Idiopathic nephrotic syndrome relapse following SARS-CoV-2 vaccination: a series of 25 cases

Background

Several cases of idiopathic nephrotic syndrome (INS) relapse following the administration of coronavirus disease 2019 (COVID-19) vaccines have recently been reported, raising questions about the potential relationship between the immune response to COVID-19 vaccination and INS pathogenesis.

Methods

We performed a retrospective multicentre survey describing the clinical and biological characteristics of patients presenting a relapse of INS after COVID-19 vaccination, with an assessment of outcome under treatment.

Results

We identified 25 patients (16 men and 9 women) presenting a relapse within 1 month of a COVID-19 vaccine injection. The glomerular disease was of childhood onset in half of the patients and most patients (21/25) had received at least one immunosuppressive drug in addition to steroids for frequently relapsing or steroid-dependent nephrotic syndrome (NS). All patients were in a stable condition at the time of injection and 11 had no specific treatment. In five patients, the last relapse was reported >5 years before vaccine injection. The Pfizer-BioNTech (BNT162b2) vaccine was used in 80% of the patients. In 18 cases, INS relapse occurred after the first injection, a mean of 17.5 days after vaccination. A second injection was nevertheless administered in 14 of these patients. Five relapses occurred after administration of the second dose and two relapses after the administration of the third dose. All but one of the patients received steroids as first-line treatment, with an additional immunosuppressive agent in nine cases. During follow-up, complete remission was achieved in 21 patients, within 1 month in 17 cases. Only one patient had not achieved at least partial remission after 3 months of follow-up.

Conclusions

This case series suggests that, in rare patients, COVID-19 vaccination may trigger INS relapse that is generally easy to control. These findings should encourage physicians to persuade their patients to complete the COVID-19 vaccination schedule.

Can empathy be taught? A cross-sectional survey assessing training to deliver the diagnosis of end stage renal disease

Background

Receiving the diagnosis of kidney failure has a major impact on patients. Yet, the way in which this diagnosis should be delivered is not formally taught within our medical curriculum. To fill this gap we set up a training course of kidney failure diagnosis delivery for nephrology trainees since 2016. This study assessed the effectiveness of this educational intervention.

Methods

The primary outcome was change in the empathy score immediately after the training session and several months afterward, based on the Jefferson Scale of Physician Empathy (JSPE). Self-reported change in clinical practice was also evaluated. As control groups, we assessed empathy levels in untrained nephrology trainees (n = 26) and senior nephrologists (n = 71). Later on (>6 months) we evaluated participants’ perception of changes in their clinical practice due to the training.

Results

Six training sessions permitted to train 46 trainees. Most respondents (76%) considered the training to have a durable effect on their clinical practice. Average empathy scores were not significantly different in pre-trained trainees (average JSPE: 103.7 ± 11.4), untrained trainees (102.8 ± 16.4; P = 0.81) and senior nephrologists (107.2 ± 13.6; P = 0.15). Participants’ empathy score significantly improved after the training session (112.8 ± 13.9; P = 0.003). This improvement was sustained several months afterwards (average JSPE 110.5 ± 10.8; P = 0.04).

Conclusion

A single 4-hour training session can have long lasting impact on empathy and clinical practice of participants. Willingness to listen, empathy and kindness are thought to be innate and instinctive skills, but they can be acquired and should be taught.

Renal involvement in eosinophilic granulomatosis with polyangiitis (EGPA): a multicentric retrospective study of 63 biopsy-proven cases

OBJECTIVE

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic small-vessel vasculitis characterized by asthma, hypereosinophilia and ANCA positivity in 40% of patients. Renal involvement is rare and poorly described, leading to this renal biopsy-proven based study in a large EGPA cohort.

METHODS

We conducted a retrospective multicentre study including patients fulfilling the 1990 ACR criteria and/or the 2012 revised Chapel Hill Consensus Conference criteria for EGPA and/or the modified criteria of the MIRRA trial, with biopsy-proven nephropathy.

RESULTS

Sixty-three patients [27 women, median age 60 years (18-83)] were included. Renal disease was present at vasculitis diagnosis in 54 patients (86%). ANCA were positive in 53 cases (84%) with anti-MPO specificity in 44 (83%). All patients had late-onset asthma. Peripheral neuropathy was present in 29 cases (46%), alveolar haemorrhage in 10 (16%). The most common renal presentation was acute renal failure (75%). Renal biopsy revealed pauci-immune necrotizing GN in 49 cases (78%). Membranous nephropathy (10%) and membranoproliferative GN (3%) were mostly observed in ANCA-negative patients. Pure acute interstitial nephritis was found in six cases (10%); important interstitial inflammation was observed in 28 (44%). All patients received steroids with adjunctive immunosuppression in 54 cases (86%). After a median follow-up of 51 months (1-296), 58 patients (92%) were alive, nine (14%) were on chronic dialysis and two (3%) had undergone kidney transplantation.

