FAMILIAL AMYLOIDOTIC POLYNEUROPATHY TYPE-I WITH EXTRACELLULAR-SUPEROXIDE DISMUTASE MUTATION - A CASE-REPORT

We report an autopsy case of familial amyloidotic polyneuropathy (FAP) Type I with mutations in both transthyretin (TTR) and extracellular s uperoxide dismutase (EC-SOD). This patient started to develop peripher al neuropathy at age 25, followed by cardiac, renal, and autonomic ner vous system failure due to massive amyloid deposition. Thirteen years after the initial symptoms, he died of septic shock. Autopsy revealed suppurative peritonitis, multiple abscesses in the bile ducts and urin ary tract, and more marked amyloid deposition than commonly seen in FA P. Amyloid deposition occurred in various organs and tissues, especial ly prominently around blood vessels and in interstitial tissues, and w as demonstrated immunohistochemically to be composed of TTR but not am yloid A (AA) and not amyloid L (AL) proteins. The serum EC-SOD content of the patient was 10 fold higher than those seen often in other FAP patients and in healthy controls. Genetic analysis demonstrated the si ngle amino acid substitutions in Val30Met TTR and Arg213Gly EC-SOD, Si nce these data suggest the dissociation of EC-SOD from the vascular wa ll, massive amyloid deposition in the present case may be related to i ncreased oxidative stress in loco. Copyright (C) 1998 by W.B. Saunders Company.