Gelsolin-related familial amyloidosis, Finnish type, in a Portuguese family: clinical and neurophysiological studies.

We report a Portuguese family with familial amyloid polyneuropathy related to gelsolin. There were no known Finnish ancestors, but the same mutation as described in Finnish patients (G654A) was carried. Clinical and neurophysiological investigations were performed in four patients. Corneal lattice dystrophy affected all four patients; an axonal lesion of the facial nerve occurred in three patients; visual tract involvement was documented in one case; and corticospinal and posterior column dysfunction was present in one patient. Polarizing microscopy of skin and muscle samples demonstrated amyloid deposits in two patients; anti-gelsolin immunohistochemistry was positive for amyloidogenic gelsolin. The Finnish mutation of gelsolin protein (G654A) was detected in five family members. The utility of neurophysiological testing in the evaluation and follow-up of this type of amyloidosis is discussed.