ANCA-associated systemic vasculitis in Japan: clinical features and prognostic changes

Clinical outcomes and clinico-pathological correlations in children with MPO-ANCA-associated glomerulonephritis showing renal arteritis

The aim of this study was to evaluate the clinical features, pathological characteristics, and prognosis in myeloperoxidase (MPO)-antineutrophil cytoplasmic antibodies (ANCA)-associated glomerulonephritis (AAGN) with renal arteritis. The study involved 97 children from five pediatric clinical centers with MPO-AAGN who exhibited distinct clinical features. The patients were divided into AAGN-A+ and AAGN-A-, based on the presence or absence of arteritis, and the disparities in clinical, histopathological characteristics, and prognosis between the two groups was evaluated. In contrast to the AAGN-A- group, the children in the AAGN-A+ group exhibited more pronounced clinical symptoms and renal pathological injury. Arteritis positively moderately correlated with the serum creatinine, interleukin-6, urinary neutrophil gelatinase-associated lipocalin, negatively moderately correlated with serum complement C3. The renal survival rate in the AAGN-A+ group was significantly poorer than AAGN-A- group (χ2 = 4.278, p = 0.039). Arteritis showed a good predictive value for end-stage kidney disease (ESKD), and C3 deposition, ANCA renal risk score and arteritis were independent risk factors for the development of ESKD in children with MPO-AAGN. Arteritis is a significant pathological change observed in children with MPO-AAGN, and the formation of arteritis may be related to the inflammatory response and activation of the complement system.

Lymphopenia is a risk factor for severe infections in older patients with microscopic polyangiitis: a retrospective cohort study in Japan

Objective

Previous studies have identified the predictors of severe infections in ANCA-associated vasculitis. However, lymphopenia has not been fully evaluated as a predictor of subsequent severe infections in patients with microscopic polyangiitis (MPA). The aim of this study was to assess the association between lymphopenia and severe infections requiring hospitalization after receiving immunosuppressive therapy for MPA.

Methods

This single-centre retrospective cohort study included 130 consecutive patients with newly diagnosed MPA from Aichi Medical University Hospital, Japan, who received immunosuppressive therapy between March 2004 and December 2020. The relationship between lymphopenia and subsequent severe infections was assessed using time-dependent multivariate Cox proportional hazard models adjusted for clinically relevant factors.

Results

During the follow-up period (median: 38 months; interquartile range: 15-63 months), 56 severe infectious episodes occurred in 51 patients (39.2%). Time-dependent multivariate Cox proportional hazard analyses identified older age [adjusted hazard ratio (HR) = 1.74 per 10 years, 95% CI: 1.13, 2.67], methylprednisolone pulse therapy (adjusted HR = 2.04, 95% CI: 1.03, 4.02), moderate lymphopenia (vs normal, adjusted HR = 7.17, 95% CI: 3.10, 16.6) and severe lymphopenia (vs normal, adjusted HR = 36.1, 95% CI: 11.8, 110.9) as significant predictors of severe infection.

Conclusion

Lymphopenia is a predictor of subsequent severe infections in patients with MPA who receive immunosuppressive therapy. These results suggest the importance of sustained infection surveillance, particularly in older patients who develop lymphopenia during strong immunosuppressive therapy.

A Case of an Elderly Woman Who Developed Corneal Perforation in the Clinical Course of Myeloperoxidase Positive Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Antineutrophil cytoplasmic antibody- (ANCA-) associated vasculitis (AAV) is a systemic vasculitis characterized by ANCA positivity and categorized into three main types: microscopic polyangiitis, granulomatosis with polyangiitis, and eosinophilic granulomatous with polyangiitis. Although AAV leads to systemic organ injury, such as of the lungs, kidneys, nerves, and skin, patients with AAV sometimes develop ocular lesions. Here, we report the case of an elderly woman who had been treated for AAV for seven years. She developed scleritis and relapsed twice, with elevation of serum disease markers such as ANCA titer and C-reactive protein. After the decline of these markers due to treatment with additional medication, her scleritis relapsed again and caused a corneal ulcer, which resulted in perforation without obvious marker elevation. She did not present with any symptoms of organ injury, except for ocular lesions. She was treated with surgery, followed by methylprednisolone and rituximab therapy. Subsequently, her ocular lesions and symptoms improved, and she did not relapse. AAV can cause various ocular manifestations. Although C-reactive protein and ANCA titers are useful markers of disease activity and the relapse of AAV complications, including ocular lesions, these markers do not always increase at the time of worsening ocular lesions. Therefore, it is important for clinicians treating patients with AAV to pay careful attention to serum data and physical findings, including the eyes.

