Background: Familial amyloidosis (Finnish type) is an autosomal dominantly inherited disorder that can result in the complication of corneal lattice opacity caused by corneal amyloidosis. Since familial amyloidosis (Finnish type) is a very rare disease in Japan, detailed reports on corneal amyloidosis of familial amyloidosis (Finnish type) confirmed by genetic studies are so far available only for four families. Here, we report two families showing corneal amyloidosis associated with familial amyloidosis (Finnish type).
Case presentation: Cases 1-3 from family 1 and case 4 from family 2 were diagnosed as corneal amyloidosis associated with familial amyloidosis (Finnish type) based on the results of gelsolin genetic testing. Anterior segment optical coherence tomography findings suggested that in corneal amyloidosis associated with familial amyloidosis (Finnish type), lattice opacities may be present in the Bowman layer to superficial stroma layer of the cornea. All patients exhibited corneal lattice opacity and neuropathy; blepharoptosis caused by cutis laxa was seen in three patients, and renal disorders were observed in two patients. Facial nerve palsy and decreased sweating were present owing to neuropathy in all cases. Gelsolin genetic testing revealed heterozygous condition for the mutation c.640G>A (p.Asp214Asn) in all cases, which agrees with the results previously reported in Japan.
Conclusion: When corneal lattice opacity, mask-like face, and neuropathy are present simultaneously, genetic testing for familial amyloidosis (Finnish type) may be useful for establishing a diagnosis.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 125: 30-37, 2021.