A case report of youth-onset lipoprotein glomerulopathy with APOE Chicago mutation.

BACKGROUND: This article reports an extremely rare case of lipoprotein glomerulopathy (LPG) with apolipoprotein E gene (APOE) Chicago mutation in a young Chinese male. Only five cases or families with APOE Chicago mutations have been reported in the literature. CASE PRESENTATION: The young male patient is manifested with nephrotic syndrome, accompanied by hyperlipidemia with a preferable increase in triglycerides and elevated ApoE level. Renal biopsy of the patient showed highly dilated glomerular capillaries filled with vacuolar lipids, segmentally fused podocyte foot processes, vacuolar degeneration of renal tubular epithelial cells and absence of electron-dense material, which indicates the diagnosis of LPG. Whole-exome gene sequencing identified the heterozygous mutation of NM_000041.4:c.494G > C (p.Arg165Pro), which is in the exon 4 of the APOE gene and also known as APOE Chicago mutation, a rare mutation of LPG. Further family pedigree gene analysis clarified that the mutation was inherited from the patient's mother, who does not have high ApoE levels or renal manifestations. This is also consistent with the incomplete penetrance of APOE gene mutations in LPG. Under lipid-lowering treatments, including a low-fat diet and fenofibrate, the patient's urinary protein was partially controlled, and the albumin level was recovered. CONCLUSION: Patients with nephrotic syndrome and elevated ApoE levels should be prompted into renal biopsy to avoid delay of appropriate treatment and unnecessary use of glucocorticoids. This case of LPG was diagnosed by renal biopsy and further verified with genetic sequencing. The timely diagnosis and treatment improved the patient's symptoms. This case is one of only six reported LPG cases or families with APOE Chicago mutation in the world.

Rare renal proximal tubular dysfunctions in primary biliary cholangitis.

INTRODUCTION: Renal involvement of primary biliary cholangitis (PBC) usually presents as distal renal tubular acidosis. Proximal tubular (PT) dysfunctions in PBC were rarely reported with unclear clinicopathological characteristics and renal prognosis. METHODS: We identified 11 cases of PBC with PT dysfunctions (PBC-PT). Their medical document, kidney pathology, and follow-up data were retrospectively reviewed and analyzed. RESULTS: The 11 PBC-PT patients were mainly middle-aged (57.8 ± 5.2 years) females (81.8%). Most of them were asymptomatic PBC (7, 63.6%) with a high prevalence of elevated serum immunoglobulin M (IgM, 81.8%) and G (IgG, 54.5%) levels. In the kidney, they had a mean estimated glomerular filtration rate (eGFR) level of 46.54 ± 23.03 ml/min/1.73m2, and 81.8% of them had eGFR below 60 ml/min/1.73m2. They showed different degrees of PT dysfunctions, including hyperuricosuria, hypouricemia, normoglycemic glycosuria, generalized aminoaciduria, hyperphosphaturia, and hypophosphatemia. Their kidney pathology showed tubulointerstitial nephritis with lymphoplasmacytic infiltrates, brush border defects, and proximal tubulitis. After glucocorticoids treatment, the PT dysfunctions manifesting as hypophosphatemia, hypouricemia, and renal glycosuria all recovered, and the eGFR levels were improved from 43.24 ± 19.60 ml/min/1.73m2 to 55.02 ± 21.14 ml/min/1.73m2 (p = 0.028), accompanied by significant improvements of serum IgM levels (from 5.97 ± 4.55 g/L to 2.09 ± 1.48 g/L, p = 0.019). CONCLUSIONS: The PT dysfunctions were rare in PBC patients, and glucocorticoids treatment could benefit the improvements of eGFR and tubular functions.

Renal Outcomes in Older Adults with Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis: A New Prediction Model.