Granulomatosis with polyangiitis presenting as a solitary renal mass: a case report

BACKGROUND

Granulomatosis with polyangiitis (GPA) is characterized by necrotizing granulomatous vasculitis involving small-sized vessels in the upper airways, lower airways, and kidneys. Renal pathology is usually characterized by focal segmental necrotizing glomerulonephritis, which often leads to rapidly progressive renal failure. This type of renal involvement is usually unapparent on radiography. The presence of a renal mass in a patient with GPA, although extremely rare, is recognizable. Herein, we report a rare case of GPA presenting as a solitary renal mass and present a review of the literature.

CASE PRESENTATION

A 75-year-old woman presented with a solitary right kidney mass measuring 4 × 3.5 cm detected by enhanced computed tomography. There was no history of sinusitis, rhinitis, cough, or pneumonia suggestive of systemic GPA. Nephrectomy was performed based on the suspicion of renal cell carcinoma or malignant lymphoma. Three months later, she was admitted because her serum creatinine levels increased from 54.81 μmol/L to 405.76 μmol/L accompanied by a high C-reactive protein level of 159 mg/L. Anti-neutrophil cytoplasmic antibodies against myeloperoxidase and anti-proteinase 3 were negative. Histological examinations of the solitary renal mass revealed necrotizing granulomatous arteritis in the cortex and medullary vasa recta, surrounded by interstitial fibrosis, and focal segmental necrotizing glomerulonephritis in the localized lesion; however, signs of vasculitis were not observed in areas other than the solitary mass. Therefore, the patient was diagnosed with granulomatosis with polyangiitis (GPA). Despite treatment with prednisolone (30 mg/day), the patient developed oliguria with an elevation of her serum creatinine level to 583.44 μmol/L, which required hemodialysis within one month after the initiation of steroid therapy. The patient could successfully discontinue hemodialysis 21 months later, following a decrease in her serum creatinine level to 251.06 μmol/L.

CONCLUSIONS

GPA should be considered as one of the differential diagnoses of a solitary renal mass. Furthermore, patients with solitary renal masses associated with GPA may exhibit a favorable response to steroid or immunosuppressive treatment.

Development and internal validation of a model to predict long-term survival of ANCA associated vasculitis

Objectives

Risk stratification and prognosis prediction are critical for appropriate management of anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV). Herein, we aim to develop and internally validate a prediction model specifically for long-term survival of patients with AAV.

Methods

We thoroughly reviewed the medical charts of patients with AAV admitted to Peking Union Medical College Hospital from January 1999 to July 2019. The Least Absolute Shrinkage and Selection Operator method and the COX proportional hazard regression was used to develop the prediction model. The Harrell's concordance index (C-index), calibration curves and Brier scores were calculated to evaluate the model performance. The model was internally validated by bootstrap resampling methods.

Results

A total of 653 patients were included in the study, including 303 patients with microscopic polyangiitis, 245 patients with granulomatosis with polyangiitis and 105 patients with eosinophilic granulomatosis with polyangiitis, respectively. During a median follow-up of 33 months (interquartile range 15-60 months), 120 deaths occurred. Age at admission, chest and cardiovascular involvement, serum creatinine grade, hemoglobin levels at baseline and AAV sub-types were selected as predictive parameters in the final model. The optimism-corrected C-index and integrated Brier score of our prediction model were 0.728 and 0.109. The calibration plots showed fine agreement between observed and predicted probability of all-cause death. The decision curve analysis (DCA) showed that in a wide range of threshold probabilities, our prediction model had higher net benefits compared with the revised five factor score (rFFSand) and the birmingham vasculitis activity score (BVAS) system.

