Clinical outcomes of remission induction therapy for severe antineutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To evaluate the reasons that complete remission is not achieved or maintained with original treatment in some patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) treated with rituximab (RTX) or with cyclophosphamide/azathioprine (CYC/AZA).

METHODS

The Rituximab in AAV trial was a randomized, double-blind, placebo-controlled trial comparing the rate of remission induction among patients treated with RTX (n = 99) and patients treated with CYC followed by AZA (n = 98). Glucocorticoids were tapered over a period of 5 months. The primary outcome measure was lack of disease activity without glucocorticoid treatment at 6 months. To determine the most important reason for failure to achieve the primary outcome, 7 hierarchical categories of reasons were defined retrospectively (uncontrolled disease, adverse event leading to therapy discontinuation, severe flare, limited flare, Birmingham Vasculitis Activity Score for Wegener's Granulomatosis >0, prednisone treatment at any dosage, and other).

RESULTS

Although remission (lack of disease activity) was achieved in 170 of the 197 patients (86%) in the first 6 months, the primary outcome measure was not achieved in 42%. There were 3 deaths. Twenty-four percent of the patients failed to achieve the primary end point due to active disease: 10 (5%) experienced uncontrolled disease in the first month and 37 (19%) experienced flares after initial improvement. In the majority of such patients, treatment with blinded crossover or according to best medical judgment led to disease control. Ninety-one percent of patients who had uncontrolled disease or experienced a severe flare had proteinase 3 (PR3)-ANCA. When patients with uncontrolled disease were excluded from analysis, those who were PR3-ANCA positive were found to experience fewer flares when treated with RTX compared to CYC/AZA (8 of 59 [14%] versus 20 of 62 [32%]; P = 0.02). Neither ANCA titers nor B cell counts predicted disease flare.

CONCLUSION

Current treatment regimens are largely successful in controlling AAV, but in approximately one-fourth of patients, active disease persists or recurs in the first 6 months despite treatment. PR3-ANCA positivity is a risk factor for recurrence or persistence of severe disease. ANCA titers and B cell detectability are poor predictors of both disease relapse and disease quiescence in the first 6 months.

Daily physical activity in ankylosing spondylitis: validity and reliability of the IPAQ and SQUASH and the relation with clinical assessments

Introduction

The aim of this study was to investigate the construct validity and test-retest reliability of the International Physical Activity Questionnaire (IPAQ; long form) and the Short QUestionnaire to Assess Health-enhancing physical activity (SQUASH) and to investigate the relation between daily physical activity and clinical assessments in patients with ankylosing spondylitis (AS).

Methods

For validity, the self-report questionnaires IPAQ and SQUASH were compared with daily physical activity assessed with the ActiGraph accelerometer during 7 consecutive days in 63 AS outpatients. For reliability, the IPAQ and SQUASH were administered twice approximately 1 week apart in 52 AS outpatients. In all 115 patients, clinical assessments were performed at the outpatient clinic.

Results

IPAQ and SQUASH total scores correlated significantly with accelerometer outcome: ρ = 0.38 and r = 0.35, respectively. Intraclass correlation coefficients between first and second assessments of the IPAQ and SQUASH were 0.83 and 0.89, respectively. Bland-Altman analyses showed no systemic bias, but in particular for the IPAQ the 95% limits of agreement were wide. Daily physical activity assessed by accelerometer, IPAQ, and SQUASH correlated significantly with disease activity, physical activity, and quality of life. A relation with spinal mobility was found only for the accelerometer and SQUASH. The direction of these correlations indicates that higher daily physical activity is related to lower disease activity and better physical function, spinal mobility and quality of life.

Conclusions

Both physical activity questionnaires showed modest construct validity. The SQUASH showed good test-retest reliability, superior to the IPAQ. These results indicate that the SQUASH is more suitable than the IPAQ to assess daily physical activity in AS population studies. However, it is desirable to add questions on AS-specific physical activity. Further studies are needed to investigate the causality of the relation between daily physical activity and clinical assessments.

