ABSTRACT
A German woman presented with proteinuria and haematuria aged 49, and was found to have amyloidosis on renal biopsy. Her biopsy showed extensive amyloid localized solely to the glomeruli, a characteristic distribution that suggested fibrinogen A. DNA analysis confirmed that the patient was heterozygous for a novel missense mutation in the fibrinogen A encoding the variant Glu540Val, and the renal amyloid deposits stained specifically with antibodies to fibrinogen. The mutation was present in two of the sisters’ three children, none of whom have any evidence of renal dysfunction. None of the subjects with fibrinogen A chain Glu540Val had evidence of neuropathy, cardiac amyloidosis or any sign of extra-renal amyloid involvement other than in the spleen, which was imaged on SAP scintigraphy in both the proband and her sister. This newly discovered mutation is in the same region of exon 5 that contains the five other known amyloidogenic fibrinogen A.
