Clinicopathologic Characteristics and Outcomes of Lupus Nephritis With Antineutrophil Cytoplasmic Antibody: A Retrospective Study

Serum antineutrophil cytoplasmic antibody positivity at the time of renal biopsy is associated with disease activity of lupus nephritis

OBJECTIVE

To investigate the correlations between serum antineutrophil cytoplasmic antibody (ANCA) and clinicopathological features, induction treatment response, and prognosis of lupus nephritis (LN) patients.

METHODS

In this retrospective study, biopsy-proven LN patients from October 2010 to September 2020 were tested for serum ANCA by indirect immunofluorescence and ELISA and were divided into ANCA-positive group and ANCA-negative group. The clinicopathological data of the two groups were analyzed and compared.

RESULTS

Thirty-five of 115 patients (30.43%) were seropositive for ANCA. ANCA-positive patients had significantly higher systemic lupus erythematosus activity index and activity index scores, higher 24-h urinary protein, and lower complement three levels (p = 0.001, 0.028, 0.023, 0.009, respectively). The incidences of oral ulcers, thrombocytopenia, and leukocyturia, and the positive rates of anti-dsDNA antibody and anti-histone antibody were significantly higher in ANCA-positive group (p = 0.006, 0.019, 0.012, 0.001, 0.019, respectively). Class IV LN and fibrinoid necrosis/karyorrhexis were significantly more common in the ANCA-positive group (p = 0.027, 0.002). There was no significant difference in the total remission rate of ANCA-positive patients receiving cyclophosphamide and mycophenolate mofetil as induction therapies (83.33% vs. 66.67%, p > 0.05), while patients receiving cyclophosphamide as induction therapy had a higher total remission rate than those receiving other immunosuppressants (83.33% vs. 20%, p = 0.028).

CONCLUSIONS

LN patients with ANCA seropositivity at renal biopsy have a significantly higher disease activity, and their pathological manifestations are predominantly proliferative LN. These patients require a more active immunosuppressive therapy with cyclophosphamide or mycophenolate mofetil to improve their remission rate.

ANCA in patients with systemic lupus erythematosus. A cross sectional study in Brazilian patients and review of literature

BACKGROUND

Antineutrophil cytoplasmatic antibodies (ANCA) have been detected in patients with systemic lupus erythematosus (SLE). In this study, we investigated the presence of ANCA in a sample of Brazilian SLE patients and its possible associations with clinical and serological outcomes. Additionally, we reviewed the literature of on ANCA in SLE.

RESULTS

The presence of ANCA was detected in 130 patients using indirect immunofluorescence (IIF). The test was positive in 29.9% of the cases (17.6% pANCA and 11.5% cANCA). Male sex and peripheral vasculitis were more prevalent in the ANCA-positive sample. cANCA was associated with lupus anticoagulant and pANCA had a positive association with peripheral vasculitis and a negative association with anti- SSB/La antibodies. In the 22 studies included in the literature review, a wide range of ANCA positivity was found (13% to 81.1% by IIF and 0 to 22.2% by ELISA). ANCA was associated with renal damage in the Asian population. Although other associations have been found in isolated studies, they were not consistently reported.

CONCLUSIONS

The ANCA prevalence found in this Brazilian sample was within the range reported in the literature and these autoantibodies were more frequent in males and in patients with vasculitis. The literature showed controversial results on the association between ANCA and SLE disease activity or clinical characteristics.

Lupus Nephritis Biomarkers: A Critical Review

Lupus nephritis (LN), a major complication in individuals diagnosed with systemic lupus erythematosus, substantially increases morbidity and mortality. Despite marked improvements in the survival of patients with severe LN over the past 50 years, complete clinical remission after immunosuppressive therapy is achieved in only half of the patients. Therefore, timely detection of LN is vital for initiating prompt therapeutic interventions and improving patient outcomes. Biomarkers have emerged as valuable tools for LN detection and monitoring; however, the complex role of these biomarkers in LN pathogenesis remains unclear. Renal biopsy remains the gold standard for the identification of the histological phenotypes of LN and guides disease management. However, the molecular pathophysiology of specific renal lesions remains poorly understood. In this review, we provide a critical, up-to-date overview of the latest developments in the field of LN biomarkers.

