Rituximab as maintenance therapy for ANCA-associated vasculitides: pooled analysis and long-term outcome of 277 patients included in the MAINRITSAN trials.

OBJECTIVE: To compare the long-term efficacy and safety of azathioprine (AZA), 18-month fixed-schedule rituximab (RTX), 18-month tailored RTX and 36-month RTX in preventing relapses in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis who achieved a complete remission after induction therapy. Patients treated with 36-month RTX received either a fixed or a tailored regimen for the first 18 months and a fixed regimen for the last 18 months (36-month fixed/fixed RTX and 36-month tailored/fixed RTX, respectively). METHODS: The Maintenance of Remission using Rituximab in Systemic ANCA-associated Vasculitis (MAINRITSAN) trials sequentially compared: 18-month fixed-schedule RTX versus AZA (MAINRITSAN); 18-month fixed-schedule RTX versus 18-month tailored-RTX (MAINRITSAN2); and extended therapy to 36 months with four additional RTX infusions after MAINRITSAN2 versus placebo (MAINRITSAN3). Patients were then followed prospectively through month 84 and their data were pooled to analyse relapses and adverse events. The primary endpoint was relapse-free survival at month 84. RESULTS: 277 patients were enrolled and divided in 5 groups: AZA (n=58), 18-month fixed-schedule RTX (n=97), 18-month tailored-RTX (n=40), 36-month tailored/fixed RTX (n=42), 36-month fixed/fixed RTX (n=41). After adjustment for prognostic factors, 18-month fixed-schedule RTX was superior to AZA in preventing major relapses at month 84 (HR 0.38, 95% CI 0.20 to 0.71). The 18-month tailored-RTX regimen was associated with an increased risk of major relapse compared with fixed-schedule regimen (HR 2.92, 95% CI 1.43 to 5.96). The risk of major relapse was similar between 36-month fixed/fixed and 18-month fixed-RTX (HR 0.69, 95% CI 0.38 to 1.25). CONCLUSIONS: According to these results, it appears that the 84-month remission rate is higher with an 18-month fixed RTX regimen compared with AZA and 18-month tailored RTX. Also, extending RTX to 36 months does not appear to reduce the long-term relapse rate compared with the 18-month fixed RTX regimen. However, as this study was underpowered to make this comparison, further prospective studies are needed to determine the potential long-term benefits of extending treatment in these patients.

Weaning of maintenance immunosuppressive therapy in lupus nephritis (WIN-Lupus): results of a multicentre randomised controlled trial.

OBJECTIVES: Lupus nephritis (LN) is a frequent complication of systemic lupus erythematosus (SLE). Severe (proliferative) forms of LN are treated with induction immunosuppressive therapy (IST), followed by maintenance IST, to target remission and avoid relapses. The optimal duration of maintenance IST is unknown. The WIN-Lupus trial tested whether IST discontinuation after 2‒3 years was non-inferior to IST continuation for two more years in proliferative LN. METHODS: WIN-Lupus was an investigator-initiated multicentre randomised controlled trial. Patients receiving maintenance IST with azathioprine or mycophenolate mofetil for 2-3 years, and hydroxychloroquine, were randomised (1:1) into two groups: (1) IST continuation and (2) IST discontinuation. The primary endpoint was the relapse rate of proliferative LN at 24 months. Main secondary endpoints were the rate of severe SLE flares, survival without renal relapse or severe flare, adverse events. RESULTS: Between 2011 and 2016, 96 patients (out of 200 planned) were randomised in WIN-Lupus: IST continuation group (n=48), IST discontinuation group (n=48). Relapse of proliferative LN occurred in 5/40 (12.5%) patients with IST continuation and in 12/44 (27.3%) patients with IST discontinuation (difference 14.8% (95% CI -1.9 to 31.5)). Non-inferiority was not demonstrated for relapse rate; time to relapse did not differ between the groups. Severe SLE flares (renal or extrarenal) were less frequent in patients with IST continuation (5/40 vs 14/44 patients; p=0.035). Adverse events did not differ between the groups. CONCLUSIONS: Non-inferiority of maintenance IST discontinuation after 2‒3 years was not demonstrated for renal relapse. IST discontinuation was associated with a higher risk of severe SLE flares. TRIAL REGISTRATION NUMBER: NCT01284725.