Efficacy of remission-induction regimens for ANCA-associated vasculitis

BACKGROUND

The 18-month efficacy of a single course of rituximab as compared with conventional immunosuppression with cyclophosphamide followed by azathioprine in patients with severe (organ-threatening) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is unknown.

METHODS

In a multicenter, randomized, double-blind, double-dummy, noninferiority trial, we compared rituximab (375 mg per square meter of body-surface area administered once a week for 4 weeks) followed by placebo with cyclophosphamide administered for 3 to 6 months followed by azathioprine for 12 to 15 months. The primary outcome measure was complete remission of disease by 6 months, with the remission maintained through 18 months.

RESULTS

A total of 197 patients were enrolled. As reported previously, 64% of the patients in the rituximab group, as compared with 53% of the patients in the cyclophosphamide-azathioprine group, had a complete remission by 6 months. At 12 and 18 months, 48% and 39%, respectively, of the patients in the rituximab group had maintained the complete remissions, as compared with 39% and 33%, respectively, in the comparison group. Rituximab met the prespecified criteria for noninferiority (P<0.001, with a noninferiority margin of 20%). There was no significant difference between the groups in any efficacy measure, including the duration of complete remission and the frequency or severity of relapses. Among the 101 patients who had relapsing disease at baseline, rituximab was superior to conventional immunosuppression at 6 months (P=0.01) and at 12 months (P=0.009) but not at 18 months (P=0.06), at which time most patients in the rituximab group had reconstituted B cells. There was no significant between-group difference in adverse events.

CONCLUSIONS

In patients with severe ANCA-associated vasculitis, a single course of rituximab was as effective as continuous conventional immunosuppressive therapy for the induction and maintenance of remissions over the course of 18 months. (Funded by the National Institute of Allergy and Infectious Diseases and others; RAVE ClinicalTrials.gov number, NCT00104299.)

Treatment of ANCA-associated vasculitis, where to go?

The introduction of (oral) cyclophosphamide (CYC) in the treatment of ANCA-associated vasculitides (AAV) has strongly improved prognosis but the side effects of long-term CYC treatment are serious. A number of recent randomized controlled studies have shown that the cumulative dose of CYC can be strongly reduced in the treatment of AAV or even reduced to zero. Maintenance treatment can be performed with azathioprine (AZA), or methotrexate (MTX) in case of intolerance, although the intensity and duration of maintenance treatment is still under discussion. More insight into the mechanisms involved in relapsing disease might allow individualized treatment. Induction of remission can be achieved in cases of mild disease expression with MTX but requires maintenance treatment to prevent relapses. Generalized disease can be treated with pulses of i.v. CYC or, possibly, with MMF. However, recent studies demonstrate the efficacy of RTX in inducing remission without the concomitant use of immunosuppressives. Corticosteroids are part of treatment in all regimens but the intensity and duration of steroid treatment is still being discussed. In life-threatening disease, the adjunctive efficacy of plasma exchange has been demonstrated and its usefulness in less severe disease is under investigation. Taken together, there are, indeed, alternatives for CYC in AAV.

High mobility group box1 (HMGB1) in relation to cutaneous inflammation in systemic lupus erythematosus (SLE)

Summary

Photosensitivity is characteristic of systemic lupus erythematosus (SLE). Upon ultraviolet B (UVB) exposure, patients develop inflammatory skin lesions in the vicinity of sunburn cells (SBCs). High mobility group box 1 (HMGB1) is released from apoptotic and activated cells and exerts inflammatory actions through ligation to its receptors.

Methods

Eleven SLE patients and 10 healthy controls (HCs) were exposed to UVB. Skin biopsies were taken before and at one, three and 10 days after irradiation. Sections were stained for SBC, HMGB1, CD3, CD68, interferon-induced protein MxA and cleaved caspase 3. In vitro experiments with UVB-irradiated keratinocytes were also performed. Higher numbers of cells that had released HMGB1 were seen in the skin of SLE patients compared to HCs before and after irradiation. HMGB1-negative nuclei correlated with the presence of SBCs, and with the number of cleaved caspase 3 positive cells in lupus skin.

