I am so sorry to hear about your brother... This is a patient forum and there is just no way to guess about the reason for the high fevers. I am assuming you mean Fahrenheit as centigrade would be... Well, I don't think he would survive.
It may be an infection or just his way to heal. I just had a major operation and I had a fever for about a month... I do hope he comes through okay. Please keep us posted.