Kidney Histopathology Can Predict Kidney Function in ANCA-Associated Vasculitides with Acute Kidney Injury Treated with Plasma Exchanges.

BACKGROUND: Data from the PEXIVAS trial challenged the role of plasma exchange (PLEX) in ANCA-associated vasculitides (AAV). We aimed to describe kidney biopsy from patients with AAV treated with PLEX, evaluate whether histopathologic findings could predict kidney function, and identify which patients would most benefit from PLEX. METHODS: We performed a multicenter, retrospective study on 188 patients with AAV and AKI treated with PLEX and 237 not treated with PLEX. The primary outcome was mortality or KRT at 12 months (M12). RESULTS: No significant benefit of PLEX for the primary outcome was found. To identify patients benefitting from PLEX, we developed a model predicting the average treatment effect of PLEX for an individual depending on covariables. Using the prediction model, 223 patients had a better predicted outcome with PLEX than without PLEX, and 177 of them had >5% increased predicted probability with PLEX compared with without PLEX of being alive and free from KRT at M12, which defined the PLEX-recommended group. Risk difference for death or KRT at M12 was significantly lower with PLEX in the PLEX-recommended group (-15.9%; 95% CI, -29.4 to -2.5) compared with the PLEX not recommended group (-4.8%; 95% CI, 14.9 to 5.3). Microscopic polyangiitis, MPO-ANCA, higher serum creatinine, crescentic and sclerotic classes, and higher Brix score were more frequent in the PLEX-recommended group. An easy to use score identified patients who would benefit from PLEX. The average treatment effect of PLEX for those with recommended treatment corresponded to an absolute risk reduction for death or KRT at M12 of 24.6%. CONCLUSIONS: PLEX was not associated with a better primary outcome in the whole study population, but we identified a subset of patients who could benefit from PLEX. However, these findings must be validated before utilized in clinical decision making.

Kidney biopsy in very elderly patients: indications, therapeutic impact and complications.

BACKGROUND: Few data is available on the risk/benefit balance of native kidney biopsy (KB) in very elderly patients. METHODS: Multicenter retrospective cohort study in the Aix-Marseille area: the results of KB and medical charts of all patients over 85 years biopsied between January 2010 and December 2018 were reviewed. RESULTS: 104 patients were included. Median age was 87 years. Indications for KB were: acute kidney injury (AKI) in 69.2% of patients, nephrotic syndrome (NS) with AKI in 13.5%, NS without AKI in 12.5%, and proteinuria in 4.8%. Median serum creatinine was 262 µmol/L, 21% of patients required dialysis at the time of KB. Significant bleeding occurred in 7 (6.7%) patients, requiring blood cell transfusion in 4 (3.8%), and radiological embolization in 1 (1%). The most frequent pathological diagnoses were: non-diabetic glomerular diseases (29.8%, including pauci-immune crescentic glomerulonephritis in 9.6%), hypertensive nephropathy (27.9%), acute interstitial nephritis (16.3%), renal involvement of hematological malignancy (8.7%), and acute tubular necrosis (6.7%). After KB, 51 (49%) patients received a specific treatment: corticosteroids (41.3%), cyclophosphamide (6.7%), rituximab (6.7%), bortezomib (3.8%), other chemotherapies (3.8%). Median overall survival was 31 months. CONCLUSIONS: KB can reveal a diagnosis with therapeutic impact even in very elderly patients. Severe bleeding was not frequent in this cohort, but KB may have not been performed in more vulnerable patients.

Randomized Trial Comparing Double Versus Triple Bortezomib-Based Regimen in Patients With Multiple Myeloma and Acute Kidney Injury Due to Cast Nephropathy.

