its stomach was empty and starting to shrivel and its liver was covered in lesions and spots.
It turned out that it had Mycobacterium Marinum which is more commonly known as Fish TB and is pretty contagious to humans.
It turned out that the Axolotl had been poorly looked after and was in a tank that had a heater so given all that it had developed pathogens that was bad for it and eventually killed it. The poo thing was in a lot of pain and suffered a horrible death.
Remember Axolotls are NOT fish so do not treat them like one
Is it a Fish? NO, Is it a Reptile? NO, Is it a Tadpole? NO......What is it?, It's an Axolotl