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Thrombotic microangiopathy (TMA) is one of the hallmark vascular lesions of antiphospholipid syndrome nephropathy (APSN). These lesions are at high risk of recurrence after kidney transplantation. The complement pathway is thought to be active in this process. We used eculizumab to treat three consecutive kidney transplant recipients with posttransplant TMA due to APSN recurrence that was resistant to plasmapheresis and explored the complement deposition and apoptotic and vascular cell markers on the sequential transplant biopsies. Treatment with eculizumab resulted in a rapid and dramatic improvement of the graft function in all three patients and in improvement of the TMA lesions within the graft. None of these patients had TMA flares after eculizumab was withdrawn. At the time of TMA diagnosis, immunofluorescence studies revealed intense C5b-9 and C4d depositions at the endothelial cell surface of the injured vessels. Moreover, C5b-9 colocalized with vessels exhibiting a high rate of apoptotic cells. Examination of sequential biopsies during eculizumab therapy showed that TMA lesions, C4d and apoptotic markers were rapidly cleared but the C5b-9 deposits persisted for several months as a footprint of the TMA. Finally, we noticed that complement inhibition did not prevent the development of the chronic vascular changes associated with APSN. Eculizumab seems to be an efficient method for treating severe forms of posttransplant TMA due to APSN recurrence. Terminal complement inhibition does not prevent the development of chronic APSN.

C4d on erythrocytes (EC4d), C4d peritubular capillary deposition (PTC-C4d) staining and histology were compared in a cross-sectional cohort of 146 renal allograft biopsies (132 patients). EC4d levels paralleled PTC-C4d staining, but were more predictive of peritubular capillaritis (PTC). Donor-specific antibodies (DSA), PTC-C4d, EC4d and PTC were analyzed in an independent longitudinal follow-up cohort (96 biopsies, 76 patients). Seventy-six samples were PTC and EC4d concordant, 11 positive and 65 negative, 7 PTC-EC4d+ and 13 PTC+EC4d-. EC4d levels were related to DSA occurrence. With ABMR defined by PTC and DSA, all apparently discordant patients, EC4d negative, were correctly reassigned comparing EC4d level curves with rejection kinetics, with positive EC4d samples predating biopsy or late biopsies compared with ABMR flare-ups. All EC4d-positive patients without PTC or DSA had permanent high EC4d levels unrelated to rejection. EC4d was more abundant in PTC-positive (mean = 108.5%± 3.4; n = 50) than PTC-negative samples (mean = 88.1%± 1.3; n= 96; p < 0.0001). Sensitivity, specificity, positive predictive value and negative predictive value of PTC-C4d and EC4d for PTC were, respectively, 75%, 79%; 64%, 76% (p < 0.05); 28%, 46% (p < 0.05) and 93%, 94%. Values were similar for DSA. A noninvasive blood test, EC4d, and particularly longitudinally monitoring EC4d levels, may increase surrogate ABMR testing options.

International audience; Screening renal biopsies (RB) may assess early changes of interstitial fibrosis (IF) after transplantation. The aim of this study was to quantify IF by automatic color image analysis on sequential RB. We analyzed RB performed at day (D) 0, month (M) 3 and M12 from 140 renal transplant recipients with a program of color segmentation imaging. The mean IF score was 19 ± 9% at D0, 27 ± 11% at M3 and 32 ± 11% at M12 with a 8% progression during the first 3 months and 5% between M3 and M12. IF at M3 was correlated with estimated glomerular rate (eGFR) at M3, 12 and 24 (p < 0.02) and IF at M12 with eGFR at M12 and 48 (p < 0.05). Furthermore, IF evolution between D0 and M3 (ΔIFM3-D0) was correlated with eGFR at M24, 36 and 48 (p < 0.03). IF at M12 was significantly associated with male donor gender and tacrolimus dose (p = 0.03). ΔIFM3-D0 was significantly associated with male donor gender, acute rejection episodes (p = 0.04) and diabetes mellitus (p = 0.02). Thus, significant IF is already present before transplantation. IF evolution is more important during the first 3 months and has some predictive ability for change in GFR. Intervention to decrease IF should be applied early, i.e. before 3 months, after transplantation.

The results of our last 5 years activity in kidney transplantation clearly show that it is possible to perform high-risk transplantations with very acceptable results: ECD kidneys, dual transplantation, recipients with DSAs. In depth statistical analysis of these data should allow a clearer definition of the best strategies to use in these situations.