PURPOSE: We report a multicenter controlled trial comparing renal recovery and tolerance profile of doublet versus triplet bortezomib-based regimens in patients with initial myeloma cast nephropathy (CN) and acute kidney injury (AKI) without need for dialysis. METHODS: After symptomatic measures and high-dose dexamethasone, patients were randomly assigned to receive bortezomib plus dexamethasone (BD), or BD plus cyclophosphamide (C-BD). In patients with < 50% reduction of serum free light chains (sFLCs) after 3 cycles, chemotherapy was reinforced with either cyclophosphamide (BD group) or thalidomide (C-BD group). RESULTS: Ninety-two patients were enrolled in each group. At random assignment, characteristics of the 2 groups were similar, including median age (68 years) and serum creatinine level (305.5 and 273.5 µmol/L in BD and C-BD group, respectively). At 3 months, renal response rate (primary end point) was not different (41 v 47 responders in the BD and C-BD groups, respectively; relative risk [RR], 0.87; P = .46). Very good partial response (free light chain reduction ≥ 90%) or more was achieved in 36 and 47 patients, respectively (RR, 0.76; P = .10). After 1 cycle of chemotherapy, 69 in the BD group and 67 patients in the C-BD group had achieved sFLC level ≤ 500 mg/L. Serious adverse events were recorded in 30 and 40 patients, respectively. At 12 months, 19 patients had died (9 in the BD group v 10 in the C-BD group), including 10 (6 in the BD group and 4 in the C-BD group) from myeloma progression and 3 (0 in the BD group and 3 in the C-BD group) from infection. Within median follow-up of 27 months, 43 and 42 patients switched to new therapy, respectively. Overall, 50 patients (24 in the BD group and 26 in the C-BD group) had died. CONCLUSION: This randomized study did not show any benefit of C-BD compared with BD on renal recovery of patients with initial CN not requiring dialysis. Adding cyclophosphamide did not sufficiently improve the efficacy-toxicity balance. Patients with myeloma with AKI are fragile, and indication for doublet or triplet regimen should be adapted to frailty.

Long-Term Rituximab Use to Maintain Remission of Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Randomized Trial.

BACKGROUND: Biannual rituximab infusions over 18 months effectively maintain remission after a "standard" remission induction regimen for patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). OBJECTIVE: To evaluate the efficacy of prolonged rituximab therapy in preventing AAV relapses in patients with granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) who have achieved complete remission after completing an 18-month maintenance regimen. DESIGN: Randomized controlled trial. (ClinicalTrials.gov: NCT02433522). SETTING: 39 clinical centers in France. PATIENTS: 68 patients with GPA and 29 with MPA who achieved complete remission after the first phase of maintenance therapy. INTERVENTION: Rituximab or placebo infusion every 6 months for 18 months (4 infusions). MEASUREMENTS: The primary end point was relapse-free survival at month 28. Relapse was defined as new or reappearing symptoms or worsening disease, with a Birmingham Vasculitis Activity Score greater than 0. RESULTS: From March 2015 to April 2016, 97 patients (mean age, 63.9 years; 35% women) were randomly assigned, 50 to the rituximab and 47 to the placebo group. Relapse-free survival estimates at month 28 were 96% (95% CI, 91% to 100%) and 74% (CI, 63% to 88%) in the rituximab and placebo groups, respectively, an absolute difference of 22% (CI, 9% to 36%) with a hazard ratio of 7.5 (CI, 1.67 to 33.7) (P = 0.008). Major relapse-free survival estimates at month 28 were 100% (CI, 93% to 100%) versus 87% (CI, 78% to 97%) (P = 0.009), respectively. At least 1 serious adverse event developed in 12 patients (24%) in the rituximab group (with 9 infectious serious adverse events occurring among 6 patients [12%]) versus 14 patients (30%) in the placebo group (with 6 infectious serious adverse events developing among 4 patients [9%]). No deaths occurred in either group. LIMITATION: Potential selection bias based on previous rituximab response and tolerance. CONCLUSION: Extended therapy with biannual rituximab infusions over 18 months was associated with a lower incidence of AAV relapse compared with standard maintenance therapy. PRIMARY FUNDING SOURCE: French Ministry of Health and Hoffmann-La Roche.

