Fibrinogen A alpha-chain amyloidosis: report of the first case in Latin America.
BACKGROUND
Hereditary fibrinogen A alpha-chain (AFib) amyloidosis affects different organs, especially the kidneys. No case of this disease has been reported in Latin America.


METHODS
A 52-year-old previously healthy Brazilian woman presented with a seven-month history of proteinuria in the absence of hematuria. The patient had normal blood pressure and reported no other symptoms. A renal biopsy was obtained and light microscopy revealed the presence of Congo red positive deposits (apple-green birefringence under polarized light) only in the glomerular compartment. These deposits were strongly immunoreactive to fibrinogen in all glomeruli. Electron microscopy showed the presence of organized deposits compatible with AFib. The diagnosis was confirmed by DNA analysis of the AFib gene, which demonstrated a Glu526Val mutation in one allele.


CONCLUSIONS
This first description of hereditary AFib amyloidosis in Latin America highlights the need to include this type of amyloidosis in the differential diagnosis, especially in Brazil where the degree of miscegenation is high.
Nephropathology Service, Federal University of Triângulo Mineiro, Uberaba, Brazil.
Juliana Reis
JR
Machado
Marcos Vinícius da
MV
Silva
Precil Diego Miranda de Menezes
PD
Neves
Flavia Aparecida de
FA
Oliveira
Rosana Rosa Miranda
RR
Corrêa
Willians Vinícius Dutra
WV
Rodrigues
Merril
M
Benson
Marlene Antônia Dos
MA
Reis
D000682:Amyloid / Q000235:genetics*; D028226:Amyloidosis, Familial / Q000150:complications / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D001938:Brazil; D005260:Female; D005340:Fibrinogen / Q000235:genetics*; D006801:Humans; D007678:Kidney Glomerulus / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D009154:Mutation; D011507:Proteinuria / Q000150:complications / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology
D000682:Amyloid; C464794:fibrinogen Aalpha; D005340:Fibrinogen