focal glomerulosclerosis
Introduction
Introduction to focal glomerulosclerosis Focal glomerulosclerosis (focalglomeruloscerosis) refers to a type of glomerular capillaries in which glomerular capillary vasospasm has focal segmental sclerosis or hyaline degeneration without obvious cell proliferation. Can be used as mesangial hyperplasia, mesangial IgM deposition and focal glomerular sclerosis, but minimally pathological nephropathy is resistant to steroids and the consequences of repeated episodes of chronic progression. There is also an early renal biopsy of primary nephrotic syndrome that is ineffective against hormones, which is focal glomerular sclerosis. Therefore, there is still debate about whether the disease is an independent glomerular disease. However, from a clinical pathological type that is different from other kidney diseases, it can also be regarded as an independent disease, which is more common and has a tendency to increase gradually. basic knowledge The proportion of illness: 0.08% Susceptible people: mainly young people, more common in men Mode of infection: non-infectious Complications: nephrotic syndrome
Cause
The cause of focal glomerulosclerosis
Etiology
Secondary focal glomerulosclerosis (45%):
1, glomerular diseases, heroin-related nephropathy, tumor-associated nephropathy, diabetes, AIDS, hereditary nephritis, IgA nephropathy, pre-eclampsia and Hodgkin's disease.
2, renal tubules, interstitial and vascular disease reflux nephropathy, radiation nephritis, analgesic nephropathy and sickle cell disease.
3, other kidney hypoplasia, obesity and senile.
Primary focal glomerulosclerosis (10%):
The cause is unknown.
Pathogenesis
It is still unclear that most of the changes in glomerular hemodynamics or damage to the basement membrane lead to the extracellular uptake of macromolecular substances by the mesangial tissue, resulting in glomerular sclerosis. Human mesenchymal nephron embryos are early and bulky. Higher filtration rate, capillary intravascular hypertension, high filtration eventually lead to structural damage, the disease near the myeloid nephropathy appears early and severe, due to segmental glomerular epithelial cell damage, the anion electricity on the basement membrane Impaired barrier, chronic proteinuria overload, sustained high filtration, high perfusion will eventually lead to glomerular sclerosis, glomerular hypertrophy and foam cell formation are important in the formation and development of this disease, in 5/6 nephrectomy In the animal model, glomerular capillary blood flow and pressure increased, glomerular epithelial cells were significantly damaged, residual nephron hyperfunction, leading to hyaline degeneration, Fogo et al. will be primary focal glomerulosclerosis After the pathophysiology and clinical connection, the average glomerular area of adults and children with this disease was significantly larger than that of the same age. The repeated renal biopsy also confirmed that some of the disease were initially When there is a small lesion, there is obvious glomerular hyperplasia. In addition, foam cells are found in the glomeruli of many patients with primary focal glomerulosclerosis, which has the characteristics of macrophage histogenesis. It can be transformed by circulating monocytes or mesangial cells. Some cytokines and growth factors such as IL-1, -TNF, IL-6 play a role in causing glomerular sclerosis, and animal experiments have found that Serum cholesterol levels are associated with the degree of sclerosis.
Immune damage is also involved in the occurrence and development of this disease. IgM and C3 particle-like deposition can be seen in the glomerular sclerosis area in immunopathology. Electron microscopy shows that there is a large amount of electron dense deposit in the sclerotic lesion, and the disease is easy to recur in kidney transplantation.
Prevention
Focal glomerulosclerosis prevention
Related to a variety of factors:
1 urine protein level: urine protein > 10 g / 24 hours, the disease progresses rapidly, more than 6 years of renal function loss; urine protein 3 ~ 3.5g / 24h, 50% 6 ~ 8 years into end-stage uremia , <3g/24h, renal function remained at normal levels after 10 years.
2 renal disease remission or not - treatment response: those who are sensitive to hormones rarely develop to renal failure, complete remission, the incidence of end-stage renal failure is 15%, and incomplete remission is 85%.
