Little evidence for anti-endothelial cell antibodies in microscopic polyarteritis and Wegener's granulomatosis

We studied sera from patients with vasculitis and controls forthe presence of anti-endothelial cell antibodies (AECA) andcorrelated these with disease type, anti-neutrophil cytoplasmicantibodies (ANCA) and anti-myeloperoxidase (MPO) antibodies.AECA were detected by a cellular ELISA on cultured human umbilicalvein endothelium. AECA were found in the sera of one of 43 patientswith microscopic polyarteritis (2%), five of 27 patients withWegener's granulomatosis (19%), three of 23 patients with anidiopathic glom-erulonephritis (13%), none of eight patientswith rheumatoid arthritis and three of 12 patients with rheumatoidvasculitis (25%). In patients with a vasculitis AECA titreswere higher in sera with a positive ANCA as compared with ANCAnegative sera although the difference was not significant (P= 0.0702) and there was no correlation between AECA and anti-MPOtitres (r = 0.1171 P=0.114). AECA binding was not enhanced followingupregulation of endothelial ICAM-1 and ELAM-1 by TNF. This studyshows that AECA occur infrequently in microscopic polyarteritisand Wegener's granulomatosis, and are not a major antibody systemin these vasculitides.     

Anti-neutrophil cytoplasmic autoantibodies in a child with pauci-immune necrotizing and crescentic glomerulonephritis

We report a case of pauci-immune, necrotizing and crescentic glomerulonephritis in a 10-year-old child initially thought to have Henoch-Schönlein purpura. The diagnosis of a Wegener's granulomatosis-microscopic polyarteritis disorder was made on the basis of clinical presentation and a positive anti-neutrophil cytoplasmic auto-antibody (ANCA). This case illustrates the usefulness of the ANCA in the diagnosis and management of childhood vasculitides.     

Prolonged treatment of refractory Wegener's granulomatosis with 15-deoxyspergualin: an open study in seven patients.

BACKGROUND: A subset of patients with Wegener's granulomatosis does not respond to daily oral cyclophosphamide (CYC) plus corticosteroids or suffers from intolerable side effects. A 6 month course of the immunosuppressant 15-deoxyspergualin (DSG) has previously been employed successfully in these refractory cases. However, there are no reports on long-term treatment with DSG. METHODS: To document the effects of prolonged DSG treatment, this study reports on seven patients suffering refractory Wegener's granulomatosis, who were successfully treated with DSG over an average of 26.5 months (range: 11-55.5 months). RESULTS: Before administration of DSG, patients had experienced an average of 6.6 relapses (range: 3-12) under an average of 5.4 (range: 2-11) different therapeutic approaches, which included CYC in all cases. All suffered active disease when DSG was initiated. Four were unresponsive to CYC and three did not tolerate it. DSG (0.5 mg/kg/day subcutaneous) was given for 2-3 weeks until the leukocyte count dropped to 3000/microl, followed by a rest until a leukocyte count of 4000/microl was reached again. No other immunosuppressants besides corticosteroids were given. All patients showed a long-lasting, favourable response to DSG with complete (n = 5) or partial (n = 2) remission. Only one case relapsed while being treated with DSG. Termination/interruption of DSG was followed by relapse in four of five occasions. Resumption of DSG led to complete remission. Currently, five of the seven patients are still treated with DSG and are in remission. Infections, mainly of the respiratory tract, were observed in five cases and resolved after treatment. One case developed a third-degree heart block that required pacing. CONCLUSIONS: In patients with refractory Wegener's granulomatosis, prolonged treatment with DSG seems safe and successful.     

A case of relapse of C-ANCA-associated glomerulonephritis in post-transplant patients

We experienced a case of relapse of proteinase 3-specific antineutrophil cytoplasmic autoantibody (C-ANCA)-associated rapid progressive glomerulonephritis (RPGN) in a patient after renal transplantation. A 19-yr-old man, who underwent a living donor kidney transplantation, presented a rapid renal function deterioration along with a sign of infection. Initially he was treated as acute rejection, but renal function did not improve. Renal biopsy revealed crescentic glomerulonephritis, and C-ANCA titer was 12 EU/mL, resulting in the diagnosis of C-ANCA-associated RPGN. He was treated with three consecutive methylprednisolone pulses twice in addition to the basal immunosuppressive medications (cyclosporine A and mizoribine), then his renal function improved to normal. Bearing the possibility of recurrence of glomerulonephritis in mind, we re-evaluated the nature and disease course of renal failure of original kidney. He experienced a rapid deterioration of renal function in 1992, and eventually CAPD was started in 1992. His serum in 1992 revealed high titer of C-ANCA (24 EU/mL), and renal biopsy performed in 1992 showed a crescentic glomerulonephritis. Taken together, we diagnosed this event as a relapse of C-ANCA-associated GN. Lessons from our experience are: 1) steroid pulse and high-dose corticosteroid therapy may be useful for the treatment of relapse of C-ANCA-associated GN patients after renal transplantation; 2) the possibility of a relapse of C-ANCA-associated GN following renal transplantation has to be kept in mind, especially when infection precedes the deterioration of allograft kidney function.     