Clinical features and outcomes of patients with antineutrophil cytoplasmic antibody-positive systemic lupus erythematosus

Purpose: To investigate the clinical characteristics, pathological features, and outcomes of patients with antineutrophil cytoplasmic antibody (ANCA)-positive systemic lupus erythematosus (SLE) in northwest China.Methods: This retrospective study included 491 patients with SLE tested for ANCA antibodies and 171 patients with ANCA-associated vasculitis (AAV) as controls. Subgroup analysis limited to those with renal involvement, and by ANCA antibody subtype (PR3 vs MPO). To compare the proteinuria remission rates between ANCA-positive and ANCA-negative lupus nephritis (LN) groups, a logistic regression model was used for propensity score matching based on age, hemoglobin, and baseline estimated glomerular filtration rate (eGFR).Results: Compared to ANCA-negative SLE (n = 442), ANCA-positive SLE (n = 46) occur in older patients; however, these patients were younger than those with AAV (n = 167). The eGFR of patients with ANCA-positive LN (n = 25) was higher than that of patients having AAV with renal involvement (n = 56) but lower than that of patients with ANCA-negative LN (n = 163). Patients with SLE who had MPO-ANCA (n = 16) had higher levels of serum creatinine compared to those with PR3-ANCA (n = 30) (156.5 µmol/L vs. 45.5 µmol/L, p = 0.005). During the follow-up period, the remission rate of proteinuria in patients with ANCA-positive LN was lower than that of patients with ANCA-negative LN (50% vs. 75%, p = 0.008).Conclusion: Patients with ANCA-positive LN may have worse baseline renal function and lower protein remission rates compared to patients with ANCA-negative LN. ANCA titers should be regularly monitored throughout the follow-up period in patients with SLE, especially in cases of renal involvement.

Three Diseases Mediated by Different Immunopathologic Mechanisms-ANCA-Associated Vasculitis, Anti-Glomerular Basement Membrane Disease, and Immune Complex-Mediated Glomerulonephritis-A Common Clinical and Histopathologic Picture: Rapidly Progressive Crescentic Glomerulonephritis

Immune mechanisms play an important role in the pathogenesis of glomerulonephritis (GN), with autoimmunity being the main underlying pathogenetic process of both primary and secondary GN. We present three autoimmune diseases mediated by different autoimmune mechanisms: glomerulonephritis in vasculitis mediated by anti-neutrophil cytoplasmic antibodies (ANCAs), glomerulonephritis mediated by anti-glomerular basement membrane antibodies (anti-GBM antibodies), and immune complex-mediated glomerulonephritis. Some of these diseases represent a common clinical and histopathologic scenario, namely rapidly progressive crescentic glomerulonephritis. This is a severe illness requiring complex therapy, with the main role being played by therapy aimed at targeting immune mechanisms. In the absence of immune therapy, the crescents, the characteristic histopathologic lesions of this common presentation, progress toward fibrosis, which is accompanied by end-stage renal disease (ESRD). The fact that three diseases mediated by different immunopathologic mechanisms have a common clinical and histopathologic picture reveals the complexity of the relationship between immunopathologic mechanisms and their clinical expression. Whereas most glomerular diseases progress by a slow process of sclerosis and fibrosis, the glomerular diseases accompanied by glomerular crescent formation can progress, if untreated, in a couple of months into whole-nephron glomerulosclerosis and fibrosis. The outcome of different immune processes in a common clinical and histopathologic phenotype reveals the complexity of the relationship of the kidney with the immune system. The aim of this review is to present different immune processes that lead to a common clinical and histopathologic phenotype, such as rapidly progressive crescentic glomerulonephritis.