Results

HMGB1 release is increased in the skin of SLE patients compared to HCs. Upon UVB exposure, HMGB1 release further increases in SLE patients and is related to the number of apoptotic cells. Our data suggest that HMGB1, probably released from apoptotic keratinocytes, contributes to the development of inflammatory lesions in the skin of SLE patients upon UVB exposure.

Urinary CD8+ T-cell counts discriminate between active and inactive lupus nephritis

Introduction

Lupus nephritis (LN) is a severe and frequent manifestation of systemic lupus erythematosus (SLE). Early detection of initial renal manifestations and relapses during follow-up is pivotal to prevent loss of renal function. Apart from renal biopsies, current urinary and serological diagnostic tests fail to accurately demonstrate the presence of active LN. Previously, we demonstrated that effector memory T-cells (CD45RO⁺CCR7^-;T_EM) migrate into the urine during active LN. The objective of this study was to assess the diagnostic value of urinary T-cells in comparison with traditional markers of active LN.

Methods

T-cells in the urine during active LN and remission were investigated. Twenty-two, in most cases biopsy-proven, active LN patients and 24 SLE patients without active LN were enrolled and serial measurements were performed in 16 patients.

Results

Analysis of the urinary sediment in active renal disease showed an increased number of CD8⁺ T-cells and absence of these cells during remission. Enumerating T-cell counts in LN patients with a history of renal involvement was a superior marker of active LN in comparison to traditional markers, such as proteinuria and s-creatinine.

Conclusions

In conclusion, urinary T-cells, in particular CD8⁺ T cells, are a promising marker to assess renal activity in LN patients, in particular in those with prior renal involvement.

Could we abandon cyclophosphamide in systemic vasculitis and lupus nephritis?

Cyclophosphamide has greatly improved prognosis in anti-neutrophil cytoplasmic autoantibody-associated vasculitis (AAV) and proliferative lupus nephritis (LN). However, the side effects of long-term cyclophosphamide treatment are considerable prompting a search for alternatives to cyclophosphamide. For maintenance treatment in AAV, azathioprine is the preferred drug with methotrexate as an alternative in the case of intolerance to azathioprine. Data on mycophenolate mofetil (MMF) for the induction of remission in AAV are being awaited, but rituximab appears as effective as cyclophosphamide in newly diagnosed patients with AAV, and is probably even better for relapsing patients, while the possibility of maintenance treatment with intermittent low-dose infusions of rituximab is being explored. In LN, low-dose intravenous cyclophosphamide is as effective as high-dose cyclophosphamide for the induction of remission, with azathioprine being used for maintenance treatment. MMF can be used in the case of intolerance to cyclophosphamide and might be the first choice in black and Hispanic patients. In the case of intolerance to both cyclophosphamide and MMF, azathioprine with pulses of methylprednisolone can be used. Here, the role of rituximab has not been established. In conclusion, alternatives are available for cyclophosphamide both in AAV and proliferative LN.

Systems analysis of primary Sjögren's syndrome pathogenesis in salivary glands identifies shared pathways in human and a mouse model

Introduction

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease with complex etiopathogenesis. Despite extensive studies to understand the disease process utilizing human and mouse models, the intersection between these species remains elusive. To address this gap, we utilized a novel systems biology approach to identify disease-related gene modules and signaling pathways that overlap between humans and mice.

Methods

Parotid gland tissues were harvested from 24 pSS and 16 non-pSS sicca patients and 25 controls. For mouse studies, salivary glands were harvested from C57BL/6.NOD-Aec1Aec2 mice at various times during development of pSS-like disease. RNA was analyzed with Affymetrix HG U133+2.0 arrays for human samples and with MOE430+2.0 arrays for mouse samples. The images were processed with Affymetrix software. Weighted-gene co-expression network analysis was used to identify disease-related and functional pathways.