Nephrotoxicity of calcineurin inhibitors (CNIs) is an acute, reversible and chronic, irreversible pathology. Histologically, acute nephrotoxicity manifests as hemodynamic modifications caused by vasoconstriction of the essentially afferent arterioles resulting in a drop in the glomerular filtration rate. Chronic nephrotoxicity is characterized by arteriolar hyalinosis resulting in a variety of tubulointerstitial and glomerular lesions with an essentially ischemic mechanism. However, these histological lesions, whether chronic or acute, are not specific of CNI toxicity and can be seen in the course of many pathological circumstances in kidney transplantation. This absence of specificity makes the histological diagnosis of CNI nephrotoxicity difficult. In addition, the individual risk of developing CNI nephrotoxicity, difficult to predict based solely on the pharmacokinetic parameters of systemic CNI exposure, also involves local exposure (CNI concentrations in the graft) modulated by several, notably pharmacogenetic factors. The difficulty of diagnosing CNI nephrotoxicity and the interindividual variability of its risk require development of new diagnostic tools so that the patients at highest risk of developing severe CNI nephrotoxicity lesions, in whom minimization protocols would produce the best risk-benefit ratio, can be identified.

Hemolytic uremic syndrome (HUS) associated with anti-Factor H (anti-FH) autoantibodies is a recently described pathophysiological entity. Monitoring of anti-FH IgG titer may be a sensitive marker of disease activity and guide treatment to eliminate circulating anti-FH antibodies. We report here a case of atypical HUS (aHUS) in which anti-FH autoantibodies were detected during the course of a fifth kidney transplant, 30 years after the first flare of aHUS. This exceptional case suggests that early, specific management based on immunosuppressive therapy and plasma exchanges monitored by anti-FH IgG titer may result in long-term graft survival.

No treatment has consistently induced long-term remission of proteinuria in adult patients with focal segmental glomerulosclerosis (FSGS) recurrence after kidney transplantation. We undertook an open-label, nonrandomized pilot trial of intensive and prolonged treatment of FSGS recurrence. Over an 18-month period, 10 adult kidney transplant recipients with FSGS recurrence received concomitantly high-dose steroids, intravenous cyclosporine for 14 days followed by oral cyclosporine therapy, and an intensive and prolonged course of plasma exchanges (PE). We compared this treatment with those of a control group of 19 patients with a FSGS recurrence transplanted between 1997 and 2005. Complete, rapid (mean 23 +/- 7 days) and sustained remission was obtained in 9/10 patients (90%) as opposed to 27% in the control group. At month 3 and month 12, proteinuria was 0.16 g/day (range 0.05-0.3 g/day) and 0.19 g/day (range 0.05-1 g/day) respectively. Only one patient remained in partial remission at month 12 but he had already lost two previous grafts due to FSGS recurrence. PEs were stopped at month 9 in all patients except for the patient with a partial remission who remains PE-dependent. This small pilot study provides very encouraging results demonstrating that this treatment rapidly achieves complete and sustained remission in a high proportion of patients.

Renal biopsy is an invaluable tool used for the monitoring of grafts and the management of their survival. Since 1993, thanks to research on biopsy tissues that enabled to distinguish the different types of rejection and to find markers of reversible or irreversible rejection, a classification of renal lesions has been established to achieve the regularly updated Banff classification. The last in date (2005) has defined the antibody-mediated chronic rejection, forsaken the term "chronic allograft nephropathy" and described a new class with interstitial fibrosis and tubular atrophy (IF/TA). Systematic or screening biopsies allow revealing infraclinical rejection lesions before any renal function degradation, better understanding of allograft nephropathy pathophysiology, confirming the diagnostic, but also displaying other more specific lesions that could benefit from a treatment. However, the interest of biopsies is limited by interpretation problems and risks for the patient.

The effects of posttransplant prophylactic intravenous immunoglobulin (IVIg) were investigated in renal transplant recipients at high immunological risk. Thirty-eight deceased-donor kidney transplant recipients with previous positive complement-dependent cytotoxicity crossmatch (n=30), and/or donor-specific anti-HLA antibodies (n=14) were recruited. IVIg (2 g/kg) was administrated on days 0, 21, 42 and 63 with quadruple immunosuppression. Biopsy-proven acute cellular and humoral rejection rates at month 12 were 18% and 10%, respectively. Glomerulitis was observed in 31% and 60% of patients at months 3 and 12, respectively, while allograft glomerulopathy rose from 3% at month 3 to 28% at 12 months. Interstitial fibrosis/tubular atrophy increased from 18% at day 0 to 51% and 72% at months 3 and 12 (p0.0001). GFR was 50 +/- 17 mL/min/1.73 m(2) and 48 +/- 17 mL/min/1.73 m(2) at 3 and 12 months. PRA decreased significantly after IVIg (class I: from 18 +/- 27% to 5 +/- 12%, p0.01; class II: from 25 +/- 30% to 7 +/- 16%, p0.001). Patient and graft survival were 97% and 95%, respectively and no graft was lost due to rejection (mean follow-up 25 months). In conclusion, prophylactic IVIg in high-immunological risk patients is associated with good one-year outcomes, with adequate GFR and a profound decrease in PRA level, but a significant increase in allograft nephropathy.

