Huiping Chen

Obesity-Related Glomerulopathy in China: A Case Series of 90 Patients

BACKGROUND The epidemic of obesity has been paralleled by an increase in the incidence of chronic kidney disease. However, epidemiological data for obesity-related glomerulopathy (ORG) from developing countries, including China, are very limited. STUDY DESIGN Case series. ORG defined as body mass index (BMI) of 28.0 kg/m(2) or greater; urinary protein excretion of 0.4 g/24 h or greater, and glomerulomegaly (glomerular volume > 3.27 x 10(6) microm(3)) with or without focal segmental glomerulosclerosis (FSGS). SETTING & PARTICIPANTS 10,093 renal biopsy samples from patients obtained from February 2002 to November 2006 at the Research Institute of Nephrology, Nanjing University School of Medicine, China. PREDICTOR Obesity defined as a BMI of 28.0 kg/m(2) or greater. Subjects were divided into 3 groups: mild-obesity group with BMI of 28.0 to less than 30 kg/m(2), moderate-obesity group with BMI of 30 to less than 35 kg/m(2), and severe-obesity group with BMI of 35 kg/m(2) or greater. OUTCOMES & MEASUREMENTS Clinicoepidemiological and histopathologic characteristics of patients with ORG at the time of biopsy were described separately. RESULTS ORG was observed in 90 biopsy specimens (0.89%); frequency increased from 0.62% to 1.0% during the last 5 years (P = 0.02). Mean age was 37.5 +/- 9.3 (SD) years, 67% were men, mean BMI was 31.2 +/- 3.3 kg/m(2), waist circumference was 103 cm (range, 89.4 to 124 cm) in men and 96.5 cm (range, 88.5 to 113 cm) in women, waist-hip ratio was 0.95 +/- 0.07, and 100% had visceral obesity. Of the total, 49%, 37%, and 14% had mild, moderate, and severe obesity, respectively. Mean urinary protein excretion of subjects was 1.48 +/- 1.2 g/24 h; 51%, 39%, and 10% had proteinuria with protein of 0.4 to 1.0, 1.0 to 3.5, and greater than 3.5 g/d, respectively. Mean measured creatinine clearance (Ccr) was 109 +/- 32.2 mL/min/1.73 m(2), with 42%, 36%, and 22% with a Ccr greater than 120, 90 to 120, and less than 90 mL/min/1.73 m(2), respectively. Glucose dysmetabolism, insulin resistance, dyslipidemia, and hypertension were observed in 77%, 88%, 76%, and 63% of patients, respectively. FSGS was observed in 70%. Mean foot-process width was 534 +/- 176 nm. Foot-process fusion was seen in 36% of patients. Greater BMI was associated with greater proteinuria (P < 0.02), greater Ccr (P < 0.03), and greater foot-process width (P < 0.04). LIMITATIONS Inability to compute prevalence or incidence from case series. BMI was calculated at time of renal biopsy. CONCLUSIONS Most patients with ORG had mild obesity, visceral obesity, minor proteinuria, preserved Ccr, and FSGS.

Mercury-Induced Membranous Nephropathy: Clinical and Pathological Features

BACKGROUND AND OBJECTIVES Long-term contact with mercury may induce membranous nephropathy (MN); however, the clinical pathologic features and pathogenesis of mercury-induced MN have not been investigated. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS The present study retrospectively evaluated 11 cases of mercury-induced MN to analyze its causes and its clinical and pathologic features. RESULTS A total of 10 women and 1 man ages 15 to 45 years were enrolled in the present study. Mercury exposure was caused by mercury-containing pills (five patients), skin lightening cream (four patients), hair-dyeing agents (one patient), and mercury vapor (one patient). The duration of contact with mercury ranged from 2 to 60 months, and the urinary mercury concentrations were 1.5 to 50 times higher than reference values. All patients presented with proteinuria and normal renal function; three had nephrotic syndrome. Light microscopy revealed thickened glomerular basement membrane and mildly proliferative mesangial cells. Acute tubulointerstitial injury occurred in three patients. The immunofluorescence findings showed granular deposits of IgG and C3 along the glomerular capillary wall, mostly accompanied by deposits of C4 and C1q. IgG1 and IgG4 (predominantly IgG1) deposits were observed along the glomerular capillary loops. Nine patients reached complete remission in follow-up after withdrawal from mercury exposure. CONCLUSIONS Deposits of IgG1 subclasses in renal tissues indicated that the pathogenesis of mercury-induced MN differs from that of idiopathic MN. It is important that clinicians are aware that mercury exposure should be considered a possible cause of membranous nephropathy.

Long-term efficacy of tonsillectomy in Chinese patients with IgA nephropathy.