Conclusion

Our model performs well in predicting outcomes of AAV patients. Patients with moderate-to-high probability of death should be followed closely and personalized monitoring plan should be scheduled.

Predictive Factors of Cytomegalovirus Viremia during the Clinical Course of Anti-Neutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis: A Single Center Observational Study

We aim to elucidate factors to aid in the prediction of cytomegalovirus viremia during the treatment of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). We conducted a single-center, retrospective, observational study of 35 patients with newly diagnosed AAV. Factors associated with the development of CMV viremia were investigated via a logistic regression analysis. The CMV antigenemia test was performed in 25 patients (71%), of whom 15 (60%) were diagnosed with CMV viremia. Of these 15 patients, 5 developed a CMV infection. The total protein, hemoglobin, platelet count and lymphocyte counts at the time of the CMV antigenemia test were significantly lower in patients who developed CMV viremia. In addition, total protein, hemoglobin, platelet count and lymphocyte count also presented significantly decreasing trends in the following order: patients who did not develop CMV viremia, patients who developed CMV viremia without any symptoms, and patients who developed CMV infection. All patients with CMV recovered. In conclusion, the total protein, hemoglobin, platelet count and lymphocyte count may be useful markers for the prediction of CMV viremia and infection after the start of induction of immunosuppressive therapy for patients with AAV.

The efficacy and safety of mizoribine for maintenance therapy in patients with myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis: the usefulness of serum mizoribine monitoring

BACKGROUND

The life prognosis of elderly patients with myeloperoxidase-anti-neutrophil cytoplasmic antibodies-associated vasculitis (MPO-AAV) has been improved by reducing the corticosteroid or cyclophosphamide dose to avoid opportunistic infection. However, many elderly MPO-AAV patients experience recurrence and renal death. An effective and safer maintenance treatment method is necessary to improve the renal prognosis of MPO-AAV.

METHODS

Patients with MPO-AAV who reached complete or incomplete remission after induction therapy were prospectively and randomly divided into mizoribine (MZR; n = 25) and control (n = 28) groups. The primary endpoint was relapse of MPO-AAV. The patients' serum MZR concentration was measured before (C0) and 3 h after taking the MZR. The maximum drug concentration (Cmax) and the serum MZR concentration curves were determined using population pharmacokinetics parameters. We also assessed the relationship between the MZR concentrations and adverse events. The observation period was 12 months.

RESULTS

Fifty-eight MPO-AAV patients from 16 hospitals in Japan were enrolled. Ten patients relapsed (MZR group, n = 6; control group, n = 4; a nonsignificant between-group difference). Changes in the serum MZR concentration could be estimated for 22 of the 25 MZR-treated patients: 2 of the 11 patients who reached a Cmax of 3 μg/mL relapsed, whereas 4 of the 11 patients who did not reach this Cmax relapsed. The treatment of one patient with C0 > 1 μg/mL was discontinued due to adverse events. No serious adverse events occurred.

CONCLUSION

There was no significant difference in the recurrence rate of MPO-AAV between treatment with versus without MZR.

Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis Developing Pancreatic Lesion and Diabetes Mellitus: A Case Report and Review of the Literature

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) affects small blood vessels and causes severe systemic organ injury commonly affecting the lungs and kidney. However, gastrointestinal, especially pancreatic, lesions are rare. We report the case of a 67-year-old Japanese man diagnosed with myeloperoxidase (MPO) AAV who developed pancreatic lesions and diabetes mellitus. The patient was admitted to our hospital due to fever, cough, and weight loss. He developed progressive glomerulonephritis, lung nodules, and pancreatic swelling and mass. Additionally, laboratory examination revealed positive MPO-ANCA and elevated glycated hemoglobin A1c, which were suggestive of diabetes mellitus. Renal biopsy revealed necrotizing crescentic glomerulonephritis and vasculitis in the small arteries. Endoscopic ultrasound-guided fine needle aspiration of the pancreas was performed, and histological findings suggested the possibility of pancreatic vasculitis and parenchymal injury. The patient was diagnosed with AAV, which was managed with glucocorticoids. This improved the renal function and pancreatic lesions. Furthermore, blood glucose levels improved despite treatment with glucocorticoids. These findings suggest that AAV-related pancreatic lesions worsened glycemic control. However, glucocorticoid therapy improved vasculitis and pancreatic lesions, which resulted in improved glycemic control.

