Objective: To summary the clinical presentation and prognosis of primary nephrotic syndrome (PNS) in teenagers. Methods: The clinical data, renal pathological types and prognosis of 118 children over 10-year-old with PNS treated in the Department of Nephrology of the Children's Hospital Affiliated to Capital Institute of Pediatrics from January 2010 to December 2020 were retrospectively analyzed, with 408 children ≤10-year-old as control group synchronously. Chi-square test was used to compare the difference of clinical types, pathologic types, response to steroids and tubulointerstitial changes between the groups. The teenagers with steroid resistant nephrotic syndrome (SRNS) were divided into initial non-responder group and late non-responder group. Kaplan-Meier method was used to compare the difference of persistent proteinuria, and Fisher's exact test for the histological types. Results: There were 118 children >10-year-old, including 74 males and 44 females, with the onset age of 12.1 (10.8, 13.4) years; and 408 children ≤10-year-old with the onset age of 4.5 (3.2, 6.8) years. The proportion of SRNS was significantly higher in patients >10-year-old than those ≤10-year-old (24.6% (29/118) vs. 15.9% (65/408), χ²=4.66, P=0.031). There was no statistical difference in the pathological types between >10-year-old and ≤10-year-old (P>0.05), with minimal change disease the most common type (56.0% (14/25) vs. 60.5% (26/43)). The percentage of cases with renal tubulointerstitial lesions was significantly higher in children >10-year-old compared to those ≤10-year-old (60.0% (15/25) vs. 23.3% (10/43), χ²=9.18, P=0.002). There were 29 cases presented with SRNS in PNS over 10-year-old, including 19 initial non-responders and 10 late non-responders. Analyzed by Kaplan-Meier curve, it was shown that the percentage of persistent proteinuria after 6 months of immunosuppressive treatments was significantly higher in initial non-responders than those of the late non-responders ((22±10)% vs. 0, χ²=14.68, P<0.001); the percentage of minimal change disease was significantly higher in patients of late non-responders than those of the initial non-responders (5/6 vs. 3/13, P=0.041). Of the 63 >10-year-old with steroid-sensitive nephrotic syndrome followed up more than one year, 38 cases (60.3%) had relapse, and 14 cases (22.2%) were frequent relapse nephrotic syndrome and steroid dependent nephrotic syndrome. Among the 45 patients followed up over 18-year-old, 22 cases (48.9%) had recurrent proteinuria continued to adulthood, 3 cases of SRNS progressed to kidney insufficiency, and one of them developed into end stage kidney disease and was administrated with hemodialysis. Conclusions: Cases over 10-year-old with PNS tend to present with SRNS and renal tubulointerstitial lesions. They have a favorable prognosis, but are liable to relapse in adulthood.
Male ; Female ; Adolescent ; Child ; Humans ; Nephrotic Syndrome/pathology* ; Retrospective Studies ; Nephrosis, Lipoid/drug therapy* ; Prognosis ; Proteinuria/etiology* ; Recurrence

Nephrotic syndrome (NS) is the most common glomerular disorder in childhood, and a vast majority of cases are idiopathic. The precise cause of this common childhood disease is not fully elucidated despite significant advancements in our understanding of podocyte biology. Idiopathic NS has been considered “a disorder of T-cell function” mediated by a circulating factor that alters podocyte function resulting in massive proteinuria since the last four decades. Several circulatory factors released from T-cells are considered to be involved in pathophysiology of NS; however, a single presumptive factor has not been defined yet. Extended evidence obtained by advances in the pathobiology of podocytes has implicated podocytes as critical regulator of glomerular protein filtration and podocytopathy. The candidate molecules as pathological mediators of steroid-dependent NS are CD80 (also known as B7-1), hemopexin, and angiopoietin-like 4. The “two-hit” hypothesis proposes that the expression of CD80 on podocytes and ineffective inhibition of podocyte CD80 due to regulatory T-cell dysfunction or impaired autoregulation by podocytes results in NS. Recent studies suggest that not only T cells but also other immune cells and podocytes are involved in the pathogenesis of MCNS.
Biology ; Filtration ; Hemopexin ; Homeostasis ; Nephrosis, Lipoid ; Nephrotic Syndrome ; Pathology ; Podocytes ; Proteinuria ; T-Lymphocytes