Background: To investigate the clinical efficacy of tonsillectomy on long-term clinical remission and renal survival of immunoglobulin A nephropathy (IgAN) patients in China. Methods: We performed a 130-month retrospective case-control study of 112 patients with idiopathic biopsy-diagnosed IgAN from 1983 to 1999. Fifty-four patients underwent tonsillectomy and 58 patients did not. The clinical remission rate during follow-up and variables to predict clinical remission were estimated by χ2 test and multivariate Cox regression analysis; renal survival was evaluated by Kaplan-Meier analysis. Results: Up to 2006, the follow-up period lasted 130 ± 50.3 months (60–276 months). The clinical remission rate was 46.3% in patients with tonsillectomy and 27.6% in those without tonsillectomy during follow-up. Multivariate analysis demonstrated that tonsillectomy was not an independent impact factor for renal clinical remission (p = 0.386). By Kaplan-Meier analysis, there was no significant difference in renal survival rate between patients with tonsillectomy and those without tonsillectomy (p = 0.059). Conclusion: The clinical remission rate in IgAN patients with tonsillectomy was higher than that in patients without tonsillectomy during follow-up. But within 130 months, it was difficult to find statistical difference in renal survival between IgAN patients with and without tonsillectomy.

Idiopathic IgA Nephropathy with Diffuse Crescent Formation

Objective: To investigate the clinicopathological features and outcome of idiopathic IgA nephropathy with diffuse crescent formation in Chinese patients. Methods: Twenty-five patients with diffuse crescentic IgA nephropathy (DCIgAN), 15 males and 10 females with median age of 28.5, and median disease duration of 5.1 months, were studied. Their clinical, laboratory and pathological features and outcome were investigated. Twenty-one were administered pulse immunosuppressive therapy, and 15 were followed up for more than 6 months. Results: 1.14% had total IgA nephropathy, and 16.4% total diffuse crescentic glomerulonephritis. Clinically, most of patients (88%) showed rapidly progressive glomerulonephritis associated with a high level of serum creatinine (418 ± 264 µmol/l). Gross hematuria was noted in 72%, hypertension in 64%, and nephrotic syndrome in 48%. Pathologically, except for diffuse crescent formation (a median 65% and range 50–95%), we observed segmental necrosis of glomerular capillaries in 60%, glomerular infiltrating cells in 48%, endothelial cells proliferation in 32%, and rupture of Bowmans’ capsule in 24%. Severe tubular interstitial damage was also found, tubular atrophy in 64%, interstitial fibrosis in 60%, diffuse interstitial infiltrating cells in 74%, and interstitial vasculitis in 40%. Immunopathologically, four phenotypes were observed; however, IgA associated with IgM deposition was higher than that in patients with general IgA nephropathy (IgAN). In addition, the infiltrating CD4+, CD8+, CD68+ and PCNA+ cells in renal tissue were significantly high compared with that in controls. In a follow-up study, 66.7% of patients had life-sustaining renal function, 4 of them had normal range of serum creatinine (<124 µmol/l), and only 5 were dialysis-dependent. Conclusions: The patients with crescentic IgA nephropathy mostly show rapidly progressive nephritis associated with more severe pathological changes including glomerular, tubular interstitial and vascular lesions than in patients with general IgAN. The infiltrates in glomeruli may contribute to the crescentic formation, and the intensive immune suppressing treatment is useful to improve renal damage in patients with DCIgAN.

The fate of glomerular mesangial IgA deposition in the donated kidney after allograft transplantation

Objective:  To investigate the fate of the mesangial IgA deposits in the donor kidney after allograft transplantation.

Effects of mycophenolate mofetil for patients with crescentic lupus nephritis.

Objective:  To compare the effects, relapse ratio and outcomes between mycophenolate mofetil (MMF) and pulse intravenous cyclophosphamide (CTX) for the induction therapy in patients with crescentic lupus nephritis.

Circulating Anti-endothelial Cell Antibodies Are Associated with Poor Outcome in Renal Allograft Recipients with Acute Rejection

BACKGROUND AND OBJECTIVES Anti-endothelial cell antibody (AECA) can cause hyperacute rejection and immediate graft loss after renal transplantation; however, its prevalence and significance during acute rejection are unknown. Previous studies suggested that AECA may be detected in recipients with acute vascular rejection (AVR). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We retrospectively analyzed 653 cadaveric renal transplant recipients; circulating AECA was positive in 13 of 47 cases of AVR; another two cases of hyperacute rejection also had detectable AECA. Twenty-six cases of AVR without circulating AECA were selected as controls. RESULTS AECA-positive AVR usually occurred within 1 yr after transplantation and mostly was resistant to steroid treatment. Compared with the control group, the AECA-positive group was associated with a significantly lower 1-yr graft survival rate (46.7 versus 80.5%; P = 0.038), and more patients had histologic interstitial plasma cell infiltration (53.8 versus 11.5%; P = 0.005). More patients with AECA-positive AVR experienced another one or more episodes of acute rejection during 1 yr of follow-up (75.0 versus 13.0%; P = 0.003). AECA-positive AVR with C4d deposition in peri-tubular capillaries had the worst outcome in this cohort, and it accounted for 38.5% graft loss in AVR. AECA in turn accounted for 71.4% of graft loss in C4d(+) AVR. CONCLUSIONS Circulating AECA is associated with poor outcome in renal allograft recipients with acute rejection and should be monitored regularly.

