BACKGROUND AND OBJECTIVES: X-linked Alport syndrome (X-AS) is caused by mutations of the COL4A5 gene, which encodes for the collagen IV α5 chain (α5[COLIV]), resulting in structural and functional abnormalities of the glomerular basement membrane (GBM) and leading to CKD. The aim of the present study was to evaluate the prognostic value of residual collagen IV chain expression in the GBM of patients with X-AS. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The medical records of 22 patients with X-AS from 21 unrelated families collected between 1987 and 2009 were reviewed (median age at last follow-up, 19.9 years; range, 5.4-35.1 years); GBM expression of α1, α3, and α5(COLIV) chains was assessed by immunofluorescence microscopy. RESULTS: GBM distribution of the α5(COLIV) chain was diffuse in 1 and segmental or absent in 21 of the 22 patients; the expression of the α3(COLIV) chain was diffuse in 5 of 22 patients and segmental or absent in 17 of 22 patients. Patients with diffuse staining for the α3(COLIV) chain presented with proteinuria significantly later (median age, 16.9 versus 6.1 years; P=0.02) and reached an estimated GFR < 90 ml/min per 1.73 m(2) at an older age (median age, 27.0 versus 14.9 years; P=0.01) compared with patients with segmental or absent staining. Two thirds of patients with abnormal α3(COLIV) expression by immunofluorescence studies had null or truncating COL4A5 mutations, as opposed to none of the 4 tested patients with diffuse α3(COLIV) chain glomerular distribution. CONCLUSIONS: These results indicate that maintained expression of the α3(COLIV) chain is an early positive prognostic marker in patients with X-linked Alport symdrome.
BACKGROUND AND OBJECTIVES:X-linked Alport syndrome (X-AS) is caused by mutations of the COL4A5 gene, which encodes for the collagen IV α5 chain (α5[COLIV]), resulting in structural and functional abnormalities of the glomerular basement membrane (GBM) and leading to CKD. The aim of the present study was to evaluate the prognostic value of residual collagen IV chain expression in the GBM of patients with X-AS. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The medical records of 22 patients with X-AS from 21 unrelated families collected between 1987 and 2009 were reviewed (median age at last follow-up, 19.9 years; range, 5.4-35.1 years); GBM expression of α1, α3, and α5(COLIV) chains was assessed by immunofluorescence microscopy. RESULTS: GBM distribution of the α5(COLIV) chain was diffuse in 1 and segmental or absent in 21 of the 22 patients; the expression of the α3(COLIV) chain was diffuse in 5 of 22 patients and segmental or absent in 17 of 22 patients. Patients with diffuse staining for the α3(COLIV) chain presented with proteinuria significantly later (median age, 16.9 versus 6.1 years; P=0.02) and reached an estimated GFR < 90 ml/min per 1.73 m(2) at an older age (median age, 27.0 versus 14.9 years; P=0.01) compared with patients with segmental or absent staining. Two thirds of patients with abnormal α3(COLIV) expression by immunofluorescence studies had null or truncating COL4A5 mutations, as opposed to none of the 4 tested patients with diffuse α3(COLIV) chain glomerular distribution. CONCLUSIONS: These results indicate that maintained expression of the α3(COLIV) chain is an early positive prognostic marker in patients with X-linked Alport symdrome.
Authors: P Barsotti; A O Muda; G Mazzucco; L Massella; B Basolo; M De Marchi; G Rizzoni; G Monga; T Faraggiana Journal: Nephrol Dial Transplant Date: 2001-05 Impact factor: 5.992
Authors: D F Barker; S L Hostikka; J Zhou; L T Chow; A R Oliphant; S C Gerken; M C Gregory; M H Skolnick; C L Atkin; K Tryggvason Journal: Science Date: 1990-06-08 Impact factor: 47.728
Authors: A Renieri; M Seri; L Galli; P Cosci; E Imbasciati; L Massella; G Rizzoni; G Restagno; A O Carbonara; E Stramignoni Journal: Hum Genet Date: 1993-10 Impact factor: 4.132
Authors: Jean Philippe Jais; Bertrand Knebelmann; Iannis Giatras; Mario De Marchi; Gianfranco Rizzoni; Alessandra Renieri; Manfred Weber; Oliver Gross; Kai-Olaf Netzer; Frances Flinter; Yves Pirson; Karin Dahan; Jörgen Wieslander; Ulf Persson; Karl Tryggvason; Paula Martin; Jens Michael Hertz; Cornelis Schröder; Marek Sanak; Maria Fernanda Carvalho; Juan Saus; Corinne Antignac; Hubert Smeets; Marie Claire Gubler Journal: J Am Soc Nephrol Date: 2003-10 Impact factor: 10.121
Authors: Samar M Said; Mary E Fidler; Anthony M Valeri; Brooke McCann; Wade Fiedler; Lynn D Cornell; Mariam Priya Alexander; Ahmed M Alkhunaizi; Anne Sullivan; Carl H Cramer; Marie C Hogan; Samih H Nasr Journal: Kidney Int Rep Date: 2016-09-29