INTRODUCTION: Older patients with antineutrophil cytoplasmic autoantibody-associated vasculitis (AAV) commonly experience renal impairment and poor prognoses. This study aimed to establish a risk-scoring system for predicting composite renal outcomes in older patients with AAV. METHODS: This retrospective observational study included all patients with AAV hospitalized in a single-center tertiary hospital in China between January 2013 and April 2022. Patients aged ≥65 years were defined as older adults and short-term composite renal outcomes included a ≥25% reduction in estimated glomerular filtration rate (eGFR) (for AKI), renal replacement therapy, provision of renal replacement therapy (long-term dialysis, kidney transplant, or sustained eGFR <15 mL/min/1.73 m), or all-cause mortality. Patients were randomly divided into development and validation cohorts (2:1). Logistic regression analysis was performed in the development cohort to analyze risk factors. The scoring system was established accordingly and further validated in the validation cohort. RESULTS: 1,203 patients were enrolled in the study, among whom the older adult group accounted for 36% with a mean age of 71. The older adult group had a worse prognosis, a higher mortality rate, a higher rate of end-stage renal disease, and worsening renal function. Logistic regression showed that age >75 years, chronic heart disease, and elevated serum creatinine and D-dimer values were risk factors for poor prognosis in patients with AAV. The development and validation cohorts in patients with AAV produced area under the curve values of 0.82 (0.78-0.86) and 0.83 (0.77-0.89), respectively. CONCLUSION: We established a risk-scoring system based on baseline clinical characteristics to predict composite renal outcomes in patients with AAV. Our results suggest that more attention should be paid to older patients with severe renal impairment and active inflammation.

[Therapeutic effect of mycophenolate mofetil or cyclophosphamide in children with Henoch-Schönlein purpura nephritis of different age groups]. / ä¸åŒå¹´é¾„æ®µè¿‡æ•æ€§ç´«ç™œæ€§è‚¾ç‚Žæ‚£å„¿æŽ¥å—éœ‰é šé ¸é ¯æˆ–çŽ¯ç£·é °èƒºæ²»ç–—çš„ç–—æ•ˆå·®å¼‚åˆ†æž.

OBJECTIVES: To investigate the difference in the therapeutic effect of mycophenolate mofetil (MMF) or cyclophosphamide (CTX) in children with Henoch-Schönlein purpura nephritis (HSPN) of different age groups. METHODS: A retrospective analysis was conducted on the clinical data of 135 children with HSPN who were treated with MMF or CTX in the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics, from October 2018 to October 2020. According to the immunosuppressant used, they were divided into two groups: MMF group and CTX group, and according to the age, each group was further divided into two subgroups: ≤12 years and >12 years, producing four groups, i.e, the ≤12 years MMF subgroup (n=30), the >12 years MMF subgroup (n=15), the ≤12 years CTX subgroup (n=71), and the >12 years CTX subgroup (n=19). All children were followed up for at least 12 months, and the above groups were compared in terms of clinical outcomes and the incidence rate of adverse reactions. RESULTS: There was no significant difference in the complete response rate between the MMF group and the CTX group after 3, 6, and 12 months of treatment (P>0.05). There were no significant difference in the complete response rate and the incidence rate of adverse reactions between the >12 years MMF subgroup and the ≤12 years MMF subgroup at 3, 6, and 12 months of treatment (P>0.05). The >12 years CTX subgroup had a significantly lower complete response rate than the ≤12 years CTX subgroup at 6 and 12 months of treatment (P<0.05). The >12 years CTX subgroup had a significantly higher incidence rate of adverse reactions than the >12 years MMF subgroup (P<0.05). CONCLUSIONS: The efficacy and adverse reactions of MMF are not associated with age, but the efficacy of CTX is affected by age, with a higher incidence rate of adverse reactions. CTX should be selected with caution for children with HSPN aged >12 years.

The spectrum of kidney biopsy findings in Chinese HIV-infected patients.

OBJECTIVES: HIV-associated kidney disease is common but data on the pathology spectrum of kidney biopsy in China is lacking. This study aimed to illustrate the clinical presentation, laboratory findings and pathological spectrum of different subtypes of HIV-associated kidney disease in China. METHODS: Eighteen HIV patients with renal biopsy indications at the Peking Union Medical College Hospital from January 2002 to October 2021 were retrospectively enrolled. All had CD4 counts and HIV viral load measurements. Renal biopsies were examined with light microscopy, immunofluorescence, and electron microscopy. Shapiro-Wilk test was used to test whether the data was normally distributed. The data is presented as medians (interquartile range), number (%), or means (±SD) according to their distribution. RESULTS: Seventeen patients had glomerular disease, and one patient had interstitial nephritis. Membranous nephropathy was present in eight patients (47.1%), and IgA nephropathy in four patients (23.5%). The difference in urine protein and serum albumin before and after treatment was statistically significant and no deaths or dialysis were observed to the end of follow-up. CONCLUSION: This study found that classic HIV-associated nephropathy (HIVAN) was uncommon in Chinese HIV patients. HIV immune complex kidney (HIVICK) disease, such as membranous or IgA nephropathy, was more common, and associated with better prognosis. Antiretroviral therapy, ACE inhibitors, and angiotensin II receptor blockers were effective in decreasing proteinuria and preserving renal function. The use of corticosteroids and immunosuppressive agents seems safe. However, the nephrotoxic effect of antiretroviral agents and other medications should be carefully monitored.