Focal segmental glomerulosclerosis (FSGS) is characterized by focal and segmental obliteration of glomerular capillary tufts with increased matrix. FSGS is classified as collapsing, tip, cellular, perihilar and not otherwise specified variants according to the location and character of the sclerotic lesion. Primary or idiopathic FSGS is considered to be related to podocyte injury, and the pathogenesis of podocyte injury has been actively investigated. Several circulating factors affecting podocyte permeability barrier have been proposed, but not proven to cause FSGS. FSGS may also be caused by genetic alterations. These genes are mainly those regulating slit diaphragm structure, actin cytoskeleton of podocytes, and foot process structure. The mode of inheritance and age of onset are different according to the gene involved. Recently, the role of parietal epithelial cells (PECs) has been highlighted. Podocytes and PECs have common mesenchymal progenitors, therefore, PECs could be a source of podocyte repopulation after podocyte injury. Activated PECs migrate along adhesion to the glomerular tuft and may also contribute to the progression of sclerosis. Markers of activated PECs, including CD44, could be used to distinguish FSGS from minimal change disease. The pathogenesis of FSGS is very complex; however, understanding basic mechanisms of podocyte injury is important not only for basic research, but also for daily diagnostic pathology practice.
Actin Cytoskeleton ; Age of Onset ; Capillaries ; Diaphragm ; Epithelial Cells ; Foot ; Glomerulosclerosis, Focal Segmental* ; Nephrosis, Lipoid ; Pathology ; Permeability ; Podocytes ; Rabeprazole ; Sclerosis ; Wills

Minimal change disease (MCD) is a common pathological type of nephrotic syndrome. Its main histology is the fusion of podocyte foot process. The pathogenesis of MCD is not clear, but previously it was thought to be related to immune mechanism. In recent years more studies show that podocyte injury is the key link in the pathogenesis of MCD. In MCD mouse model and human kidney tissues, the expressions of podocyte slit membrane protein-nephrin and podocin, skeleton protein-synaptopodin are decreased, and the expression of synaptopodin is correlated with the response to hormone therapy. In addition, newest studies focused on another two potocyte associated proteins, CD80 and Angiopoietin-like-4. CD80, a T cell stimulating molecule, is expressed in potocyte. Kappa B gene sequences can be activated by external microbes, antigens through acting potocytes, which can induce the upregulation of CD80 expression, cytoskeletal protein damage and the glomerular filtration rate changes, resulting in proteinuria. Angiopoietin-like-4 can be expressed in normal potocytes, but over-expression of angiopoietin-like-4 may injure the GBM charge barrier and induce the foot process fusion, leading to MCD. However, further studies on the factors inducing CD80 and Angiopoietin-like-4 expression, and the interaction between glomerular basement membrane and the two proteins are needed. Based on the mechanism of MCD, NF-kappa B inhibitors and sialylation therapy would be a novel non-immune therapy for MCD.
Angiopoietin-like 4 Protein ; Angiopoietins ; metabolism ; Animals ; B7-1 Antigen ; metabolism ; Disease Models, Animal ; Humans ; Intracellular Signaling Peptides and Proteins ; metabolism ; Kidney ; pathology ; Membrane Proteins ; metabolism ; Mice ; Microfilament Proteins ; metabolism ; NF-kappa B ; metabolism ; Nephrosis, Lipoid ; pathology ; Podocytes ; pathology

There are several reports to demonstrate that rifampicin, a major anti-tuberculosis agent, is associated with some adverse renal effects, with a few cases of rifampicin-induced minimal change disease (MCD). In the present case, a 68-year-old female presented with nausea, vomiting, foamy urine, general weakness and edema. She had been taking rifampicin for 4 weeks due to pleural tuberculosis. The patient had no proteinuria before the anti-tuberculosis agents were started, but urine tests upon admission showed heavy proteinuria with a 24-h urinary protein of 9.2 g/day, and serum creatinine, albumin, and total cholesterol levels were 1.36 mg/dL, 2.40 g/dL, and 283 mg/dL, respectively. MCD was diagnosed, and the patient achieved complete remission after cessation of rifampicin without undergoing steroid therapy.
Aged ; Antibiotics, Antitubercular/*adverse effects/therapeutic use ; Edema/etiology ; Female ; Humans ; Kidney Function Tests ; Kidney Glomerulus/pathology ; Nausea/etiology ; Nephrosis, Lipoid/*chemically induced/pathology ; Proteinuria ; Remission Induction ; Rifampin/*adverse effects/therapeutic use ; Treatment Outcome ; Tuberculosis, Pleural/*drug therapy

OBJECTIVETo investigate the prevalence of PLA2R1 in renal biopsy specimens of patients with idiopathic membranous nephropathy (IMN) and explore the relationship between PLA2R1 and IMN.

METHODSA total of 108 adult patients with biopsy-proved glomerular diseases were enrolled in this study, including 41 with IMN, 2 with hepatitis B-associated membranous nephropathy, 8 with V lupus nephritis, 27 with IgA nephropathy, 19 with minimal change nephropathy, 5 with mild mesangial proliferative glomerulonephritis, and 6 with focal segmental glomeruloselerosis (FSGS). Indirect immunofluorescence assay was used to detect PLA2R1 in the biopsy specimens and the clinical variables of the IMN patients were analyzed.

