While discovered 150 years ago, the cause of MS remains unknown. What we do know is that nerve damage is caused by inflammation, but the cause of the inflammation is still unknown. This means that there is no cure yet. Because of the different types of MS and the plethora of possible symptoms, 50+ symptoms can be linked to MS. Many people can, therefore, go undiagnosed for any length of time. You may have a single symptom, and then go months or years without any others. A problem can also happen just one time, go away, and never return. For some people, the symptoms become worse within weeks or months. Some symptoms of multiple sclerosis are mild and cause inconvenience; others may be severe and debilitating.