Vasculitic lesions are defined by necrosis of the vascular wall with perivascular inflammatory infiltrates. Secondary forms of vasculitis are observed in some systemic diseases, after infections, secondary to drugs or to malignancies. Usually, these secondary forms are characterised by the presence of immunoglobulin and complement deposits and thus probably caused by immune complex deposits. Conversely, necrotizing vasculitis occurring without known causal factor are named primary vasculitis, are not associated with immune deposits. Wegener's granulomatosis, microscopic polyangitis, Churg and Strauss syndrome and the isolated form of necrotizing and crescent glomerulonephritis are closely associated with the anti-neutrophil cytoplasm auto-antibodies (ANCA). The two main auto-antigen targets recognised by ANCA are lysosomal enzymes, proteinase 3 and myeloperoxidase, both contained in azurophilic granules of polymorphonuclear neutrophils and in primary lysosomes of monocytes. It has been demonstrated that ANCA antigens are expressed at the neutrophil (and monocyte) membrane after preactivation and are accessible to antibodies. Thus, ANCA may amplify neutrophils and monocyte activation. However, the causal or induced nature of anti-neutrophil auto-immunity in vasculitis remains unknown.

These antibodies are specific for antigens in the cytoplasm of neutrophils. The main antigenic targets are proteinase 3(PR3) and myeloperoxydase (MPO) but other targets have been described without determinant conclusions for clinical practice. Staining patterns can be distinguished by an indirect immunofluorescence test (IFI), in which ethanol fixed neutrophils from healthy donors are incubated with patient's sera. Two patterns are distinguished: cytoplasmic pattern (c-ANCA) and perinuclear pattern (p-ANCA). When ANCA are detected by IFI, from a practical point of view, anti -MPO and anti-PR3 antibodies are tested. ANCA have been strongly associated with a spectrum of necrotizing small vessel vasculitides that includes Wegener's granulomatosis, microscopic polyangiitis, Churg and Strauss syndrome, pauci-immune focal necrotizing and crescentic glomerulonephritis. ANCA are a diagnosic marker and useful for the follow-up of the patients. ANCA can be observed in other pathologies: rhumatismal autoimmune diseases, inflammatory gut diseases, after drugs (hydralazine, minocycline, propylthiouracil), after silical exposition, infections (cystic fibrosis, endocarditis, HIV infection). The specificity is different and rarely anti-MPO. The ANCA role for the development of vasculitis is not completely elucidated. Some arguments are against a primary role of ANCA in the development of vasculitis. Certainly, amplification role for neutrophil activation is demonstrated but the primary event responsible of neutrophil activation is not yet defined.

Cyclosporine A (CsA) nephrotoxicity is a nonimmunologic factor of chronic allograft dysfunction (CAD) in kidney transplant recipients. Mycophenolate mofetil (MMF) may allow CsA dosage reduction or even complete withdrawal in selected populations with CsA nephrotoxicity or CAD. The aim of the present study was to evaluate the efficacy and safety of CsA withdrawal after azathioprine (AZA)-MMF conversion in a population of stable renal transplant recipients.Twenty-eight first cadaver kidney recipients were included. AZA was then discontinued, MMF was introduced and after 4 months CsA was completely withdrawn. All patients underwent inuline clearance measurement and renal biopsy at inclusion and at the end of the follow-up (40 wk).CsA was completely discontinued in 20 patients. No patient lost his graft during the study period, but 1 patient experienced a reversible acute rejection episode. Inuline clearance improved significantly in the whole series. At the end of follow-up, histological worsening was observed in 50% of patients without any specific risk factor. In these patients, inuline clearance did not improve. Systolic blood pressure, the need for anti-hypertensive drugs and HDL cholesterol improved.In stable kidney transplant recipients, CsA withdrawal after AZA replacement by MMF switch was safe with regard to acute rejection. It improved blood pressure and the lipid profile, but, in 50% of patients was associated with histologic deterioration.