Results

Nineteen co-expression modules were identified in human parotid tissue, of which four were significantly upregulated and three were downregulated in pSS patients compared with non-pSS sicca patients and controls. Notably, one of the human disease-related modules was highly preserved in the mouse model, and was enriched with genes involved in immune and inflammatory responses. Further comparison between these two species led to the identification of genes associated with leukocyte recruitment and germinal center formation.

Conclusion

Our systems biology analysis of genome-wide expression data from salivary gland tissue of pSS patients and from a pSS mouse model identified common dysregulated biological pathways and molecular targets underlying critical molecular alterations in pSS pathogenesis.

Joint European League Against Rheumatism and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis

OBJECTIVES

To develop recommendations for the management of adult and paediatric lupus nephritis (LN).

METHODS

The available evidence was systematically reviewed using the PubMed database. A modified Delphi method was used to compile questions, elicit expert opinions and reach consensus.

RESULTS

Immunosuppressive treatment should be guided by renal biopsy, and aiming for complete renal response (proteinuria <0.5 g/24 h with normal or near-normal renal function). Hydroxychloroquine is recommended for all patients with LN. Because of a more favourable efficacy/toxicity ratio, as initial treatment for patients with class III-IV(A) or (A/C) (±V) LN according to the International Society of Nephrology/Renal Pathology Society 2003 classification, mycophenolic acid (MPA) or low-dose intravenous cyclophosphamide (CY) in combination with glucocorticoids is recommended. In patients with adverse clinical or histological features, CY can be prescribed at higher doses, while azathioprine is an alternative for milder cases. For pure class V LN with nephrotic-range proteinuria, MPA in combination with oral glucocorticoids is recommended as initial treatment. In patients improving after initial treatment, subsequent immunosuppression with MPA or azathioprine is recommended for at least 3 years; in such cases, initial treatment with MPA should be followed by MPA. For MPA or CY failures, switching to the other agent, or to rituximab, is the suggested course of action. In anticipation of pregnancy, patients should be switched to appropriate medications without reducing the intensity of treatment. There is no evidence to suggest that management of LN should differ in children versus adults.

CONCLUSIONS

Recommendations for the management of LN were developed using an evidence-based approach followed by expert consensus.

Persistence of immunoglobulin-producing cells in parotid salivary glands of patients with primary Sjögren's syndrome after B cell depletion therapy

Objectives

To assess the persistence of immunoglobulin-producing cell populations in the parotid salivary glands of patients with primary Sjögren's syndrome (pSS) after B cell depletion therapy with rituximab.

Methods

Thirteen patients with pSS and four control patients were included in this study. Patients with pSS were treated with rituximab or placebo. Sequence analysis was carried out on IgA- and IgG-encoding transcripts extracted from parotid salivary gland biopsy specimens taken before treatment and at 12–16 and 36–52 weeks after treatment.

Results

At baseline, many clonally related sequences were seen in patients with pSS. The number of clonal expansions was significantly higher in patients with pSS than in control patients. Clonal expansions were composed of IgA- and/or IgG-expressing cells. Rituximab did not significantly alter the degree of clonal expansions. Groups of clonally related cells had members which were shared between biopsy specimens taken before and after treatment. Mutation frequencies of immunoglobulin sequences from clonally related cells in patients with pSS were higher after treatment.

Conclusions

Rituximab treatment does not alter the characteristic features of increased clonal expansions seen in the parotid salivary glands of patients with pSS. The presence of clonally related immunoglobulin-producing cells before and after rituximab treatment strongly suggests that immunoglobulin-producing cells persist in salivary glands of patients with pSS despite B cell depletion. The presence of mixed isotype expression within groups of clonally related cells indicates local class switching in salivary glands of patients with pSS. Persistent immunoglobulin-producing cells may underlie disease relapse after treatment.

Receptor for advanced glycation end products (RAGE) polymorphisms are associated with systemic lupus erythematosus and disease severity in lupus nephritis

OBJECTIVE

Interaction of advanced glycation end products (AGEs) with their receptors (RAGE) plays an important role in inflammation in auto-immune diseases. Several functional polymorphisms of RAGE have been described. In this study we analysed the role of RAGE polymorphisms in disease susceptibility for systemic lupus erythematosus (SLE). In addition, we investigated whether these polymorphisms in SLE are associated with serum levels of soluble RAGE (sRAGE), renal involvement (lupus nephritis (LN)) and its outcome.

