People with HIV also may have increased risk for neurosyphilis, syphilis complications involving the brain and nervous system. Therefore, if you have HIV and are treated for syphilis, it is important that you follow up carefully with a doctor to make sure your syphilis infection has been successfully cured. People with HIV sometimes have unusual results (higher or lower than they should be) on syphilis blood tests, which can make syphilis harder to diagnose. Syphilis symptoms may also be mistaken as something to do with having HIV and your doctor might not check for sexually transmitted infections during your regular check-ups. So if you have HIV/AIDS and are sexually active, get tested for syphilis especially if you've not had one in the last 6 months.