Reducing the initial number of rituximab maintenance-therapy infusions for ANCA-associated vasculitides: randomized-trial post-hoc analysis.

OBJECTIVE: The randomized, controlled MAINRITSAN2 trial was designed to compare the capacity of an individually tailored therapy [randomization day 0 (D0)], with reinfusion only when CD19+ lymphocytes or ANCA had reappeared, or if the latter's titre rose markedly, with that of five fixed-schedule 500-mg rituximab infusions [D0 + D14, then months (M) 6, 12 and 18] to maintain ANCA-associated vasculitis (AAV) remissions. Relapse rates did not differ at M28. This ancillary study was undertaken to evaluate the effect of omitting the D14 rituximab infusion on AAV relapse rates at M12. METHODS: MAINRITSAN2 trial data were subjected to post-hoc analyses of M3, M6, M9 and M12 relapse-free survival rates in each arm as primary end points. Exploratory subgroup analyses were run according to CYC or rituximab induction and newly diagnosed or relapsing AAV. RESULTS: At M3, M6, M9 and M12, respectively, among the 161 patients included, 79/80 (98.8%), 76/80 (95%), 74/80 (92.5%) and 73/80 (91.3%) from D0, and 80/81 (98.8%), 78/81 (96.3%), 76/81 (93.8%) and 76/81 (93.8%) from D0+D14 groups were alive and relapse-free. No between-group differences were observed. Results were not affected by CYC or rituximab induction, or newly diagnosed or relapsing AAV. CONCLUSIONS: We were not able to detect a difference between the relapse-free survival rates for up to M12 for the D0 and D0+D14 rituximab-infusion groups, which could suggest that omitting the D14 rituximab remission-maintenance dose did not modify the short-term relapse-free rate. Nevertheless, results at M12 may also have been influenced by the rituximab-infusion strategies for both groups.

Long-term efficacy of remission-maintenance regimens for ANCA-associated vasculitides.

OBJECTIVE: To compare long-term efficacy of remission-maintenance regimens in patients with newly diagnosed or relapsing antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitides. METHODS: The 28-month Maintenance of Remission using Rituximab in Systemic ANCA-associated Vasculitis trial compared rituximab with azathioprine to maintain remission in patients with newly diagnosed or relapsing granulomatosis with polyangiitis, microscopic polyangiitis or renal-limited ANCA-associated vasculitis. Thereafter, prospective patient follow-up lasted until month 60. The primary endpoint was the major-relapse rate at month 60. Relapse and serious adverse event-free survival were also assessed. RESULTS: Among the 115 enrolled patients, only one was lost to follow-up at month 60. For the azathioprine and rituximab groups, respectively, at month 60, the major relapse-free survival rates were 49.4% (95% CI 38.0% to 64.3%) and 71.9% (95% CI 61.2% to 84.6%) (p=0.003); minor and major relapse-free survival rates were 37.2% (95% CI 26.5% to 52.2%) and 57.9% (95% CI 46.4% to 72.2%) (p=0.012); overall survival rates were 93.0% (95% CI 86.7% to 99.9%) and 100% (p=0.045) and cumulative glucocorticoid use was comparable. Quality-adjusted time without symptoms and toxicity analysis showed that rituximab-treated patients had 12.6 months more without relapse or toxicity than those given azathioprine (p<0.001). Antiproteinase-3-ANCA positivity and azathioprine arm were independently associated with higher risk of relapse. HRs of positive ANCA to predict relapse increased over time. CONCLUSION: The rate of sustained remission for ANCA-associated vasculitis patients, following rituximab-based or azathioprine-based maintenance regimens, remained superior over 60 months with rituximab, with better overall survival. TRIAL REGISTRATION NUMBER: NCT00748644.