Serum Sulfatide Levels as a Biomarker of Active Glomerular Lesion in Patients with Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis: A Single Center Pilot Study

Sulfatides are glycosphingolipids that are associated with coagulation and platelet aggregation. Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) activates platelet function and often leads to thrombotic complications. These facts suggest an association between serum sulfatides and AAV. We aimed to clarify the significance of serum sulfatide levels in patients with AAV. We conducted a retrospective, single-center, observational pilot study that included 35 patients who developed AAV and 10 control patients who were candidates for living-donor kidney transplantation. We compared serum sulfatide levels between the control and AAV patients. We analyzed the differences in serum sulfatide levels among four classes (focal, crescentic, mixed, and sclerotic class) of glomerular lesions that were categorized by histopathologic classification of ANCA-associated glomerulonephritis. Serum sulfatide levels in patients with AAV were significantly lower than those in the controls. Serum sulfatide levels were significantly different between the four classes. Additionally, serum sulfatide levels in the crescentic class were significantly lower than those in the other classes. Serum sulfatide levels were significantly correlated with albumin, cholesterol, C-reactive protein, and pentraxin 3. In conclusion, serum sulfatide levels are significantly correlated with inflammation, reflecting crescentic glomerulonephritis, which is an active glomerular lesion in AAV patients.

Epidemiology and temporal changes in the prognosis of rapidly progressive glomerulonephritis in Japan: a nationwide 1989-2015 survey

BACKGROUND

Rapidly progressive glomerulonephritis (RPGN) can progress to end-stage kidney disease within a short period. This study is a continuation of the chronological nationwide survey conducted by the Japan-RPGN working group.

METHODS

We examined a total of 2793 RPGN cases registered during four periods (1989-1998, 1999-2001, 2002-2008, 2009-2011) plus 1386 cases in 2012-2015. As potential prognostic determinants, we investigated the onset period, the clinical severity (CS) grade [classified according to age, serum creatinine (sCr) and C-reactive protein levels, and presence/absence of lung lesions], and causative disease.

RESULTS

The cumulative overall RPGN patient survival at 24 months kept improving over the five periods (72.0%, 72.9%, 77.7%, 83.0%, 84.9%, p < 0.001 for trend). The cumulative renal survival also improved in the latest period (68.7%, 75.4%, 76.7%, 73.4%, 78.2%, p < 0.001 for trend). The CS grade was well stratified to predict both life and renal prognoses. Anti-glomerular basement membrane disease (aGBMD)-RPGN had a poorer renal prognosis than other diseases. In anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV-RPGN, accounting for > 70% of the overall RPGN), the prognostic results were similar to that for overall RPGN. There was a much better renal prognosis for the latest period under the condition of sCr < 3 mg/dL (the 24-month cumulative renal survival: 97.9%), but not for sCr ≥ 3 mg/dL (61.5%).

CONCLUSIONS

In overall RPGN as well as AAV-RPGN, both life and renal prognoses tended to improve, but the favorable renal result was substantially limited to mild cases. There was no improvement of the renal prognosis in aGBMD-RPGN.

Survival in ANCA-Associated Vasculitides in a Peruvian Center: 28 Years of Experience

AIM

The aim of this study was to identify demographic and clinical risk factors for mortality in patients with antineutrophil cytoplasmic antibodies-associated vasculitides (AAVs) in a Peruvian tertiary referral hospital.

METHODS

Medical records of patients with AAV according to classification criteria or diagnosed by an experienced rheumatologist, covering the period between January 1990 and December 2018, were reviewed. Granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and renal-limited vasculitis were included. Potential predictors of mortality were demographic factors, clinical manifestations, antineutrophil cytoplasmic antibodies status, diagnosis, disease categorization, the 2009 Five Factor Score (FFS), and treatment. Cox regression models were used to determine the risk factors for mortality. Univariable and multivariable analyses using a backward selection method were performed.

