But new research reveals a possible cause and cure.
Lou Baxter explains in this week's Health Report.
Laura Waslo is passionate about the guitar, but in 2009 chronic widespread pain prevented her from playing.
Laura Waslo, has autoimmune neuropathy, said: "It was a burning pain in my legs and feet, which were getting red and swollen all the time."
Several doctors told Laura it was nerve damage from her diabetes, but no one could make the pain go away, until she met doctor Anne Louise Oaklander who diagnosed Laura with autoimmune neuropathy.
Anne Louise Oaklander, MD, Massachusetts General Hospital, said: "I'm going to tap on your arms and legs. This is a particular type of widespread nerve damage that is different from the diabetic neuropathy."
Although it's been diagnosed in adults, doctor Oaklander's study of 41 patients found it also occurs in those under 21.
Dr. Oaklander, "Since no one knew what the cause of their pain and other symptoms were, there were no effective treatments."
In addition to chronic pain, Laura experienced insomnia, blood pressure swings and sometimes passed out when she stood up.
Dr. Max Klein, instructor in neurology, Massachusetts General Hospital, said: "The one from the patient on the right has far fewer nerve endings."
Through skin biopsies and heart and blood pressure tests, doctors discovered neuropathy in younger patients.
Dr. Klein, "We were seeing abnormal skin biopsy test results or abnormal autonomic function test results. These are things that previously had not been described in young patients."
Laura's pain level dropped with steroid treatment followed by transfusion therapy.
Laura Waslo, "I feel great now. My symptoms pretty much disappeared."
I'm Lou Baxter reporting.
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