Does the presence of ANCA in patients with ulcerative colitis necessarily imply renal involvement?

BACKGROUND.: ANCA are thought to play a pathogenic role in renal vasculitis.ANCA may also be detected in patients with diseases not usuallyassociated with renal pathology, such as ulcerative colitis.Our study was conducted to determine if the presence of ANCAin patients with ulcerative colitis is associated with renalpathology. METHODS.: Eight ANCA-positive and five ANCA-negative patients with a histologicaland endoscopic diagnosis of active ulcerative colitis were investigated.Repeated complete urinalyses and determination of microalbuminuriaand creatinine clearance were performed. Serum IgG and IgA ANCAwere evaluated in all patients by indirect immunofluorescenceand ELISA, and when detected the antibodies were further characterizedby alpha granules preparation, myeloperoxidase, lactoferrin,and cathepsin G. RESULTS.: In both ANCA-positive and ANCA-negative patients renal functionwas normal or near normal and urinalyses (including microalbuminuria)failed to disclose any abnormalities. ANCA exhibited a perinuclearpattern in all ANCA-positive patients. Interestingly, none ofthe ANCA-positive patients had antibodies to myeloperoxidaseor to alpha granules which are usually found in the sera ofpatients with ANCA-associated vasculitis, and only one had antibodiesto lactoferrin. The ANCA specificity remained undetermined inthe remaining seven patients. At the end of the 1-year observationperiod, all ANCA-positive patients remained ANCA-positive withoutdeveloping symptoms, signs or laboratory abnormalities consistentwith renal involvement. CONCLUSIONS.: Renal damage was not observed in ANCA-positive patients withulcerative colitis even after 1 year of follow-up, suggestingthat the ANCA found in these patients do not share the antigenictargets with the ANCA commonly found in renal vasculitis. Thereforethe potential of ANCA of inducing renal lesions (if any) isdependent on their own antigenic specificity.     

CD4+CD25+ T-cell populations expressing CD134 and GITR are associated with disease activity in patients with Wegener's granulomatosis

Background. An increased CD4⁺ CD25⁺ T-cell population is observedin Wegener's granulomatosis (WG). This T-cell population isnot well characterized yet and their contribution to the diseasepathogenesis remains obscure. Methods. Thirty patients with WG and 18 healthy controls (HC)were included in this study. The disease activity and extensionwere measured by the Birmingham Vasculitis Activity Score (BVAS)and the Disease Extent Index (DEI). Lymphocytes from peripheralblood were analysed by FACS for the expression of CD4, CD25,CD134 and GITR. Cytokine expression in these subsets was assessedtoo. Nasal, lung and renal tissues from WG patients were immunohistochemicallystained for CD3 and CD134. Results. The percentage of CD134⁺ as well as GITR⁺ expressingCD4⁺CD25⁺ lymphocytes was increased in patients as comparedto HC (37 ± 12% versus 27 ± 8%, P = 0.005; 18± 9% versus 11 ± 6%, P = 0.003). The expressionof CD134 and GITR showed a significant correlation with diseaseactivity (r = 0.5, P = 0.009; r = 0.55, P = 0.001). Most ofthese displayed the phenotype of effector memory T-cells (94± 4% and 91 ± 6%). CD134 T-cells were found intissues affected by WG. Conclusions. CD4⁺CD25⁺ effector memory T-cells expressing CD134and GITR seem to play a role in disease mechanisms, as suggestedby their close association with disease activity and their participationin inflammatory process.     