Anti-neutrophil cytoplasmic antibody associated vasculitis in patients with rheumatoid arthritis.

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) may coexist with rheumatoid arthritis (RA). However, it is unclear whether the manifestations of AAV with and without coexisting RA are similar. This observational study aimed to investigate the clinicopathological manifestations of AAV with coexisting RA and to explore potential predictors for identifying AAV superimposed on RA. METHODS: Patients with both AAV and RA were identified by searching our hospital database and the literature. Data including age, sex, clinical manifestation, laboratory tests, renal pathology, and therapeutic regimens were retrieved. To assess the difference in clinical features and renal pathology between AAV patients with and without RA, we conducted 1:4 matched case-control studies. RESULTS: A total of 47 patients were identified, 15 from our hospital and 32 from the literature, and 33 (70.2%) were women. AAV was diagnosed later than RA in 83.0% of the patients and manifested as microscopic polyangiitis (MPA) in 78.7% of the patients. The kidney was the most frequently involved extra-articular organ (74.5%), followed by the lung (51.1%), and skin (8.5%). Patients with both AAV and RA were more likely to be asymptomatic (26.7% vs 3.3%, p = 0.013) than those with isolated AAV. However, they did not differ in other clinicopathological features. In RA patients, those with ANCA associated glomerulonephritis, were more likely to have decreased renal function at renal biopsy as opposed to those with primary glomerulonephritis. CONCLUSIONS: AAV can coexist with RA. In this coexistence, AAV usually develops after RA, is more likely to be asymptomatic, and manifests predominately as MPA with renal involvement. Thus, we should remain vigilant to superimposed AAV on RA.

[Nephrotic Syndrome Caused by AA Amyloidosis Secondary to Unicentric Castleman's Disease:Report of One Case].

AA amyloidosis is a rare systemic complication caused commonly by chronic inflammatory arthritis,periodic fever disease,vasculitis,tumors,etc.Castleman's disease is an uncommon cause of AA amyloidosis.Here,we reported a case of unicentric Castleman's disease-induced AA amyloidosis with nephrotic syndrome as the main manifestation.The laboratory examination showed elevated levels of inflammatory indicators.We summarized the clinical manifestations,diagnosis,and therapy of this case,aiming to facilitate the management of patients with unknown reasons of renal amyloidosis.

Clinicopathological Features and Outcomes of Acute Kidney Injury in Critically Ill COVID-19 with Prolonged Disease Course: A Retrospective Cohort.

BACKGROUND: The incidence, severity, and outcomes of AKI in COVID-19 varied in different reports. In patients critically ill with COVID-19, the clinicopathologic characteristics of AKI have not been described in detail. METHODS: This is a retrospective cohort study of 81 patients critically ill with COVID-19 in an intensive care unit. The incidence, etiologies, and outcomes of AKI were analyzed. Pathologic studies were performed in kidney tissues from ten deceased patients with AKI. RESULTS: A total of 41 (50.6%) patients experienced AKI in this study. The median time from illness to AKI was 21.0 (IQR, 9.5-26.0) days. The proportion of Kidney Disease Improving Global Outcomes (KDIGO) stage 1, stage 2, and stage 3 AKI were 26.8%, 31.7%, and 41.5%, respectively. The leading causes of AKI included septic shock (25 of 41, 61.0%), volume insufficiency (eight of 41, 19.5%), and adverse drug effects (five of 41, 12.2%). The risk factors for AKI included age (per 10 years) (HR, 1.83; 95% CI, 1.24 to 2.69; P=0.002) and serum IL-6 level (HR, 1.83; 95% CI, 1.23 to 2.73; P=0.003). KDIGO stage 3 AKI predicted death. Other potential risk factors for death included male sex, elevated D-dimer, serum IL-6 level, and higher Sequential Organ Failure Assessment score. The predominant pathologic finding was acute tubular injury. Nucleic acid tests and immunohistochemistry failed to detect the virus in kidney tissues. CONCLUSIONS: AKI was a common and multifactorial complication in patients critically ill with COVID-19 at the late stage of the disease course. The predominant pathologic finding was acute tubular injury. Older age and higher serum IL-6 level were risk factors of AKI, and KDIGO stage 3 AKI independently predicted death.

