Fu-de Zhou

The changing spectrum of primary glomerular diseases within 15 years: A survey of 3331 patients in a single Chinese centre

BACKGROUND Primary glomerular disease (PGD) is the leading cause of end-stage renal disease (ESRD) in China. With the development of socioeconomic status of Chinese people in the last two decades, PGD in ESRD is intent to decrease. However, whether this affects the spectrum of PGD is not clear. The aim of the current study is to investigate the changing spectrum of PGD in China. METHODS The records of 5398 consecutive native renal biopsies performed in adults (>or=14 years of age) in our centre between 1993 and 2007 were retrospectively analysed. The criteria for renal biopsy and pathologic diagnosis were kept unchanged. The patients were grouped according to a 5-year interval, 1993-97 (period 1), 1998-2002 (period 2) and 2003-07 (period 3). Then they were divided into four groups according to age for stratified analysis: 14-24 years, 25-44 years, 45-59 years and the elderly (>or=60 years). RESULTS Three thousand, three hundred and thirty-one patients were diagnosed with PGD. PGD remained the most common renal disease, accounting for 65.9%, 57.7% and 63.2% in period 1, 2 and 3, respectively, without any significant difference. The proportion of elder patients increased significantly from 0% in 1993 to 9.1% in 2007 (P < 0.001). Within 1993-97, the leading PGD was IgA nephropathy (50.7%), followed by non-IgA MsPGN (19.9%), membranous nephropathy (MN) (13.3%) and minimal change disease (MCD) (6.3%), while within 2003-07, the most common PGD was still IgAN (58.2%), but followed by MN (14.3%), MCD (13.4%) and non-IgA MsPGN (7.0%). The age-adjusted frequency of IgAN and MCD increased significantly from period 1 to period 3 (P < 0.01 and P < 0.001, respectively), while that of non-IgA MsPGN, EnPGN and MPGN decreased significantly (P < 0.001, P < 0.01 and P < 0.05, respectively). There was no significant change in the age-adjusted frequency of FSGS, MN and CreGN during the study period. However, when patients were stratified by age, a sixfold increase in frequency of FSGS was identified in the 14- to 24-year group (P < 0.01). CONCLUSIONS The spectrum of primary glomerulonephritis has changed within the last 15 years. The relative frequency of non-IgA MsPGN, EnPGN and MPGN decreased significantly, while that of MCD and IgA nephropathy increased significantly. The relative frequency of FSGS increased significantly in younger patients.

Interaction between PLA2R1 and HLA-DQA1 Variants Associates with Anti-PLA2R Antibodies and Membranous Nephropathy

Risk alleles at genome loci containing phospholipase A2 receptor 1 (PLA2R1) and HLA-DQA1 closely associate with idiopathic membranous nephropathy (IMN) in the European population, but it is unknown whether a similar association exists in the Chinese population and whether high-risk alleles promote the development of anti-PLA2R antibodies. Here, we genotyped 2132 Chinese individuals, including 1112 patients with IMN and 1020 healthy controls, for three single nucleotide polymorphisms (SNPs) within PLA2R1 and three SNPs within HLA genes. We also selected 71 patients, with varying genotypes, to assess for circulating anti-PLA2R antibody and for PLA2R expression in glomeruli. Three SNPs within PLA2R1 and one SNP within HLA-DQA1 strongly associated with IMN, and we noted gene-gene interactions involving these SNPs. Furthermore, these risk alleles strongly associated with the presence of anti-PLA2R antibodies and glomerular PLA2R expression. Among individuals who carried risk alleles for both genes, 73% had anti-PLA2R antibodies and 75% expressed PLA2R in glomeruli. In contrast, among individuals who carried protective genotypes of both genes, none had anti-PLA2R antibodies and glomerular expression of PLA2R was weak or absent. In conclusion, the interaction between PLA2R1 and HLA-DQA1 risk alleles associates with the development of IMN in the Chinese population. Individuals carrying risk alleles are predisposed to the generation of circulating anti-PLA2R autoantibodies, which may contribute to the development of IMN.

