IgM associated primary diffuse mesangial proliferative glomerulonephritis.

Abstract

Twenty-three cases of IgM associated primary diffuse mesangial proliferative glomerulonephritis are presented. In 18, IgM was the sole localising host immunoglobulin, and it was the predominant globulin in five; C3 was also present in 18. Light microscopy revealed variable diffuse and global mesangial proliferation in all cases, with additional focal global sclerosis in 16, focal segmental sclerosis in 15, and small capsular crescents in seven. Material for electron microscopy was available from 19 patients; in 13, occasional intramesangial electron dense deposits were identified, and in 18 there were irregular, rather ill defined areas of increased electron density in mesangial regions. Clinically, 14 patients presented with the nephrotic syndrome, and nine had asymptomatic proteinuria. During follow-up, only 10 patients showed no change in renal function or improved; the remainder showed increasing hypertension and/or renal function deterioration and four developed end stage renal failure. It is suggested that IgM associated mesangial proliferative glomerulonephritis should be considered as a distinct clinicoimmunopathological entity.

IgM Contributes to Glomerular Injury in FSGS

“…3 Patients with mesangial expansion or mesangial proliferation by light microscopy frequently have abundant glomerular IgM deposition. 4 Glomerular IgM is also observed in many secondary forms of glomerulosclerosis, including diabetic nephropathy 5 and hypertensive nephropathy. 6 Importantly, C3 and C4 are frequently detected in the glomeruli of patients who have IgM deposits.…”

“…6 Importantly, C3 and C4 are frequently detected in the glomeruli of patients who have IgM deposits. 4,7,8 In spite of its promiscuous presence in glomerular lesions, a pathogenic role for glomerular IgM has not been demonstrated. Some series, however, have shown that the presence of IgM is of prognostic significance.…”

IgM nephropathy; can we still ignore it

“…Most of the studies have reported on prevalence of IgMN as frequency/ percentage of renal biopsies with diagnosis of IgMN reported from 2 % to 18.5 % in native biopsies (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13). Occasional cases of IgMN in transplant biopsies have also been reported (14).…”

Clinical Profile &Treatment Outcome in Children with IgM Nephropathy

“…Glomeruli show diverse grade of mesangial hypercellularity or no changes by light microscopy [1] . However, recent edition of Heptinstall's pathology of the kidney (7 TH edition) defines IgMN as cases with bright staining (at least two positive out of three) and with demonstrable mesangial deposits on electron microscopy.…”

“…Two articles published in 1978 by independent groups [4,5] are considered by many authors to be the first descriptions of a glomerulopathy characterised by diffuse mesangial deposits of immunoglobulin M (IgM) in patients with relatively normal light microscopy. The disease, like IgA nephropathy (IgAN), is defined by its immunohistologic features: the presence of IgM as the sole or dominant immunoglobulin in the mesangial regions of the glomeruli in a diffuse (all glomeruli) and global (the entire glomerulus) distribution [4][5][6][7] . Its incidence varies, in accordance with different series, between 4.8% and 8.6% of all renal biopsies, affecting all ages and without predilection for gender [6,8,9,10] .…”