Rheumatoid purpura or Henoch-Schönlein syndrome is an IgA vasculitis affecting small vessels. The acute disease progresses by successive flare-ups of limited duration. Long-term prognosis depends mainly on the degree of initial renal damage. A review of the literature shows that renal involvement occurs in about 33% of children and 63% of adults with rheumatoid purpura. The most typical manifestation is segmentary focal glomerulonephritis, always associated with granulous IgA deposits in the mesangium. When renal signs are severe enough to warrant renal biopsy (generally at urine protein1 g/d and/or organic renal failure) the risk of developing chronic renal failure is 18% in children and 28% in adults. The best prognostic features are histological. The percentage of crescents, the presence of interstitial fibrosis and the presence of dense sub-epithelial deposits are correlated with risk of chronic renal failure. This risk is high (47%) in children with crescents in more than half the glomeruli. In adults, the percentage of crescents associated with unfavorable course appears to be lower than 50%. Predictions are only valid if no further renal flare-up occurs. In addition, histology cannot precisely predict the course of persistent renal sequelae. The severity of sequelae determines the risk and the rapidity of developing chronic renal failure. It is thus recommended to follow patients with Henoch-Schönlein nephritis for long periods.

Focal and segmental glomerulosclerosis (FSGS) is one of the most common and non-specific patterns of glomerular injury encountered in human renal biopsies. The primary form can be considered when there is a nephrotic syndrome without other causes. The majority of authors agree that podocytes play a role in the development of segmental glomerulosclerosis. The lesion begins with cell hypertrophy, foot process effacement, cell body attenuation, pseudocyst formation, cytoplasmic overload with reabsorption droplets and finally detachment of the glomerular basement membrane (GBM). When the GBM is denuded, it comes into contact with the parietal epithelium and parietal epithelial cells will attach to the GBM, leading to a synechia and, finally, sclerosis. Along this zone, parietal epithelial cells rest on hyalin material. Occlusion and collapse of a group of capillaries is observed, with inclusion of foam cells and hyalin deposits. The origin of primary FSGS has not yet been elucidated. Genetic, racial and developmental factors, macrophages, viral factors and circulating factors are being explored and give encouraging results.

Background. The aim of the present study was to describe the histologic features disclosed by protocol kidney transplant biopsies in patients who experienced neither acute rejection nor acute renal failure during the 2 years after transplantation. Methods. We studied 10 recipients of HLA-identical kidneys from living-related donors and 31 recipients of cadaveric kidneys. They were selected because, during the 2 years after transplantation, they did not experience clinical acute or chronic rejection, their renal function was normal and stable, and they underwent a protocol kidney biopsy at 3 months and at 2 years after transplantation. Results. Histologic chronic allograft nephropathy was present in 25% of patients at 3 months and in 50% at 2 years, but was absent in the recipients of HLA-identical kidneys. Histologic worsening was associated with increased donor age, the presence of asymptomatic grade I acute rejection at 3 months, and an increased cyclosporine trough level. Conclusions. Protocol biopsies contribute important information that could be used to improve the prophylaxis of chronic allograft nephropathy.

Renal granulomas are a relatively infrequent finding in the kidney biopsy. They have been described in a number of syndromes such as Wegener's granulomatosis, anti-GBM glomerulonephritis, and sarcoidosis, and are commonly believed to be indicative of a fulminant clinical course. In leading textbooks, diverse definitions of renal granulomas are presented, which has led to controversies in identifying them. This, in combination with their rare occurrence, makes it difficult for the general pathologist to identify them. We present the clinical data of 16 patients with renal granulomas, from a total group of 157 patients with systemic vasculitis. Their renal functioning was not significantly different from the other 141 patients in whose renal biopsies renal granulomas were present. Furthermore, we present two practical definitions for the recognition of renal granulomas in the kidney biopsy, and we show a number of examples of their various histopathological shapes.