Serum ANCA as Disease Biomarkers: Clinical Implications Beyond Vasculitis

Usually associated with autoimmune diseases, anti-neutrophil cytoplasmic antibodies are also detected in other conditions, such as infections, malignancies, and after intake of certain drugs. Even if the mechanisms of production and their pathogenic role have not been fully elucidated yet, ANCA are widely recognized as a clinically alarming finding due to their association with various disorders. While ANCA target several autoantigens, proteinase-3, and myeloperoxidase are the ones proved to be most frequently related to chronic inflammation and tissue damage in murine models. Albeit these autoantibodies could be present as an isolated observation without any implications, ANCA are frequently used in clinical practice to guide the diagnosis in a suspect of small vessel vasculitis. Conditions that should prompt the clinician to test ANCA status range from various forms of lung disease to renal or peripheral nervous system impairment. ANCA positivity in the presence of an autoimmune disease, especially rheumatoid arthritis, or connective tissue diseases, is frequently correlated with more clinical complications and treatment inefficacy, even in the absence of signs of vasculitis. For this reason, it has been postulated that ANCA could represent the final expression of an immune dysregulation rather than a pathogenic event responsible for organs damage. Recently, it has also been proposed that ANCA specificity (PR3 or MPO) could possibly define ANCA-associated vasculitides better than clinical phenotype. This review aims at summarizing the latest advancements in the field of ANCA study and clinical interpretation.

Lupus-like nephritis with positive anti-neutrophil cytoplasmic antibodies and negative antinuclear antibodies

Antineutrophil cytoplasmic antibodies (ANCAs) are associated with small vessel vasculitis but their prevalence is not rare in other immune diseases. In lupus nephritis (LN), their pathological role and clinical relevance have been the target of controversial views.

We present a case of acute kidney injury and nephrotic syndrome in a young woman with diffuse global proliferative and membranous nephritis on her kidney biopsy, showing a full-house immunofluorescence pattern, very allusive of class IV + V LN, but lacking associated clinical criteria and laboratory findings to support the diagnosis of systemic lupus erythematosus (SLE). Furthermore, the patient presented with high titers of ANCA, steadily decreasing alongside the renal function and proteinuria improvements, with mycophenolate mofetil (MMF) and steroid treatment.

The authors believe this is a case of lupus-like nephritis, in which ANCAs are immunological markers, although they are not directly involved in the pathogenesis.

Level and avidity of antineutrophil cytoplasmic antibodies specific to lactoferrin are useful biomarkers in systemic lupus erythematosus

OBJECTIVES

To evaluate specificity, level, and avidity of antineutrophil cytoplasmic antibodies (ANCA) in systemic lupus erythematosus (SLE). There are no studies of ANCA avidity in SLE.

METHODS

Level (ELISA) and avidity (ELISA) of myeloperoxidase (MPO-), proteinase 3 (PR3-), lactoferrin (LF-), cathepsin G, elastase (EL-), and bactericidal/permeability increasing protein (BPI)-ANCA in 142 SLE patients were studied. SLE activity was measured by SLEDAI-2 K. 25/40 ANCA-positive patients were immunoserologically followed (12 ± 2 months).

RESULTS

40/142 (28.2%) SLE patients were ANCA-positive: LF- (21/40), MPO- (19/40), EL- (6/40), PR3- (3/40), and BPI-ANCA (1/40). Only LF-ANCA were associated with renal manifestations (p < 0.05), and positive predictive value for renal involvement in ANCA-positive SLE was 76.2%. LF-ANCA-positive patients had higher SLEDAI-2 K (p < 0.05) and more frequently had anti-dsDNA (p < 0.05), low C3 (p < 0.001), and low C4 (p < 0.05) than LF-ANCA-negative patients. LF-ANCA level was in a positive correlation with SLEDAI-2 K, anti-dsDNA, and anti-C1q (p < 0.01) and in a negative correlation with C3 and C4 (p < 0.05). LF-ANCA avidity was higher than MPO-, EL-, PR3-, and BPI-ANCA avidity (p < 0.01). In LF-ANCA-positive patients, renal manifestations were associated with higher LF-ANCA level (p < 0.01) and avidity (p < 0.05). Based on LF-ANCA level and avidity, the receiver operating characteristic curves for discriminating patients with and without renal involvement had areas under the curves of 0.988 (95% CI: 0.949-1.00) and 0.813 (95% CI: 0.607-1.00), respectively. After the follow-up period, number of LF-ANCA-positive patients decreased (p < 0.01).

