Mesangial IgA glomerulonephritis or IgA nephropathy (IgAN) (synonyms: IgA nephritis (IgAN); Berger’s disease; glomerulonephritis, mesangial IgA-; IgA glomerulonephritis; ICD-10-GM N05.3: Unspecified nephritic syndrome: diffuse mesangioproliferative glomerulonephritis) is associated with the deposition of immunoglobulin A (Ig A) in the mesangium (intermediate tissue) of the glomeruli.
The following main forms of glomerulonephritis are distinguished:
- Minimal-change glomerulonephritis (MCGN) (glomerular minimal lesion) – most common cause of nephrotic syndrome in childhood.
- Focal segmental sclerosing glomerulonephritis (FSSGN) – associated with nephrotic syndrome in approximately 15% of cases.
- Membranous glomerulonephritis (MGN) – the most common cause of nephrotic syndrome in adults; accounts for 20-30% of all glomerulonephritides; may be primary or secondary (resulting from other diseases)
- Membranoproliferative glomerulonephritis (MPGN) – associated with nephrotic syndrome in 50%.
- Mesangial IgA glomerulonephritis (IgA nephropathy, IgAN) – most common form with up to 35% of cases.
- Rapid progressive glomerulonephritis (RPGN) – occurs in 2-7% of patients; the disease is classified into several causative groups
Sex ratio: males to females is 2-3: 1.
Frequency peak: the disease occurs predominantly between the 20th and 30th year of life.
In Germany, France and Japan, mesangial IgA glomerulonephritis accounts for up to 35% of the total number of glomerulonephritis. In England, Canada, and the United States, this form is relatively rare, accounting for up to 10%.
The incidence (frequency of new cases) is about 8-40 cases per 1,000,000 inhabitants per year (Western Europe).
Course and prognosis: The course of the disease is accompanied by hypertension (high blood pressure), persistent proteinuria (protein in the urine) and impaired kidney function. Progressive (progressive) loss of renal function occurs in 20-30%. In one study, serum uric acid concentration was shown to be directly proportional to the rate of decline in renal function in patients with mesangial IgA glomerulonephritis (IgA nephritis).
