What is the pathology of lupus nephritis

What everyone should know is that even the same disease has classifications. Similarly, for different classifications, of course the causes and symptoms are different, and what patients and doctors need to do is to have a detailed understanding, so that they can find treatment methods based on specific circumstances and help patients get rid of the troubles caused by the disease as soon as possible. So, what is the pathology of lupus nephritis? Let’s learn about it together.

1. Glomerular sclerosis

The lesions are mainly glomerular sclerosis, while other lesions are absent. ,

2. Mesangial glomerulonephritis

The lesions are confined to the mesangial area, and may show no structural abnormalities under light microscopy (type IIa) or may appear as proliferation of mononuclear cells or mesangial cells in the mesangial area (type IIb). Immunofluorescence showed IgG, C3, C4, C1q in the mesangial area. A few IgA and IgM were seen as granular deposits, and IgG was occasionally seen as linear deposits. Electron microscopy revealed electron-dense deposits in the mesangial region and segmental disappearance of the foot processes of glomerular epithelial cells. This type often does not have abnormalities of the renal tubules, interstitium, and blood vessels.

3. Focal segmental proliferative glomerulonephritis

This type is common, accounting for about 30%. Under light microscopy, more than half of the glomeruli are normal despite mesangial lesions, while the diseased glomeruli show segmental cell proliferation, which may be accompanied by cell necrosis. Immunofluorescence examination showed a small amount of IgG, IgM, IgA, C1q, C3, and C4 in the mesangial area and capillary walls, and properdin was deposited in granular form. Electron microscopy revealed electron-dense deposits in the subendothelial and mesangial regions.

4. Membranous lupus nephritis

Less common. The microscopic findings may be similar to those of idiopathic membranous glomerulonephritis (Va), diffuse mesangial lesions (Vb), focal cell proliferation and sclerosis (Vc), or diffuse proliferative nephritis changes (Vd). Immunofluorescence showed that IgG, IgM, IgA, C1q, C4, C3, C5-9 were deposited in granular form along the capillary walls, with IgG and C1q being the most common, and can also be seen in the mesangial area. Electron microscopy revealed electron-dense deposits in the mesangial area, subendothelial area, and tubular interstitium, all of which suggested a diagnosis of lupus nephritis.

5. Diffuse proliferative glomerulonephritis

The most serious and common, accounting for more than half. Under the light microscope, almost all glomeruli have severe changes, manifested as proliferation of mesangial cells and endothelial cells, aggregation of leukocytes, degenerative changes in many cells, insertion of mesangial cells between the basement membrane and endothelial cells, and formation of crescents. This type may present with "wire coil-like lesions and hematoxylin bodies, often indicating the diagnosis of lupus nephritis. In addition, transparent thrombi may occur. Immunofluorescence examination can show IgG, IgM, IgA, C1q, C3, C4, C5-9 in all areas of the glomerulus. A few may have granular IgE deposition, especially under the endothelium. Electron microscopy shows significant electron-dense deposition, mainly in the subendothelium and mesangium.

6. Normal glomerular type

This type is extremely rare, with no abnormalities in the glomerular tissue structure and no immune complex deposition.

7. Vascular abnormalities and tubulointerstitial inflammation

Vascular abnormalities are varied, with typical hypertensive arterial and arteriolar changes being the most common, mainly in arterioles and afferent arterioles, manifested by plasma protein aggregation in the vessel wall, endothelial cell swelling and destruction, lumen stenosis and blockage, and necrotizing arteritis being rare. Renal interstitial inflammatory cell infiltration is common, often accompanied by tubular atrophy and necrosis, thickening of the tubular basement membrane, and deposition in the interstitium, tubular basement membrane, and peritubular capillaries. These extraglomerular deposits are often associated with the activity of glomerular lesions and the severity of glomerular cell proliferation.

The pathology of lupus nephritis has been introduced in detail above. I hope to help some patients understand the specific situation of lupus nephritis in time. I also remind patients that if they find themselves suffering from this disease, they must go to the hospital for examination in time and receive treatment according to the doctor's guidance so that they can recover as soon as possible.