CONCLUSIONS

In contrast to other ANCAs, only LF-ANCA level correlated with activity and standard serological SLE markers. LF-ANCA level and avidity might be biomarkers of renal involvement in SLE. LF-ANCA are promising serological marker in SLE. Key Points • LF- and MPO-ANCA were most frequently found, while EL-, PR3-, and BPI-ANCA were rarely detected in SLE. • In contrast to other ANCAs, only LF-ANCA were associated with renal involvement, and their level correlated with the activity and standard serological markers of SLE. • LF-ANCA avidity was higher than other ANCAs' avidity; LF-ANCA level and avidity might be useful biomarkers of renal manifestations in SLE. • Detection of ANCA specificity, level, and avidity may help in the diagnosis of particular clinical SLE phenotypes.

Association between biopsies for anti-neutrophil cytoplasmic antibody-associated vasculitis and prognosis: a retrospective cohort study

OBJECTIVES

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic vasculitis with unknown aetiology. Although biopsies are helpful for diagnosing AAV, whether they improve the outcomes of AAV patients remains unknown. The objective of this study was to elucidate the association between biopsies and prognosis.

METHOD

This retrospective cohort study analysed health care records that were routinely collected at 190 hospitals in Japan from April 2005 to March 2019. Patients who were 18 years or older and hospitalized for AAV were eligible for inclusion. The primary outcome was the composite outcome of death and renal replacement therapy (RRT) during the first admission. We compared the outcome between the biopsy group and the no-biopsy group. The chi-square test was performed as a univariable analysis, and logistic regression analysis was performed as a multivariable analysis.

RESULTS

Three hundred and eighty-six patients were assessed in this study. One hundred fifty-four (39.9%) patients underwent biopsy, and 232 (60.1%) patients did not undergo biopsy during the first admission with AAV. In univariable analysis, the composite outcome of death and RRT were observed in 7 (4.5%) patients in the biopsy group and 25 (10.8%) patients in the no-biopsy group (OR 0.39 [95% CI 0.17, 0.94], P = 0.01). The result was consistent in the multivariable analysis (OR 0.31 [95% CI 0.12, 0.79], P = 0.01) after adjusting for potential confounders.

CONCLUSIONS

We showed that patients who underwent biopsy had a better prognosis in the composite outcome of mortality and RRT during admission using a Japanese healthcare record database. Key Points • This is the first study to elucidate the association between undergoing biopsy and prognosis. • Patients undergoing biopsy had a better prognosis in the composite outcome of mortality and RRT. • The proportion of patients who received transfusions was not significantly different between the two groups.

Antineutrophil Cytoplasmic Antibody in Lupus Nephritis: Correlation with Clinicopathological Characteristics and Disease Activity

BACKGROUND

Lupus nephritis (LN) represents 40%-50% of all systemic lupus erythematosus (SLE) patients, and rapidly progressive glomerulonephritis is associated with significant morbidity and mortality. Antineutrophil cytoplasmic antibody (ANCA) might be involved in the pathogenesis of LN.

OBJECTIVE

We evaluated the role of myeloperoxidase (MPO)-ANCA, proteinase 3 (PR3)-ANCA, and anti-glomerular basement membrane autoantibodies (anti-GBM autoAb) for the diagnosis of LN.