Comparison of individually tailored versus fixed-schedule rituximab regimen to maintain ANCA-associated vasculitis remission: results of a multicentre, randomised controlled, phase III trial (MAINRITSAN2).

OBJECTIVE: To compare individually tailored, based on trimestrial biological parameter monitoring, to fixed-schedule rituximab reinfusion for remission maintenance of antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAVs). METHODS: Patients with newly diagnosed or relapsing granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) in complete remission after induction therapy were included in an open-label, multicentre, randomised controlled trial. All tailored-arm patients received a 500 mg rituximab infusion at randomisation, with rituximab reinfusion only when CD19+B lymphocytes or ANCA had reappeared or ANCA titre rose markedly based on trimestrial testing until month 18. Controls received a fixed 500 mg rituximab infusion on days 0 and 14 postrandomisation, then 6, 12 and 18 months after the first infusion. The primary endpoint was the number of relapses (new or reappearing symptom(s) or worsening disease with Birmingham Vasculitis Activity Score (BVAS)>0) at month 28 evaluated by an independent Adjudication Committee blinded to treatment group. RESULTS: Among the 162 patients (mean age: 60 years; 42% women) included, 117 (72.2%) had GPA and 45 (27.8%) had MPA. Preinclusion induction therapy included cyclophosphamide for 100 (61.7%), rituximab for 61 (37.6%) and methotrexate for 1 (0.6%). At month 28, 21 patients had suffered 22 relapses: 14/81 (17.3%) in 13 tailored-infusion recipients and 8/81 (9.9%) in 8 fixed-schedule patients (p=0.22). The tailored-infusion versus fixed-schedule group, respectively, received 248 vs 381 infusions, with medians (IQR) of 3 (2-4) vs 5 (5-5) administrations. CONCLUSION: AAV relapse rates did not differ significantly between individually tailored and fixed-schedule rituximab regimens. Individually tailored-arm patients received fewer rituximab infusions. TRIAL REGISTRATION NUMBER: NCT01731561; Results.

Predictive features of chronic kidney disease in atypical haemolytic uremic syndrome.

Chronic kidney disease (CKD) is a frequent and serious complication of atypical haemolytic uremic syndrome (aHUS). We aimed to develop a simple accurate model to predict the risk of renal dysfunction in aHUS based on clinical and biological features available at hospital admission. Renal function at 1-year follow-up, based on an estimated glomerular filtration rate < 60mL/min/1.73m2 as assessed by the Modification of Diet in Renal Disease equation, was used as an indicator of significant CKD. Prospectively collected data from a cohort of 156 aHUS patients who did not receive eculizumab were used to identify predictors of CKD. Covariates associated with renal impairment were identified by multivariate analysis. The model performance was assessed and a scoring system for clinical practice was constructed from the regression coefficient. Multivariate analyses identified three predictors of CKD: a high serum creatinine level, a high mean arterial pressure and a mildly decreased platelet count. The prognostic model had a good discriminative ability (area under the curve = .84). The scoring system ranged from 0 to 5, with corresponding risks of CKD ranging from 18% to 100%. This model accurately predicts development of 1-year CKD in patients with aHUS using clinical and biological features available on admission. After further validation, this model may assist in clinical decision making.

Rituximab versus azathioprine for ANCA-associated vasculitis maintenance therapy: impact on global disability and health-related quality of life.