The renal histopathological spectrum of patients with nephrotic syndrome: an analysis of 1523 patients in a single Chinese centre

BACKGROUND Nephrotic syndrome is caused by a variety of glomerulopathy. The current study investigated the renal histopathological spectrum of patients with nephrotic syndrome who received a renal biopsy in our department within the last 15 years. METHODS One thousand five hundred and twenty-three consecutive patients (≥14 years old at renal biopsy) with nephrotic syndrome were recruited. Patients were divided into four groups according to age at the time of renal biopsy. The renal histopathological spectrum was also compared between nephrotic-range proteinuria patients with and without hypoalbuminaemia. RESULTS Among the 1523 patients, the most common cause of nephrotic syndrome was idiopathic membranous nephropathy (IMN) (20.7%), followed by minimal change disease (MCD) (20.4%). Among the patients aged 14-24, 25-44, 45-59 and ≥60 years, the most common cause of nephrotic syndrome was MCD (33.0%), lupus nephritis (LN) (23.0%), IMN (37.9%) and IMN (42.3%), respectively. Among the female patients aged 14-24 and 25-44 years, LN was the leading cause of nephrotic syndrome (35.8 and 36.2%, respectively). The proportion of patients with renal amyloidosis increased in parallel with patient age. The comparison between nephrotic patients with and without hypoalbuminaemia suggests that patients with MCD, LN or renal amyloidosis were more likely to develop hypoalbuminaemia. CONCLUSIONS The renal histopathological spectrum of nephrotic syndrome differs between ages. MCD, LN and IMN were the main cause of nephrotic syndrome among younger patients, and IMN was the main cause of nephrotic syndrome among older patients. The proportion of patients with renal amyloidosis increased in parallel with patient age.

Increasing frequency of idiopathic membranous nephropathy in primary glomerular disease: A 10-year renal biopsy study from a single Chinese nephrology centre

To investigate the changing of idiopathic membranous nephropathy (iMN) in China.

Normoalbuminaemia is associated with IgA nephropathy in primary glomerulopathy with nephrotic-range proteinuria in Chinese patients

BACKGROUND Massive proteinuria is often associated with hypoalbuminaemia in glomerulopathy. However, patients may have normal levels of serum albumin despite heavy proteinuria in many circumstances. This study analysed factors affecting serum levels of albumin in primary glomerulopathy patients with nephrotic-range proteinuria. METHODS The renal histopathological data of 780 consecutive adult patients (age ≥ 18 years old) with primary glomerulopathy and nephrotic-range proteinuria, who received native renal biopsies in Peking University First Hospital from 1998 to 2007, were retrospectively analysed. RESULTS Compared with patients with hypoalbuminaemia (serum albumin < 30 g/L), patients without hypoalbuminaemia were significantly younger (P < 0.001) and had significantly lower levels of proteinuria (P < 0.001). Patients without hypoalbuminaemia had a significantly higher proportion of IgA nephropathy (66.0% vs. 17.2%, P < 0.001). The independent predictors of hypoalbuminaemia in nephrotic-range proteinuria patients included age, gender, interval between onset of the disease and renal biopsy, proteinuria level, and pathological type of glomerulopathy. A serum level of albumin ≥ 35 g/L could predict IgA nephropathy with a specificity of 95.8%, and specificity increased with age. CONCLUSIONS Among patients with primary glomerulopathy and nephrotic-range proteinuria, normoalbuminaemia is associated with IgA nephropathy.

Acute Kidney Injury and Bilateral Symmetrical Enlargement of the Kidneys as First Presentation of B-Cell Lymphoblastic Lymphoma

Lymphoblastic lymphoma is an uncommon subtype of lymphoid neoplasm in adults. Acute kidney injury at initial presentation due to lymphoblastic lymphoma infiltration of the kidneys has rarely been described. We report a 19-year-old woman who presented with acute kidney injury due to massive lymphomatous infiltration of the kidneys. The diagnosis of B-cell lymphoblastic lymphoma was established by immunohistochemical study of the biopsied kidney. The patient had an excellent response to the VDCLP protocol (vincristine, daunomycin, cyclophosphamide, asparaginase, and dexamethasone) with sustained remission. We recommend that lymphomatous infiltration be considered in patients presenting with unexplained acute kidney injury and enlarged kidneys.