Antiglomerular basement membrane (anti-GBM) glomerulonephritis (GN) is rare and is characterized by rapidly progressive GN with IgG linear deposits along the GBM in immunofluorescence study and circulating anti-GBM antibodies. This form of GN usually occurs without previous renal disease, but some cases of membranous GN have been reported with secondary development of antiGBM disease [1,2]. Administration of drugs such as D-penicillamine, which are useful for the treatment of rhumatoid arthritis, can be complicated by glomerular disease, more Fig. 2. Linear diffuse IgG deposits on the residual GBM precisely membranous GN, but also minimal-change (Immunofluorescence, ×1000). GN, and crescentic GN [3–5]. Mechanisms for the

Repeat renal biopsies and serial serum creatinine measurements were done in 36 adults who were treated for steroid-dependent or -resistant idiopathic nephrotic syndrome with 5.54 +/- 0.81 mg/kg/day of cyclosporin A (CsA). Pre-CsA renal biopsy (RB1) had been carried out 11.6 +/- 12.2 months prior to CsA treatment. It showed minimal glomerular changes (MCD) in 22, and 1 to 16 glomeruli with lesions of focal segmental glomerulosclerosis (FSGS) per biopsy in 14. Pretreatment serum creatinine levels were (mumol/liter) 97.6 +/- 39.4 and were higher in FSGS (117.1 +/- 48.3) than in MCD (85.2 +/- 26.9; P0.04). Repeat biopsy (RB2) was done after 19.6 +/- 15.2 months (6 to 78) of CsA treatment. At this time, in 15 patients the minimal glomerular lesions observed on RB1 were unchanged, whereas in 7 patients lesions of FSGS were now visible. In patients with FSGS on RB1 and RB2, serum creatinine at the end of CsA treatment was 130.6 +/- 60.1 mumol/liter, significantly greater (P = 0.022) than the corresponding levels in the subset with MCD (87.3 +/- 24.8). The contrast between the remarkable stability of renal function in the patients with MCD and the worsening of renal function in the subgroup with FSGS was explained in the latter by an aggravation of renal histologic lesions, with a greater number of glomeruli with FSGS, of obsolescent glomeruli, and of interstitial fibrosis/infiltrates. This aggravation of the primary renal disease was observed in some cases where CsA had obtained partial or even complete remission. Few of the tubular lesions and of vascular changes were typical of CsA toxicity but rather suggested development of the primary renal disease. In contrast, although some increase in the degree of tubulointerstitial lesions was observed on RB2, the rating of such lesions was much less severe in patients whose renal biopsy showed persistently normal glomeruli after exposure to CsA. Overall, the most severe interstitial/vascular lesions were observed in patients treated with the highest CsA dosages, and the "cut-off" of dosage safety appeared to be 5.5 mg/kg/day. Two patients died during the study period. Long-term surveillance of the extant 34 patients showed that 8, all of whom had FSGS, evolved to end-stage renal failure due to progression of their primary renal disease after ending CsA treatment. Four patients were failures of CsA and returned to conventional therapy. CsA treatment was continued for 12 to 60 months in fourteen patients who achieved remission.(ABSTRACT TRUNCATED AT 400 WORDS)

The kidney is affected in a variety of vasculitic syndrome. Vasculitis represent an heterogeneous group of inflammatory disease concerning vessels. They can be considered as secondary in systemic lupus erythematosus, cryoglobulinemia, rheumatoid polyarthritis but also in infectious diseases (Streptococci, hepatitis B) in malignant disease and after drugs. However, in many circumstances, no causes are found. The discovery of autoantibodies directed against components of neutrophil cytoplasm (ANCA) represent a great progress in the understanding of vasculitis. ANCA are autoantibodies directed against neutrophil lysosomial enzymes, preferentially myeloperoxidase and proteinase 3. They are frequently found in patients with idiopathic necrotizing vasculitis, systemic or localized to the kidney (Wegener granulomatosis, microscopic periarteritis, pauci-immune necrotizing glomerulonephritis, Churg and Strauss syndrome and polyarteritis nodosa). Diagnostic and prognostic values are sure, although their presence is unconstant with variable percentage in relation with the type of vasculitis. The increase of ANCA level is not always related with disease relapse. Conversely, a permanent low level means a quiescent disease. At the present time, it is not known if ANCA play a pathogenetic role or if they constitute a marker of the disease.