OBJECTIVES: To investigate the effects on health-related quality of life (HRQOL) and functional capability of rituximab vs azathioprine for ANCA-associated vasculitis (AAV) maintenance therapy. METHODS: In a 24-month phase III randomised-controlled trial, 115 patients over time received rituximab or azathioprine for AAV maintenance therapy. Mean changes of 36-item Short-form Health Survey (SF-36) and Health Assessment Questionnaire (HAQ) scores from baseline were analysed. RESULTS: Mean improvements of HAQ scores, from baseline to month 24 were significantly better for the rituximab (0.16 points lower) than the azathioprine group (p=0.038). As demonstrated by SF-36, study patients' baseline HRQOL was significantly impaired compared with age- and sex-matched US norms. At month 24, mean changes from baseline of SF-36 physical component score tended to be better for the rituximab group (+3.95 points, p=0.067) whereas mean changes from baseline of the SF-36 mental component score were significantly better for the azathioprine group (+4.23 points, p=0.041). CONCLUSIONS: Azathioprine-treated patients' for AAV maintenance therapy showed a decline in physical abilities when compared to RTX at M24 in the MAINRITSAN trial. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov/, NCT00748644.

Plasma exchanges for the treatment of severe systemic necrotizing vasculitides in clinical daily practice: Data from the French Vasculitis Study Group.

The use of plasma exchanges (PLEX) in systemic necrotizing vasculitides (SNV) still need to be codified. To describe indications, efficacy and safety of PLEX for the treatment of SNV, we conducted a multicenter retrospective study on patients with ANCA-associated vasculitis (AAV) or non-viral polyarteritis nodosa (PAN) treated with PLEX. One hundred and fifty-two patients were included: GPA (n = 87), MPA (n = 56), EGPA (n = 4) and PAN (n = 5). PLEX were used for rapidly progressive glomerulonephritis (RPGN) in 126 cases (86%), alveolar hemorrhage in 64 cases (42%), and severe mononeuritis multiplex in 23 cases (15%). In patients with RPGN, there was a significant improvement in renal function compared to baseline value (P < 0.0001), the plateau being reached at month 3 after PLEX initiation, and estimated glomerular filtration rate improved especially as the number of PLEX increased. In patients with alveolar hemorrhage, mechanical ventilation was discontinued in all patients after a median time of 15 days. Patients treated for mononeuritis multiplex showed improvement of severe motor weakness. After a median follow of 22 months, 18 deaths (12%) were recorded, mainly in patients with RPGN and within the first 6 months. Incidence of end-stage renal disease and/or death was similar between groups of different baseline renal function, but was increased in MPO-ANCA compared to PR3-ANCA. Adverse events attributable to PLEX were recorded in 63%. No death occurred during PLEX. This large series describes indications, efficacy and safety of PLEX in daily practice. Randomized controlled studies are ongoing to define optimal indications, PLEX regimen and concomitant medications.

Rituximab versus azathioprine for maintenance in ANCA-associated vasculitis.

BACKGROUND: The combination of cyclophosphamide and glucocorticoids leads to remission in most patients with antineutrophil cytoplasm antibody (ANCA)-associated vasculitides. However, even when patients receive maintenance treatment with azathioprine or methotrexate, the relapse rate remains high. Rituximab may help to maintain remission. METHODS: Patients with newly diagnosed or relapsing granulomatosis with polyangiitis, microscopic polyangiitis, or renal-limited ANCA-associated vasculitis in complete remission after a cyclophosphamide-glucocorticoid regimen were randomly assigned to receive either 500 mg of rituximab on days 0 and 14 and at months 6, 12, and 18 after study entry or daily azathioprine until month 22. The primary end point at month 28 was the rate of major relapse (the reappearance of disease activity or worsening, with a Birmingham Vasculitis Activity Score >0, and involvement of one or more major organs, disease-related life-threatening events, or both). RESULTS: The 115 enrolled patients (87 with granulomatosis with polyangiitis, 23 with microscopic polyangiitis, and 5 with renal-limited ANCA-associated vasculitis) received azathioprine (58 patients) or rituximab (57 patients). At month 28, major relapse had occurred in 17 patients in the azathioprine group (29%) and in 3 patients in the rituximab group (5%) (hazard ratio for relapse, 6.61; 95% confidence interval, 1.56 to 27.96; P=0.002). The frequencies of severe adverse events were similar in the two groups. Twenty-five patients in each group (P=0.92) had severe adverse events; there were 44 events in the azathioprine group and 45 in the rituximab group. Eight patients in the azathioprine group and 11 in the rituximab group had severe infections, and cancer developed in 2 patients in the azathioprine group and 1 in the rituximab group. Two patients in the azathioprine group died (1 from sepsis and 1 from pancreatic cancer). CONCLUSIONS: More patients with ANCA-associated vasculitides had sustained remission at month 28 with rituximab than with azathioprine. (Funded by the French Ministry of Health; MAINRITSAN ClinicalTrials.gov number, NCT00748644; EudraCT number, 2008-002846-51.).

