Fatal recurrent dermatoneuro syndrome associated with systemic AL amyloidosis.

A male patient is presented with long-lasting paraproteinemia of monoclonal IgG λ, who suffered from recurrent, and until the last one, mostly reversible episodes of dermatoneuro syndrome, described exclusively in scleromyxedema. The skin biopsy revealed λ-light chain amyloid deposition instead of changes typical for scleromyxedema. Systemic AL amyloidosis was diagnosed post mortem since the patient had no clinical signs of any other organ impairment except skin and brain. Neuropathology is described and possible etiopathogenesis of brain involvement is considered.