From 1987 to 1991, 2500 sera were tested for presence of anti-neutrophil cytoplasmic antibodies (ANCA) by standard indirect immunofluorescence (IIF) and specific proteinase 3 (PR3) and myeloperoxydase (MPO) ELISA. Clinical and histological data leading to precise diagnosis were retrospectively obtained in 98 patients with ANCA positivity by IIF and then a comparative study based on ANCA specificity was performed. Vasculitis was present in all cases. Among patients with anti-PR3 (n = 38), 19 had Wegener's granulomatosis (WG), 15 microscopic polyarteritis (mPA), 2 idiopathic necrotizing and crescentic glomerulonephritis (NCGN) and 2 relapsing polychondritis (RP). Among patients with anti-MPO (n = 45), 26 had mPA, 3 classical polyarteritis nodosa (PAN), 5 WG, 8 NCGN, 2 systemic lupus erythematosus (SLE) and one Churg-Strauss syndrome (CSS). Negative MPO and PR3 specific ELISA despite positive IIF were observed in 15 patients (13 WG, 1 mPA, 1 PAN). In the PR3 group, males predominated (66%) and the mean age was 49 years (range 13-85); in the MPO group, females predominated (62%) and the mean age was 57 years (range 13-85). These differences were statistically significant (p0.05). Renal involvement was present in 92% of patients and renal biopsy showed pauci-immune necrotizing and crescentic glomerulonephritis in nearly all cases. PR3 specificity was associated with frequent eye involvement (32%) and presence of granulomas (45%), but was not associated with other autoantibodies. MPO specificity was associated with a higher prevalence of pulmonary hemorrhage (40%) and various autoimmune disorders, especially antinuclear antibodies. Cholestasis was observed in 50% of WG with negative MPO and PR3 ELISA. Renal and patient survival at the 75th percentile was 15 months with MPO-ANCA and 16 months with PR3, and was similar for patients with WG and mPA. Relapses occurred in 20% of patients with anti-MPO and 36% of patients with anti-PR3. Serological follow-up was obtained in 44 patients. With immunosuppressive treatment, ANCA disappeared in 66% of cases and this disappearance was always associated with absence of disease activity.1. This study confirms that the presence of ANCA is a good marker of vasculitis. 2. Despite some clinical differences, MPO and PR3-associated vasculitis have a similar prognosis. 3. The titer of ANCA determined by ELISA is not correlated with the severity of vasculitis but disappearance of ANCA is always associated with absence of disease activity.

Clinical and histological data leading to precise diagnosis were retrospectively obtained in 98 patients with antineutrophil cytoplasmic antibodies (ANCA) detected by indirect immunofluorescence (IIF). Specificity was determined by myeloperoxidase (MPO) and proteinase 3 (PR3) specific ELISA in all and a comparative study based on ANCA specificity was performed. Vasculitis was present in all cases. PR3-ANCA occurred predominantly in males (25/38) with WG (19/38). MPO-ANCA occurred predominantly in older women and were often associated with various autoimmune disorders. There was a high prevalence of lung hemorrhage (18/45) and mPA (26/45) in this group. Patients with negative MPO and PR3 specific ELISA despite positive IIF (n = 15) were almost exclusively WG (13/15) and were characterized by a high prevalence of hepatic and digestive manifestations. Renal and patient survival at the 75th percentile was 15 months with MPO-ANCA and 16 months with PR3, and was similar for patients with WG and mPA. With immunosuppressive treatment, ANCA disappeared in 66% of cases and this disappearance was always associated with absence of disease activity.

In order to appreciate the frequency of hepatitis B virus (HBV) infection in patients with glomerular diseases in France, a low endemic country, we reviewed the series of patients biopsied in the years 1983-1989 in 2 departments of nephrology differing by the characteristics of the population. In Saint-Brieuc, where the population is almost exclusively Caucasian, with nearly no immigrant, HBsAg was not detected in any of the 86 patients. In Paris, a large number of patients come from highly or intermediately endemic regions. HBsAg was detected in 3 of 209 patients, 2 of the 75 patients with membranous nephropathy and 1 of the 32 patients with minimal-change nephrotic syndrome. These patients came from Africa and Asia. Therefore, in low endemic countries, the role of HBV infection in the etiology of glomerulonephritis is minimal. But, because of the late severity of the disease, screening remains essential in patients belonging to the high-risk groups.

The specific antigens to antineutrophil cytoplasmic antibodies (ANCA) and their relations with renal diseases begin to be well-known. In patients with systemic vasculitis, two major antigens have been recognized: proteinase 3 and myoloperoxydase. These enzymes are located in the azurophilic granules of neutrophils and migrate to the surface of these cells when they are activated. Other antigens, such as elastase, lactoferrin, CAP57 and cathepsin G, have been identified, but they are less commonly encountered. The presence of ANCA is particularly frequent in Wegener's granulomatosis, microscopic periarteritis, crescentic necrotizing glomerulonephrites without immunoglobulin deposits; it is less frequent in periarteritis nodosa and in Churg-Strauss' syndrome. ANCA can now be considered as markers of vasculitis; they are related to disease activity and can be used to evaluate the effectiveness of treatments.