METHODS

For this cross-sectional study DNA samples of 97 SLE patients, 114 LN patients and 429 healthy controls (HC) were genotyped for four RAGE polymorphisms: -429 T/C, -374 T/A, 2184 A/G and Gly82Ser. Differences in genotype frequencies and allele frequencies were tested between patients and HCs. In SLE patients, sRAGE was measured by enzyme-linked immunosorbent assay (ELISA). In addition, association of genotypes with sRAGE and disease severity in LN was analysed.

RESULTS

The C allele of -429 T/C, the T allele of -374 T/A and the G allele of 2184 A/G were significantly more prevalent in SLE and LN compared with HC. In LN, the C allele of RAGE -429 T/C, the A allele of -374 T/A and the G allele of RAGE 2184 A/G polymorphism were significantly associated with more proteinuria and worse renal function during the first two years of treatment. No association of genotype with sRAGE was found.

CONCLUSION

RAGE polymorphisms are associated with susceptibility to SLE and LN. In addition, some of these polymorphisms are likely to be associated with disease severity and initial response to treatment in LN.

Pathogenesis of ANCA-associated vasculitis, an update

Clinical observations, including a report of neonatal vasculitis occurring in a child born from a mother with anti-neutrophil cytoplasmic antibody directed to myeloperoxidase (MPO-ANCA)-associated vasculitis, suggest a pathogenic role for ANCA. Such a role is supported by in vitro experimental data showing that ANCA can activate primed neutrophils to the production of reactive oxygen species and lytic enzymes resulting in lysis of endothelial cells. An interplay between neutrophils, the alternative pathway of complement, and MPO-ANCA resulting in systemic vasculitis including necrotizing glomerulonephritis has clearly been demonstrated in animal models. An in vivo pathogenic role of ANCA directed to proteinase 3 (PR3-ANCA) has, however, not been substantiated. In PR3-ANCA-associated vasculitis, granulomatous inflammation points to involvement of cell-mediated immunity. In vitro studies, indeed, suggest that PR3-specific Th17 CD4-positive lymphocytes are operative in lesion development. The triggering role of microbial factors is becoming more clear. In particular Staphylococcus aureus carriage and infection with Gram-negative bacteria could contribute to induction and persistence of ANCA-associated vasculitis (AAV). Insight into the pathogenic pathways involved in AAV have opened and will further open new ways to targeted treatment.

Circulating markers of vascular injury and angiogenesis in antineutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To identify biomarkers that distinguish between active antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and remission in a manner superior or complementary to established markers of systemic inflammation.

METHODS

Markers of vascular injury and angiogenesis were measured before and after treatment in a large clinical trial in AAV: 163 subjects enrolled in the Rituximab in ANCA-Associated Vasculitis trial were screened for the present study. Serum levels of E-selectin, intercellular adhesion molecule 3 matrix metalloproteinase protein 1 (MMP-1), MMP-3, MMP-9, P-selectin, thrombomodulin, and vascular endothelial growth factor were measured at study screening (time of active disease) and at month 6. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels had been measured at the time of the clinical visit. The primary outcome measure was the difference in marker level between screening and month 6 among patients whose disease was in remission (Birmingham Vasculitis Activity Score for Wegener's granulomatosis [BVAS/WG] score of 0) at month 6.

RESULTS

All patients had severe active vasculitis at screening (mean ± SD BVAS/WG score 8.6 ± 3.2). Among the 123 patients whose disease was clinically in remission at month 6, levels of all markers except E-selectin showed significant declines. MMP-3 levels were also higher among the 23 patients with active disease at month 6 than among the 123 patients whose disease was in remission. MMP-3 levels correlated weakly with ESR and CRP levels.

