IgA myeloma presenting as Henoch-Schönlein purpura with nephritis.
IgA nephropathy (IgAN) and Henoch-Schönlein purpura (HSP) are both characterized by IgA-mediated tissue injury, including mesangial proliferative glomerulonephritis. Abnormalities of IgA1 glycosylation are described in IgA nephropathy and HSP nephritis. IgA-antineutrophil cytoplasmic antibodies (ANCA) have been inconsistently described in the serum of patients with HSP. In IgA myeloma, the paraprotein-mediated renal lesion is typically cast nephropathy; IgAN or HSP have only rarely been reported in myeloma even when an IgA paraprotein is circulating in large concentrations. We report the case of a 50-year-old man with IgA myeloma who presented with HSP including nephritis and rapidly progressive renal failure. His IgA1 had altered O-glycosylation in the pattern seen in IgAN and also contained an IgA-ANCA. This case adds further weight to the evidence that IgA1 O-glycosylation abnormalities predispose to mesangial IgA deposition and also that IgA-ANCA may have a pathogenic role in the development of HSP.
Zickerman
A M
AM
Departments of Nephrology and Pathology, Leicester General Hospital, United Kingdom.
Allen
A C
AC
Talwar
V
V
Olczak
S A
SA
Brownlee
A
A
Holland
M
M
Furness
P N
PN
Brunskill
N J
NJ
Feehally
J
J
D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood; D006031:Glycosylation; D006801:Humans; D011695:IgA Vasculitis / Q000209:etiology*; D007070:Immunoglobulin A / Q000097:blood*; D007136:Immunoglobulins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000150:complications* / Q000276:immunology; D009194:Myeloma Proteins; D009393:Nephritis / Q000209:etiology*
D019268:Antibodies, Antineutrophil Cytoplasmic; D007070:Immunoglobulin A; D007136:Immunoglobulins; D009194:Myeloma Proteins; C017551:myeloma immunoglobulins