Membranoproliferative glomerulonephritis (MPGN) (synonyms: Glomerulonephritis, membranoproliferative; Membranoproliferative glomerulonephritis; ICD-10-GM N05.5: Unspecified nephritic syndrome: Diffuse mesangiocapillary glomerulonephritis) is a rare disease of the glomeruli (renal corpuscles). The basement membrane is thickened and splintered. In addition, the mesangial cells (mesangium is a specialized tissue structure in the renal corpuscles of the kidney) grow and immune complexes are deposited. It is divided into immune complex-mediated and complement-mediated MPGN.
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 – 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
An idiopathic (with no apparent cause) form is distinguished from a secondary form (in the context of infectious diseases such as hepatitis B or C, autoimmune diseases such as systemic lupus erythematosus (SLE), malignant (malignant) diseases such as lymphoma, and others).
The following types of membranoproliferative glomerulonephritis (MPGN) can be distinguished:
- Type 1 – 80% of cases; formation of subendothelial and mesangial complement depots.
- Type 2 – here complement depots are also formed in the basement membrane.
- Type 3 and 4 – very rare
Frequency peak: idiopathic form occurs predominantly between the ages of 8 and 30 years.
Course and prognosis: membranoproliferative glomerulonephritis may progress with a nephritic syndrome (hematuria (blood in the urine), hypertension (high blood pressure), and limitation of renal function) or a nephrotic syndrome. Nephrotic syndrome is characterized by proteinuria (increased excretion of protein in the urine), resulting hypoproteinemia (too little protein in the blood), as well as hyperlipoproteinemia (lipid metabolism disorder) and edema (water retention). In 50% of cases, membranoproliferative glomerulonephritis is associated with nephrotic syndrome.Overall, the prognosis is rather unfavorable. In the idiopathic form, 50% of affected individuals become dialysis-dependent within 10 years.