Clinicopathological study of mixed cryoglobulinemic glomerulonephritis secondary to hepatitis B virus infection.

BACKGROUND: Cryoglobulinemic glomerulonephritis (CryoGn) caused by hepatitis B virus (HBV) infection was rarely reported. Our study aimed to investigate the clinical features, renal pathology findings, and prognosis in patients with HBV related CryoGn. METHODS: This was a retrospective study including seven Chinese patients with HBV related CryoGn in a tertiary referral hospital from April 2016 to March 2019. The clinical and pathological data were collected and analyzed. RESULTS: Age at renal biopsy was 47 ± 12 years, with female/male ratio 3/4. Urine protein was 5.6 (3.0, 6.6) g/d and five cases presented with nephrotic syndrome. The baseline eGFR was 23.5 (20.2, 46.3) ml/min per 1.73m2. The extrarenal manifestations included purpura (n = 6), arthralgia (n = 1), peripheral neuropathy (n = 1), and cardiomyopathy (n = 1). Six cases had type II cryoglobulinemia with IgMκ, the other one had type III. The median cryocrit was 4.0 (1.0, 15.0) %. Renal pathologic findings on light microscopy: endocapillary proliferative glomerulonephritis (Gn) (n = 3), membranoproliferative Gn (n = 3), and mesangial proliferative Gn (n = 1). On immunofluorescence microscopy, the predominant type of immunoglobulin deposits was IgM (n = 5). HBsAg and HBcAg deposits were found in one case. Ultrastructural studies showed granular subendothelial and mesangial electron-dense deposits in all patients and microtubules in one case. All patients received antiviral medications. They were given corticosteroid alone (n = 2) or combined with cyclophosphamide (n = 4) or mycophenolate mofetil (n = 1). Two patients received plasmapheresis. The median follow-up time was 18 (6, 37) months. Four patients got remission, two patients died of pneumonia, and one progressed to end-stage renal disease (ESRD). At endpoint of follow-up, 24hUP was 2.1 (0.8-5.2) g/d, and eGFR was 55.3 (20.7, 111.8) ml/min per 1.73m2. The median cryocrit decreased to 1.0 (0, 5.75) %. CONCLUSIONS: The etiology of mixed CryoGn should be screened for HBV infection. Endocapillary proliferative Gn and membranoproliferative Gn were the common pathologic patterns. Diagnosis and treatment in early stage benefit patients' renal outcomes. Immunosuppressive therapy should be considered for severe renal disease, based on efficient antiviral therapy.

Clinical significance of C4d deposition in renal tissues from patients with primary Sjögren's syndrome-a preliminary study.

BACKGROUND: To evaluate renal expression of C4d, a complement component in the classical/mannose binding lectin (MBL) pathway, in patients with primary Sjögren's syndrome (pSS)-associated renal impairments. METHODS: We retrospectively reviewed the clinical and pathological data from 39 patients with pSS presenting with renal impairments. C4d was examined in paraffin-embedded biopsy tissues using immunohistochemistry. Glomerular C4d positive was defined when > 75% glomeruli were globally stained. Tubulointerstitial C4d (TI-C4d) were scored semi-quantitatively as 0 (absent), 1 (spotty or weak), 2 (patchy) and 3 (diffuse). A TI-C4d score ≥ 2 was considered TI-C4d positive and included in the TI-C4d+ group and vice versa. Peritubular capillary (PTC) C4d was scored as 0 (absent), 1 (0~10%, minimal), 2 (10%~ 50%, focal), and 3 (> 50%, diffuse). RESULTS: Glomerular C4d deposition was observed in all 8 patients with pSS-related membranous nephropathy (MN) without obvious C1q deposition. Two of 5 patients with mesangial proliferative glomerulonephritis and 1 of 2 patients with IgA nephropathy had mild mesangial C4d deposition. Sixteen patients (6 glomerular dominant and 10 tubulointerstitial dominant) presented TI-C4d score ≥ 2. Patients in the TI-C4d+ group exhibited a higher serum creatinine level at the time of renal biopsy (TI-C4d+ 132.5 [89.7, 165.5] vs. TI-C4d- 83.0 [70.7, 102.0] µmol/L, P = 0.008). PTC C4d was observed in 12 patients, with each of minimal, focal and diffuse staining being noted in 4 patients. CONCLUSIONS: The MBL pathway of complement activation was potentially involved in pSS-related MN. Tubulointerstitial C4d might be a pathological marker of severe renal injury in patients with pSS-related renal impairments.