Risk Factors for Severe Bleeding Complications in Percutaneous Renal Biopsy

Background: Percutaneous renal biopsy is essential for diagnosis of many renal diseases. Previous studies have revealed a variety of factors associated with bleeding complications of renal biopsy; however, data are not sufficient in the Chinese population. We aimed to investigate the risk factors for severe post‐biopsy bleeding events in a large cohort of Chinese patients. Materials and Methods: The data of patients who underwent percutaneous renal biopsy from January 2008 to December 2012 were collected. Severe bleeding complication was defined as requiring intervention, including blood transfusion or an invasive procedure (radiological or surgical) due to bleeding. Logistic regression analysis was used to assess risk factors. Results: Over the 5‐year period, 3,577 native kidney biopsies were performed. Severe bleeding complication occurred in 14 biopsies (0.39%). The patients with complications were older, had higher blood pressure, lower hemoglobin, lower platelet count and worse renal function. Multivariable logistic regression demonstrated that platelet level and the estimated glomerular filtration rate were independently associated with the risk of complications. Each 10 × 109/L increase of platelet count was associated with an 11% decrease of severe bleeding risk (odds ratio = 0.89; 95% CI: 0.80‐0.98; P = 0.02). Each 1 mL/minute/1.73 m2 increase of the estimated glomerular filtration rate was associated with a 4% decrease of severe bleeding risk (odds ratio = 0.96; 95% CI: 0.94‐0.99; P = 0.004). Conclusions: Patients with worse renal function and lower platelet counts had a higher risk of developing severe bleeding events after renal biopsy.

Invasive Pulmonary Aspergillosis in Patients With Antineutrophil Cytoplasmic Antibody Associated Vasculitis

Background and Aims:Invasive pulmonary aspergillosis (IPA) has been reported as a severe opportunistic infection in immunocompromised patients without neutropenia or cancer. Patients with antineutrophil cytoplasmic antibody associated vasculitis (AAV) with immunosuppressive treatment are susceptible to IPA, but only few cases were reported in the literature. We retrospectively analyze the clinical characteristics of our patients with IPA in AAV. Methods:Hospitalized patients with AAV who developed IPA were selected. Their clinical data were retrospectively reviewed and possible risk factors for development of IPA were investigated. Results:Seven of 157 patients with AAV were identified to have IPA. Two patients were classified as Wegener granulomatosis and 5 as microscopic polyangiitis with a mean age at 68.6 ± 10.9 years. After immunosuppressive therapy, 7 patients developed IPA within 2∼13 weeks. They had 1 or more risk factors increasing susceptibility to Aspergillus. Pre-existing chronic respiratory diseases were found in 5 patients. Despite intensive antifungal therapy, only 3 patients survived. The patients who died were older, with more severe lung injury and lower hemoglobin level. Conclusions:AAV patients with immunosuppressive therapy are susceptible to Aspergillus infection. Monitoring and prophylactic antifungal therapy should be recommended for patients at high risk.

Risk Factors of Pulmonary Thrombosis/Embolism in Nephrotic Syndrome

Background:Nephrotic syndrome is associated with an increased risk for thromboembolic complications. Until now, few studies have ever specified the risk of pulmonary thrombosis/embolism (PTE) in patients with nephrotic syndrome. In this study, we assessed the risk of PTE in a large cross-sectional study to identify risk factors in this population. Methods:Three hundred twelve patients with NS who had screened PTE through lung ventilation-perfusion scan were collected and analyzed. Multivariate Logistic regression was used to detect the independent risk factors for PTE. Logistic regression was used to identify the threshold value of D-dimer. Results:Sixty-five patients (20.8%) had PTE in individuals with NS. Elevated level of plasma D-dimer was identified as an independent risk factor of PTE on multivariate analysis (odds ratio = 1.54; 95% confidence interval: 1.27–1.88). While proteinuria at presentation and serum albumin were not associated with PTE after adjusted for D-dimer (P > 0.05). The cumulative probability of PTE was in a nearly linear association with the plasma D-dimer level even within the normal range. Based on the plasma D-dimer level, we had developed a concise model to predict the risk of pulmonary embolism using logistic curve. Conclusions:In adult patients with NS, high level of plasma D-dimer was closely associated with PTE, whereas proteinuria or serum albumin level was not in this study. Using plasma D-dimer level, we developed a concise model to predict the risk of PTE.

Clinical and pathological features of renal amyloidosis: An analysis of 32 patients in a single Chinese centre

Aim:  To summarize the clinical and pathological features of renal amyloidosis in order to achieve early diagnosis.