RESULTSIn 35 of the 41 (85.37%) patients with IMN, PLA2R1 was detected with a fine granular pattern in the subepithelial deposits along the glomerular capillary loops. PLA2R1 antigen was not detected in patients with other glomerulopathies. No significant differences were found in age, serum creatinine, serum albumin, or 24-h urinary protein level between PLA2R1-positive and negative patients with IMN (P>0.05).

CONCLUSIONAccording to our results, 85.37% of adult patients with biopsy-proven IMN are positive for PLA2R1 antigen, which, however, does not contribute to variations of the patients' clinical manifestations.

Adult ; Biopsy ; Glomerulonephritis, Membranous ; metabolism ; Humans ; Kidney ; metabolism ; pathology ; Kidney Function Tests ; Kidney Glomerulus ; pathology ; Nephrosis, Lipoid ; metabolism ; Receptors, Phospholipase A2 ; metabolism

OBJECTIVETo study the expression of neonatal Fc receptor in podocytes in human nephritis and immune-induced rat nephritis models: anti-Thy1.1 nephritis and Heymann nephritis.

METHODSThirty-nine cases of renal biopsies were enrolled from September 2009 to February 2010, including 8 cases of minimal change disease, 4 cases of focal segmental glomerulosclerosis, 9 cases of membranous nephropathy, 12 cases of IgA nephropathy and 6 cases of lupus nephritis. Five normal kidney tissue samples adjacent to renal clear-cell carcinoma were served as normal controls. Laser capture microdissection and real-time RT-PCR were used to assess the expression level of FcRn mRNA in glomeruli of various glomerulonephritides, and immunohistochemistry (IHC) of FcRn by SuperVision method was performed. In addition, rat models of mesangial proliferative nephritis (anti-Thy1.1 nephritis) and passive membranous nephropathy (Heymann nephritis) were established and FcRn was examined in renal tissues by IHC.

RESULTSThe FcRn mRNA level in lupus nephritis was statistically higher than that of normal controls (P < 0.05). FcRn protein expression by IHC was seen in lupus nephritis (6/6), membranous nephropathy (6/9) and IgA nephropathy (7/12), significantly higher than that of normal controls (0/5), P < 0.05. Minimal change disease and focal segmental glomerular sclerosis showed minimal or none expression of FcRn (1/8, 0/4 respectively) and not statistically difference from that of normal controls. Furthermore, FcRn expression in podocytes was detected in rat anti-Thy1.1 (3/5) and Heymann nephritis models (2/7) but was not detected in normal controls.

CONCLUSIONSExpression of FcRn in podocytes was up-regulated in immune-induced human nephritis and rat nephritis models of anti-Thy1.1 nephritis and Heymann nephritis. FcRn may play a role in the development of immune-induced glomerulonephritis.

Animals ; Glomerulonephritis, IGA ; metabolism ; pathology ; Glomerulonephritis, Membranous ; metabolism ; pathology ; Glomerulosclerosis, Focal Segmental ; metabolism ; pathology ; Histocompatibility Antigens Class I ; genetics ; metabolism ; Humans ; Laser Capture Microdissection ; Lupus Nephritis ; metabolism ; pathology ; Male ; Nephritis ; genetics ; immunology ; metabolism ; pathology ; Nephrosis, Lipoid ; metabolism ; pathology ; Podocytes ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Receptors, Fc ; genetics ; metabolism ; Thy-1 Antigens ; immunology ; metabolism ; Up-Regulation

The World Health Organization classifies lupus nephritis as class I to V or VI. However, a few cases of minimal change glomerulopathy have been reported in association with systemic lupus erythematosus (SLE). Mycophenolate mofetil has been shown to be effective for treatment of minimal change disease and lupus nephritis. A 24-year-old woman diagnosed with SLE five years prior to presentation complained of a mild generalized edema. The urinalysis showed microscopic hematuria and proteinuria. The assessed amount of total proteinuria was 1,618 mg/24 hours. A renal biopsy demonstrated diffuse fusion of the foot processes of podocytes on electron microscopy. Mycophenolate mofetil was started in addition to the maintenance medications of prednisolone 10 mg/day and hydroxychloroquine 400 mg/day. After six months of treatment, the microscopic hematuria and proteinuria resolved, and the total urine protein decreased to 100 mg/24 hours.
Antirheumatic Agents/therapeutic use ; Female ; Glucocorticoids/therapeutic use ; Humans ; Hydroxychloroquine/therapeutic use ; Immunosuppressive Agents/*therapeutic use ; Lupus Erythematosus, Systemic/complications/*pathology ; Mycophenolic Acid/*analogs & derivatives/therapeutic use ; Nephrosis, Lipoid/*drug therapy/etiology/pathology ; Prednisone/therapeutic use ; Young Adult

INTRODUCTIONIgA nephropathy is a disease where the pathogenesis is still poorly understood. Deoxyribonucleic acid (DNA) microarray technique allows tens of thousands of gene expressions to be examined at the same time. Commercial availability of microarray genechips has made this powerful tool accessible for wider utilisation in the study of diseases.

