Blandine Laurent

Predicting the Risk for Dialysis or Death in IgA Nephropathy

For the individual patient with primary IgA nephropathy (IgAN), it remains a challenge to predict long-term outcomes for patients receiving standard treatment. We studied a prospective cohort of 332 patients with biopsy-proven IgAN patients followed over an average of 13 years. We calculated an absolute renal risk (ARR) of dialysis or death by counting the number of risk factors present at diagnosis: hypertension, proteinuria ≥1 g/d, and severe pathologic lesions (global optical score, ≥8). Overall, the ARR score allowed significant risk stratification (P < 0.0001). The cumulative incidence of death or dialysis at 10 and 20 years was 2 and 4%, respectively, for ARR=0; 2 and 9% for ARR=1; 7 and 18% for ARR=2; and 29 and 64% for ARR=3, in adequately treated patients. When achieved, control of hypertension and reduction of proteinuria reduced the risk for death or dialysis. In conclusion, the absolute renal risk score, determined at diagnosis, associates with risk for dialysis or death.

The Use of the Oxford Classification of IgA Nephropathy to Predict Renal Survival

BACKGROUND AND OBJECTIVES A new classification for IgA nephropathy was recently proposed, namely the Oxford classification. It established specific pathologic features that predict the risk of progression of renal disease. This classification needs validation in different patient populations. We propose a retrospective study to evaluate the predictive value of the Oxford classification on renal survival defined by doubling creatinine or end-stage renal disease in patients with IgA nephropathy. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We included 183 patients with primary IgA nephropathy diagnosed between 1994 and 2005. Mean follow-up time was 77 months. Doubling creatinine occurred in 20% of the patients, and end-stage renal disease occurred in 16%. The biopsies were revisited to apply the Oxford classification. The influence of pathologic features on renal survival was analyzed in univariate and multivariate models. RESULTS In univariate time-dependent analyses, tubular atrophy/interstitial fibrosis, segmental glomerulosclerosis, and endocapillary hypercellularity strongly impacted doubling creatinine or end-stage renal disease. On the contrary, mesangial hypercellularity was not associated with renal outcome. In the multivariate model, only estimated GFR at baseline was a risk factor, pathologic lesions having no independent influence. CONCLUSIONS We confirm the usefulness of the Oxford classification to establish the renal prognosis of patients with IgA nephropathy, although renal function at baseline seems to be of a greater importance than pathologic lesions.

Predicting glomerular filtration rate in kidney transplantation: are the K/DOQI guidelines applicable?

The kidney disease outcomes quality initiative (K/DOQI) guidelines introduced a classification of chronic kidney disease (CKD) based on the level of kidney function. In order to predict the glomerular filtration rate (GFR), they specifically recommended the use of the modification of diet in renal disease (MDRD) study and Cockcroft–Gault (C–G) equations.

Antithymocyte globulin (ATG) induction therapy and disease recurrence in renal transplant recipients with primary IgA nephropathy.

Recurrence of primary IgA nephropathy after renal transplantation is clearly a time-dependent event, justifying the use of Kaplan-Meier and Cox regression analyses to sort the significant risk factors. In this retrospective study, we focused on the potential role of induction immunosuppressive therapy. We studied 116 renal transplantation (84 males, 112 cadaveric donors, 95 first grafts, mean age at Tx=46.1 years) who received, as induction, antithymocyte globulin (ATG) in 29, anti-CD25 in 35, and none in 52, associated with different maintenance therapy overtime. The 10-year cumulative recurrence rate was overall 36%, but only 9% after ATG induction when compared with 41% without induction (P=0.001). Multivariate Cox regression confirmed that ATG was protective with a 80% reduction in relative risk (P=0.01). In conclusion, this important finding needs to be confirmed in a prospective trial and if so will have major implication.