CONCLUSION

Necrotizing pauci-immune GN is the most common renal presentation in ANCA-positive EGPA. ANCA-negative patients had frequent atypical renal presentation with other glomerulopathies such as membranous nephropathy. An important eosinophilic interstitial infiltration was observed in almost 50% of cases.

The spectrum of kidney biopsies in hospitalized patients with COVID-19, acute kidney injury, and/or proteinuria

We report a multicentric retrospective case series of patients with COVID-19 who developed acute kidney injury and/or proteinuria and underwent a kidney biopsy in the Paris and its metropolitan area. Forty-seven patients (80.9% men) with COVID-19 who underwent a kidney biopsy between March 08 and May 19, 2020 were included. Median age was 63 years IQR [52-69]. Comorbidities included hypertension (66.0%), diabetes mellitus (27.7%), obesity (27.7%), history of chronic kidney (25.5%), cardiac (38.6%) and respiratory (27.3%) diseases. Initial symptoms were fever (85.1%), cough (63.8%), shortness of breath (55.3%), and diarrhea (23.4%). Almost all patients developed acute kidney injury (97.9%) and 63.8% required renal replacement therapy. Kidney biopsy showed two main histopathological patterns, including acute tubular injury in 20 (42.6%) patients, and glomerular injury consisting of collapsing glomerulopathy and focal segmental glomerulosclerosis in 17 (36.2%) patients. Two (4.3%) patients had acute vascular nephropathy, while eight (17%) had alternative diagnosis most likely unrelated to COVID-19. Acute tubular injury occurred almost invariably in the setting of severe forms of COVID-19, whereas patients with glomerular injury had various profiles of COVID-19 severity and collapsing glomerulopathy was only observed in patients harboring a combination of APOL1 risk variants. At last follow-up, 16 of the 30 patients who initially required dialysis were still on dialysis, and 9 died. The present study describes the spectrum of kidney lesions in patients with COVID-19. While acute tubular injury is correlated with COVID-19 severity, the pattern of glomerular injury is intimately associated with the expression of APOL1 risk variants.

Malaria, Collapsing Glomerulopathy, and Focal and Segmental Glomerulosclerosis

BACKGROUND AND OBJECTIVES

Malaria, a potentially life-threatening disease, is the most prevalent endemic infectious disease worldwide. In the modern era, the spectrum of glomerular involvement observed in patients after malarial infections remains poorly described.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We therefore performed a retrospective multicenter study to assess the clinical, biologic, pathologic, and therapeutic characteristics of patients with glomerular disease demonstrated by kidney biopsy in France within 3 months of an acute malaria episode.

RESULTS

We identified 23 patients (12 men), all but 1 of African ancestry and including 10 patients with concomitant HIV infection. All of the imported cases were in French citizens living in France who had recently traveled back to France from an endemic area and developed malaria after their return to France. Eleven patients had to be admitted to an intensive care unit at presentation. Plasmodium falciparum was detected in 22 patients, and Plasmodium malariae was detected in 1 patient. Kidney biopsy was performed after the successful treatment of malaria, a mean of 24 days after initial presentation. At this time, all patients displayed AKI, requiring KRT in 12 patients. Nephrotic syndrome was diagnosed in 17 patients. Pathologic findings included FSGS in 21 patients and minimal change nephrotic syndrome in 2 patients. Among patients with FSGS, 18 had collapsing glomerulopathy (including 9 patients with HIV-associated nephropathy). In four patients, immunohistochemistry with an antibody targeting P. falciparum histidine-rich protein-2 demonstrated the presence of the malaria antigen in tubular cells but not in podocytes or parietal epithelial cells. An analysis of the apoL1 risk genotype showed that high-risk variants were present in all seven patients tested. After a mean follow-up of 23 months, eight patients required KRT (kidney transplantation in two patients), and mean eGFR for the other patients was 51 ml/min per 1.73 m².

CONCLUSIONS

In patients of African ancestry, imported Plasmodium infection may be a new causal factor for secondary FSGS, particularly for collapsing glomerulopathy variants in an APOL1 high-risk variant background.

Regional Professionals Network to Support the Renal Epidemiology and Information Registry in Ile-de-France

We present the regional professional network to support the Renal Epidemiology Information Network (REIN) registry in maintaining high quality data production and information analyses in Ile-De-France region. The network is based on a long term partnership between the nephrologists and a regional methodology support unit. It integrates clinical research assistants for data quality control. We also present organizational methods on maintaining the registry and enhancing information analyses and automating analyses reports.