Serum levels of tumor necrosis factor alpha in patients with IgA nephropathy are closely associated with disease severity.

BACKGROUND: Tumor necrosis factor alpha (TNF-α) is considered to play an important role in the pathogenesis in IgA nephropathy (IgAN). The correlations between serum TNF-α and disease severity in patients with IgAN remain controversial. METHODS: Concentrations of serum TNF-α of 147 patients with IgAN and 126 healthy subjects were measured by chemiluminescence immunoassay. Correlations with clinicopathological features of patients with IgAN were evaluated. RESULTS: Serum levels of TNF-α [9.20 (7.70-10.60) pg/mL vs. 6.04 (5.11-7.23) pg/mL, P < 0.0001] were higher in patients with IgAN than that in healthy subjects. Receiver operating characteristic curve analysis revealed that TNF-α had better discrimination between patients with IgAN and healthy controls than estimated glomerular filtration rate [TNF-α: (AUC, 0.87; 95% CI, 0.83-0.91; P < 0.0001) vs. estimated glomerular filtration rate: (AUC, 0.76; 95% CI, 0.71-0.82; P < 0.0001), P = 0.007]. Multivariate linear regression analyses showed that serum levels of TNF-α were positively correlated with 24-h urine protein excretion (r = 0.33, P = 0.04), urinary protein to serum creatinine ratio (r = 0.33, P = 0.03), serum creatinine (r = 0.46, P < 0.0001) and Cystatin C (r = 0.59, P < 0.0001) in IgAN and negatively correlated with estimated glomerular filtration rate (r = - 0.49, P < 0.0001) after adjustment for sex, systolic blood pressure and diastolic blood pressure. Patients with higher mesangial hypercellularity or tubular atrophy/interstitial fibrosis score according to Oxford classification showed higher serum levels of TNF-α. CONCLUSIONS: Our data showed that serum levels of TNF-α detected by chemiluminescence immunoassay was a potential biomarker for evaluating the disease severity in IgAN.

Analysis of predictive factors for immunosuppressive response in anti-phospholipase A2 receptor antibody positive membranous nephropathy.

BACKGROUND: Serum anti-phospholipase A2 receptor (PLA2R) antibody was correlated with disease activity of membranous nephropathy(MN). The predictive value of antibody titer changes on immunosuppressive response remains unknown. We investigated predictive value of dynamic change of anti-PLA2R antibody and 24-h urine protein (24hUP) for clinical response of MN. METHODS: This was a retrospective cohort study including 47 Chinese MN patients with positive anti-PLA2R antibody in a tertiary referral hospital between January 2012 and March 2014. Patients received cyclophosphamide (CTX, n = 23), or cyclosporine (CYA, n = 24) regimen, respectively. We monitored serum anti-PLA2R titer and 24hUP at one, three and six-month follow-up. RESULTS: At baseline, total patients were 42 ± 14 years old with 29/18 male/female ratio. The median 24hUP was 5.80(3.56,9.41) g/d. The median baseline anti-PLA2R antibody titer was 66.4(31.9, 188.0) RU/mL. Baseline 24hUP and eGFR between subgroups were not significantly different. The differences of relative reduction between antibody titer and 24hUP at one month were statistically significant (CTX group 94.2% vs. 46.8%, P < 0.001; CYA group 54.6% vs. 4.6%, P = 0.04). Only in CTX group, the relative reduction of 24hUP at one month was correlated with composite remission at six-month(P = 0.03). Area under the curve of 24hUP relative reduction in CTX group at one-month for predicting composite remission at six months was 0.85(95%CI 0.65~1.05, P = 0.04). The cutoff value of one-month's 24hUP relative reduction for predicting six-month's composite remission in CTX group was 15.3%, with high sensitivity (83.3%) and specificity (100%). CONCLUSIONS: Compared with relative reduction of antibody titer, relative reduction of 24hUP at one-month follow-up in CTX group had a better predictive value for six-month's composite remission.

The renal manifestations of type 4 familial partial lipodystrophy: a case report and review of literature.