Antineutrophil cytoplasmic autoantibodies have been recently reported in sera from patients with inflammatory bowel disease. We report our experience based on 90 patients with ulcerative colitis, 148 patients with Crohn's disease, and 60 controls. Determination of antineutrophil cytoplasmic autoantibodies was performed by the indirect immunofluorescence technique on ethanol fixed leucocytes. The specificities for proteinase 3, myeloperoxidase, and lactoferrin were tested by enzyme-linked immunosorbent assay. Forty-three out of 90 (48%) patients with ulcerative colitis, 10 out of 148 (7%) patients with Crohn's disease, and none of controls were positive by indirect immunofluorescence technique. All patients but two with positive immunofluorescence exhibited a perinuclear staining pattern. Among patients with ulcerative colitis, there was no relationship between the presence of perinuclear antineutrophil cytoplasmic autoantibodies and disease location or activity. Seven out of 20 (35%) patients with ulcerative colitis who had a previous colectomy (including 1 with ileoanal anastomosis) had perinuclear antineutrophil cytoplasmic autoantibodies. Antineutrophil cytoplasmic autoantibody specificity was not directed against myeloperoxidase, proteinase 3 or lactoferrin in sera from patients with inflammatory bowel diseases. Inflammatory bowel diseases are associated with a new subset of antineutrophil cytoplasmic autoantibodies. Among patients with Crohn's disease and ulcerative colitis, the sensitivity and specificity of the presence of perinuclear antineutrophil cytoplasmic autoantibodies for ulcerative colitis was 46% and 93%, respectively. Their presence reinforces the likelihood of underlying immunologic dysregulation in ulcerative colitis. Identification of the autoantigen(s) to which these antibodies are directed might facilitate the understanding of inflammatory bowel disease pathophysiology.

The incidence of beta 2-microglobulin deposits appears to increase with time on dialysis. However, the precise prevalence of the disease is not known at present because adequate, noninvasive diagnostic procedures are still lacking. We performed systematic synovial biopsies of the sternoclavicular joint during surgical parathyroidectomy in 22 chronic hemodialysis patients with severe hyperparathyroidism. Nine of the patients proved to have beta 2-microglobulin amyloid deposits as demonstrated by Congo red staining and by immunofluorescence. They had undergone dialysis for longer time periods (12.6 vs 8.5 years, p less than 0.02) and tended to be older than the 13 amyloid-negative patients. They also had a significantly higher body aluminum overload, as demonstrated by a higher increase of plasma aluminum after desferrioxamine infusion. Finally, the presence of Congo-red-positive deposits correlated well with clinical and x-ray findings suggestive of dialysis amyloidosis.

In a retrospective study of 82 adults with idiopathic membranous nephropathy, we have studied the predictive factors of renal death. Thirty one patients developed renal failure, sixteen of them progressed to end-stage renal failure (ESRF) (13 males and 3 females). Nine patients developed ESRF in the first 5 years following the renal biopsy. The males and the patients with a nephrotic syndrome have a high risk of ESRF. The age is not a predictive factor of poor outcome. Hypertension seems to be more frequent in patients who developed early but slowly progressive renal failure. Extensive renal interstitial lesions are indicative of poor renal prognosis.

Six cases of chronic renal failure related to granulomatous renal sarcoidosis are reported and compared with data in the literature. The particular features of sarcoidosis granulomatous interstitial nephritis should be emphasised because presentation may be misleading. Renal failure usually presents with a rapidly progressive course, either isolated or associated with mild proteinuria and sterile leukocyturia, while extrarenal localisations may be absent. Diagnosis should be suspected on the basis of elevated or paradoxically normal serum calcium concentrations, due to increased plasma concentrations of calcitriol, while immunoreactive circulating parathormone concentrations are depressed. Calcitriol as well as angiotensin-converting enzyme could represent unregulated secretion products from granulomatous tissue and their plasma concentrations may roughly reflect activity of the disease. Early corticosteroid treatment dramatically improves renal function but long-term renal prognosis may be oblitered due to progressive chronic renal failure related to fibrosis scarring.

Microchimerism after allogeneic organ transplantation may be a mechanism for induction of donor-specific graft acceptance. However, the frequency of chimerism and its relevance in long-term tolerance are uncertain. We studied 15 long-surviving (more than 20 years) cadaveric-kidney transplant recipients for the systemic presence of donor alleles with allele-specific genomic amplification of DRB1 and H-Y loci. Microchimerism was observed in 1 case in peripheral blood and in 4 cases in skin. Chimerism and number of HLA alleles shared by donor and recipient were not correlated. This low frequency of microchimerism in long-term kidney allograft recipients raises doubts about a major participation of chimerism in donor-specific tolerance.