Prognostic Factors in Anti-glomerular Basement Membrane Disease: A Multicenter Study of 119 Patients

We report the overall and renal outcome in a French nationwide multicenter cohort of 119 patients with anti-glomerular basement membrane (anti-GBM) disease. Sixty-four patients (54%) had an exclusive renal involvement, 7 (6%) an isolated alveolar hemorrhage and 48 (40%) a combined renal and pulmonary involvement. Initial renal replacement therapy (RRT) was required in 78% of patients; 82% received plasmapheresis, 82% cyclophosphamide, and 9% rituximab. ANCA positive (28%) patients were older (70 vs. 47 years, p < 0.0001), less frequently smokers (26 vs. 54%, p = 0.03), and had less pulmonary involvement than ANCA- patients. The 5 years overall survival was 92%. Risk factors of death (n = 11, 9.2%) were age at onset [HR 4.10 per decade (1.89-8.88) p = 0.003], hypertension [HR 19.9 (2.52-157 0.2) p = 0.005], dyslipidemia [HR 11.1 (2.72-45) p = 0.0008], and need for mechanical ventilation [HR 5.20 (1.02-26.4) p = 0.047]. The use of plasmapheresis was associated with better survival [HR 0.29 (0.08-0.98) p = 0.046]. At 3 months, 55 (46%) patients had end-stage renal disease (ESRD) vs. 37 (31%) ESRD-free and 27 (23%) unevaluable with follow-up < 3 months. ESRD patients were older, more frequently female and had a higher serum creatinine level at presentation than those without ESRD. ESRD-free survival was evaluated in patients alive without ESRD at 3 months (n = 37) using a landmark approach. In conclusion, this large French nationwide study identifies prognosis factors of renal and overall survival in anti-GBM patients.

[Retroperitoneal fibrosis in adults: Main characteristics and relevance of the diagnostic procedures based on a retrospective multicenter study on 77 cases]

INTRODUCTION

Retroperitoneal fibrosis (RPF) is a rare disorder characterized by the sheathing of retroperitoneal structures by fibro-inflammatory process. It can be either isolated or associated with an underlying disease or condition. In the absence of consistent and consensual approach, the objective of this study was to assess the relevance of diagnostic tests performed during the diagnostic work-up of RPF.

METHODS

Seventy-seven patients were included in this retrospective multicenter study. The diagnosis of RPF was defined by the presence of a thickened circumferential homogeneous tissue unsheathing the infrarenal aorta, excluding peri-aneurysmal fibrosis and a clear evidence of a cancer.

RESULTS

In 62 cases (80.5%), the RPF was considered as being primary or "idiopathic". Surgical (n=31) or CT-guided (n=9) biopsies of the RPF were performed in half of the patients showing some fibrotic or non-specific inflammatory lesions in 98% of cases. A bone marrow biopsy was performed in 23 patients leading to diagnosis of low grade B cell non-Hodgkin lymphoma in a single patient who also had a monoclonal gammopathy IgM. The systematic search for autoantibodies or serum tumor markers was of no diagnostic value.

CONCLUSIONS

Although the diagnostic procedure was heterogeneous, no cause or associated disease was found in the majority of cases of FRP in this series. In the absence of any clinical or paraclinical evidence suggesting an underlying disease or any atypical features at presentation, a number of non-invasive tests (autoantibodies, tumor markers, bone scintigraphy) and also more invasive diagnostic tests (bone marrow and RPF biopsies) seem of little relevance.

[Idiopathic retroperitoneal fibrosis: a multicentric retrospective study of 30 French cases and follow-up of the renal function]

PURPOSE

Idiopathic retroperitoneal fibrosis (IRF) is an inflammatory disorder, affecting the aorta and the surrounding vessels and tissues. The prognosis is mainly driven by the risks of chronic kidney disease and relapse. Our aim was to assess the prevalence of chronic kidney disease at follow-up.

METHODS

We retrospectively reviewed the medical records of patients diagnosed for IRF in Seine-Saint-Denis (France) between 1987 and 2011. We collected informations about presentation, radiologic findings and follow-up. Diagnosis of IRF was confirmed when all the following criteria were met: infiltration of the infrarenal aorta or iliac vessels, absence of aneurysmal dilation, lack of clinical suspicion of malignancy.