BACKGROUND: Lipodystrophy syndromes are rare disorders of variable body fat loss associated with potentially serious metabolic complications. Familial partial lipodystrophy (FPLD) is mostly inherited as an autosomal dominant disorder. Renal involvement has only been reported in a limited number of cases of FPLD. Herein, we present a rare case of proteinuria associated with type 4 FPLD, which is characterized by a heterozygous mutation in PLIN1 and has not been reported with renal involvement until now. CASE PRESENTATION: A 15-year-old girl presented with insulin resistance, hypertriglyceridaemia, hepatic steatosis and proteinuria. Her glucose and glycated haemoglobin levels were within normal laboratory reference ranges. A novel heterozygous frameshift mutation in PLIN1 was identified in the patient and her mother. The kidney biopsy showed glomerular enlargement and focal segmental glomerulosclerosis under light microscopy; the electron microscopy results fit with segmental thickening of the glomerular basement membrane. Treatment with an angiotensin-converting enzyme inhibitor (ACEI) decreased 24-h protein excretion. CONCLUSIONS: We report the first case of proteinuria and renal biopsy in a patient with FPLD4. Gene analysis demonstrated a novel heterozygous frameshift mutation in PLIN1 in this patient and her mother. Treatment with ACEI proved to be beneficial.

Fibronectin Glomerulopathy Caused by the Y973C Mutation in Fibronectin: A Case Report and Literature Review.

Fibronectin glomerulopathy is a rare autosomal dominant inherited glomerular disease associated with massive deposition of fibronectin. We recently diagnosed fibronectin glomerulopathy in a 29-year-old woman presenting nephrotic syndrome. Genetic analysis of fibronectin 1 gene showed heterozygosity for the Y973C mutation. However, this mutation was not found in her parents. She had stable renal function but persistent nephrotic proteinuria after one-year follow-up.

The Neglected Significance of Glomerular Density as a 5-year Progression Indicator for IgA Nephropathy△.

Objective To investigate whether glomerular density (GD) could be an independent prognostic factor for patients of IgA nephropathy with estimated glomerular filtration rate (eGFR) of 30 to 60 ml/min per 1.73 m2, or for patients with time-average proteinuria < 0.5 g/d. Methods A total of 173 patients with biopsy-confirmed IgA nephropathy diagnosed from January 2000 to December 2010 were included. All of these patients were followed up for more than 5 years. The endpoint was a > 30% of decline in eGFR from baseline after 5-year follow-up. The optimal cut-off value of GD was calculated by ROC curve. Kaplan-Meier method and Cox regression analysis was used for survival analysis. Results A 30% of decline in eGFR occurred in 14.5% of all patients. The optimal diagnostic cut-off value of GD was 1.99/mm2 (AUC = 0.90, sensitivity = 84.0%, specificity = 81.8%) determined by ROC curve. The low GD group (GD < 1.99 per mm2) experienced a significant increase in renal endpoint for patients with eGFR of 30 to 60 ml/min per 1.73 m2 (six patients in lower GD group, while one patient in the other group). For patients with time-average proteinuria < 0.5 g/d, the lower GD group showed a higher eGFR decline from baseline (4.5±16.7 ml/min per 1.73 m2 vs. -8.1±21.4 ml/min per 1.73 m2, P = 0.038); two patients in this group reached the endpoint, while no patients in the higher GD group did. Conclusion GD could be an independent prognostic factor for patients of IgA nephropathy with eGFR at 30 to 60 ml/min per 1.73 m2 of body surface, particularly for those with time-averaged amount of urine protein less than 0.5 g per day.

Clinicopathological Features of Idiopathic Membranous Nephropathy in 33 Adolescents.