CONCLUSION

Many markers of vascular injury and angiogenesis are elevated in severe active AAV and decline with treatment, but MMP-3 appears to distinguish active AAV from remission better than the other markers studied. Further study of MMP-3 is warranted to determine its clinical utility in combination with conventional markers of inflammation and ANCA titers.

Advanced glycation endproducts are increased in rheumatoid arthritis patients with controlled disease

Introduction

Advanced glycation end products (AGEs) are produced and can accumulate during chronic inflammation, as might be present in patients with rheumatoid arthritis (RA). AGEs are involved in the development of cardiovascular disease. The aim of this study is to evaluate whether AGEs are increased in patients with long-standing RA and whether AGE accumulation is related to disease activity, disease severity and measures of (premature) atherosclerosis, such as endothelial activation, endothelial dysfunction and intima media thickness (IMT).

Methods

In a cross-sectional study, 49 consecutive RA patients with longstanding disease (median disease duration of 12.3 years (range 9.3 to 15.1)), receiving standard of care, were included and compared with 49 age- and sex-matched healthy controls (HC). AGEs were determined by skin autofluorescence. Disease activity was evaluated by the Disease Activity Score of 28 joints (DAS-28) score and joint damage by modified Sharp-v.d. Heijde score. Endothelial activation (soluble vascular cellular adhesion molecule-1) sVCAM-1, von Willebrand factor (vWF), thrombomodulin), endothelial dysfunction (determined by small artery elasticity (SAE)) and IMT were measured and related to AGE accumulation.

Results

AGEs were increased in RA patients (median 2.4 arbitrary units (a.u.), range 1.6 to 4.2) compared to HC (2.2, 1.3 to 3.8). RA patients had a DAS-28 score of 2.9 (0.8 to 6.9) and a modified Sharp-v.d. Heijde score of 19 (0 to 103). sVCAM-1 and vWF levels were higher in RA patients. SAE was significantly decreased in RA (3.9 ml/mmHg (1.4 to 12.2) vs. 6.1 in HC (1.7 to 12.9). IMT did not differ between the two groups. Combining both groups' AGEs correlated with vWF, sVCAM-1 and IMT, and was inversely related to SAE. In RA, AGEs had an inverse relation with SAE, but did not relate to disease activity or radiological damage. In multivariate analysis for both groups, smoking, glucose levels, vWF, SAE and male gender were significantly related to the formation of AGEs.

Conclusions

AGEs were increased in RA patients with long-standing disease and without signs of premature atherosclerosis. AGEs were related to endothelial activation and endothelial dysfunction. This supports the hypothesis that in RA AGEs may be an early marker of cardiovascular disease.

Decreased CXCR1 and CXCR2 expression on neutrophils in anti-neutrophil cytoplasmic autoantibody-associated vasculitides potentially increases neutrophil adhesion and impairs migration

INTRODUCTION

In anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides (AAV), persistent inflammation within the vessel wall suggests perturbed neutrophil trafficking leading to accumulation of activated neutrophils in the microvascular compartment. CXCR1 and CXCR2, being major chemokine receptors on neutrophils, are largely responsible for neutrophil recruitment. We speculate that down-regulated expression of CXCR1/2 retains neutrophils within the vessel wall and, consequently, leads to vessel damage.

METHODS

Membrane expression of CXCR1/2 on neutrophils was assessed by flow cytometry. Serum levels of interleukin-8 (IL-8), tumor necrosis factor alpha (TNF-α), angiopoietin 1 and angiopoietin 2 from quiescent and active AAV patients and healthy controls (HC) were quantified by ELISA. Adhesion and transendothelial migration of isolated neutrophils were analyzed using adhesion assays and Transwell systems, respectively.

RESULTS

Expression of CXCR1 and CXCR2 on neutrophils was significantly decreased in AAV patients compared to HC. Levels of IL-8, which, as TNFα, dose-dependently down-regulated CXCR1 and CXCR2 expression on neutrophils in vitro, were significantly increased in the serum of patients with active AAV and correlated negatively with CXCR1/CXCR2 expression on neutrophils, even in quiescent patients. Blocking CXCR1 and CXCR2 with repertaxin increased neutrophil adhesion and inhibited migration through a glomerular endothelial cell layer.