METHODS

In this cross-sectional study, 95 SLE patients were divided into 2 subgroups: LN group (n = 60) and non-LN group (n = 35). For further analysis, we subclassified the LN group into ANCA- positive (n = 16) and ANCA-negative (n = 44) LN patients. The entire Non-LN group was ANCA- negative. The SLE disease activity index (SLEDAI) was reported for each patient. Determination of MPO-ANCA, PR3-ANCA, and anti-GBM autoAb was performed using a novel multiplex bead-based technology in all patients. Data analyses were done using SPSS, version 20. Approval was obtained from the institutional review board of Zagazig University (ZU-IRB#6000).

RESULTS

Of 95 patients with SLE, 16 patients (16.84%) had ANCA-positive LN, all of which were MPO-ANCA. There was a positive correlation between MPO-ANCA and SLEDAI, as well as with class IV LN. Receiver operating characteristic analyses revealed that the sensitivity and specificity of MPO-ANCA were 81.3% and 99.8%, respectively, in discriminating LN from systemic lupus without nephritis.

CONCLUSION

MPO-ANCA level was significantly correlated with SLEDAI, inflammatory markers, kidney function tests, and LN class IV.

The Impact of Serum Anti-neutrophil Cytoplasmic Antibody on Clinical Characteristics and Outcomes in Pediatric-Onset Systemic Lupus Erythematosus Patients

Background: Systemic lupus erythematosus (SLE), an autoimmune disease, is characterized by the overproduction of autoantibodies. Anti-neutrophil cytoplasmic antibodies (ANCAs) have been recognized in SLE for decades. To date, their association with SLE disease activity, especially in pediatric-onset SLE (pSLE) patients, is limited.

Methods: We conducted a retrospective case-control study of pSLE patients with ANCAs from 2010 to 2020. Clinical characteristics, laboratory data, renal histological features, treatment and outcomes were analyzed.

Results: A total of 70 pediatric-onset SLE patients (9 ANCA-positive vs. 61 ANCA-negative) with a median age of 12.23 years (age ranging from 4 years to 18 years) at diagnosis were enrolled. Among patients with ANCAs, MPO-ANCA was found in seven and PR3-ANCA in two of those cases. Patients with ANCAs had a tendency to have hematuria compared with those without ANCAs (66 vs. 24.6%, respectively; p = 0.026). Of the 70 SLE patients, 8 with ANCAs and 44 without ANCAs underwent renal biopsies. Patients with ANCAs (25%, 2/8) were more likely to lack the typical full-house pattern in their renal immunofluorescence (IF) staining.

Conclusion: pSLE patients with ANCAs tend to have hematuria and an absence of typical IF histology. However, patients with and without ANCAs showed no difference in their clinical presentations and treatment outcomes.

Clinicopathologic characteristics and outcomes of lupus nephritis with positive antineutrophil cytoplasmic antibody

Aims: The aim was to determine whether anti-neutrophil cytoplasmic antibody (ANCA)-positive serology in patients with lupus nephritis (LN) is associated with different clinicopathologic features and outcomes.Methods: In our retrospective analysis, 283 patients were enrolled between 2013 and 2018. Thirty-six patients were ANCA-positive, and this group was compared with the remaining 247 patients who were confirmed as ANCA-negative at the time of biopsy.Results: ANCA-positive LN patients exhibited higher anti-dsDNA antibody titers and serum creatinine levels and lower serum hemoglobin concentrations than ANCA-negative LN patients. On pathological evaluation, segmental endocapillary hypercellularity observed by light microscopy was significantly more common in the ANCA-positive group. This feature was not significantly different in the treatment group, but the response to treatment was significantly different, as was remission (76.1% vs 69.4%, p < 0.001), between the ANCA-negative and ANCA-positive groups. During follow-up, the times to renal replacement therapy (RRT) and death were significantly different between the two unmatched groups (chi-square test, p = 0.041). Multivariate Cox analysis revealed that neurological disorders, ANCA positivity, and the chronicity index (CI) remained independent risk factors for patient survival. Pulmonary infection was the main cause of death and was most often due to fungal infection.Conclusion: ANCA-positive LN patients typically exhibited higher anti-dsDNA antibody titers, lower serum hemoglobin concentrations and worse renal function than ANCA-negative LN patients. Fungal infection was the main cause of death. We observed that ANCA positivity was an independent risk factor for patient survival.