Objective To investigate the clinicopathological features and prognosis of idiopathic membranous nephropathy(IMN)in adolescents. Methods This was a retrospective study on IMN patients hospitalized between June 2012 and December 2014,and a total of 33 IMN patients aged between 13 and 24 years old were enrolled in the study.Meanwhile,33 IMN patients aged more than 24 years old were selected randomly as control group during the same period.Diagnosis was confirmed by renal biopsy,and the secondary causes of membranous nephropathy were ruled out.Data collected from medical record and biopsy were analyzed. Results In the adolescent IMN group,the mean age at renal biopsy was(20±3)years old,and the male/female ratio was 22/11.Twenty-three cases presented as nephrotic syndrome.Systolic and diastolic pressures were(127±13)mmHg and(77±9)mmHg,respectively.The median 24-hour urine protein was 5.14(3.39,9.31)g/d,and the median serum creatinine was 62(52,73)µmol/L.The positive rate of serum anti-phospholipase A2 receptor in adolescent group was 54%.Compared with control group,the adolescent patients had lower incidence of hypertension and higher baseline estimated glomerular filtration rate level [15.2% vs.39.3%,χ2=4.889,P=0.03;125 ml/(min·1.73m2)vs.100 ml/(min·1.73m2),U=137.5,P<0.001].According to IMN staging criteria in electron microscopy,adolescent patients were classified as one case in stage I,21 in stage Ⅱ,and 11 in stage Ⅲ or higher.The positive rates of IgG1,IgG2,IgG3 and IgG4 subclass staining in glomeruli were 46.9%,3.1%,56.3%,and 87.5%,respectively.Compared with control group,the adolescent patients had lower incidence of renal interstitial fibrosis and arteriolar lesions(6.1% vs.66.7%,χ2=26.19,P<0.001;15.2% vs.66.7%,χ2=18.11,P<0.001).Three patients lost to follow-up while others started steroid combined with cyclosporine A(n=20),cyclophosphamide(n=7),or mycophenolate(n=1)or solely(n=2).After a median follow-up of 18(12,24)months,the median proteinuria decreased to 0.20(0.10,0.42)g/d,whereas serum creatinine level remained stable [69(56.8,81.3)µmol/L].Seventeen patients(56.7%)achieved complete remission(CR),and the remaining 13 patients(43.4%)achieved partial remission(PR).The median time of CR and PR were three and six months,respectively.Only one patient relapsed during the follow-up.Also,21 cases received maintenance therapy including cyclosporine A(n=18),azathioprine(n=2)and mycophenolate(n=1).Conclusions The immunofluorescence IgG subclass in glomeruli and distribution of serum anti-phospholipase A2 receptor in adolescent IMN patients are similar to those in older IMN patients.IMN patients in adolescents responded well to immunosuppressive therapy.Cyclosporine A in low dose as maintenance therapy is effective after achieving remission,and will not increase risk of nephrotoxicity.

Endoplasmic Reticulum Stress Predicts Clinical Response to Cyclosporine Treatment in Primary Membranous Nephropathy.

BACKGROUND: Little is known about the endoplasmic reticulum stress (ERS) marker glucose regulated protein 78 (GRP78) and calcineurin in the kidney in primary membranous nephropathy (PMN) and if they could predict post-cyclosporine treatment outcome. METHODS: This is a retrospective study using a dataset of biopsy-confirmed PMN from Peking Union Medical College Hospital from 1996 to 2014. Seventy-six adult patients treated with cyclosporine as primary immunosuppression for at least 6 months were studied. Immunohistochemistry was used to detect GRP78 and calcineurin in the kidney. Serum calcineurin was assayed by ELISA. Patients were grouped into no-remission (NR, n = 17), partial remission (PR, n = 39), or complete remission (CR, n = 20) at the end of 6 months of treatment. RESULTS: There was no difference of initial dose of cyclosporine among NR, PR, and CR groups. Kidney calcineurin expression in PMN was significantly increased compared to that in controls (p < 0.0083). The glomerular GRP78 in NR PMN was higher than that in control, CR and PR patients (p < 0.0083). Kidney calcineurin expression and GRP78 expression was positively correlated. However, there were no differences in either serum calcineurin levels or kidney calcineurin expressions among NR, PR or CR groups. There was a negative correlation between serum calcineurin activity and whole kidney calcineurin expression (p = 0.034) or glomerular calcineurin expression (p = 0.007). Neither kidney calcineurin nor GRP78 expression was correlated with proteinuria. CONCLUSIONS: ERS marker GRP78 in the glomeruli but not serum or kidney calcineurin expression could be a useful marker in PMN to negatively predict the response to cyclosporine treatment at the sixth month.

[The relationship between anti-phospholipase A2 receptor antibody and idiopathic membranous nephropathy].