Detectable circulating antiendothelial cell antibodies in renal allograft recipients with C4d-positive acute rejection: a report of three cases.

It is suggested that non-HLA endothelial antigens may also cause C4d-positive acute rejection, but this is very rare. We report on three renal allograft recipients who developed C4d-positive acute rejection with detectable circulating antiendothelial cell antibodies (AECAs). All patients had severe dialysis-dependent graft dysfunction. Histologic manifestations include neutrophils infiltration on peritubular capillaries and glomeruli. Endoarteritis can be seen in all the patients. Two patients lost grafts after the rescue therapy including immunoadsorption, mycophenolate mofetil with or without tacrolimus. The titer variation of AECAs might be associated with the graft outcome. In patients those who lost grafts, AECAs titer increased from 1:10 to 1:80 in one patient, and was kept positive during the treatment in the other patient. In the recovered patient, however, the titer became negative from 1:40. From our report, it appears that persisting circulating AECAs during the rescue treatment of C4d-positive acute rejection may be associated with a poor outcome.

Renal Involvement in Non-Hodgkin Lymphoma: Proven by Renal Biopsy

Aims To determine the spectrum of renal lesions in patients with kidney involvement in non-Hodgkins lymphoma (NHL) by renal biopsy. Methods The clinical features and histological findings at the time of the renal biopsy were assessed for each patient. Results We identified 20 patients with NHL and renal involvement, and the diagnosis of NHL was established following the kidney biopsy in 18 (90%) patients. The types of NHL include the following: chronic lymphocytic leukemia/small lymphocytic lymphoma (n = 8), diffuse large B-cell lymphoma (n = 4), T/NK cell lymphoma (n = 3), lymphoplasmacytic lymphoma (n = 2), cutaneous T-cell lymphoma (n = 1), mucosa-associated lymphoid tissue lymphoma (n = 1) and mantle cell lymphoma (n = 1). All presented with proteinuria, and 15 patients had impaired renal function. The pathological findings included (1) membranoproliferative glomerulonephritis-like pattern in seven patients; (2) crescent glomerulonephritis in four; (3) minimal-change disease in three, and glomeruli without specific pathological abnormalities in three; (4) intraglomerular large B-cell lymphoma in one; (5) intracapillary monoclonal IgM deposits in one; (6) primary diffuse large B-cell lymphoma of the kidneys in one; and (7) lymphoma infiltration of the kidney in eight patients. Conclusion A wide spectrum of renal lesions can be observed in patients with NHL, and NHL may be first proven by renal biopsies for evaluation of kidney injury or proteinuria. Renal biopsy is necessary to establish the underlying cause of renal involvement in NHL.

Clinical–Morphological Features and Outcomes of Lupus Podocytopathy

BACKGROUND AND OBJECTIVES Lupus podocytopathy, which is characterized by diffuse foot process effacement without peripheral capillary wall immune deposits and glomerular proliferation, has been described in SLE patients with nephrotic syndrome in case reports and small series. This study aimed to better characterize the incidence, clinical-morphologic features, and outcomes of such patients from a large Chinese cohort. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Lupus podocytopathy was identified from 3750 biopsies of SLE patients obtained from 2000 to 2013 that showed mild glomerular histology in patients with a clinical sign of nephrotic syndrome. The biopsy results were divided into three groups: glomerular minimal change, mesangial proliferation, and FSGS. RESULTS Fifty (1.33%) cases were identified as lupus podocytopathy and included minimal change in 13 cases, mesangial proliferation in 28 cases, and FSGS in nine cases. Extensive foot process effacement appeared in all the biopsies and mesangial electron-dense deposits were present in 47 biopsies. All patients demonstrated nephrotic syndrome, and the median proteinuria was 5.72 g/24 h (interquartile range [IQR], 3.82, 6.92). Seventeen (34%) cases presented with AKI. Forty-seven (94%) patients achieved remission after immunosuppressive therapy for a median time of 4 weeks (IQR, 2, 8). Compared with the patients with minimal change and mesangial proliferation, patients with FSGS showed significantly higher incidence of AKI and severe tubule-interstitial injury and a much lower complete remission rate. During follow-up of a median of 62 (IQR, 36, 84) months, renal relapses occurred in 28 (59.6%) patients. No patient died or developed ESRD. CONCLUSIONS The findings from this cohort study suggest that lupus podocytopathy may represent a special entity of lupus nephritis with distinct clinical-morphologic features. The differences in AKI incidence, tubular injury severity, and response to treatment between the patients with minimal change/mesangial proliferation and those with FSGS patterns indicate two different subtypes of lupus podocytopathy.