CONCLUSIONS

Expression of CXCR1 and CXCR2 is decreased in AAV, potentially induced by circulating proinflammatory cytokines such as IL-8. Down-regulation of these chemokine receptors could increase neutrophil adhesion and impair its migration through the glomerular endothelium, contributing to neutrophil accumulation and, in concert with ANCA, persistent inflammation within the vessel wall.

Re-evaluation of the histopathologic classification of ANCA-associated glomerulonephritis: a study of 121 patients in a single center

BACKGROUND

The recently published histopathologic classification of antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis might greatly aid in the prognostication of patients at the time of diagnosis. This study aims to re-evaluate the new classification for its prognostic capacity in an independent Chinese series.

METHODS

One hundred and twenty-one consecutive patients with ANCA-associated glomerulonephritis, diagnosed in our center from 1997 to 2010, were included in this retrospective study. The renal specimens were reviewed according to the proposed histopathologic classification. The predictive value of the classification for renal outcome and renal response to treatment was analyzed.

RESULTS

Thirty-three (27.3%), 24 (19.8%), 53 (43.8%) and 11 (9.1%) patients were classified as focal, mixed, crescentic and sclerotic ANCA-associated glomerulonephritis, respectively. The renal biopsy categories correlated with initial serum creatinine and the renal response to treatment (P < 0.001, P < 0.01, respectively). The probability of progressing to end-stage renal disease (ESRD) increased with ascending categories of focal, mixed, crescentic and sclerotic glomerulonephritis (P < 0.01). The patients with focal, mixed and crescentic ANCA-associated glomerulonephritis were all at decreased risk for developing ESRD compared with the patients with in the sclerotic category (P < 0.05).

CONCLUSIONS

The proposed classification system was re-evaluated for the first time in a relatively large and independent series of patients. This system reflects the severity of the initial renal impairment and can predict, at least to some extent, the renal response to treatment. More importantly, it can independently predict renal outcome, in particular development of ESRD.

Increase in IL-21 producing T-cells in patients with systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is an autoimmune disease accompanied by a disturbed T-cell balance skewed towards effector T-cells, in particular Th17-cells. The novel cytokine interleukin-21 (IL-21) is suggested to be crucial for triggering T-cell responses towards IL-17 producing cells. Thus, we aimed to investigate the ability of T-cells to produce IL-21 and IL-17 in SLE patients.

METHODS

Peripheral blood of 34 SLE patients and 18 healthy controls (HC) was stimulated with phorbol myristate acetate (PMA) and calcium ionophore (Ca-Io). Percentages of IL-21- and IL-17A expressing T-cells were analysed by flow cytometry. The expression levels of the transcription factors B-cell lymphoma-6 (BCL-6) and factors retinoid-related orphan receptor (ROR-γt) were assessed in T-cells by real-time RT-PCR and flow cytometry. Additionally, IL-21 receptor (IL-21R) expression on B- and T-cells of patients and HC was analyzed.

RESULTS

Significantly increased percentages of IL-21 expressing CD4+ T-cells and CD8+ T-cells were found in SLE patients as compared to HC. The percentages of IL-21+ CD4+ T-cells and CD8+ T-cells correlated significantly with the percentages of IL-17A+ CD4+ T-cells and CD8+ T-cells, respectively. The relative expression of BCL-6 and ROR-γt did not differ between SLE patients and HC. IL-21R expression occurred mainly on B-cells and was not different comparing SLE patients and HC.

CONCLUSIONS

This study demonstrates an increased proportion of IL-21+ T-cells in SLE patients correlating with the proportion of IL-17+ T-cells. This suggests a pivotal role of IL-21 in the pathogenesis of SLE.

