Doctors said that because of Brown's age he didn't have the classic criteria for a Type 1 diagnosis, although it is possible. A ketoacidosis diagnosis from Type 2 diabetes, though uncommon, is more likely to occur in African-Americans, said Rita Kalyani, an assistant professor of medicine in the division of endocrinology and metabolism at Johns Hopkins.
But athletes learn to push through the pain, so Brown may have had a higher tolerance for sickness.
"Professional athletes are used to feeling pain," Williams said. "It's almost a daily activity."
It is also possible that Brown could have confused some of the symptoms for general sickness. Thirst andfrequent urination are early signs of diabetic ketoacidosis. Other symptoms such as dry or flushed skin and shortness of breath later appear.
The medical examiner said over-the-counter flu medicine was found in Brown's apartment, giving some indication that he might have felt sick. But it was unclear how long the medicine had been there.
Fowler said that a relative indicated Brown might have been feeling sick for a few weeks.
"For someone who is undiagnosed, they may not know they have diabetes," Kalyani said. "The symptoms may occur gradually, and people may not recognize them."
Kalyani said some people wind up in the emergency room and are diagnosed there.
Marc I. Leavey, an internist with Mercy Medical Center's Lutherville Personal Physician's site, said the progression of the disease could have developed quickly. The condition can develop slowly but when vomiting occurs, the symptoms can quicken and in a few hours, according to the American Diabetes Association.
"You can develop rapidly onset diabetes," Leavey said. "If he didn't know it was there, the whole thing could have happened in a couple of weeks."
Kalyani said Brown's case demonstrates the need for continued diabetes education.
"We need to do as much as we can to build community awareness and patient education," she said. "We hope to reach those who may not know they have diabetes so we can prevent this kind of thing from happening."
Warning signs of ketoacidosis
The condition can develop slowly but when vomiting occurs can rapidly speed up.