Renal prognosis cannot be easily predicted in females with hereditary nephritis (HN). Thirty-six women with persistent urinary abnormalities, belonging to 24 families with progressive HN, were studied. Renal biopsy specimens were available in 23 patients and were studied by light and electron microscopy (EM). Nine women (group I) progressed to early renal failure, at 35 yrs of age or less. Five women (group II) progressed to late renal failure at 45 yrs of age or more. In contrast, 22 patients have so far normal renal function, and 14 of these (group IV) range from 31 to 62 yrs of age. Diffuse glomerular basement membrane (GBM) thickening was found by EM in 6 of 7 cases of group I, whereas it was found in no patient of group IV. The following features are suggestive of progressive nephritis in females: gross hematuria in childhood, nephrotic syndrome, and diffuse GBM thickening by EM. In contrast, family history of HN without nerve deafness, normal or nearly normal kidney on repeat biopsy, and thin or normal GBM by EM are suggestive of less or nonprogressive renal disease. Further follow-up is needed to assess the prognostic significance of these features.

Twenty-three uremic patients on intermittent hemodialysis for eight to eighteen years provided the material for the present pathological study. In all of them, there was evidence for dialysis related amyloidosis based on previous clinical or histological findings or both. The material examined consisted of nine skin biopsies, five abdominal fat aspirates, eight trans-iliac bone biopsies and numerous post-mortem specimens of various visceral organs from eight cases. None of the skin biopsies or fat aspirates showed amyloid deposits. In only one bone biopsy could a small Congo red positive area be recognized that showed characteristic birefringence under polarizing light. Autopsy material findings were negative except for one case: this patient had been dialyzed for 18 years. Very minute amyloid deposits with a positive immunofluorescence staining for beta 2-microglobulin (beta 2-M) were found in the walls of small vessels from her lung, heart, liver and intestine. Thus, in chronic hemodialysis patients the accumulation of beta 2-M amyloid fibrils in tissues other than joints and juxta-articular structures appears to have a low incidence, to occur lately and to be of limited size. Although extra-articular amyloid deposits may progressively occur and extend with increasing survival time on dialysis, tiny deposits such as those observed in only two of our patients will hardly lead to serious complications.

The authors have studied 6 cases of systemic AA amyloidosis associated with ankylosing spondylitis. Renal failure occurred in all patients a mean of 19 years after the clinical onset of the rheumatic disease. Three patients progressed rapidly (between 3 months and 3 years) to end-stage renal failure. Such an outcome did not depend upon early onset of the renal impairment, degree of inflammation or treatment with colchicine. All patients were alive 2 to 10 years later, and this confirms a better prognosis than with AL amyloidosis. The utility of combining Wright's permaganate reaction with immunological methods to characterize the amyloid deposits was also confirmed. It is concluded that amyloidosis is a rare complication of ankylosing spondylitis and probably depends on a genetic predisposition. The possibility of amyloidosis should be kept in mind when proteinuria or renal failure appear in the course of ankylosing spondylitis.

Six families including 27 patients with adult nephronophthisis were studied. The diagnosis was based on the evidence of heredofamilial chronic tubulointerstitial renal disease, not related to urologic abnormality, and progressing to renal failure in at least 2 members of each kindred. In two families, the mode of inheritance is compatible with recessive autosomal transmission; retinal heredodegeneration was found in both kindreds; mean age at end-stage renal failure (ESRF) was 22 years. In one additional case, kidney involvement is apparently sporadic, and associated with retinal changes and blindness. In one kindred, the mode of inheritance could not be determined. In the last 3 families, pedigrees are compatible with dominant autosomal transmission; retinal involvement was found in none; ESRF developed at a mean age of 47 years. Renal cysts were detected by ultrasonography in 9 of 12 patients; they were located at the cortico-medullary junction or in the medulla in 5 cases. Renal biopsy showed rather similar changes in the various kindreds. These results are compared with those already reported from 29 families with adult nephronophthisis.

Systemic lambda light-chain deposition occurred in a 73-year-old man with myeloma. An initial renal biopsy specimen showed the features of myeloma kidney. When he died 22 months later lambda light chains were detected by immunofluorescence in kidneys, liver, spleen, and heart. They were probably responsible for cardiac dysfunction and the fatal arrhythmia. It is suggested that in this patient deposition was due to a structural alteration of the light chains, possibly induced by cyclophosphamide.