[Clinicopathological features of children with lupus nephritis with positive antineutrophil cytoplasmic antibody]

OBJECTIVE

To study the clinicopathological features of children with lupus nephritis (LN) with positive anti-neutrophil cytoplasmic antibody (ANCA).

METHODS

A retrospective analysis was performed for the children who were diagnosed with LN in the First Affiliated Hospital of Sun Yat-sen University from January 2003 to December 2019. According to the results of serum ANCA, they were divided into two groups: ANCA-positive group (n=59) and ANCAnegative group (n=454). The two groups were compared in terms of clinical manifestations, histopathological features, remission rate, and prognosis.

RESULTS

Compared with the ANCA-negative group, the ANCA-positive group had a significant reduction in leukocytes and a significant increase in erythrocyte sedimentation rate (P < 0.05). There were no significant differences between the two groups in serum creatinine, urine protein, and urine red blood cell count (P > 0.05). A total of 308 children underwent kidney biopsy. The results on light microscopy showed that compared with the ANCAnegative group, the ANCA-positive group had a significantly higher proportion of children with cellular fibrous crescents (P < 0.05) and a significantly lower proportion of children with immune complex deposition (P < 0.05). There were no significant differences between the two groups in the remission rate and survival rate (P > 0.05).

CONCLUSIONS

Children with ANCA-positive LN tend to have more severe renal pathological injury, which is not exactly parallel with clinical manifestations, suggesting that timely renal biopsy is of great importance.

The clinical features of overlap syndrome (ANCA-associated crescentic glomerulonephritis [AACGN] and immune complex-mediated glomerulonephritis) are similar to those of AACGN alone

The overlap syndromes of anti-neutrophil cytoplasmic antibodies (ANCA)-associated crescentic glomerulonephritis (AACGN) and variants of immune complex medicated glomerulopathy (ICMGN) have been reported. But very few have compared AACGN alone with the overlap syndromes (AACGN plus ICMGN). The aim of this retrospective study was to make that comparison, following serum creatinine (sCr) to determine whether the two groups (AACGN-only group versus overlap group) would behave differently over time. We identified 14 cases with dual diagnoses of AACGN and various ICMGN in the overlap group. Data were collected and compared with 15 randomly selected AACGN-only cases over the similar period of time. The overlap syndrome represented 0.35% of our overall biopsies (14/4049). All 14 patients were ANCA positive and had crescentic formation. The percentage of crescents in the biopsies ranged from 10 to 78%. ICMGN included the following: membranoproliferative glomerulonephritis, post-infectious glomerulonephritis, membranous glomerulopathies, idiopathic mesangial proliferative glomerulonephritis, lupus nephritis, and IgA nephropathy. With the exception one biopsy revealing lupus nephritis class III, most of the ICMGN were mild. When compared to the AACGN-only group, there were no significant differences in clinical and histologic indices including age, percent of crescents, and sCr (on biopsy days, and over the follow-up periods), although the numbers of follow-up cases were limited over time. Our findings suggest that AACGN was the dominant disease process in the majority of overlap syndromes between AACGN and ICMGN, similar to the clinical processes of AACGN-only disease, therefore, the AACGN in overlap syndrome cases should be the main target for clinical management.