RESULTS

One hundred ninety-six patients were included; female-to-male ratio was 2:1. The median (interquartile range) age at diagnosis and follow-up were 60.0 (51.0-68.0) and 4.8 (1.3-11.6) years, respectively. One hundred forty-eight patients (75.5%) had microscopic polyangiitis, 37 (18.9%) granulomatosis with polyangiitis, 5 (2.6%) eosinophilic granulomatosis with polyangiitis, and 6 (3.0%) renal-limited vasculitis. Overall survival rates at 1, 5, and 10 years were 83.4%, 68.2%, and 51.7%, respectively. Ocular involvement was protective (hazards ratio [HR], 0.36; 95% confidence interval [CI], 0.17-0.74; p = 0.006), whereas renal (HR, 2.09; 95% CI, 1.33-3.28; p = 0.001) and lung involvement (HR, 2.07; 95% CI, 1.31-3.28; p = 0.002) and the 2009 FFSs were predictive of mortality (2009 FFS = 1: HR, 2.46; 95% CI, 1.50-4.04; p < 0.001; 2009 FFS = 2: HR, 3.07; 95% CI, 1.54-6.10; p = 0.001; 2009 FFS = 3: HR, 13.29; 95% CI, 3.69-47.88; p < 0.001).

CONCLUSIONS

Ocular involvement was protective, whereas 2009 FFS ≥ 1 and renal and lung involvement were predictive factors of mortality in Peruvian AAV patients.

Demographic and Clinical Features of ANCA-Associated Vasculitides in a Peruvian Tertiary Center

AIM

The aim of this study was to identify the demographic and clinical features of patients with ANCA-associated vasculitides (AAVs) in a Peruvian tertiary referral hospital.

METHODS

Medical records of patients with AAV according to classification criteria or diagnosed by an experienced rheumatologist, and covering the period between January 1990 and December 2019, were reviewed. Granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), and renal-limited vasculitis (RLV) were included. Demographic factors (age at diagnosis, sex), disease duration, clinical manifestations (per organ involvement), creatinine level at diagnosis (milligram per deciliter), ANCA status, diagnosis, 2009 Five Factor Score, disease categorization, and treatment were recorded.

RESULTS

Two hundred twelve patients were included. Their female-to-male ratio was 1.9:1 (139 [65.6%]/73 [34.4%]), and their mean (SD) age at diagnosis was 59.2 (12.5) years. One hundred fifty-eight patients (74.5%) had MPA, 42 (19.8%) GPA, 7 (3.3%) RLV, and 5 (2.4%) EGPA. Neurological, lung, and renal involvements were the most frequently affected systems. Myeloperoxidase preferentially occurred in MPA (82.5%), whereas proteinase 3 did occur in GPA (79.5%). Microscopic polyangiitis patients were older (61.1 [11.5] years). Female sex predominated in MPA and RLV (2.4:1 and 6:1, respectively), but the opposite was the case for EGPA (1:4). Ear-nose-throat and ocular involvement were more frequent in GPA (both p's < 0.001), and neurological and cardiovascular involvement were more frequent in EGPA (p < 0.001 and p = 0.002, respectively).

CONCLUSIONS

This is one of the largest series of AAV patients in Latin America. Overall, female sex predominated. Microscopic polyangiitis was the most frequent AAV, and myeloperoxidase-ANCA was the most frequent antibody in Peruvian AAV population.

Risk factors for cytomegalovirus reactivation in patients with kidney disease under immunosuppressive therapy

BACKGROUND

Cytomegalovirus (CMV) is a herpes virus that causes latent infections, and its reactivation due to immunosuppression can cause fatal complications. CMV reactivation is a complication frequently occurring in patients with kidney disease who require immunosuppressive therapy, and, therefore, this study retrospectively examined its risk factors.