RESULTS

Thirty patients were identified, with a male/female ratio of 4.9. Mean age was 55±13 years old. The mean creatinine clearance was 66 mL/min/1.73 m(2) and the mean CRP was 45±36 mg/L. In 24 (80%) patients, the location of IRF was periaortic and periiliac. Eleven patients (37%) underwent a diagnostic biopsy, and 14 (47%) required an ureteral procedure. A mean follow-up of 63 months was available for 29 patients: 69% relapsed, 7 developed chronic renal disease (24%), and one died of urinary sepsis. Older age (P=0.023), diabetes (P=0.007), and initial renal insufficiency (P=0.05) were associated with a risk of chronic renal insufficiency.

CONCLUSION

The high frequency of relapses and chronic renal disease emphasizes the need of close follow-up in patients diagnosed with IRF.

Severe post-renal acute kidney injury, post-obstructive diuresis and renal recovery

Study Type--Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? The pathophysiology of post-renal acute kidney injury (PR-AKI), i.e. caused by urinary tract obstruction, has been extensively studied in animal models but clinical studies on this subject are outdated, and/or have focused on the mechanisms of 'post-obstructive diuresis' (POD), a potentially life-threatening polyuria that can develop after the release of obstruction. In severe PR-AKI, the risk of occurrence of POD is high. POD occurrence predicts renal recovery without the persistence of severe chronic kidney failure. In the present study, the occurrence of POD and the persistence of chronic renal sequelae could be predicted early from clinical variables at admission before the release of obstruction.

OBJECTIVE

• To identify predictors of post-obstructive diuresis (POD) occurrence or severe chronic renal failure (CRF) persistence after the release of urinary tract obstruction in the setting of post-renal acute kidney injury (PR-AKI).

PATIENTS AND METHODS

• Bi-centre retrospective observational study of all patients with PR-AKI treated in two intensive care units (ICUs) from 1998 to 2010. • Clinical, biological and imaging characteristics on admission and after the release of obstruction were analysed with univariate and, if possible, multivariate analysis to search for predictors of (i) occurrence of POD (diuresis >4 L/day) after the release of obstruction; (ii) persistence of severe CRF (estimated glomerular filtration rate <30 mL/min/1.73 m(2), including end-stage CRF) at 3 months.

RESULTS

• On admission, median (range) serum creatinine was 866 (247-3119) µmol/L. • POD occurred in 34 (63%) of the 54 analysable patients. On admission, higher serum creatinine (Odds ratio [OR] 1.002 per 1 µmol/L, 95% confidence interval [CI] 1.000-1.004, P = 0.004), higher serum bicarbonate (OR 1.36 per 1 mmol/L, 95% CI 1.13-1.65, P < 0.001), and urinary retention (OR 6.96, 95% CI 1.34-36.23, P = 0.01) independently predicted POD occurrence. • Severe CRF persisted in seven (21%) of the 34 analysable patients, including two (6%) cases of end-stage CRF. Predictors of severe CRF persistence after univariate analysis were: lower blood haemoglobin (P < 0.001) and lower serum bicarbonate (P = 0.03) on admission, longer time from admission to the release of obstruction (P = 0.01) and absence of POD (P = 0.04) after the release of obstruction.

CONCLUSIONS

• In severe PR-AKI treated in ICU, POD occurrence was a frequent event that predicted renal recovery without severe CRF. • POD occurrence or severe CRF persistence could be predicted early from clinical and biological variables at admission before the release of obstruction.

[Treatment of chronic kidney disease: therapeutic strategy]

The objectives are to slow the progression of chronic kidney disease (CKD), to take all the cardiovascular risk factors into account, to screen for and treat specific complications and to prepare, if necessary, for renal replacement treatment (transplantation or dialysis). The principal treatment targets are: blood pressure less than 130/80 mmHg and proteinuria less than 0.5 g/day (ratio of proteinuria/creatinuria <50mg/mmol). The first-line treatment to reach these goals is angiotensin conversion enzyme inhibitors (ACE inhibitors), combined with diet and other life style changes. The periodicity of clinical and laboratory assessments depends on the CKD stage, the speed of disease progression and the need to reassess the impact of therapeutic interventions. Comprehensive multidisciplinary management can slow or even stop the progression of CKD and reduce its cardiovascular complications, which are the leading cause of death in these patients.

Glomerular lesions in patients with sickle cell disease

Sickle cell disease (SCD) is an increasing cause of chronic kidney disease, but the spectrum of glomerular lesions and their underlying mechanisms remain poorly described. We reviewed 18 renal biopsies from patients with SCD and glomerular involvement and studied the expression of hypoxic markers in the biopsy specimens. Four histopathologic variants were distinguished: focal segmental glomerulosclerosis (FSGS) (39%), membranoproliferative glomerulonephritis (28%), thrombotic microangiopathy glomerulopathy (17%), and specific sickle cell disease glomerulopathy (17%). Chronic organ damage and history of acute chest syndrome were associated with the occurrence of SCD glomerulopathy. All patients exhibited macroalbuminuria but only 6 patients displayed impaired renal function. SCD was not associated with a specific FSGS histologic variant. Long-term follow-up analysis revealed that 50% of patients exhibited chronic kidney disease. Regardless of the histologic variants, immunohistochemistry did not reveal a specific induction of hypoxic markers (inducible nitric oxide synthase [iNOS], nitrotyrosine, hypoxia-inducible factor [HIF]-1 alpha) at the time of renal biopsy. This large study shows that a wide spectrum of glomerular lesions is associated with SCD. Whatever lesions are observed, the renal prognosis is poor, and early renoprotective treatment is necessary. Hypoxic state does not seem to play a key role in the progression of glomerular lesions, but its potential role at an early stage of glomerular injury requires further investigation.

Rituximab in severe lupus nephritis: early B-cell depletion affects long-term renal outcome

BACKGROUND AND OBJECTIVES

Standard treatment for lupus nephritis, including corticosteroids and cyclophosphamide, is efficient but is still associated with refractory or relapsing disease, or severe deleterious effects. Rituximab, a monoclonal chimeric anti-B cell antibody, is increasingly used in patients with lupus nephritis, but reported series were small and had a short follow-up.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The authors analyzed clinical and histologic data of 20 patients who were treated with rituximab for lupus nephritis and followed up for at least 12 mo.

RESULTS

Nineteen women and one man received rituximab as induction treatment for an active class IV (15 cases) or class V (5 cases) lupus nephritis. Rituximab was given for lupus nephritis refractory to standard treatment (12 cases), for relapsing disease (6 cases), or as first-line treatment (2 cases). Three patients received cyclophosphamide concomitantly with rituximab. Ten received new injections of rituximab as maintenance therapy. Side effects included mainly five infections and four moderate neutropenias. After a median follow-up of 22 mo, complete or partial renal remission was obtained in 12 patients (60%). Lupus nephritis relapsed in one patient, who responded to a new course of rituximab. The achievement of B cell depletion 1 mo after rituximab, which negatively correlated with black ethnicity and hypoalbuminemia, was strongly associated with renal response. Rapidly progressive glomerulonephritis did not respond to rituximab.

CONCLUSION

Rituximab is an interesting therapeutic option in relapsing or refractory lupus nephritis when early B cell depletion is obtained.

Renal sarcoidosis: clinical, laboratory, and histologic presentation and outcome in 47 patients

We conducted the current study to investigate the clinical, laboratory, and histologic features at presentation and the outcome of renal sarcoidosis (RS). Exhaustive retrospective data were collected by the French Sarcoidosis Group. Forty-seven adult patients were assessed (30 male/17 female, M/F ratio: 1.76). Median estimated glomerular filtration rate (eGFR) was 20.5 mL/min per 1.73 m(2) (range, 4-93 mL/min per 1.73 m(2)). Moderate proteinuria was found in 31 (66%) patients (median, 0.7 g/24 h; range, 0-2.7 g/24 h), microscopic hematuria in 11 (21.7%) patients, aseptic leukocyturia in 13 (28.7%) patients. Fifteen of 47 (32%) patients had hypercalcemia (>2.75 mmol/L). Eleven of the 22 (50%) patients diagnosed between June and September had hypercalcemia compared with only 4 of the 25 (16%) cases diagnosed during the other months (p < 0.001). Thirty-seven patients presented with noncaseating granulomatous interstitial nephritis (GIN), and 10 with interstitial nephritis without granulomas. Apart from hypercalcemia, the clinical phenotype was also remarkable for the high frequency of fever at presentation. All patients initially received prednisone (median duration, 18 mo), 10 received intravenous pulse methylprednisolone. eGFR increased from 20 +/- 19 to 44 +/- 24.7 mL/min per 1.73 m(2) at 1 month (p < 0.001, n = 38), to 47 +/- 19.9 mL/min per 1.73 m(2) at 1 year (p < 0.001, n = 46), to 49.13 +/- 25 mL/min per 1.73 m(2) at last follow-up (p < 0.001, n = 47). A complete response to therapy at 1 year and at last follow-up was strongly correlated with complete response at 1 month (p < 0.01). Renal function improvement was inversely related to initial histologic fibrosis score. A complete response to therapy at 1 year was strongly correlated with hypercalcemia at presentation (p = 0.003). Relapses were purely renal (n = 3) and purely extrarenal (n = 10) or both (n = 4), often a long time after presentation, with in some cases severe cardiac or central nervous system involvement. We conclude that hypercalcemia and fever at presentation are often associated with RS; RS is most often and permanently responsive to corticosteroid treatment, but some degree of persistent renal failure is highly frequent and its degree of severity in the long run is well predicted from both histologic fibrotic renal score and response obtained at 1 month.

Renal lesions associated with IgM-secreting monoclonal proliferations: revisiting the disease spectrum

BACKGROUND AND OBJECTIVES

Since the first description of pathology of the kidney in Waldenström disease in 1970, there have been few reports on kidney complications of IgM-secreting monoclonal proliferations. Here, we aimed to revisit the spectrum of renal lesions occurring in patients with a serum monoclonal IgM.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Fourteen patients with a circulating monoclonal IgM and a kidney disease related to B cell proliferation were identified retrospectively. Demographic, clinical, and laboratory data were assessed for each patient at the time of kidney biopsy.

RESULTS

Seven patients had a nephrotic syndrome. Patients without nephrotic syndrome all had impaired renal function. Mean serum creatinine was 238 micromol/L. For five patients, the diagnosis of monoclonal IgM preceded the kidney disease by 28.8 mo (range 12 to 60). Seven patients had Waldenström disease, two had a small B cell non-Hodgkin lymphoma, one had an IgM-excreting multiple myeloma, one had a marginal zone B cell lymphoma, and three had an IgM-related disorder. Renal lesions included (1) intracapillary monoclonal deposits disease with granular, electron-dense IgM thrombi occluding capillary lumens (5); (2) atypical membranoproliferative glomerulonephritis (3); (3) lambda light chain amyloidosis (2) associated with mu deposits in one patient; (4) acute tubular necrosis (1); and (5) CD20(+) lymphomatous infiltration (3). Remission of the nephrotic syndrome was attained in three of seven patients, and renal function improved after chemotherapy.

CONCLUSIONS

Although renal complications of IgM proliferations are rare, a wide spectrum of kidney lesions is observed, without correlation with the type of hematologic disorder.

Syndrome de Gitelman et grossesse: à propos d'un cas et revue de la littérature

Gitelman syndrome (GS) is a tubulopathy characterized by hypokaliemia, hypomagnesiemia, metabolic alkalosis and hypocalciuria. We report a case of a 33-year-old pregnant woman with Gitelman Syndrome. Oral potassium chloride and magnesium citrate were prescribed and the course of the pregnancy was uneventful with vaginal delivery at term. The impact of GS on the physiologic adaptations to pregnancy is not well-known, with few reports to date. Monitoring of serum potassium and magnesium levels with supplementation, amniotic fluid and fetal growth is required to prevent obstetrical and fetal complications in a patient with GS.

Renal granulomatoses: a retrospective study of 40 cases and review of the literature

Renal granulomatoses represent 0.5%-0.9% of nephropathies examined by renal biopsies. Granulomas can be isolated to the kidney or associated with other tissue involvement. We describe 40 consecutive patients with renal granulomatoses, associated with pauci-immune crescentic glomerulonephritis in 2 patients and with vasculitis in another, seen in northeastern Paris hospitals between January 1991 and February 2004. The criterion for inclusion was the presence of 1 or more epithelioid granulomas in the renal interstitium. Our population of 25 men and 15 women had a median age of 53 years. All patients suffered from renal insufficiency with median creatininemia of 236.8 micromol/L (range, 124-805 micromol/L), associated with hypertension (25%), median proteinuria of 0.6 g/24 h (range, 0.08-3.00 g/24 h), microscopic hematuria (15%) and leukocyturia (22.5%). Histologic examination of extrarenal specimens detected granulomas in 82.4% of the bronchial biopsies taken, and in 100% of the 2 skin biopsies, the 2 lymph-node biopsies, and the liver and colon biopsies. The following etiologies were retained: sarcoidosis for 20 (50%) patients, drug-induced for 7 (17.5%), tuberculosis for 3 (7.5%), Wegener granulomatosis for 2 (5%), and leprosy, Mycobacterium avium infection, and Crohn disease for 1 (2.5%) patient each. No etiology could be identified for 5 (12.5%) patients. Treatment must be adapted to the etiology of each case. The renal outcome after treatment was generally favorable, with the estimated median creatinine clearance increasing from 26 mL/min (range, 5.4-80.0 mL/min) to 46.5 mL/min (range, 0-118 mL/min) after a median follow-up of 35.5 months (range, 3-158 mo). Nonetheless, 32 patients had persistent renal insufficiency; 1 required hemodialysis and another underwent renal transplantation. Sarcoidosis and medications are the most common causes of renal granulomatosis. Idiopathic and drug-induced forms do not relapse after treatment discontinuation, and remission persists at long-term follow-up.

[Surgical learning curve for creation of vascular accesses for haemodialysis: value of medico-radio-surgical collaboration]

INTRODUCTION

Creation of a vascular access (VA) for haemodialysis is a surgical procedure which comprises a failure rate related to the quality of the vessels and the operator's experience. The authors report the first 2 years of a young urologist's experience with this procedure in a local hospital in collaboration with the nephrology team.

PATIENTS AND METHODS

Patients undergoing creation of VA were divided into 2 chronological groups. The patient's age and gender, the cause of renal failure, the presence of diabetes, clinical examination of the upper limb, preoperative assessment of upper limb vessels, the type of anaesthesia, the operating time and the start of dialysis after the operation, as well as the functional results of the VA at 6 months were studied. Results concerning the patients of the first period were discussed by the operator and the nephrology team.

RESULTS

During the first 9 months, 28 patients were operated, corresponding to 36 operations including 32 direct fistulas. Over the following 15 months, 61 patients were operated, with the creation of 63 VAs, including 55 direct fistulas. The failure rate (thrombosis or non-functioning VA) decreased from 32.1% to 11.1% (p=0.07), while the 2 groups were globally comparable.

CONCLUSION

Evaluation of a new surgical procedure shows a number of failures, as for all learning curves. However, it helps to improve the results. Collaboration with nephrologists must comprise a discussion allowing the acceptance of certain failures, as they reflect compliance with a strategy of preservation of the vascular capital and a rational attempt to avoid a non-essential proximal access or bypass graft. The support of a motivated radiology team (preoperative assessment and management of complications) and the assistance of a more experienced operator are essential.

[Medical management of post-obstruction diuresis syndromes]

The presence of urinary tract obstruction affects the proximal urinary tract by altering renal filtration and excretion functions, resulting in accumulation of electrolytes. Many pathophysiological mechanisms are also involved during obstruction and may be expressed secondarily. For example, relief of obstruction, which restores free flow of urine, is accompanied by marked diuresis and electrolyte disorders. The post-obstruction diuresis syndrome can lead to dehydration, or even shock and acute renal failure. Strict and specialized monitoring is required during the post-obstruction phase. Medical management is designed to avoid serious haemodynamic and metabolic disorders.

[Cholesterol crystal embolism disease, diagnostic criteria]

FROM AN EPIDEMIOLOGICAL POINT OF VIEW: With the aging of the population and increased indications for angioplasty or anticoagulant therapy, the incidence of cholesterol crystal embolism is going to increase. FROM A CLINICAL POINT OF VIEW: A systemic disease related to multiorgan distal ischemia, cholesterol crystal embolism has multiple facets. Rapidly progressive renal failure, malignant hypertension in the elderly, mesenteric ischemia, acute pulmonary edema, cutaneous ischemia or encephalopathy symptomatology may reveal cholesterol crystal embolism. THE IMPORTANCE OF DIAGNOSIS: The occurrence of such symptoms in poly-vascular patients, notably following exposure to inductive factors such as arterial catheterism, anticoagulant therapy or cardiac or vascular surgery is highly suggestive of the diagnosis. The lack of its knowledge can lead to inappropriate anticoagulant therapy and useless arteriography, which may even prolong or worsen cholesterol crystal embolism.

Regulation by glucocorticoids of expression and activity of rBSC1, the Na+-K+(NH4+)-2Cl- cotransporter of medullary thick ascending limb

To assess whether glucocorticoids regulate rBSC1, the apical Na(+)-K(+)(NH(4)(+))-2Cl(-) cotransporter of kidney medullary thick ascending limb (MTAL), studies were performed in normal rats, adrenalectomized (ADX) rats, and ADX rats infused with dexamethasone for 6 days. The effects of dexamethasone on rBSC1 were also studied in vitro using isolated rat MTAL segments. Cotransport activity was estimated by intracellular pH measurements; rBSC1 protein was quantified in MTAL crude membranes by immunoblotting analysis, and mRNA was quantified by quantitative reverse transcription-polymerase chain reaction. The abundance of rBSC1 protein and mRNA increased in ADX rats infused with dexamethasone compared with ADX rats (p < 0. 04). In addition, application of dexamethasone for 1-3 h to MTALs caused rBSC1 protein and mRNA abundance and cotransport activity to significantly increase in a hyperosmotic medium (450 mosmol/kg of H(2)O) containing 0.7 nm arginine vasopressin, which is an in vitro experimental condition that resembles the in vivo MTAL environment. Results obtained in various media and with 8-bromo-cAMP indicated that stimulation of rBSC1 expression by glucocorticoids required interactions between glucocorticoid receptor- and cAMP-dependent factors. Up to 100 nm d-aldosterone had no effect on cotransport activity in vitro. Thus glucocorticoids directly stimulate MTAL rBSC1 expression and activity, which contributes to glucocorticoid-dependent effects on the renal regulation of acid-base balance and urinary concentrating ability.

Supportive treatment improves survival in multivisceral cholesterol crystal embolism

Disseminated cholesterol crystal embolism (CCE) is a devastating complication of atherosclerosis that is often considered beyond therapeutic resources. We designed and implemented a treatment protocol based on an analysis of the main causes of death in disseminated CCE with renal involvement. From 1985 to 1996, we applied this protocol in 67 consecutive atherosclerotic patients admitted to our renal intensive care unit for acute renal failure (serum creatinine level, 6 +/- 2.5 mg/dL) accompanied by signs and symptoms of CCE. The other principal clinical features in these patients were cardiac failure with pulmonary edema (61%), gastrointestinal ischemia (33%), cutaneous ischemia (90%), and retinal cholesterol embolism (22%). Disseminated CCE followed one or several precipitating factors, including angiographic procedure(s) (85%), anticoagulant treatment (76%), and cardiovascular surgery (33%). Our treatment schedule systematically addressed the identified causes of death in these patients. (1) To avoid CCE recurrence, any form of anticoagulant treatment was withdrawn, and aortic catheterization and surgery were proscribed. (2) To treat or prevent cardiac failure, a high-dose vasodilator regimen was instituted, including angiotensin-converting enzyme (ACE) inhibitors. In case of cardiac failure refractory to vasodilators, loop diuretics were added and, if necessary, overhydration was corrected by ultrafiltration/hemodialysis (11 patients). (3) To avoid cachexia, severe metabolic disorders were treated by hemodialysis (41 patients), and special attention was given to providing enteral or parenteral nutritional support. Patients with declining general status and laboratory evidence of inflammation, as well as those with new episodes of CCE, were treated with corticosteroids. Statistical analysis found a significant correlation between the requirement for hemodialysis and previous anticoagulation, degree of renal insufficiency, and severity of cardiac failure. Conversely, there was no correlation between requirement for hemodialysis and ACE inhibitor treatment or presence of atherosclerotic renal artery stenosis/thrombosis. The inhospital mortality rate was 16%. There were no clinical or laboratory elements found on admission that were predictive of inhospital mortality. Among survivors, 32% had to remain on maintenance hemodialysis therapy for irreversible chronic renal failure. Including initial hospitalization, the 1-year survival rate was 87%, which compares favorably with reports in the literature indicating a first-year mortality rate of 64% to 81%. Overall follow-up was 19 +/- 20 months, ranging from 1 to 74 months. The 4-year survival rate was 52%. We conclude that an intensive-care, specific-treatment schedule reduces mortality in multivisceral cholesterol embolism.

[Cholesterol crystal embolism during treatment with low-molecular-weight heparin]

BACKGROUND

Cholesterol crystal embolism is often an iatrogenic complication in ulcerated atherosclerosis of the aorta.

CASE REPORTS

Two cases of multi-organ embolism of cholesterol crystals were histologically proven in patients treated with low-molecular-weight heparin. Both patients had acute renal failure, hypertension with acute pulmonary edema, skin necrosis and ischemia of the digestive tract. Outcome was favorable after discontinuing anticoagulants, symptomatic treatment, definitive hemodialysis and low-dose corticosteroids.

DISCUSSION

These two cases are the first reported in the literature of cholesterol crystal embolism occurring during prophylactic treatment with low-molecular-weight heparin. They demonstrate that there is a risk of severe cholesterol embolism in high-risk patients after administration of low-molecular-weight heparin as for non-fractionated heparin, fibrinolytics, arteriography and cardiovascular surgery. Low-molecular-weight heparin thus should not be used in patients with a diagnosis of cholesterol crystal embolism.

Sulfadiazine-induced crystalluria in AIDS patients with toxoplasma encephalitis

Toxoplasma encephalitis is the most common opportunistic infection of the central nervous system in patients with AIDS. The treatment of choice is a combination of sulfadiazine and pyrimethamine. We present here four patients with AIDS treated for toxoplasmic encephalitis who developed sulfadiazine-induced crystalluria. This complication was rapidly reversible with rehydration and urine alkalinization. Patients with AIDS treated with high doses of sulfadiazine should be adequately hydrated, and their urinary pH maintained above 7.5 to prevent sulfadiazine-induced crystalluria.