Proteinase 3-ANCA Vasculitis versus Myeloperoxidase-ANCA Vasculitis

In patients with GN or vasculitis, ANCAs are directed against proteinase 3 (PR3) or myeloperoxidase (MPO). The differences between PR3-ANCA-associated vasculitis (AAV) and MPO-AAV described in the past have been supplemented during the last decade. In this review, we discuss the differences between these two small-vessel vasculitides, focusing especially on possible etiologic and pathophysiologic differences. PR3-AAV is more common in northern parts of the world, whereas MPO-AAV is more common in southern regions of Europe, Asia, and the Pacific, with the exception of New Zealand and Australia. A genetic contribution has been extensively studied, and there is a high prevalence of the HLA-DPB1*04:01 allele in patients with PR3-AAV as opposed to patients with MPO-AAV and/or healthy controls. Histologically, MPO-AAV and PR3-AAV are similar but show qualitative differences when analyzed carefully. Clinically, both serotypes are difficult to distinguish, but quantitative differences are present. More organs are affected in PR3-AAV, whereas renal limited vasculitis occurs more often in patients with MPO-AAV. For future clinical trials, we advocate classifying patients by ANCA serotype as opposed to the traditional disease type classification.     

Diagnostic significance and antigen specificity of antineutrophil cytoplasmic antibodies in renal diseases. A prospective multicentre study

In a prospective multicentre study on the clinical significanceof ANCA in renal diseases, sera from 920 patients with rapidlyprogressive renal failure and/or renal disease in associationwith extrarenal signs suggestive of a systemic vasculitis weretested for the presence of ANCA by indirect immunofluorescence(IIF) and ELISA. 193 of 920 cases (20.9%) were positive by IIFand 180 (19.5%) by ELISA, using a ‘crude’ cytoplasmicextract as substrate. The sensitivity and specificity of IIFfor ‘pauci-immune’ crescentic necrotizing GN (CNGN),in association or not with systemic vasculitis, was 87.5 and95.6% respectively. The IIF pattern and antigen specificity (alpha granules andMPO) correlated well with the clinical features: a cANCA pattern(alpha granules) was associated with ENT involvement (probableWegener's granulomatosis); a pANCA pattern (MPO) with ‘idiopathic’CNGN and small-vessel vasculitis without respiratory tract disease(microscopic polyarteritis); patients with a pulmonary-renalsyndrome had either c or pANCA in a similar proportion. Our study confirms a high sensitivity and specificity of ANCAfor patients with CNGN. ANCA should be considered an important diagnostic test in patientswith renal diseases, especially in the presence of rapidly progressiverenal failure.     

Treatment of small vessel vasculitis affecting the kidneys

Summary: Treatment of vasculitis can be divided into two phases: (i) an induction phase to achieve remission, abate destructive inflammation and minimize scarring; and (ii) the maintenance phase to sustain patients in remission with minimal treatment-related side-effects. A combination of corticosteroids and cytotoxic agents is commonly used as induction therapy. the dose and route of administration of corticosteroids have not been studied adequately, but intravenous (i.v.) bolus doses of methyiprednisolone are often administered to patients with severe disease. It has the advantage of fewer side-effects compared to prolonged high dose oral corticosteroids, and the immediate immuno-modulatory effects of the steroid boluses may confer additional therapeutic benefits. It is the general impression that cyclophosphamide is more effective than azathioprine in the acute phase of patients with severe disease. the use of cyclophosphamide by i.v. pulse rather than orally is contentious, and some recent studies have demonstrated its failure to induce sustained remission. Azathioprine with low dose corticosteroids is often employed as long-term maintenance immunosuppression, although low dose cyclophosphamide has also been used for such purpose, which should be withdrawn after 1 year of remission because of its potential side-effects. Clinical and serologic parameters are useful monitors during maintenance therapy. Although serial levels of anti neutrophil cytoplasm antibodies (ANCA) correlate with disease activity, some patients remain well despite positive or increasing levels of ANCA. Consequently, whether immunosuppressive therapy should be esclated based on increasing ANCA Levels along remains controversal.     

Urine IgM excretion predicts outcome in ANCA-associated renal vasculitis.

