The King of Pop was spotted having inflamed skin with red and purple spots, along with a severely swollen cheek while visiting a Beverly Hills clinic.
The 50-year-old is allegedly receiving antibiotics via a drip to fight the brutal "staph" infection, which is resistant to conventional antibiotics and had spread to his entire body.
"It is possible that Mr Jackson has a staph infection or MRSA," the Sun quoted US celebrity plastic surgeon Dr Anthony Youn as saying.
"This is called a 'super-infection' because it is resistant to conventional antibiotics. It does look like his skin is red and inflamed and has become infected.
"It is possible Mr Jackson contracted it through surgery on his nose. There are occasions where patients contract the infection during plastic surgery procedures."
The singer's spokesman declined to comment.