Neurosyphilis is a serious infection caused by the bacterium Treponema pallidum, which is the same bacterium responsible for syphilis. This condition occurs when the infection spreads to the central nervous system, affecting the brain and spinal cord. Symptoms can vary widely and may include headaches, changes in mood, memory problems, and difficulty with coordination. If left untreated, neurosyphilis can lead to severe complications, including paralysis, dementia, and other neurological issues. Diagnosis typically involves blood tests and examination of cerebrospinal fluid. Treatment usually consists of antibiotics, which can effectively manage the infection if administered early.