MATERIALS AND METHODSSeven patients with IgA nephropathy, 6 with minimal change nephrotic syndrome (MCNS) as patient controls and 7 normal healthy subjects were screened for the differential expression of genes, genome-wide. The Human Genome U133 Plus 2.0 Arrays (Affymetrix, USA) were used to quantitate the differential expression of 38,500 well-characterised human genes.

RESULTSA total of 7761 gene expressions were identified that have an IgAN/Normal gene expression ratio of 0.06-fold to 5.58-fold. About 35% of the altered gene expressions have no gene title or just a hypothetical protein label such as FLJ30679. Most of the remaining 65% are identified proteins where their importance to IgAN is not immediately apparent at this time. Among the 30 most upregulated and 30 most downregulated genes are Urotensin 2 (upregulated 3.09-fold, P <0.05) and Fatty-acid binding protein 6 (downregulated to 0.12-fold, P <0.05). Retinoic acid receptor alpha (vitamin A receptor) was also found downregulated to 0.41-fold (P <0.005). Taqman realtime polymerase chain reaction (PCR) for urotensin 2 and retinoic acid receptor alpha (RARA) were performed on 20 patients with IgA nephropathy and 11 with Minimal Change Disease and the data correlated with various clinical indices.

CONCLUSIONSThe findings suggest that there may be a therapeutic role for retinoic acid receptor alpha (RARA) in IgA nephropathy and a clinical monitoring role for Urotensin 2 in Minimal Change Disease.

Adult ; Aged ; Case-Control Studies ; Female ; Gene Expression ; Gene Expression Regulation ; Genome-Wide Association Study ; Glomerulonephritis, IGA ; genetics ; metabolism ; pathology ; Humans ; Immunoglobulin A ; genetics ; metabolism ; Male ; Middle Aged ; Nephrosis, Lipoid ; genetics ; metabolism ; pathology ; Oligonucleotide Array Sequence Analysis ; Polymerase Chain Reaction ; Receptors, G-Protein-Coupled ; genetics ; metabolism ; Receptors, Retinoic Acid ; genetics ; metabolism ; Tretinoin ; metabolism

OBJECTIVETo investigate the effect of bone mesenchymal stem cell (BMSC) transplantation on repair of glomerular podocytes and on the Nephrin expression in rats with puromycin aminonucleoside (PAN) -induced nephrosis.

METHODSForty-five Sprague-Dawley rats were randomly divided into three groups (n=15 each): a nephrosis model group that received a single intraperitoneal injection of PAN (0.15 mg/g); a BMSC transplantation group that received a single intraperitoneal injection of PAN (0.15 mg/g) followed by BMSC transfusion; a control group that received a single intraperitoneal injection of normal saline. Ten days after injection, the rats were sacrificed. The 24 hrs urinary protein content and serum albumin and cholesterol levels were measured 24 hrs before sacrifice. Changes of glomerular podocytes were observed under an electron microscope. Brdu labeled positive cells in kidneys were measured by immunohistochemical technology. RT-PCR and Western blot were used to assess the expression of mRNA and protein of Nephrin.

RESULTSIn the nephrosis model group, urinary protein and blood cholesterol contents increased, plasma albumin content decreased compared with those in the control group. Extensive fusion of podocyte foot processes was observed in the nephrosis model group. The BMSC transplantation group had decreased urinary protein and blood cholesterol contents and increased plasma albumin content compared with the nephrosis model group. Fusion of podocyte foot processes was also improved. Brdu labeled positive cells were seen in kidneys in the BMSC transplantation group, but not in the nephrosis model and the control groups. Nephrin mRNA and protein expression decreased significantly in the nephrosis model group compared with that in the control group. The BMSC transplantation group had increased Nephrin mRNA and protein expression compared with the nephrosis model group.

CONCLUSIONSBMSCs can repair glomerular podocytes in PAN-induced nephrosis rats, and the changes of Nephrin expression may be involved in the process.

Animals ; Bromodeoxyuridine ; metabolism ; Kidney ; pathology ; Male ; Membrane Proteins ; genetics ; Mesenchymal Stem Cell Transplantation ; Nephrosis, Lipoid ; chemically induced ; pathology ; therapy ; Podocytes ; pathology ; Puromycin Aminonucleoside ; toxicity ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction