Systemic and Local Medical or Surgical Therapies for Ear, Nose and/or Throat Manifestations in ANCA-Associated Vasculitis: A Systematic Literature Review

BACKGROUND

Ear, nose and throat (ENT) manifestations are common in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), yet how to treat these manifestations remains controversial. Therefore, we systematically reviewed the literature on the efficacy of therapies on ENT manifestations in AAV.

METHODS

A systematic review was conducted in accordance with the PRISMA guidelines, searching Medline, Embase and Cochrane libraries, including clinical studies between January 2005 and January 2022, in adults with AAV and ENT involvement, reporting on the effects of local and systemic therapy. The critical appraisal was performed using tools provided by the Cochrane Library and the level of evidence (LoE) was scored according to the Oxford Centre for Evidence-based Medicine.

RESULTS

After screening 5609 identified studies, 136 full-text articles were assessed. Finally, 31 articles were included for critical appraisal and data-extraction. Nearly all studies (n = 29) were retrospective and scored low on LoE. The included studies evaluated local interventions (n = 11), glucocorticoids combined with conventional synthetic disease modifying anti-rheumatic drugs (csDMARDs) (n = 8), rituximab (n = 6), or mepolizumab (n = 6). Due to heterogeneity across studies meta-analysis was not performed. Four studies on mepolizumab for sinonasal symptoms (n = 92) showed response in 33-100% and relapse in 35%. Local therapy for subglottic stenosis was effective in 80-100% of patients in 11 studies (n = 157), but relapses were common (up to 83%). In five studies, hearing improvement was observed in 56-100%, with better outcomes when glucocorticoids were combined with csDMARDs compared to glucocorticoids only.

CONCLUSION

Response rates of ENT manifestations varied widely in studies and relapses were observed frequently. Heterogeneity among studies impaired comparison.

Immunosuppressive Therapies in Ear, Nose, and Throat Involvement in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: Results From a Multicenter Retrospective Cohort Study

OBJECTIVE

The aim of this study was to evaluate the response of ear, nose, and throat (ENT) symptoms to different immunosuppressive therapies in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV).

METHODS

In this cohort study, patients with AAV treated between January 2010 and April 2020 at 2 Dutch hospitals were included. Clinical, histological, and laboratory data were collected retrospectively. ENT involvement was defined as follows: (1) ≥ 1 ENT symptom according to the Birmingham Vasculitis Activity Score (version 3; BVAS3), and/or (2) presence of saddle nose deformity. Associations between therapy and ENT activity were assessed using logistic regression analysis.

RESULTS

A total of 320 patients with AAV were included, of whom 209 (65.3%) had ENT involvement at some point throughout the disease course. In these 209 patients, median age at disease onset was 52.0 years (IQR 40.0-62.0) and 45.5% were male. Median BVAS3 was 12.0 (IQR 6.0-18.0) at diagnosis. Despite immunosuppressive therapy, 50% (n = 77) of the patients had ENT symptoms at relapse and 29.1% (n = 59) had ENT activity at their last visit. No statistically significant difference in ENT activity at last visit was observed between patients treated with oral or intravenous cyclophosphamide (CYC, n = 137) compared to rituximab (RTX, n = 55; adjusted odds ratio 0.59, 95% CI 0.33-1.06; P = 0.08). Lower age at disease onset and female sex were independently associated with ENT activity at last follow-up.

CONCLUSION

In this cohort, CYC and RTX therapy had similar therapeutic effects on ENT symptoms in AAV. Persistent ENT activity is a common feature despite immunosuppressive therapy.

Key elements in selection of pre-dialysis patients for home dialysis

BACKGROUND

Most pre-dialysis patients are medically eligible for home dialysis, and home dialysis has several advantages over incentre dialysis. However, accurately selecting patients for home dialysis appears to be difficult, since uptake of home dialysis remains low. The aim of this study was to investigate which medical or psychosocial elements contribute most to the selection of patients eligible for home dialysis.

METHODS

All patients from a Dutch teaching hospital, who received treatment modality education and subsequently started dialysis treatment, were included. The pre-dialysis programme consisted of questionnaires for the patient, nephrologist and social worker, followed by an assessment of eligibility for home dialysis by a multidisciplinary team. Clinimetric assessment and logistic regression were used to identify domains and questions associated with home dialysis treatment.

RESULTS

A total of 135 patients were included, of whom 40 were treated with home dialysis and 95 with incentre haemodialysis. The key elements associated with long-term home dialysis treatment were part of the domains 'suitability of the housing', 'self-care', 'social support' and 'patient capacity', with adjusted odds ratios ranging from 0.13 for negative to 18.3 for positive associations.

CONCLUSION

The assessment of contraindications by a nephrologist followed by the assessment of possibilities by a social worker or dialysis nurse who investigates four key elements, ideally during a home visit, and subsequent detailed education offered by specialized nurses is an optimal way to select patients for home dialysis.

Developments in the Histopathological Classification of ANCA-Associated Glomerulonephritis

BACKGROUND AND OBJECTIVES

The histopathologic classification for ANCA-associated GN distinguishes four classes on the basis of patterns of injury. In the original validation study, these classes were ordered by severity of kidney function loss as follows: focal, crescentic, mixed, and sclerotic. Subsequent validation studies disagreed on outcomes in the crescentic and mixed classes. This study, driven by the original investigators, provides several analyses in order to determine the current position of the histopathologic classification of ANCA-associated GN.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A validation study was performed with newly collected data from 145 patients from ten centers worldwide, including an analysis of interobserver agreement on the histopathologic evaluation of the kidney biopsies. This study also included a meta-analysis on previous validation studies and a validation of the recently proposed ANCA kidney risk score.

RESULTS

The validation study showed that kidney failure at 10-year follow-up was significantly different between the histopathologic classes (P<0.001). Kidney failure at 10-year follow-up was 14% in the crescentic class versus 20% in the mixed class (P=0.98). In the meta-analysis, no significant difference in kidney failure was also observed when crescentic class was compared with mixed class (relative risk, 1.15; 95% confidence interval, 0.94 to 1.41). When we applied the ANCA kidney risk score to our cohort, kidney survival at 3 years was 100%, 96%, and 77% in the low-, medium-, and high-risk groups, respectively (P<0.001). These survival percentages are higher compared with the percentages in the original study.

CONCLUSIONS

The crescentic and mixed classes seem to have a similar prognosis, also after adjusting for differences in patient populations, treatment, and interobserver agreement. However, at this stage, we are not inclined to merge the crescentic and mixed classes because the reported confidence intervals do not exclude important differences in prognosis and because an important histopathologic distinction would be lost.

A Dutch consensus statement on the diagnosis and treatment of ANCA-associated vasculitis

INTRODUCTION

Despite the availability of several guidelines on the diagnosis and treatment of antineutrophil cytoplasmic antibody-associated vasculitis (AAV), clinical routine practice will only improve when an implementation strategy is in place to support clinical decision making and adequate implementation of guidelines. We describe here an initiative to establish national and multidisciplinary consensus on broad aspects of the diagnosis and treatment of AAV relevant to daily clinical practice in the Netherlands.

METHODS

A multidisciplinary working group of physicians in the Netherlands with expertise on AAV addressed the broad spectrum of diagnosis, terminology, and immunosuppressive and non-immunosuppressive treatment, including an algorithm for AAV patients. Based on recommendations from (inter)national guidelines, national consensus was established using a Delphi-based method during a conference in conjunction with a nationally distributed online consensus survey. Cut-off for consensus was 70% (dis)agreement.

RESULTS

Ninety-eight professionals were involved in the Delphi procedure to assess consensus on 50 statements regarding diagnosis, treatment, and organisation of care for AAV patients. Consensus was achieved for 37/50 statements (74%) in different domains of diagnosis and treatment of AAV including consensus on the treatment algorithm for AAV.

CONCLUSION

We present a national, multidisciplinary consensus on a diagnostic strategy and treatment algorithm for AAV patients as part of the implementation of (inter)national guideline-derived recommendations in the Netherlands. Future studies will focus on evaluating local implementation of treatment protocols for AAV, and assessments of current and future clinical practice variation in the care for AAV patients in the Netherlands.

ANCA-Associated Glomerulonephritis: Risk Factors for Renal Relapse

Relapse in ANCA-associated vasculitis (AAV) has been studied previously, but there are few studies on renal relapse in particular. Identifying patients at high risk of renal relapse may aid in optimizing clinical management. We investigated which clinical and histological parameters are risk factors for renal relapse in ANCA-associated glomerulonephritis (AAGN). Patients (n = 174) were newly diagnosed and had mild–moderate or severe renal involvement. Data were derived from two trials of the European Vasculitis Society: MEPEX and CYCAZAREM. The Cox regression model was used to identify parameters increasing the instantaneous risk (= rate) of renal relapse (useful for instant clinical decisions). For identifying predictors of renal relapse during follow-up, we used Fine & Gray’s regression model. Competing events were end-stage renal failure and death. The cumulative incidence of renal relapse at 5 years was 9.5% (95% CI: 4.8–14.3%). In the Cox model, sclerotic class AAGN increased the instantaneous risk of renal relapse. In Fine & Gray’s model, the absence of interstitial infiltrates at diagnosis was predictive for renal relapse. In this study we used two different models to identify possible relationships between clinical and histopathological parameters at time of diagnosis of AAV with the risk of experiencing renal relapse. Sclerotic class AAGN increased the instantaneous risk of renal relapse. This association is most likely due to the high proportion of sclerosed glomeruli reducing the compensatory capacity. The absence of interstitial infiltrates increased the risk of renal relapse which is a warning sign that patients with a relatively benign onset of disease may also be prone to renal relapse. Renal relapses occurring in patients with sclerotic class AAGN and renal relapses occurring in patients without interstitial infiltrates were mutually exclusive, which may indicate that they are essentially different.

GUIDE, a structured pre-dialysis programme that increases the use of home dialysis

Background

Despite the many advantages it offers, the percentage of dialysis patients that receive home dialysis [peritoneal dialysis (PD) or home haemodialysis (HHD)] in the Netherlands has declined over the last decade. Pre-dialysis education could stimulate the use of home dialysis. This article presents the results of the pre-dialysis programme GUIDE, with regard to the following question: Does the implementation of a structured pre-dialysis programme with a home-focused approach increase the number of pre-dialysis patients that choose and receive home dialysis?

Methods

The GUIDE process starts when a patient has an eGFR of 15 mL/min/1.73 m². The process begins with a home visit from a case manager and the completion of questionnaires by the patient, the case manager and the nephrologist. A multidisciplinary meeting (MDM) is held to determine a specific patient profile (or treatment recommendation). This is followed by patient education, a second MDM and finally the selection of the treatment by the patient and the nephrologist. This retrospective observational study describes the selection process of all patients that received a treatment recommendation between 12 September 2013 and 18 December 2014 at Meander Medical Centre. Data were collected by file research and analysis of questionnaires.

Results

One hundred and two patients were included. They started the process at a mean eGFR of 12.3 mL/min/1.73 m². Home dialysis was recommended for 62.8% of the patients who were advised to have dialysis treatment. Of the patients that opted for dialysis, 34.2% chose PD and 8.2% chose HHD; 22.9% started home dialysis as their first therapy, compared with 17.6% in the months before implementation of GUIDE. Finally, 32.1% of the patients that received dialysis therapy received home dialysis. In the months before GUIDE, an average of just 19.5% of the patients that received dialysis received home dialysis.

Conclusions

In comparison to historical data, the pre-dialysis programme GUIDE increases the number of patients that choose and receive home dialysis.

Twenty-five years of RENHIS: a history of histopathological studies within EUVAS

In the early 1990s, an international working group of experienced renal pathologists, the Renal Histology group, set up a scoring system for biopsies with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis. This scoring system subdivided glomerular, interstitial and vascular lesions and served as a tool for the evaluation of all renal biopsies from studies of the European Vasculitis Study Group (EUVAS). Histopathological studies gave new insights into the prediction of renal outcome in patients with ANCA-associated glomerulonephritis. Percentage of normal glomeruli and a selected number of interstitial parameters were reliable predictors of long-term follow-up glomerular filtration rate in all studies. Out of these results, a histopathological classification distinguishing focal, crescentic, mixed and sclerotic classes of ANCA-associated glomerulonephritis was developed. Until today, 13 studies have validated this classification system. Future studies will try to determine if and how renal histology could be helpful in guiding treatment of ANCA-associated glomerulonephritis.

Revisiting the classification of clinical phenotypes of anti-neutrophil cytoplasmic antibody-associated vasculitis: a cluster analysis

BACKGROUND

Granulomatosis with polyangiitis (Wegener's) (GPA) and microscopic polyangiitis (MPA) are subgroups of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) defined historically by clinical and histological features. GPA and MPA are heterogeneous entities with overlapping phenotypes. To identify novel subgroupings, cluster analysis was used to explore the phenotypic spectrum of AAV.

METHODS

This study used a dataset of patients newly diagnosed as having GPA and MPA enrolled in five clinical trials. One cluster model included nine clinical baseline variables as input variables, and a second cluster model additionally included ANCA specificities. The clustering process involved multiple correspondence analyses followed by hierarchical ascendant cluster analysis. The clinical relevance of the generated clusters was analysed by their summary characteristics and outcomes.

RESULTS

The analyses involved data for 673 subjects: 396 (59%) with GPA and 277 (41%) with MPA. Both cluster models resulted in five partially redundant clusters of subjects, and the model including ANCA resulted in more pertinent separations. These clusters were named 'renal AAV with proteinase 3 (PR3)-ANCA' (40% of subjects), 'renal AAV without PR3-ANCA' (32%) and 'non-renal AAV' (12%), 'cardiovascular AAV' (9%) and 'gastrointestinal AAV' (7%). The five clusters had distinct death and relapse rates. On the basis of 4 variables, 651 subjects (97%) could be accurately allocated to 1 of the 5 classes.

CONCLUSIONS

This analysis suggests that AAV encompasses five classes associated with different outcomes. As compared with the traditional GPA-MPA separation, this classification system may better reflect the phenotypic spectrum of AAV.

Anti-plasminogen antibodies compromise fibrinolysis and associate with renal histology in ANCA-associated vasculitis

Antibodies recognizing plasminogen, a key component of the fibrinolytic system, associate with venous thrombotic events in PR3-ANCA vasculitis. Here, we investigated the prevalence and function of anti-plasminogen antibodies in independent UK and Dutch cohorts of patients with ANCA-associated vasculitis (AAV). We screened Ig isolated from patients (AAV-IgG) and healthy controls by ELISA. Eighteen of 74 (24%) UK and 10/38 (26%) Dutch patients with AAV had anti-plasminogen antibodies compared with 0/50 and 1/61 (2%) of controls. We detected anti-plasminogen antibodies in both PR3-ANCA- and MPO-ANCA-positive patients. In addition, we identified anti-tissue plasminogen activator (tPA) antibodies in 13/74 (18%) patients, and these antibodies were more common among patients with anti-plasminogen antibodies (P = 0.011). Eighteen of 74 AAV-IgG (but no control IgG) retarded fibrinolysis in vitro, and this associated with anti-plasminogen and/or anti-tPA antibody positivity. Only 4/18 AAV-IgG retarded fibrinolysis without harboring these antibodies; dual-positive samples retarded fibrinolysis to the greatest extent. Patients with anti-plasminogen antibodies had significantly higher percentages of glomeruli with fibrinoid necrosis (P < 0.05) and cellular crescents (P < 0.001) and had more severely reduced renal function than patients without these antibodies. In conclusion, anti-plasminogen and anti-tPA antibodies occur in AAV and associate with functional inhibition of fibrinolysis in vitro. Seropositivity for anti-plasminogen antibodies correlates with hallmark renal histologic lesions and reduced renal function. Conceivably, therapies that enhance fibrinolysis might benefit a subset of AAV patients.

Time-resolved spectra of dense plasma focus using spectrometer, streak camera, and CCD combination

A time-resolving spectrographic instrument has been assembled with the primary components of a spectrometer, image-converting streak camera, and CCD recording camera, for the primary purpose of diagnosing highly dynamic plasmas. A collection lens defines the sampled region and couples light from the plasma into a step index, multimode fiber which leads to the spectrometer. The output spectrum is focused onto the photocathode of the streak camera, the output of which is proximity-coupled to the CCD. The spectrometer configuration is essentially Czerny-Turner, but off-the-shelf Nikon refraction lenses, rather than mirrors, are used for practicality and flexibility. Only recently assembled, the instrument requires significant refinement, but has now taken data on both bridge wire and dense plasma focus experiments.

Histopathologic classification of ANCA-associated glomerulonephritis

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is the most common cause of rapidly progressive glomerulonephritis worldwide, and the renal biopsy is the gold standard for establishing the diagnosis. Although the prognostic value of the renal biopsy in ANCA-associated glomerulonephritis is widely recognized, there is no consensus regarding its pathologic classification. We present here such a pathologic classification developed by an international working group of renal pathologists. Our classification proposes four general categories of lesions: Focal, crescentic, mixed, and sclerotic. To determine whether these lesions have predictive value for renal outcome, we performed a validation study on 100 biopsies from patients with clinically and histologically confirmed ANCA-associated glomerulonephritis. Two independent pathologists, blinded to patient data, scored all biopsies according to a standardized protocol. Results show that the proposed classification system is of prognostic value for 1- and 5-year renal outcomes. We believe this pathologic classification will aid in the prognostication of patients at the time of diagnosis and facilitate uniform reporting between centers. This classification at some point might also provide means to guide therapy.

Different melatonin rhythms and sleep-wake rhythms in patients on peritoneal dialysis, daytime hemodialysis and nocturnal hemodialysis

BACKGROUND

Little comparative data on sleep-wake rhythms in different dialysis groups exist. The aim of this study was to investigate sleep-wake parameters measured with actigraphy and sleep questionnaires as well as melatonin rhythms in automated peritoneal dialysis, conventional daytime hemodialysis and nocturnal hemodialysis patients.

METHODS

Conventional daytime dialysis (n=20), nocturnal hemodialysis (n=13) and automated peritoneal dialysis patients (n=6) were included in the study. Melatonin in saliva was sampled at 5 time points (21:00, 23:00, 1:00, 7:00 and 9:00 h). Furthermore, actigraphy measurements and sleep questionnaires were performed. All parameters were tested by Kruskall-Wallis test (followed by post hoc Dunn test) to find significant differences (p<0.05).

RESULTS

Although most sleep parameters were impaired in all three groups, conventional daytime dialysis patients had the worst sleep. In nocturnal hemodialysis patients a normal nocturnal melatonin rise was found. In daytime hemodialysis and automated peritoneal dialysis patients this rise was absent.

CONCLUSIONS

The study showed impaired sleep parameters in all dialysis patient groups. As automated peritoneal dialysis is also performed during night time, the same effect on normalized melatonin was anticipated as was found in nocturnal hemodialysis. Melatonin seems to play a subordinate role in the sleep-wake rhythm of automated peritoneal dialysis patients.

Effects of nocturnal hemodialysis on melatonin rhythm and sleep-wake behavior: an uncontrolled trial

BACKGROUND

End-stage renal disease and its treatment are associated with sleep disturbances such as deterioration of the circadian sleep-wake pattern. Melatonin rhythm, which has an important role in this pattern, is disturbed. The nocturnal melatonin surge is absent in this population. Whether nocturnal in-center hemodialysis changes melatonin and sleep-wake rhythms is unknown.

STUDY DESIGN

A nonrandomized uncontrolled trial. Patients served as their own controls.

SETTING & PARTICIPANTS

Thirteen daytime hemodialysis patients (median age, 58 years; 5 women) from our hospital receiving conventional daytime hemodialysis 3 times weekly for 3 to 4 hours each session.

INTERVENTIONS

Six months of treatment with nocturnal in-center dialysis 4 nights/wk with 8-hour sessions.

OUTCOMES & MEASUREMENTS

At baseline, while still on conventional hemodialysis therapy, polysomnography was performed, sleep questionnaires were filled out, and melatonin concentration in saliva was obtained. After 6 months of in-center nocturnal hemodialysis, all measurements were repeated.

RESULTS

After 6 months of in-center nocturnal hemodialysis, polysomnography showed significant improvements in sleep efficiency (P = 0.05) and stage 3/4 sleep (P = 0.03) in comparison to t = 0. Trends in improvement of rapid-eye-movement sleep, awake time, and oxygen saturation were seen after 6 months of in-center nocturnal hemodialysis therapy. Sleep questionnaires showed a trend in improved sleep quality and daytime function. Patients were less exhausted during the daytime. The nocturnal melatonin surge was partially restored.

LIMITATIONS

Small sample size and a nonrandomized uncontrolled study design.

CONCLUSIONS

Patients after 6 months of in-center nocturnal hemodialysis had significant improvements in subjective and objective sleep parameters and partially restored nocturnal melatonin rhythm.

Community-onset Clostridium difficile-associated diarrhoea not associated with antibiotic usage--two case reports with review of the changing epidemiology of Clostridium difficile-associated diarrhoea

The emergence of hypervirulent strains of Clostridium difficile causing outbreaks in hospitals and nursing homes may result in a greater than before spread of the bacterium in the community. By consequence, the incidence of community-onset cases of Clostridium difficile-associated diarrhoea (CDAD) may increase outside known risk groups that are currently characterised by prior hospitalisation, prior antibiotic usage, older age and significant comorbidity. Here, we describe two case histories of community-onset CDAD. The first concerns a previously healthy young female with community-acquired CDAD without recent hospitalisation or antibiotic usage. The second patient developed diarrhoea in the community after discharge from a hospital where--in retrospect--an outbreak of CDAD occurred. The cases illustrate that CDAD should be included in the differential diagnosis of patients seeking care for community-onset diarrhoea, even in those without characteristic risk factors for CDAD.

Hypotheses on the etiology of antineutrophil cytoplasmic autoantibody associated vasculitis: the cause is hidden, but the result is known

The first description of what is now known as antineutrophil cytoplasmic autoantibody-associated necrotizing vasculitis appeared more than 140 yr ago. Since then, many aspects of the pathogenic pathway have been elucidated, indicating the involvement of antineutrophil cytoplasmic autoantibodies, but why antineutrophil cytoplasmic autoantibodies are produced in the first place remains unknown. Over the years, many hypotheses have emerged addressing the etiology of antineutrophil cytoplasmic antibody production, but no exclusive factor or set of factors can so far be held responsible. Herein is reviewed the most influential hypotheses regarding the causes of antineutrophil cytoplasmic antibody-associated vasculitis with the aim of placing in an epidemiologic background the different hypotheses that are centered on environmental and genetic influences.

Interobserver agreement of scoring of histopathological characteristics and classification of lupus nephritis

BACKGROUND

Assessing renal biopsies from patients with lupus nephritis (LN) is a difficult task and it is subject to interobserver variability. In this study the interobserver agreement amongst five nephropathologists was analysed.

METHODS

Five specialized nephropathologists scored 126 biopsies, comprising 87 first and 39 repeat biopsies from 87 patients with biopsy-proven proliferative LN, included in a randomized controlled trial. The interobserver agreement [expressed as intraclass correlation coefficients (ICC)] of the scored histopathological items was calculated. Also, the WHO1995 and ISN/RPS2003 classification systems for LN were compared, with extra attention being given to the comparison between patients with diffuse proliferative LN with either segmental (IV-S) or global (IV-G) lesions.

RESULTS

There was a wide range of agreement. A good interobserver agreement (ICC>0.6) was present in 15%, and a moderate interobserver agreement (ICC 0.4-0.6) in 31% of the scored items. The activity index for LN showed a good (ICC 0.716) and the chronicity index a moderate (ICC 0.494) interobserver agreement. Both classification systems showed low agreement, although consensus was easily reached. Patients classified as IV-S (n=15) had more favorable clinical parameters at study entry than those with class IV-G (n=57). Although suggested by others, we found no differences in outcome between these two subclasses.

CONCLUSIONS

This study shows that, although definitions were agreed upon beforehand, even specialized on nephropathologists have difficulties with scoring histopathological characteristics of LN, particularly with SLE the classification systems.

Chances of Renal Recovery for Dialysis-Dependent ANCA-Associated Glomerulonephritis

In patients who have anti-neutrophil cytoplasm autoantibody (ANCA)-associated glomerulonephritis and are on dialysis at time of diagnosis, renal function is sometimes insufficiently restored by immunosuppressive treatment, which often coincides with potentially lethal adverse effects. This study investigated the clinical and histologic variables that determine the chances of dialysis independence, dialysis dependence, or death after 12 mo in these patients. Sixty-nine patients who had ANCA-associated glomerulonephritis and were dialysis dependent at diagnosis received uniform, standard immunosuppressive therapy plus either intravenous methylprednisolone or plasma exchange. Eleven clinical and histologic variables were assessed. Univariate and binary logistic regression analyses were performed. Predictive parameters were entered into a two-step binary logistic regression analysis to differentiate among the outcomes of dialysis independence, dialysis dependence, or death. The point at which the chance of therapy-related death exceeded the chance of dialysis independence was determined. The chance of recovery exceeded the chance of dying in most cases. Intravenous methylprednisolone as adjunctive therapy plus <18% normal glomeruli and severe tubular atrophy increased the chance of therapy-related death over the chance of dialysis independence. Plasma exchange treatment plus severe tubular atrophy and <2% normal glomeruli increased the chance of therapy-related death over that of dialysis independence. Even with ominous histologic findings, the chance of renal recovery exceeds the chance of therapy-related death when these patients are treated with plasma exchange as adjunctive therapy.

Treatment with cyclophosphamide delays the progression of chronic lesions more effectively than does treatment with azathioprine plus methylprednisolone in patients with proliferative lupus nephritis

OBJECTIVE

To analyze the effect of treatment with either pulse cyclophosphamide (CYC) or azathioprine (AZA) combined with methylprednisolone (MP), on serial biopsy results in patients with proliferative lupus nephritis, and to evaluate the predictive value of various histopathologic and clinical parameters with regard to disease outcome.

METHODS

Biopsy specimens from patients with proliferative lupus nephritis, obtained at study entry and after 2 years of therapy, were scored according to a standardized method, and results assessed in relation to disease outcome.

RESULTS

Of the 87 patients originally enrolled, 39 underwent repeat biopsy. These patients were representative of the overall group, both at entry and at 2-year followup. The median activity index changed from 8.0 to 2.7 (no differences between the treatment groups). In the group treated with AZA plus MP (AZA group), the increase in the median chronicity index (from 2.7 to 3.8) was larger than that in the CYC group (from 2.7 to 3.0) (P = 0.050). In multivariate analyses, renal function at enrollment and after 2 years was the best predictor of renal function at the last visit, while none of the histopathologic variables (either at entry or at 2 years) added to this prediction. Comparing patients whose disease transitioned to class II with those who had persistent proliferative lupus nephritis revealed no differences between the treatment groups at either time point, and no clinical differences at 2 years. However, a higher serum creatinine level at entry and greater proteinuria at last visit were characteristic of patients who still had proliferative lupus nephritis at 2 years.

CONCLUSION

These results indicate that, although both CYC and AZA are effective in reducing active lesions in lupus nephritis, progression of chronic lesions is more effectively halted by CYC. Variables assessed by repeat biopsy do not predict clinical outcome.

Azathioprine/methylprednisolone versus cyclophosphamide in proliferative lupus nephritis. A randomized controlled trial

Until recently, intravenous cyclophosphamide pulses with oral corticosteroids were regarded standard therapy for proliferative lupus nephritis (LN). Azathioprine, a less toxic alternative, was never proven to be inferior. In the first Dutch lupus nephritis study (enrollment between 1995 and 2001), we randomized 87 proliferative LN patients to either cyclophosphamide pulses (750 mg/m(2), 13 pulses in 2 years) combined with oral prednisone (CY) or to azathioprine (2 mg/kg/day in 2 years) combined with intravenous pulses of methylprednisolone (3 x 3 pulses of 1000 mg) and oral prednisone (AZA). After a median follow-up of 5.7 years (interquartile range 4.1-7.2 years), doubling of serum creatinine was more frequent in the AZA group, although not statistically significant (relative risk (RR): 4.1, with 95% confidence interval (95% CI): 0.8-20.4). Relapses occurred more often in the AZA group (RR: 8.8, 95% CI: 1.5-31.8). Creatinine and proteinuria at last visit did not differ between the two treatment arms. Moreover, 88.4% of the patients in the AZA arm were still free of cyclophosphamide treatment. During the first 2 years, the frequency of remission was not different, but infections, especially herpes zoster virus infections (HZV) were more frequent in the AZA group. Parameters for ovarian function did not differ between the two groups. In conclusion, in this open-label randomized controlled trial, cyclophosphamide was superior to azathioprine with regard to renal relapses and HZV. At last follow-up, there were no differences in serum creatinine or proteinuria between the two groups. However, since our study lacked sufficient power, longer follow-up is needed to reveal putative differences.

Clinical and Histologic Determinants of Renal Outcome in ANCA-Associated Vasculitis: A Prospective Analysis of 100 Patients with Severe Renal Involvement

This study aimed to identify clinical and histologic prognostic indicators of renal outcome in patients with ANCA-associated vasculitis and severe renal involvement (serum creatinine >500 micromol/L). One hundred patients who were enrolled in an international, randomized, clinical trial to compare plasma exchange with intravenous methylprednisolone as an additional initial treatment were analyzed prospectively. Diagnostic renal biopsies were performed upon entry into the study. Thirty-nine histologic and nine clinical parameters were determined as candidate predictors of renal outcome. The end points were renal function at the time of diagnosis (GFR0) and 12 mo after diagnosis (GFR12), dialysis at entry and 12 mo after diagnosis, and death. Multivariate analyses were performed. Predictive of GFR0 were age (r = -0.40, P = 0.04), arteriosclerosis (r = -0.53, P = 0.01), segmental crescents (r = 0.35, P = 0.07), and eosinophilic infiltrate (r = -0.41, P = 0.04). Prognostic indicators for GFR12 were age (r = -0.32, P = 0.01), normal glomeruli (r = 0.24, P = 0.04), tubular atrophy (r = -0.28, P = 0.02), intraepithelial infiltrate (r = -0.26, P = 0.03), and GFR0 (r = 0.29, P = 0.01). Fibrous crescents (r = 0.22, P = 0.03) were predictive of dialysis at entry. Normal glomeruli (r = -0.30, P = 0.01) and treatment arm (r = -0.28, P = 0.02) were predictive of dialysis after 12 mo. No parameter predicted death. Both chronic and acute tubulointerstitial lesions predicted GFR12 in severe ANCA-associated glomerulonephritis, whereas plasma exchange was a positive predictor of dialysis independence after 12 mo for the entire patient group. Plasma exchange remained a positive predictor when patients who were dialysis dependent at presentation were analyzed separately (r = -0.36, P = 0.01). Normal glomeruli were a positive predictor of dialysis independence and improved renal function after 12 mo, indicating that the unaffected part of the kidney is vital in determining renal outcome.

Henoch-Schönlein purpura presenting as terminal ileitis and complicated by thrombotic microangiopathy

We report here on a 40-year-old woman with abdominal pain, low-grade fever, and diarrhea in whom the cutaneous features of Henoch-Schönlein purpura (HSP) appeared only a few days after acute abdominal symptoms. Endoscopy showed terminal ileitis, and histopathological examination of a biopsy of the ileum showed a picture of IgA vasculitis. The clinical course was further complicated by the development of microangiopathic hemolytic anemia, thrombocytopenia, and severe renal failure.

Treatment of refractory Wegener's granulomatosis with antithymocyte globulin (ATG): an open study in 15 patients

BACKGROUND

A subset of patients with Wegener's granulomatosis does not respond sufficiently to cyclophosphamide and glucocorticosteroids or suffers of intolerable side effects. Anecdotal data suggest that antithymocyte globulin (ATG) may be a treatment option for these patients. We now describe 15 patients treated with ATG for refractory Wegener's granulomatosis.

METHODS

Fifteen patients with histologically proven active refractory Wegener's granulomatosis (seven unresponsive to cyclophosphamide, eight intolerant) were treated with ATG by a protocol (SOLUTION protocol) designed by the European Vasculitis Study (EUVAS) Group.

RESULTS

Before ATG administration, patients had received a mean of 5.2 (range 2 to 7) different therapeutic approaches including glucocorticosteroids and cyclophosphamide in all and experimental therapies in six, without control of disease activity [2.8 (range 1 to 7) relapses during a disease duration of 63.2 (range 18 to 180) months]. Thirteen of 15 patients showed a favorable response to ATG with partial (N= 9) or complete (N= 4) remission. During a follow-up of 21.8 (range 6 to 68) months, seven patients relapsed after a mean of 8.4 (range 2 to 24) months (five minor and two major relapses). Six patients are free of relapse for 22.3 (range 7 to 64) months. Two patients died, 1 and 3 days following the first dose of ATG, due to pulmonary hemorrhage and infection (one each). Although further immunosuppressive treatment was required in all surviving patients, a less intensive regimen could be applied in 12. Beside fever and chills associated with the first gift of ATG, ATG was well tolerated, with infections being observed in five cases and serum sickness in two.

CONCLUSION

Anti-T-cell-directed treatment with ATG may be a therapeutic option for severe refractory Wegener's granulomatosis if simultaneous infections and fluid overload have been ruled out. In patients with alveolar hemorrhage, ATG should only be used under special caution.

Health-related quality of life in patients with systemic lupus erythematosus: development and validation of a lupus specific symptom checklist

Reliable and sensitive measures are needed to evaluate the quality of life (QoL) in patients with systemic lupus erythematosus (SLE). No lupus specific questionnaires are available. This study describes the development and validation of a disease-specific questionnaire for lupus patients, which assesses the presence and burden of 38 disease- and treatment-related symptoms: the SLE Symptom Checklist (SSC). Reliability and reproducibility were tested in respectively 87 and 28 stable SLE patients. The internal consistency (Cronbach's alpha coefficients 0.89) and test-retest reliability (Pearson product-moment correlation coefficient between 0.67 and 0.87) were satisfactory. Concurrent validity was supported by significant, but moderate correlations with other measures of subjective well-being and functional status. Responsiveness was measured in 17 patients with lupus nephritis treated with cyclophosphamide, at start of therapy and 1 year thereafter. A significant change in number of symptoms and total distress level was found. It is concluded that the SSC has satisfactory psychometric properties and appears suitable for both clinical and research purposes.

Increased albumin and fibrinogen synthesis rate in patients with chronic renal failure

BACKGROUND

Hypoalbuminemia and hyperfibrinogenemia are frequently observed in patients with chronic renal failure (CRF) and are both associated with cardiovascular diseases. The mechanisms responsible for hypoalbuminemia and hyperfibrinogenemia in CRF are unknown.

METHODS

In the present study, both albumin and fibrinogen kinetics were measured in vivo in predialysis patients (N = 6), patients on peritoneal dialysis (N = 7) and control subjects (N = 8) using l-[1-13C]-valine.

RESULTS

Plasma albumin concentration was significantly lower in patients on peritoneal dialysis compared to control subjects (P < 0.05). Plasma fibrinogen was significantly increased in both predialysis patients (P < 0.01) as well as patients on peritoneal dialysis (P < 0.001) in comparison to control subjects. In contrast to albumin, fibrinogen is only lost in peritoneal dialysate and not in urine. The absolute synthesis rates (ASR) of albumin and fibrinogen were increased in patients on peritoneal dialysis (ASR albumin, 125 +/- 9 mg/kg/day versus 93 +/- 9 mg/kg/day, P < 0.05; ASR fibrinogen, 45 +/- 4 mg/kg/day versus 29 +/- 3 mg/kg/day, P < 0.01) compared to control subjects. Albumin synthesis is strongly correlated with fibrinogen synthesis (r2 = 0.665, P < 0.0001, N = 21). In this study, the observed hypoalbuminemia in patients on peritoneal dialysis is likely not explained by malnutrition, inadequate dialysis, inflammation, metabolic acidosis, or insulin resistance. We speculate that peritoneal albumin loss is of relevance.

CONCLUSION

Synthesis rate of albumin and fibrinogen are coordinately up-regulated. Both albumin and fibrinogen are lost in peritoneal dialysis fluid. To compensate protein loss, albumin synthesis is up-regulated, but the response, in contrast to predialysis patients, does not fully correct plasma albumin concentrations in peritoneal dialysis patients. The increase in fibrinogen synthesis introduces an independent risk factor for atherosclerosis, since plasma fibrinogen pool is enlarged.

A randomized trial of maintenance therapy for vasculitis associated with antineutrophil cytoplasmic autoantibodies

BACKGROUND

The primary systemic vasculitides usually associated with autoantibodies to neutrophil cytoplasmic antigens include Wegener's granulomatosis and microscopic polyangiitis. We investigated whether exposure to cyclophosphamide in patients with generalized vasculitis could be reduced by substitution of azathioprine at remission.

METHODS

We studied patients with a new diagnosis of generalized vasculitis and a serum creatinine concentration of 5.7 mg per deciliter (500 micromol per liter) or less. All patients received at least three months of therapy with oral cyclophosphamide and prednisolone. After remission, patients were randomly assigned to continued cyclophosphamide therapy (1.5 mg per kilogram of body weight per day) or a substitute regimen of azathioprine (2 mg per kilogram per day). Both groups continued to receive prednisolone and were followed for 18 months from study entry. Relapse was the primary end point.

RESULTS

Of 155 patients studied, 144 (93 percent) entered remission and were randomly assigned to azathioprine (71 patients) or continued cyclophosphamide (73 patients). There were eight deaths (5 percent), seven of them during the first three months. Eleven relapses occurred in the azathioprine group (15.5 percent), and 10 occurred in the cyclophosphamide group (13.7 percent, P=0.65). Severe adverse events occurred in 15 patients during the induction phase (10 percent), in 8 patients in the azathioprine group during the remission phase (11 percent), and in 7 patients in the cyclophosphamide group during the remission phase (10 percent, P=0.94 for the comparison between groups during the remission phase). The relapse rate was lower among the patients with microscopic polyangiitis than among those with Wegener's granulomatosis (P=0.03).

CONCLUSIONS

In patients with generalized vasculitis, the withdrawal of cyclophosphamide and the substitution of azathioprine after remission did not increase the rate of relapse. Thus, the duration of exposure to cyclophosphamide may be safely reduced.

An index for renal outcome in ANCA-associated glomerulonephritis

BACKGROUND

The aim of this study is to analyze the predictive value of clinical, serological, and histological parameters for renal outcome in antineutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis by multivariate analysis and create an index valid for clinical use.

METHODS

Data from 160 patients with Wegener's granulomatosis, microscopic polyangiitis, and idiopathic rapidly progressive glomerulonephritis without immune deposits (renal-limited vasculitis) were collected. The Cockcroft formula was used to assess renal function expressed by glomerular filtration rate (GFR) at the time of renal biopsy (t = 0) and 1 year later (t = 1). Other clinical parameters were age, sex, and diagnosis. ANCA test results were scored as cytoplasmic ANCA/antiproteinase 3 (anti-PR3) or perinuclear ANCA/antimyeloperoxidase (anti-MPO) positive or negative. Histological data included normal glomeruli, fibrinoid necrosis, extracapillary proliferation, granulomas, interstitial edema, focal and diffuse infiltrates, fibrosis, tubular cylinders/casts, tubular atrophy, tubular necrosis, sclerosis, mesangial proliferation, mesangial matrix expansion, arteriosclerosis, and infiltrates in arterioles. In a separate analysis, we explored whether there were histological differences between patients with anti-PR3 and anti-MPO ANCA test results.

RESULTS

Forty percent of the variation in renal function at the time of biopsy can be explained by the presence or absence of tubular atrophy, normal glomeruli, fibrinoid necrosis, extracapillary proliferation, and age. Renal function at the time of biopsy is the best predictor for renal function at t = 1 in patients with ANCA-associated glomerulonephritis. Together with normal glomeruli, fibrinoid necrosis, and age, it explains more than 60% of the variation in GFR at t = 1. ANCA subtype has no independent contribution in predicting patient prognosis. Results translated into a clinically relevant index: GFR at t = 1 = 36.96 + 0.65* (GFR at t = 0) + 10.52 (if normal glomeruli present) + 7.72 (if fibrinoid necrosis present) - 0.42* (age).

CONCLUSION

The index created with results from this study provides an indication of renal outcome in patients diagnosed with ANCA-associated glomerulonephritis.

Glomerulonephritis in the vasculitides: advances in immunopathology

Systemic vasculitis refers to a condition of blood vessel inflammation, of which the causes are various. In a substantial number of cases, autoantibodies against neutrophil cytoplasm constituents (ANCAs) are present. The authors then refer to the systemic vasculitis as ANCA-associated systemic vasculitis. Renal disease is an unfavorable component, leading to dialysis dependency in a considerable number of patients. This review aims to summarize in brief what was reported about ANCA-associated vasculitis in the recent past. What the exact pathogenic role of ANCAs in the development of systemic vasculitis is remains uncertain, and it is still not clear how their presence leads to the histopathologic lesions called vasculitis.

Determinants of outcome in ANCA-associated glomerulonephritis: a prospective clinico-histopathological analysis of 96 patients

BACKGROUND

The predictive value of clinical and renal histological features for renal outcome in patients with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis was investigated in a prospective analysis of 96 patients with ANCA-associated vasculitis, and moderate renal involvement (creatinine <500 micromol/L).

METHODS

The extent of 39 histological features in 96 biopsies (performed at entry in a clinical trial) was scored by two independent observers, according to a standardized protocol. Age, gender, diagnosis, glomerular filtration rate at entry (GFR0), ANCA-specificity, proteinuria, and treatment of these 96 patients were also taken into account. Treatment was standardized and started after the biopsy was performed. End-points included renal function at 18 months (GFR18), GFR18 corrected for GFR0 (CORGFR18), and the occurrence of relapse or death.

RESULTS

Parameters that most strongly correlated with GFR18 were GFR0 (r = 0.67), interstitial fibrosis (r = -0.45), glomerulosclerosis (r = -0.37), and tubular atrophy (r = -0.36). Parameters that most strongly correlated with CORGFR18 were segmental (r = 0.45) and cellular (r = 0.30) crescents, and fibrinoid necrosis (r = 0.46). None of the clinical and histological features predicted the occurrence of relapse or death. By applying a stepwise linear multiple regression analysis, we designed a formula for the estimation of renal function at 18 months: GFR18 (mL/min) = 17 + 0.71 x GFR0 (mL/min) + 0.34 x fibrinoid necrosis (%) + 0.33 x segmental crescents (%), (r2 = 0.60; standard deviation = 19 mL/min). Our results were independent of diagnosis, ANCA-specificity, and treatment limb.

CONCLUSIONS

These data suggest that in ANCA-associated glomerulonephritis, GFR0 and predominantly chronic renal lesions are potent predictors of GFR18. Active lesions are associated with renal function recovery and may be reversible. The formula for the estimation of GFR18 shows that a combination of GFR0 and renal histology is a better predictor for GFR18 than GFR0 only.

Long-term renal injury in ANCA-associated vasculitis: an analysis of 31 patients with follow-up biopsies

BACKGROUND

We reported previously that in renal disease in relation to antineutrophil cytoplasm auto-antibodies (ANCA)-associated vasculitis, renal outcome correlates better with the percentage of normal glomeruli than with separate active lesions. This may imply that glomeruli, once affected by necrotizing and crescentic lesions, are irreversibly damaged. We quantified and evaluated the course of renal lesions in the present study.

METHODS

We retrospectively analysed 31 patients with renal disease in relation to ANCA-associated vasculitis, all treated with immunosuppressive drugs. In all patients, a renal biopsy was performed at diagnosis. A follow-up biopsy was performed in all patients on the indication of a suspected renal relapse, after a mean interval of 31 months.

RESULTS

The mean percentage of normal glomeruli in the renal biopsy did not change over time (29% in the initial and 30% in the follow-up biopsy). The mean percentage of glomeruli with crescents, however, significantly decreased from 57 to 30% (P<0.001). The percentage of glomerulosclerosis significantly increased from 12 to 39% (P<0.001). The data were independent of diagnosis, gender, age, time interval between the biopsies, and treatment.

CONCLUSIONS

This is the first study to quantify glomerular changes between two time points in patients with renal vasculitis. Our results suggest that, on average, no new glomeruli are recruited into the active disease process. The sum of the percentage of crescentic and sclerotic glomeruli in the initial biopsies is larger than the percentage of sclerotic glomeruli in the follow-up biopsies. Thus, therapy seems not only to prevent normal glomeruli from being recruited into the active disease process for a certain time, but seems also to allow part of the active lesions to revert into a normal phenotype, although another part of the active lesions will be transformed to a chronic phenotype.

Renal histology in ANCA-associated vasculitis: differences between diagnostic and serologic subgroups

BACKGROUND

Differences in renal histopathology between microscopic polyangiitis (MPA) and Wegener's granulomatosis (WG), and between anti-neutrophil cytoplasm autoantibody (ANCA) test results in patients with ANCA-associated vasculitis may provide insight into the differences in pathogenesis and raise the opportunity of classifying the vasculitides more accurately. The possible differences in histopathology are investigated in this study.

METHODS

We report an analysis of 173 patients with renal disease in microscopic polyangiitis or Wegener's granulomatosis. A total of 173 renal biopsies, performed at diagnosis, were scored by two observers separately, using a previously standardized protocol. Consensus on each biopsy was achieved during a central review.

RESULTS

Normal glomeruli were more common in WG than in MPA (P < 0.001). Glomerulosclerosis was more prominent in MPA than in WG (P=0.003). Interstitial fibrosis (P < 0.001), tubular atrophy (P < 0.001), and tubular casts (P=0.005) were more frequently present and more severe in MPA than in WG. Presence of glomerulosclerosis was more extensive in patients with myeloperoxidase (MPO)-ANCA than with proteinase 3 (PR3)-ANCA (P=0.022). Interstitial fibrosis (P=0.008), tubular necrosis (P=0.030), tubular atrophy (P=0.013), and intra-epithelial infiltrates (P=0.006) were more frequently present and more severe in MPO-ANCA than in PR3-ANCA.

CONCLUSIONS

Glomerulonephritis in relation to MPA has more characteristics of chronic injury at the time of presentation than glomerulonephritis in relation to WG. This difference may be due to a delayed establishment of diagnosis in patients with MPA compared to patients with WG. Both active and chronic lesions are more abundantly present in MPO-ANCA-positive patients than in patients with PR3-ANCA-positivity, which suggests that the pathogenesis of renal disease in these ANCA subsets could be different. Our results also suggest that ANCA test results may be useful in classifying ANCA-associated vasculitides.

Colocalization of ANCA-antigens and fibrinoid necrosis in ANCA-associated vasculitis

A variety of antineutrophil cytoplasmic auto-antibodies (ANCAs) are known to be associated with small vessel vasculitides such as Wegener's granulomatosis and microscopic polyangiitis. To visualize colocalization patterns of the fibrinoid necrotic lesions and ANCA-antigens more accurately, we have developed a double staining technique in which an immunohistochemical staining is followed by a histological staining. Instead of using sequential biopsy slides of histologically and immunohistochemically stained sections, which may lead to an underestimation of the number and size of the lesions, our technique permits the visualization of the colocalized patterns of fibrinoid necrosis with an ANCA-antigen in a single slide. The double staining procedure is presented in this Technical Note.

Graft surveillance: venous pressure, access flow, or the combination?

BACKGROUND

Increased venous pressure (VP) and decreased access flow (Qa) are predictors of dialysis access graft thrombosis. VP is easily obtainable. Qa assessment requires a special device and takes more time. The aims of our randomized multicenter studies were to compare outcome in patients with grafts monitored by VP or Qa (study A) or monitored by VP or the combination of VP and Qa (study B).

METHODS

We performed VP measurements consisting of weekly VP at a pump flow of 200 mL/min (VP200) and the ratio of VP0/MAP. Qa was measured every eight weeks with the Transonic HD01 hemodialysis monitor. Threshold levels for referral for angiography were VP200> 150 mm Hg or VP0/MAP> 0.5 (both at 3 consecutive dialysis sessions) or Qa <600 mL/min. Subsequent therapy consisted of either percutaneous transluminal angioplasty (PTA) or surgery.

RESULTS

Total follow-up was 80.5 patient-years for 125 grafts. The vast majority of a total of 131 positive tests was followed by angiography and corrective intervention. In study A, the rate of thromboses not preceded by a positive test was 0.19 and 0.24 per patient-year (P = NS), and in study B, it was 0.32 versus 0.28 per patient-year (P = NS). Survival curves were not significantly different between the subgroups.

CONCLUSIONS

These data demonstrate that standardized monitoring of either VP or Qa or the combination of both and subsequent corrective intervention can reduce thrombosis rate in grafts to below the recommended quality of care standard (that is, 0.5 per patient-year, NKF-DOQI). These surveillance strategies are equally effective in reducing thrombosis rates.

Distribution of renal lesions in idiopathic systemic vasculitis: A three-dimensional analysis of 87 glomeruli

Extracapillary proliferation and fibrinoid necrosis are the main diagnostic glomerular lesions in renal biopsy specimens of patients with idiopathic systemic vasculitis. Neither the incidence nor the correlation between extracapillary proliferation and fibrinoid necrosis in renal biopsy specimens from patients with systemic vasculitis has been systematically evaluated. By means of a three-dimensional analysis, we made a topographic reconstruction of the distribution of extracapillary proliferation and fibrinoid necrosis in affected glomeruli and tested different biopsy-processing protocols to optimize histopathologic analysis in clinical practice. Paraffin blocks of renal biopsy specimens from six patients diagnosed with systemic vasculitis were completely and serially sectioned in 2-microm thick sections and stained with the Gomori trichrome method. Glomeruli were scored per section for the presence of fibrinoid necrosis and extracapillary proliferation. Subsequently, a three-dimensional reconstruction was obtained for 87 glomeruli. In only one glomerulus did fibrinoid necrosis occur without extracapillary proliferation; in 51%, a combination of the two lesions was found; in 22%, extracapillary proliferation occurred in the absence of fibrinoid necrosis; and 26% did not show either lesion. Using the standard protocol from our department (ie, evaluation of 20 consecutive sections in various stainings), the chance of finding extracapillary proliferation was 100% and that of finding fibrinoid necrosis was 73%. If 5 sections stained with the Gomori trichrome were added, the latter percentage increased to 86%. Using skip-serial sections, even better results (87% to 92%) were obtained, with four skips as the best option (92%). In conclusion, our finding that fibrinoid necrosis rarely occurs in the absence of extracapillary proliferation may imply that both lesions are etiologically related. In addition, our observations indicate that the incidence of fibrinoid necrosis may be underestimated in clinical practice, depending on the number of sections evaluated.