Increased expression of Toll-like receptors by monocytes and natural killer cells in ANCA-associated vasculitis

Introduction

Toll-like receptors (TLRs) are a family of receptors that sense pathogen associated patterns such as bacterial cell wall proteins. Bacterial infections are associated with anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). Here, we assessed the expression of TLRs 2, 4, and 9 by peripheral blood leukocytes from patients with AAV, and investigated TLR mediated responses ex vivo.

Methods

Expression of TLRs was determined in 38 AAV patients (32 remission, 6 active disease), and 20 healthy controls (HC). Membrane expression of TLRs 2, 4, and 9, and intracellular expression of TLR9 by B lymphocytes, T lymphocytes, NK cells, monocytes and granulocytes was assessed using 9-color flowcytometry. Whole blood from 13 patients and 7 HC was stimulated ex vivo with TLR 2, 4 and 9 ligands and production of cytokines was analyzed.

Results

In patients, we observed increased proportions of TLR expressing NK cells. Furthermore, patient monocytes expressed higher levels of TLR2 compared to HC, and in a subset of patients an increased proportion of TLR4⁺ monocytes was observed. Monocytes from nasal carriers of Staphylococcus aureus expressed increased levels of intracellular TLR9. Membrane expression of TLRs by B lymphocytes, T lymphocytes, and granulocytes was comparable between AAV patients and HC. Patients with active disease did not show differential TLR expression compared to patients in remission. Ex vivo responses to TLR ligands did not differ significantly between patients and HC.

Conclusions

In AAV, monocytes and NK cells display increased TLR expression. Increased TLR expression by these leukocytes, probably resulting from increased activation, could play a role in disease (re)activation.

T-helper cells as new players in ANCA-associated vasculitides

In anti-neutrophil cytoplasmic autoantibody-associated vasculitides (AAV), several observations support a key role of T-helper cells (CD4(+) T cells) in disease pathophysiology. An expanded population of effector memory CD4(+) T cells in AAV patients may contribute to tissue injury and disease progression. In addition, functional impairment of regulatory T cells (T(Regs)) is reported in AAV patients. A fraction of T(Regs) have the capacity to differentiate into Th17 cells in the context of a proinflammatory environment. Therefore, nonfunctionality of T(Regs) described in AAV patients may be caused by their conversion into IL-17-producing cells that may contribute to granulomatous vasculitis. Further investigations directed at the plasticity of T(Regs) in AAV patients are warranted.

Treatment of mucosa-associated lymphoid tissue lymphoma in Sjogren's syndrome: a retrospective clinical study

OBJECTIVE

To retrospectively analyze the clinical course of patients with mucosa-associated lymphoid tissue (MALT)-type lymphoma of the parotid gland and associated Sjögren's syndrome (SS).

METHODS

All consecutive patients with SS and MALT lymphoma (MALT-SS) diagnosed in the University Medical Center Groningen between January 1997 and January 2009 were analyzed. Clinical course and treatment outcome of SS and MALT lymphoma were evaluated.

RESULTS

From a total of 329 patients with SS, 35 MALT-SS patients were identified, with a median followup of 76 months (range 16-153 mo). MALT lymphoma was localized in the parotid gland in all cases. Treatment consisted of "watchful waiting" (n = 10), surgery (n = 3), radiotherapy (n = 1), surgery combined with radiotherapy (n = 2), rituximab only (n = 13), or rituximab combined with chemotherapy (n = 6). Complete response was observed in 14 patients, partial response in 1 patient, and stable disease in 20 patients. In 6 of 7 patients with initially high SS disease activity (M-protein, cryoglobulins, IgM rheumatoid factor > 100 KIU/l, severe extraglandular manifestations), MALT lymphoma progressed and/or SS disease activity increased after a median followup of 39 months (range 4-98 mo), necessitating retreatment. Only 1 patient with MALT who had low SS disease activity showed progression of lymphoma when left untreated.

CONCLUSION

An initially high SS disease activity likely constitutes an adverse prognostic factor for progression of lymphoma and/or SS. Such patients may require treatment for both MALT lymphoma and SS. In SS patients with localized asymptomatic MALT lymphoma and low SS disease activity, a "watchful waiting" strategy seems justified.