Clinical Follow-Up of 54 Patients with IgM-Nephropathy

Abstract

The clinical course of mesangial glomerulopathy with IgM deposits (IgM-nephropathy) was studied in 54 patients. The initial manifestations of the disease were nephrotic syndrome in 18, proteinuria in 21, proteinuria together with hematuria in 4 and isolated hematuria in 11 patients. The nephrotic syndrome was steroid-responsive in 60% of cases and of these 80% were steroid-dependent. During a 5-year postbiopsy follow-up 3 patients went into terminal uremia and in 6 more patients a milder renal insufficiency was observed. Three patients were rebiopsied and in 2 of these the second biopsy specimen disclosed typical focal and segmental glomerulosclerosis. Hematuria was a favorable sign, as no patient with hematuria showed progressive impairment of renal function. The prevalence of hypertension in the whole material was 37%. At close of follow-up 35% of all patients were in clinical remission. It is suggested that IgM-nephropathy associated with abundant proteinuria or the nephrotic syndrome represents a distinct disorder from that associated with hematuria. While the nephrotic type often manifested itself with a morphologic change and a tendency to develop renal insufficiency, the hematuric type showed female predominance, a high tendency to spontaneous clinical remission and a favorable clinical course.

Discordant Evolution of Asymptomatic Proteinuria in Identical Twins

“…There is still controversy about whether IgM nephropathy, MCD, and FSGS are individual entities or different aspects of the same disease [5, 6, 7, 8, 9]. However, pathologists usually separate the three conditions according to morphological criteria.…”

“…Although the most frequent finding by light microscopy is a mild mesangial hyperplasia, normal morphology or one with only minimal abnormalities is also a common finding. Ultrastructural examination shows electron-dense deposits in the mesangial area in about 50% of cases [8]. …”

“…Controversy still exists about whether minimal change disease (MCD), IgM nephropathy and FSGS are discrete disease entities or different aspects of the same disease [5, 6, 7, 8, 9]. In fact, mesangial IgM deposition is not a specific feature of IgM nephropathy, which may be associated with a spectrum of morphological appearances, varying from minimal glomerular lesions to focal sclerosis.…”

IgM nephropathy; can we still ignore it

“…However it has been noted that males are more commonly affected than females when the presentation is Nephrotic syndrome (NS), whereas females usually present with hematuria or sub-nephrotic proteinuria. Hypertension is roughly noted in up to 30% of the patients (8,11,20,23,(32)(33) (table 2).…”

“…Unfortunately only one third of the patients, mainly with MCD/unremarkable glomerular morphology respond to steroids. Calcineurin inhibitors and Rituximab have been tried in limited studies and have shown favorable short term response (8,11,(31)(32)(33)(34)(35). However therapeutic strategies targeting suppressor T-cells and cell therapies should be tried in these patients.…”