A randomized prospective study comparing low-dose OKT3 to low-dose ATG for the treatment of acute steroid-resistant rejection episodes in kidney transplant recipients

Abstract Acute steroid‐resistant rejection episodes in kidney allograft recipients require treatment with antilymphocyte antibodies. Monoclonal anti‐CD3 and polyclonal antilymphocyte antibodies have been widely used but seldom compared. Recent data have suggested that these antibodies could be used at reduced doses without jeopardizing their efficacy. In this study, we randomized renal transplant recipients who encountered a first acute steroid‐resistant rejection episode to low‐dose ATG or low‐dose OKT3 treatment. Sixty patients were enrolled in the study. They received prophylactic immunosuppression with cyclosporin, azathioprine, and prednisolone. Treatment of biopsy‐proven rejection consisted of a 10–day course of either ATG (n= 31) or OKT3 (n= 29). The total ATG dose was 484 ± 110 mg, i.e., 0.75 mg/kg per day. The total OKT3 dose was 32 ± 4 mg, i. e., 0.05 mg/kg per day. We compared reversion of rejection, side effects, immunodepression, and graft function. Reversion of rejection was similar in the two groups, although we noted a trend in favor of ATG. Results were 3% vs 10% early graft failures, 13% vs 23% overall graft failures, 28% vs 38% 3‐month actuarial incidence of rebound rejection, and 89% vs 81% 1‐year graft survival rate in the ATG and OKT3 groups, respectively. Tolerance was worse in the OKT3 group due to the first‐dose syndrome. Infections and cancers occurred with the same frequency. ATG resulted in a deeper and longer decrease in peripheral lymphocyte subsets. Graft function was similar in the two groups. We conclude that low‐dose ATG and low‐dose OKT3 are equally effective in reversing steroid‐resistant acute rejection. Tolerance was better with ATG, which also gave a more potent and longlasting immunodepression. The use of reduced doses of ATG and OKT3 did not appear to lessen their efficacy.

Membranoproliferative Glomerulonephritis with Subendothelial Deposits (Type 1) Associated with Hepatitis G Virus Infection in a Renal Transplant Recipient

Background: Infection with hepatitis B virus (HBV) or hepatitis C virus (HCV) is a well-known etiology for membranoproliferative glomerulonephritis (MPGN) with subendothelial deposits (MPGN type 1). Material and Methods: The newly discovered hepatitis G virus (HGV) is currently under active investigation. We report the first case of de novo MPGN type 1 associated with HGV infection in a young male renal transplant recipient who manifested glomerulonephritis (GN) with proteinuria 7 years after transplant, and whose original disease was chronic obstructive pyelonephritis secondary to nephrolithiasis. Results: Serum markers for HBV and HCV infections were negative. HGV infection was detected by specific double-nested reverse transcriptase-polymerase chain reaction (RT-PCR) in sera (positive HGV viremia) 2.5 years after renal transplantation. By specific in situ RT-PCR, the presence of the HGV genome was detected in peripheral blood mononuclear cells and in the kidney biopsy (glomeruli and tubules), but not in the liver. Conclusion: This report adds new information on the role of HGV infection in the occurrence of de novo GN (MPGN type 1) in renal transplantation.

Validation of the absolute renal risk of dialysis/death in adults with IgA nephropathy secondary to Henoch-Schönlein purpura: a monocentric cohort study

BackgroundWe established earlier the absolute renal risk (ARR) of dialysis/death (D/D) in primary IgA nephropathy (IgAN) which permitted accurate prospective prediction of final prognosis. This ARR was based on the potential presence at initial diagnosis of three major, independent, and equipotent risk factors such as hypertension, quantitative proteinuria ≥ 1 g per day, and severe pathological lesions appreciated by our local classification scoring ≥ 8 (range 0–20). We studied the validity of this ARR concept in secondary IgAN to predict future outcome and focused on Henoch-Schönlein purpura (HSP) nephritis.MethodsOur cohort of adults IgAN concerned 1064 patients with 101 secondary IgAN and was focused on 74 HSP (59 men) with a mean age of 38.6 at initial diagnosis and a mean follow-up of 11.8 years. Three major risk factors: hypertension, proteinuria ≥1 g/d, and severe pathological lesions appreciated by our global optical score ≥8 (GOS integrated all elementary histological lesions), were studied at biopsy-proven diagnosis and their presence defined the ARR scoring: 0 for none present, 3 for all present, 1 or 2 for the presence of any 1 or 2 risk factors. The primary end-point was composite with occurrence of dialysis or death before (D/D). We used classical statistics and both time-dependent Cox regression and Kaplan-Meier survival curve methods.ResultsThe cumulative rate of D/D at 10 and 20 years post-onset was respectively 0 and 14% for ARR = 0 (23 patients); 10 and 23% for ARR = 1 (N = 19); 27 and 33% for ARR = 2 (N = 24); and 81 and 100% (before 20 y) in the 8 patients with ARR = 3 (P = 0.0007). Prediction at time of diagnosis (time zero) of 10y cumulative rate of D/D event was 0% for ARR = 0, 10% for ARR = 1, 33% for ARR = 2, and 100% by 8.5y for ARR = 3 (P = 0.0003) in this adequately treated cohort.ConclusionThis study clearly validates the Absolute Renal Risk of Dialysis/Death concept in a new cohort of HSP-IgAN with utility to individual management and in future clinical trials.

