Japanese researchers describe the case in the Journal of Neurology, Neurosurgery and Psychiatry.
Dr Gen Sobue told Reuters Health that intravenous immune globulin or IVIg "was effective in improving severe pain symptoms and muscle weakness" in this patient.
Sobue and colleagues at Nagoya University School of Medicine say their patient was a wheelchair-bound 57-year-old man who had had type 2 diabetes for 10 years.
He showed progressive loss of muscle strength in both legs, pain and muscle wasting in the thighs, and significant weight loss.
Treatment with IVIg infusions for five days led to a remarkable improvement in pain and muscle weakness, the team reports.
The man's pain began to return over the following three weeks, but a repeat course of IVIg brought it down again.
The man continued to have severe problems with ankle mobility, but after the IVIG sessions he could walk with a cane. Previously he had been unable to stand, let alone walk.
Sobue concluded that there are some diabetic patients with nerve damage "whose pain can be ameliorated, and thereby possibly quality of life can be improved, by IVIg therapy." - (David Douglas, Reuters Health)
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