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Weight loss

Once called "AIDS wasting," weight loss is a sign of more advanced illness and could be due in part to severe diarrhea.

"If you're already losing weight, that means the immune system is usually fairly depleted," Dr. Malvestutto says. "This is the patient who has lost a lot of weight even if they continue to eat as much as possible. This is late presentation. We still see a lot of these." It has become less common, however, thanks to antiretroviral therapy.

A person is considered to have wasting syndrome if they lose 10% or more of their body weight and have had diarrhea or weakness and fever for more than 30 days, according to the U.S. Department of Health and Human Services.

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