Clinical and pathological characteristics of ANA/anti-dsDNA positive patients with antineutrophil cytoplasmic autoantibody-associated vasculitis

Antineutrophil cytoplasmic autoantibodies (ANCA) associated vasculitis (AAV) consists of a group of systemic autoimmune diseases. The roles of serum anti-nuclear antibodies (ANA) and anti-double-stranded DNA (anti-dsDNA) antibodies in AAV patients remain unknown. This study investigated the prevalence of serum ANAs and anti-dsDNA antibodies in AAV patients and characterized the clinical and pathological features of these patients. A total of 218 AAV patients were enrolled. Clinical and pathological data of patients were analyzed retrospectively. Of the 218 AAV patients, 109 (50.0%) were positive for ANA, 45 (20.6%) were positive for anti-dsDNA, and 43 (19.7%) were positive for both. The AAV patients with ANA had severer kidney damage and more chronic renal histopathological changes compared to those who were negative for ANA. Specifically, patients positive for ANA had more hypertension, higher levels of urea nitrogen and serum creatinine, lower estimated glomerular filtration rate (eGFR), more end-stage renal disease (ESRD), severer proteinuria, glomerular sclerosis, tubular interstitial fibrosis and tubular atrophy, and were more likely to receive renal biopsies compared to ANA negative patients. The study found ANA and anti-dsDNA in AVV patients were not rare, ANA-positive AAV patients had severer kidney damage and more chronic renal histopathological changes compared to ANA-negative AAV patients. Renal biopsy is strongly recommended for differential diagnosis in such cases.

Differences in clinico-pathological characteristics and outcomes between proteinase 3-ANCA positivity and myeloperoxidase-ANCA positivity in lupus nephritis

BACKGROUND

Owing to the low prevalence of anti-neutrophil cytoplasmic antibodies (ANCA) in lupus nephritis (LN), there is no study about the differences between proteinase 3 (PR3)-ANCA positivity and myeloperoxidase (MPO)-ANCA positivity in LN until now.

METHODS

Here we perform a retrospective study to determine whether there are differences in clinic-pathological characteristics and renal outcomes between PR3-ANCA-positive LN patients and MPO-ANCA-positive LN patients.

RESULTS

A total of 26 (27.4%) PR3-ANCA-positive LN patients and 69 (72.6%) MPO-ANCA-positive LN patients (p < 0.001) were eligible for this study. Compared with PR3-ANCA-positive LN patients, MPO-ANCA-positive LN patients had significantly higher levels of serum creatinine (109.6 µmol/l vs. 74.3 µmol/l, p = 0.02), lower titers of antinuclear antibodies (ANA) (128 vs. 256, p = 0.01), and higher serum concentrations of C3 and C4 (0.54 g/l vs. 0.36 g/l, p = 0.002; 0.12 g/l vs. 0.06 g/l, p < 0.001; respectively). Furthermore, the MPO-ANCA-positive group had higher scores for chronicity index (p = 0.007), including interstitial fibrosis (p = 0.001) and tubular atrophy (p = 0.03) on biopsy specimens. The renal survival rates for MPO-ANCA-positive LN patients were 94.1% at 1 year, 83.2% at 5 years and 79.6% at 10 years; these values were worse when compared with those of the PR3-ANCA-positive group, which were 100%, 100% and 100%, respectively.

CONCLUSION

MPO-ANCA-positive LN patients had more severely impaired baseline renal function and less active lupus serology. More severely chronic pathological changes, including interstitial fibrosis and tubular atrophy on renal specimens, occurred in MPO-ANCA-positive LN patients. We found that MPO-ANCA-positive LN patients had worse renal outcomes.

ANCA positivity at the time of renal biopsy is associated with chronicity index of lupus nephritis