Kidney biopsy as a predictor for renal outcome in ANCA-associated necrotizing glomerulonephritis

BACKGROUND

In kidney biopsies of patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated systemic vasculitis, a variety of histopathological lesions occur, and their relationship to renal outcome is virtually unknown. This multicenter European study reports a clinicopathological analysis of biopsies from 157 patients with systemic vasculitis.

METHODS

The biopsies were evaluated according to a previously standardized scoring protocol. Serum creatinine values were measured at the time of biopsy and one year later. In addition, the lowest creatinine level during follow-up was taken into account as the optimum level of renal function recovery. The clinical prognostic value of the histopathological parameters was analyzed with the Kruskal-Wallis one-way analysis of variance and the Mann-Whitney U-test.

RESULTS

The percentage of normal glomeruli correlated most significantly with renal outcome at all points of measurement (all P < 0.001). Other lesions predicting for renal function were glomerular sclerosis (P < 0.0005 at one year after the biopsy), diffuse interstitial infiltrates (P < 0.0001 at entry, P < 0.0003 at one year), tubular necrosis (P < 0.0025 at entry), and tubular atrophy (P < 0.002 at entry, P < 0.0002 at one year).

CONCLUSION

Traditionally, attention is focused on the extent of active lesions in the renal biopsy in order to determine the severity of renal disease and its implication for renal outcome. Because of their significant impact on renal function, combined with their easy recognition, we recommend the use of the percentage of normal glomeruli in an adequate biopsy in predicting renal function of patients with systemic vasculitis.

International Consensus Statement on Testing and Reporting of Antineutrophil Cytoplasmic Antibodies (ANCA)

Antineutrophil cytoplasmic antibody (ANCA) tests are used to diagnose and monitor inflammatory activity in the primary systemic small vessel vasculitides. ANCA is best demonstrated in these diseases by using a combination of indirect immunofluorescence (IIF) of normal peripheral blood neutrophils and enzyme-linked immunosorbent assays (ELISAs) that detect ANCA specific for proteinase 3 (PR3) or myeloperoxidase (MPO). For ANCA testing in "new" patients, IIF must be performed on all serum samples. Serum samples containing ANCA, any other cytoplasmic fluorescence, or an antinuclear antibody (ANA) that results in homogeneous or peripheral nuclear fluorescence then should be tested in ELISAs for PR3-ANCA and MPO-ANCA. Optimally, ELISAs for PR3-ANCA and MPO-ANCA should be performed on all serum samples. Inclusion of the most recent positive sample in the IIF or ELISA may help demonstrate a change in antibody level. Reports should use recommended terms. Any report of positive neutrophil fluorescence issued before the ELISA results are available should indicate that positive fluorescence alone is not specific for the diagnosis of Wegener granulomatosis or microscopic polyangiitis and that decisions about treatment should not be based solely on the ANCA results.

Evolving concepts about the role of antineutrophil cytoplasm autoantibodies in systemic vasculitides

This review discusses the main issues of antineutrophil cytoplasm autoantibodies (ANCA) that have emerged from the literature. From January 1997 to August 1998, 216 papers were published on ANCA. Two major themes seem to be evolving from these articles. The first theme concerns the specificity and sensitivity of ANCA testing in clinical practice in relation to diagnosing systemic vasculitic syndromes. We focus on immunofluorescence patterns, ANCA antigens, testing methodology, and the (predictive) value of ANCA in clinical practice. Second, there is the unsolved question of how ANCA are etiologically involved in the development of the vasculitic lesion. Ongoing research questions the role of ANCA in stimulating granulocytes, monocytes, and the endothelium.

Diagnostic value of standardized assays for anti-neutrophil cytoplasmic antibodies in idiopathic systemic vasculitis. EC/BCR Project for ANCA Assay Standardization

Anti-neutrophil cytoplasmic antibodies (ANCA) are widely used as diagnostic markers for Wegener's granulomatosis (WG), microscopic polyangiitis (MPA), Churg-Strauss syndrome (CSS) and idiopathic rapidly progressive glomerulonephritis (iRPGN). The objective of this study was to evaluate the diagnostic value of ANCA measurement by the indirect immunofluorescence (IIF) test, and by anti-PR3 and anti-MPO ELISA performed in different locations, in patients with idiopathic small vessel vasculitis. Fourteen centers participated in a standardization study of ANCA assays, and entered a total number of 169 newly diagnosed and 189 historical patients with idiopathic systemic vasculitis or iRPGN. Patients were classified according to a pre-defined diagnostic classification system. Results were compared with those of 184 disease controls and 740 healthy controls. The IIF test was performed according to standard methodology; ELISAs had been standardized among the participants in a previous phase of the study. The sensitivities of assays in patients were as follows. The sensitivity in WG was: cANCA 64%, pANCA 21%, anti-PR3 66%, anti-MPO 24%. In MPA the sensitivity was: cANCA 23%, pANCA 58%, anti-PR3 26%, anti-MPO 58%. Sensitivity in iRPGN was: cANCA 36%, pANCA 45%, anti-PR3 50%, anti-MPO 64%. The specificity of assays (related to disease controls) was: cANCA 95%, pANCA 81%, anti-PR3 87%, anti-MPO 91%. When the results of the IIF test were combined with those of the ELISAs (cANCA/anti-PR3 positive, pANCA/anti-MPO positive), the diagnostic specificity increased to 99%. The sensitivity of the combination of cANCA + anti-PR3 or pANCA + anti-MPO for WG, MPA or iRPGN was 73%, 67% and 82%, respectively. From this study we conclude that the value of the IIF test for ANCA detection can be greatly increased by the addition of a well standardized antigen-specific ELISA. In a significant number of patients with idiopathic small vessel vasculitis, however, the ANCA test results (either in IIF or ELISA) are negative.

Renal granulomas in systemic vasculitis. EC/BCR Project for ANCA-Assay Standardization

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.

Cerebral involvement in two patients with Wegener's granulomatosis

Two cases of cerebral involvement in Wegener's granulomatosis (WG) are described. The course of the disease in both patients was characterized by sudden onset and fatal outcome, despite maximum immunosuppressive therapy. Cerebral involvement is a rare complication of WG. Over the past two decades, only a small number of case-reports appeared of patients with WG who showed this complication. Since the era of cyclophosphamide therapy, it is commonly assumed that cerebral involvement in WG has no influence on patient survival. However, the two patients described here both died shortly after the occurrence of central neurological symptoms.

Wegener's granulomatosis: a meta-analysis of 349 literary case reports

We report the results of a meta-analysis of 349 patients with Wegener's granulomatosis (WG) that were described in the literature from 1979 onward. We describe the patients in terms of diagnosis (granulomas present or absent in biopsy samples from various organs, results of the anti-neutrophil cytoplasmic antibody [ANCA) test) and of the clinical impact of renal involvement. Furthermore, we report the incidence of histopathologic lesions that were found in 134 renal biopsy samples. Before and after the development of the ANCA test, the percentage of patients in whom WG was diagnosed with histologically proven granulomas is the same. However, after 1987 the diagnosis of the group without granulomas is frequently supported by a positive ANCA test result. For the entire group we found that patients without renal involvement (N = 82) were reported to have lower erythrocyte sedimentation rate (ESR), lower white blood cell count (WBC), less anemia, less hypertension, less occurrence of joint symptoms, and less multi-organ involvement than patients with renal involvement (N = 267). The most frequently reported lesion in the renal biopsy samples was extracapillary proliferation (70%), followed by fibrinoid necrosis of the glomerular tuft (54%). Renal granulomas were reported in only 7 biopsy samples.