Health Highlights: July 10, 2009

What's known about Jackson's other medical conditions may also point to lupus, Dr. Robert Lahita, an autoimmune disease expert and a professor of medicine at Mount Sinai Medical School, told "Good Morning America."

"He had a form of skin lupus, called discoid lupus, which affects about 40 percent of the patients with lupus," Lahita said. Discoid lupus can lead to depigmentation of the skin, among other problems.

"Michael Jackson acknowledged having vitiligo, having splotches of the skin," Lahita said, ABC News reported. Vitiligo is common with autoimmune disease. Patients with vitiligo are normally advised to avoid sun expsoure, which may explain Jackson's use of an umbrella on sunny days.

The white glove and surgical masks may have been used to camouflage the white skin patches caused by vitligo, he said.