3 Age: Adults are relatively good. The incidence and recurrence rate of nephrotic syndrome are reported to be 55% and 15% in adults, and 76% and 80% in children.
4 races: Ingulli et al. found that the incidence of blacks in children with nephrotic syndrome was higher than that of whites, and that they developed rapidly. 78% of blacks developed end-stage uremia within 8.5 years, and only 33% of whites were in the same period of time.
5 course of disease and the degree of hypertension: at the time of treatment, the stage of the disease was late, the prognosis of patients with severe hypertension was poor, 6 renal histopathology: severe damage or membranous, mesangial proliferative and vascular damage easily enter renal failure.
Complication
Focal glomerulosclerosis complications Complications nephrotic syndrome
The disease with nephrotic syndrome is not only hypercoagulopathy, but also intrarenal coagulation, balloon adhesion.
Symptom
Symptoms of focal glomerulosclerosis Common symptoms Nephrotic syndrome Hypertension Glomerulosclerosis Hematuria Renal glomerular hyperplasia proteinuria
The disease can occur at any age, mainly in young people, males are more common, all of which are persistent non-selective proteinuria. Typical cases are mostly caused by nephrotic syndrome, accounting for about 50%, accounting for the majority of primary nephropathy. Signs 5% to 20%, 50% to 60% of patients have hematuria, hypertension and renal dysfunction reported differently, ranging from 10% to 50%, clinical manifestations, especially urine protein levels and prognosis.
Examine
Examination of focal glomerulosclerosis
an examination:
The diagnosis of this disease mainly depends on renal biopsy: some segments of glomeruli are visible under light microscope, and the unhardened parts are relatively normal. The typical lesions in the hardened area can be seen as a large number of cell-free matrix and transparent. Sample material
PAS staining was positive: capillary collapse, foam cell formation and local epithelial cell hyperplasia, adhesion of glomeruli to the bursal sac, located at the junction of the pith and the first ball, in the non-hardened area, glomerular capillary epithelium Cell swelling, hyperplasia, vacuolar degeneration and larger PAS-positive granules in the cytoplasm, corresponding tubular atrophy and renal interstitial fibrosis, focal distribution;
Immunofluorescence: IgM and C3 deposits are often seen in the hardened area; electron microscopy: hardened lesions have large electron dense deposits, and non-hardened areas of capillary vasospasm show extensive epithelial cell foot processes fusion and regression. When the lesions are severe, epithelial cells can Separated from the base film and peeled off.
Diagnosis
Diagnosis and diagnosis of focal glomerulosclerosis
The diagnosis of this disease mainly depends on renal biopsy.
Differential diagnosis
1 Minimal lesion nephropathy (MCD): may be misdiagnosed due to insufficient tissue or lack of access to the paramedullary nephron, but MCD rarely shows hypertension and hematuria. Most patients are sensitive to hormone therapy, and the following pathological features are helpful. The difference between MCD and FSGS:
1 The glomerular volume of the former is increased, while the glomerular volume of the latter is different;
2 The former is characterized by diffuse foot process fusion, while the latter is segmental;
3 The latter can be seen in the vacuolar degeneration of visceral epithelial cells.
2 Secondary: FSGS secondary FSGS caused by other diseases in addition to the characteristics of the primary disease, its histological features include: glomerular sclerosis degree, renal tubular wall thickening, perivascular fibrosis Interstitial lesions in the tubules are patchy, and a large number of inflammatory cell infiltrates are also seen in the interstitial. These histological differential diagnoses have great defects. Essentially, they do not rely on medical history, and clinical manifestations and laboratory tests are difficult to do. The correct differential diagnosis, especially primary and secondary FSGS, cannot be distinguished by histomorphological features. Therefore, some people have recently proposed that the surface markers of visceral epithelial cells such as Cytokeratins can help us distinguish according to the characteristics of FSGS. Primary and secondary FSGS.
