Perineuritis Successfully Treated with Early Aggressive Immunotherapy.

Perineuritis is a rare type of peripheral neuropathy defined by swelling and cellular infiltration in the perineurium. We herein report a 52-year-old man who presented with subacute onset pain from the back to the lower limbs, muscle weakness and hypoesthesia. A sural nerve biopsy revealed perineuritis, consisting of inflammatory cell infiltration and swelling of the perineurium. Oral prednisolone, plasma exchange and intravenous immunoglobulin treatment were all effective, leading to significant improvement of the symptoms.