Others are caused when HIV infects the brain or spinal cord. Mental problems usually don't show up until the late stages of HIV disease. If someone with a high T-cell count develops a neurologic problem, their doctor will look for other causes. These might include depression or the aging process. You should tell your doctor if you have any signs of HIV-related neurologic problems.
Some neurologic problems require urgent medical attention.
If you have serious headaches, especially with a fever, stiff neck, vomiting, or vision problems, you should see your doctor immediately. Central nervous system problems can be caused by medications, by swelling, or by direct HIV infection of the brain and spinal cord. If nervous system problems are caused by medications, they usually go away if you stop taking the drugs. HIV infection of the central nervous system has to be treated with antiviral drugs. It's a tight network of blood vessels that protects the brain and spinal cord from most germs or poisons in your blood.