Rituximab: Recommendations of the French Vasculitis Study Group (FVSG) for induction and maintenance treatments of adult, antineutrophil cytoplasm antibody-associated necrotizing vasculitides.

Increasing rituximab prescription for ANCA-associated necrotizing vasculitides justifies the publication of recommendations for clinicians. Rituximab is approved in the United States to induce and maintain remission. In Europe, rituximab was recently approved for remission induction. However, governmental agencies' approvals cannot replace clinical practice guidelines. Herein, the French Vasculitis Study Group Recommendations Committee, comprised of physicians with extensive experience in the treatment of vasculitides, presents its consensus guidelines based on literature analysis, the results of prospective therapeutic trials and personal experience.

Comparative safety and efficiency of five percutaneous kidney biopsy approaches of native kidneys: a multicenter study.

BACKGROUND: Renal biopsy (RB) is necessary for the diagnosis, prognosis, and therapy guidance of native kidney diseases. Few studies have compared outcomes of RB procedures. We retrospectively compared the safety and efficiency of five biopsy procedures. METHODS: The number of glomeruli on light microscopy (LM) and on immunofluorescence (IF) and serious adverse events following RB performed in five nephrology units (C1-C5) were collected. C1 performed ultrasound (US) assessment before RB and used a 14-gauge core-cutting needle biopsy gun, C2 US guidance and a 14-gauge needle, C3 tomodensitometry guidance and a 14-gauge needle, C4 US guidance and a 16-gauge needle, and C5 tomodensitometry guidance and a 16-gauge needle. RESULTS: RB was performed in 943 adults between January 2006 and July 2010. Serious adverse events occurred in 1.5% of biopsies. The complication rate was not different between nephrology units. The mean number of glomeruli on biopsy was 14.2 ± 8.6 with LM and 4.4 ± 3.3 on IF. It was different according to the nephrology unit for LM (p = 0.01) and for IF (p < 0.001). The number of failed biopsies was influenced by the nephrology unit and radiological guidance technique, favoring real-time US guidance. Failed biopsies using US or tomodensitometry assessment before RB was certainly due to kidney imprecise localization since it was often non-renal tissue sampling. At least 10 glomeruli were found in 69% of biopsies on LM. This rate varied according to the nephrology unit (p = 0.004) and was higher when 14-gauge needles were used in comparison with 16-gauge needles. CONCLUSION: RB is safe regardless of the technical procedure, but radiological guidance and needle size influence the efficiency of biopsies.

Left main coronary artery thrombosis complicating an idiopathic retroperitoneal fibrosis in a 37-year-old man with long-standing type I diabetes mellitus.

Retroperitoneal fibrosis is an uncommon collagen vascular disease of unknown etiology, characterized by the replacement of normal retroperitoneal tissue with fibrosis and/or chronic inflammation usually surrounding the abdominal aorta and the iliac arteries and extending into adjacent anatomic structures. No cases of acute coronary syndrome in the setting of retroperitoneal disorder have been published as yet. We report a 37-year-old man with a 14-year history of type I diabetes mellitus who was admitted to the endocrinology department for a routine check up and glycemic re-equilibration and who was later diagnosed to have an idiopathic retroperitoneal fibrosis. The patient presented during his hospitalisation with a non ST elevation myocardial infarction caused by an isolated thrombus located inside the left main coronary artery successfully treated with manual thrombectomy.