We investigated the association of antineutrophil cytoplasmic antibody (ANCA) positivity with lupus nephritis (LN) activity, histological features and prognosis in Korean patients with biopsy-proven LN having the results of both myeloperoxidase (MPO-ANCA) and proteinase 3 (PR3)-ANCA. We retrospectively reviewed the medical records of 91 LN patients having the results of ANCA. We divided patients with LN into the two groups according to the ANCA positivity. We collected clinical and laboratory data at kidney biopsy and histological features such as LN class including class I, II, III, IV-S, IV-G and V, and activity and chronicity index. We evaluated prognosis of LN during the follow-up by death and kidney failure. Twelve of 91 patients (13.2%) had ANCA at kidney biopsy. There were no differences in demographic data, comorbidities, reasons for kidney biopsy and laboratory data at kidney biopsy between patients with and without ANCA. In 12 LN patients with ANCA, Class III was the most frequently observed LN class (41.7%), while in 79 LN patients without ANCA, class IV-G was the most often detected LN class (35.4%). There were no meaningful differences in classes of LN between the two groups. On the other hand, patients with ANCA exhibited the higher median chronicity index than those without (2.5 vs. 1.0, P = 0.028), unlike activity index. ANCA positivity exhibited no association with death or kidney failure during the follow-up. ANCA positivity at kidney biopsy is associated with chronicity index of LN.

ANCA-Associated Necrotizing Glomerulonephritis Overlapping with Mesangial Proliferative Lupus Nephritis Refractory to Plasmapheresis, Steroid Pulse Therapy, and a Combination of Mycophenolate Mofetil and Rituximab

Necrotizing glomerulonephritis (GN) associated with antineutrophil cytoplasmic antibody (ANCA) has been increasingly recognized in the context of class III or IV lupus nephritis (LN), hereafter designated as ANCA-associated necrotizing LN. While this subset of GN appears to portend an unfavorable renal outcome, it is not clear whether it represents a distinct entity and benefits from a more aggressive therapy. We report a 78-year-old woman who presented with rapidly progressive GN and was found to have a double-stranded DNA (dsDNA) antibody, hypocomplementemia, antiphospholipid antibody, and strongly positive myeloperoxidase antibody. Renal pathology showed necrotizing and crescentic GN on a background of mesangial proliferative GN. Her kidney disease did not improve despite the treatment with plasmapheresis, three doses of methylprednisolone pulse therapy followed by prednisone at 1 mg/kg/day, rituximab, and mycophenolate mofetil. This case not only reinforces the notion that ANCA-associated necrotizing LN is associated with high dsDNA antibody, hypocomplementemia, and worse renal outcome but also adds new insight into the full spectrum of this emerging disease entity by demonstrating that the concurrence of ANCA-associated vasculitis is not specific for class III or IV LN but can also be seen on a background of class II LN.

Treatment and clinicopathological characteristics of lupus nephritis with anti-neutrophil cytoplasmic antibody positivity: a case-control study

OBJECTIVE

To assess the clinical features, pathological presentations, treatments and outcomes of lupus nephritis (LN) with anti-neutrophil cytoplasmic antibody (ANCA) positivity.

DESIGN

A case-control study.

METHODS

Patients (n=49) were retrospectively included from Jinling Hospital in China if presenting with biopsy-proven ANCA-positive LN between 1985 and 2008. Clinicopathological characteristics and outcomes were analysed and compared with those of a control group (n=1279). We further compared treatment responses and outcomes of ANCA-positive LN patients based on the treatment issued.

RESULTS

The study included 40 women and 9 men (median age 33 years at biopsy): 38 with myeloperoxidase (MPO)-ANCA, 7 with proteinase 3 (PR3)-ANCA and 4 with double positivity. ANCA-positive LN patients exhibited higher haematuria, serum creatinine levels and systemic lupus erythematosus disease activity index scores. On pathological evaluation, class IV LN was predominant, accounting for 61.22% of cases. Light microscopy revealed significantly higher activity index and chronicity index scores, including cellular crescents, interstitial inflammation, tubular atrophy and interstitial fibrosis. ANCA-positive LN patients receiving mycophenolate mofetil as induction therapy had a higher remission rate and better renal outcomes than those receiving cyclophosphamide. During follow-up, end-stage renal disease developed in seven (14.29%) ANCA-positive LN patients, all of them were MPO-ANCA positive.

CONCLUSIONS

The characteristics of ANCA-positive LN were massive haematuria and advanced renal insufficiency. We observed a higher remission rate and better prognoses when using mycophenolate mofetil than when using cyclophosphamide as induction therapy.