OBJECTIVE: To explore the value of anti-phospholipase A2 receptor (PLA2R) antibody in the diagnosis and disease activity monitoring of idiopathic membranous nephropathy (IMN). METHODS: A total of 233 patients with IMN proven by kidney biopsy at Peking Union Medical College Hospital from January 2012 to March 2014 were enrolled in this study. Another 46 patients with non-IMN kidney diseases at the same period were selected as control group. Serum titer of anti-PLA2R antibody was measured by quantitative enzyme-linked immuno sorbent assay (ELISA) at the time of renal biopsy. Clinical data were reviewed and retrospectively analyzed. The diagnostic accuracy of anti-PLA2R antibody in IMN was estimated by ROC curve. RESULTS: The total sensitivity of anti-PLA2R antibody was 60.0% in IMN. However, the sensitivity increased to 71.3% in patients who did not receive immuno-suppression therapies. The specificity of anti-PLA2R antibody was 100.0%, of which was not detected in any of the 25 control patients with lupus nephritis. The area under ROC curve of anti-PLA2R antibody for IMN diagnosis was 0.800. The prevalence of positive anti-PLA2R antibody in nephrotic range proteinuria group and non-nephrotic range proteinuria group were 68.3% and 41.7% (P < 0.05), respectively. The positive rates in patients with serum albumin level less than 30 g/L and more than 30 g/L were 67.3% and 44.6% (P < 0.05), respectively. Hypoalbuminemia became worse (P < 0.05) and the proportion of nephrotic arrange proteinuria rose significantly (P < 0.05) according to the elevation of antibody level. CONCLUSIONS: Anti-PLA2R antibody has high sensitivity and notable specificity for the diagnosis of IMN, which reveals good diagnostic accuracy. The antibody positive rate is affected by immunosuppression therapy, disease activity and other clinical status. Moreover, the antibody could reflect the disease activity.

Clinical features of 30 patients with cryoglobulinemia.

OBJECTIVE: To summarize the clinical features of cryoglobulinemia. METHOD: We retrospectively analyzed the clinical data of 30 patients admitted to Peking Union Medical College Hospital from January 2003 to March 2013 due to cryoglobulinemia. RESULTS: The average age was(53.8±11.9)years in these 30 patients(12 men and 18 women),among whom 22 patient(73.3%)developed infectious diseases including hepatitis B(n=11)and hepatitis C(n=11);in addition,3 hepatitis B patients and 1 hepatitis C patient also had malignancies. Four patients(13.3%)were accompanied with malignant lymphocytic proliferation diseases,and three(10.0%)with connective tissue diseases. The cause of disease was unclear in 5 patients(16.7%). The clinical manifestations varied due to the primary diseases;notably,20 patients(66.7%)had an onset of purpura rash,22(73.3%)and 19(63.3%)were accompanied with hypertension and chronic renal insufficiency,respectively. The severity of renal involvement was relevant with the increase of C reactive protein,erythrocytes,sedimentation rate,and IgM and the decrease of complements. Treatment should be directed at the primary diseases. Glucocorticoid and immunosuppressants were good choices for relieving renal involvement. Elderly, type 1 cryoglobulinemia,and poor renal function were associated with the poor prognosis. CONCLUSIONS: Cryoglobulinemia is mainly seen in middle and elderly patients. It can often affect multiple systems,in particular the kidney. Inflammatory markers,IgM,and complements is related with the disease severity. Age,primary disease,and renal function are related with prognosis.

[Expression of calcineurin in podocytes in response to endoplasmic reticulum stress in diabetic nephropathy].

OBJECTIVE: To investigate the regulation of calcineurin (CaN) by endoplasmic reticulum stress (ERS) in podocytes in vitro and in vivo at the stage microalbuminuria in diabetic nehropathy (DN). METHODS: The urinary albumin excretions of C57BLKS/J (Lepr) db/db and db/m mice at the ages of 6, 9, and 12 weeks were measured. The expressions of CaN and synaptopodin of these mice were observed. In immortalized mouse podocytes, the expression of podocyte CaN incubated with different concentrations of paltimate was quantitatively determined by real-time PCR. The changes of CaN incubated with paltimate with or without ursodeoxy-cholic acid (UDCA) were analyzed by confocal microscopy and Western blotting. RESULTS: As urine protein increased, the expression of CaN was enhanced and the expression of synaptopodin was reduced in early stage DN db/db mice potocytes. In immortalized mouse podocytes, as the concentrations of palmitate increased, CaN mRNA increased. By confocal microscopy, the fluorescence intensity of CaN increased in palmitate treatment group. After co-incubation with palmitate and UDCA, the fluorescence intensity decreased. The similar results were shown by Western blotting. CONCLUSION: At the stage of microalbuminuria in DN, ERS in podocytes up-regulates the expression of CaN.