Without HIV treatment, full-blown AIDS usually takes about a decade to develop. During this last phase of the disease, the virus severely damages the immune system to a point where the body can no longer fight a number of viral, fungal, bacterial and parasitic infections that invade. Any one of these infections is life threatening, and most people with AIDS eventually succumb to them.
While night sweats can also begin prior to developing full-blown AIDS, they also occur during this end stage. Night sweats are the result of repeated nighttime fevers greater than 100 degrees, and according to MayoClinic.com they usually occur with shaking chills.
When the HIV virus infects brain cells during the late stages of AIDS, patients experience a myriad of mental functioning impairment. According to the AIDS Education Global Information System, doctors call this condition AIDS dementia. Early symptoms of AIDS dementia mimic those of depression, such as loss of interest in favorite activities. As the disease progresses, symptoms can include memory and mobility problems as well as slowed mental functioning.
Chronic diarrhea and weight loss begin during earlier stages of the disease, and usually continue as full-blown AIDS progresses. When diarrhea lasts longer than a month, and leads to more than a 10 percent weight loss, doctors will diagnose AIDS wasting syndrome, according to Drugs.com. Decreased appetite caused by medication side effects, and painful mouth infections can exacerbate weight loss, as can nutrient absorption problems and metabolic changes common with HIV and AIDS. Efforts to reverse wasting include appetite stimulants, diarrhea medications and nutritional supplements.
Serious parasitic infections, also known as opportunistic infections, are common in patients with full-blown AIDS. The McKesson Corporation's website lists a cancer known as Kaposi's sarcoma, pneumocystis carinii pneumonia or PCP, tuberculosis, meningitis and herpes simplex infections as the most frequently seen opportunistic infections.