The podocin mutation R229Q and early recurrence (within the first year) of glomerular disease after renal transplantation.

BACKGROUND Podocin is a key protein involved in the pathogenesis of steroid-resistant nephrotic syndrome and/or focal segmental glomerulosclerosis (FSGS) and is characterized by a high rate of early recurrence after renal transplantation (RTx) in children and adults. MATERIAL AND METHODS We studied 206 RTx adult recipients: 187 with a diagnosis of glomerular nephropathy, GN (biopsy-proven in 149, clinical in 38), plus 19 with unknown diagnosis as original kidney disease (OKD), the NPHS2 gene polymorphism, G755A, and correlated with the presence of early recurrence of OKD within the first year (proteinuria over 1 g/day and graft-biopsy proven). RESULTS The A allele podocin gene mutation frequency was 3.4% (14/412) overall - 7.1% (4/56) in FSGS as expected, but surprisingly 5.7% (6/106) in IgA nephropathy. Fifty recipients (24.3%) developed proteinuria >1 g/d, with 12 recipients demonstrating early clinico-pathological recurrence by 1 year (5.8%) with 5/28 in FSGS, 2/53 in IgAN, 2/14 in membranoproliferative GN (with 1 graft loss within the first year), 1/19 in crescentic GN, 1/19 in unknown disease, and 1/38 in clinical GN. Only 2 recurrent patients (both with FSGS) had the R229Q podocin mutation (16.7%). CONCLUSIONS The podocin mutation R229Q may play a role in the pathogenesis of FSGS and in early recurrence after transplantation, but does not allow accurate prediction of recurrence or the associated potential for prevention.

Anti-phospholipase A2 receptor antibody levels at diagnosis predicts spontaneous remission of idiopathic membranous nephropathy

Abstract Background: The diagnostic role of circulating anti-phospholipase A2 receptor antibodies (anti-PLA2R Abs) is now well recognized in idiopathic membranous nephropathy (iMN). These Abs could also be interesting as predictors of clinical outcome. In this study, we explored the prognostic value of anti-PLA2R Abs measured in a cohort of iMN patients, with a special focus on their ability to detect patients achieving spontaneous remission. Methods: All adult patients with biopsy-proven iMN diagnosed between 1978 and 2007 were retrospectively screened in our centre. Using a validated enzyme-linked immunosorbent assay, levels of anti-PLA2R Abs were measured from serum samples obtained at the time of renal biopsy and stored at −80°C until processing. Clinical data on disease activity, treatments and outcomes were collected by reviewing patients’ medical records. The association between anti-PLA2R Ab titres and clinical activity/outcome was assessed by Cox proportional hazard and Kaplan–Meier methods. Results: In this retrospective study, 68 patients were included in the final analysis (median follow-up of 81 months). No significant association was found between anti-PLA2R Ab titres at diagnosis with baseline proteinuria, baseline estimated glomerular filtration rate or chronic kidney disease progression. Spontaneous remission was observed in 22% of patients. Ab titres were significantly and gradually correlated in a dose–response manner with the likelihood of spontaneous remission. Conclusions: While Ab titres measured at diagnosis were not found to predict the activity of iMN, evaluation of anti-PLA2R Ab titres might prove useful in the early identification of patients likely to achieve spontaneous remission.