BACKGROUND: Renal function at diagnosis is a strong predictor not only of renal survival but also of patient survival of those with anti-neutrophil cytoplasmic antibody (ANCA)-associated small vessel vasculitis (ASVV). Apart from the renal function at diagnosis, there are no other established risk factors for renal outcome in ASVV. We have previously reported that in other forms of glomerular diseases, an increased urine excretion of IgM is an early marker of poor renal outcome. METHODS: In this single-centre observational study, the prognostic significance of urine IgM excretion and other selected prognostic markers was studied in 83 consecutive patients (49 males, 34 females) with ASVV with renal involvement. RESULTS: Patient survival at 1 and 5 years was 93 and 77%, respectively, and the corresponding figures for renal survival censored for death were 84 and 76%. Univariate analysis indicated that patient survival was inversely associated with age, male sex, serum creatinine, low serum albumin and high urine IgM excretion. Renal survival was inversely associated with serum creatinine, albuminuria and urine IgM. Multivariate analysis determined that only old age and high urine IgM excretion were independent predictors of patient survival [odds ratio (OR) = 11.2 and 4.4, respectively, P<0.01]. Urine excretion of IgM was the only independent predictor of end-stage renal disease (OR = 19.8, P = 0.004). Overall, 35% of the patients reached the composite end-point of either death or renal replacement therapy. Urine IgM excretion was the most potent single predictor of such an outcome (OR = 7.7, P = 0.000). CONCLUSION: The occurrence of an increased amount of IgM in urine at presentation is a strong marker of poor prognosis for patients with ANCA-associated renal vasculitis.     

The role of flow cytometric ANCA detection in screening for acute pauci-immune crescentic glomerulonephritis.

BACKGROUND: Most cases of pauci-immune crescentic glomerulonephritis (PICGN) are associated with serum anti-neutrophil cytoplasmic antibodies (ANCA). This article studied the sensitivity and specificity of serum ANCA, determined by flow cytometry and indirect immunofluorescence (IIF), to identify patients with acute PICGN. METHODS: 577 adults presenting for first biopsy of their native kidneys with serum taken for ANCA (flow cytometry and IIF) determination were studied. A positive ANCA was defined using a flow cytometric ANCA assay as a screening test, followed by a slide-based indirect IIF technique. Pathological confirmation of acute PICGN was used to assess the sensitivity and specificity of this combined approach and its positive predictive value (PPV) and negative predictive value (NPV) in patients presenting for renal biopsy due to abnormal urinary sediment. RESULTS: Forty-nine patients were found to have acute PICGN on renal biopsy. Of these 47 were ANCA positive (sensitivity 95.9%). Overall 93 of the renal biopsy patients were ANCA positive, (specificity 91.3%). A further seven patients (two ANCA positive) had advanced sclerosing disease consistent with PICGN but without evidence of current disease activity. The PPV and NPV of ANCA, assessed by flow cytometry and slide IIF, in predicting that patients presenting with undifferentiated renal disease would have acute PICGN was 50.5 and 99.8%, respectively. CONCLUSIONS: Flow cytometric screening of serum for ANCA in patients undergoing renal biopsy has a high NPV for determining those with acute PICGN. It may provide a rapid, simple screening test for this lesion in laboratories using diagnostic flow cytometry and may complement IIF/ELISA in evaluating ANCA positive patients.     

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.     

Propylthiouracil-Induced Vasculitis Associated with ANCA: A Case Report

Propylthiouracil is a drug used in the treatment of hyperthyroidism for more than 60 years. Adverse side effects are seen in 1–5% of patients. Renal complications of the drug including glomerulonephritis and vasculitis are rarely seen. Cases of propylthiouracil-induced rapidly progressive glomerulonephritis and vasculitis are reported in association with antineutrophil cytoplasmic autoantibodies. Here we report a case of positive antineutrophil cytoplasmic autoantibodies rapidly progressive glomerulonephritis (RPGN) associated with propylthiouracil treatment.     

No association of G-463A myeloperoxidase gene polymorphism with MPO-ANCA-associated vasculitis.

BACKGROUND: The activation of neutrophils and monocytes by ANCA, resulting in the release of reactive oxygen species and proteases like myeloperoxidase (MPO), is essential to the pathogenesis of ANCA-associated vasculitis. As the A allele of the G-463A MPO gene polymorphism is associated with diminished activity of MPO, it is conceivable that the presence of this allele protects against MPO-ANCA-associated vasculitis. METHODS: Allelic frequencies of the G-463A polymorphism were studied in 119 ANCA-associated vasculitis patients, 48 with MPO-ANCA and 71 with proteinase 3 (PR3)-ANCA. RESULTS: Allelic frequencies of MPO G-463A promoter polymorphism did not differ between MPO-ANCA- and PR3-ANCA-associated vasculitis patients. Moreover, allelic distribution was similar to that of the normal population. CONCLUSIONS: The data suggest that G-463A polymorphism does not seem to contribute to either MPO-ANCA- or PR3-ANCA-associated vasculitis formation.