METHODS

Patients who received immunosuppressive therapy and underwent the CMV antigenemia test (CMV antigenemia: C7-HRP) for the treatment of primary nephritis (minimal change disease, membranous nephropathy, membranoproliferative glomerulonephritis, focal glomerulosclerosis, and IgA nephropathy) and anti-neutrophil cytoplasmic autoantibody (ANCA)-associated nephritis diagnosed at Saiseikai Kurihashi Hospital from January 2014 to December 2019 were recruited as study participants. Risk factors of CMV reactivation were examined using univariable and multivariable analyses.

RESULTS

Among the 64 patients (36 men and 28 women; median age, 72 years) included, 34 had primary nephritis (20 minimal disease changes, 10 membranous nephropathy, 1 membranoproliferative glomerulonephritis, 1 focal glomerulosclerosis, and 2 IgA nephropathy) and 30 had ANCA-associated nephritis. Regarding glucocorticoid (GC), 43 patients received oral GC therapy, whereas 21 received GC pulse therapy. CMV reactivation participants showed significant differences in age, ANCA-associated nephritis, hemoglobin level, lymphocyte count, maximum GC dosage, and hemodialysis in univariable analysis. Multivariate analysis showed significantly lower lymphocyte counts in CMV-reactivated patients, but no significant difference in other factors.

CONCLUSION

In patients with kidney disease, who require immunosuppressive therapy, CMV reactivation risk is high in patients with low lymphocyte count, and monitoring CMV during the treatment course could lead to early diagnosis and treatment of CMV disease.

Incidence and clinical predictors of infections in patients treated with severe systemic ANCA-associated vasculitis

BACKGROUND

Immunosuppressive therapy has improved the outcome of ANCA-associated vasculitis (AAV), but infectious morbidity and mortality remained high. Recognizing its risk factors seems crucial for prevention, aiming to increase survival of these patients.

METHODS

We investigated the incidence and types of infections and assessed predictive factors in 132 patients with severe systemic AAV.

RESULTS

Patients with lower than median incidence of total infections/patient-year during induction had lower baseline serum creatinine, dialysis requirement and Charlson comorbidity index (CCI), compared to those with higher than median incidence (P = 0.037; P = 0.024; P = 0.001; respectively). In subgroups with below and above than median number of severe infections/patient-year during induction, differences were found in baseline creatinine (P = 0.002) and dialysis requirement (P = 0.001); comparing the same cohorts during maintenance immunosuppression, baseline dialysis requirement, diabetes, CCI, and dose of cyclophosphamide (CYC) administered as induction therapy differed significantly (P = 0.019; P = 0.015; P = 0.001; P = 0.015, respectively). Severe infections were predicted by baseline serum creatinine (OR 1.002 [CI 1.001-1.003]) and pulmonary manifestation (OR 2.153 [CI 1.017-4.560]) during induction immunosuppression. In multivariable Cox regression model all-cause mortality was independently predicted by severe infection (HR 1.998 [CI 1.214-3.287]). Among the 168 positive cultures Gram-negative bacteria were responsible for blood stream infections in 33%, and respiratory tract infections in 72%.

CONCLUSIONS

Advanced renal failure, pulmonary involvement and high degree of comorbidities increase the risk of infection in AAV. Those who suffer infection during induction immunosuppression have worse long-term survival. Our findings indicate the need for high vigilance for infections and close follow-up of comorbidities when treating AAV.

Association between body mass index and severe infection in older adults with microscopic polyangiitis: a retrospective cohort in Japan

BACKGROUND

Although previous studies have evaluated risk factors for the incidence of severe infection in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV), the relationship between body mass index (BMI) and severe infection in AAV has not been elucidated. We hypothesized that older adults with AAV and a low BMI would be at a higher risk of infection. We therefore investigated the association between underweight status at AAV diagnosis and subsequent occurrence of severe infection in older adults with AAV.

METHODS

This single-center retrospective cohort study included 93 consecutive older adults with microscopic polyangiitis (MPA) treated at the Aichi Medical University Hospital in Japan between 2004 and 2018. The relationships between BMI at diagnosis and subsequent first severe infection were assessed using multivariate Cox proportional hazards models. The cumulative probability of the development of the first severe infection was calculated using the Kaplan-Meier method and the log-rank test. The level of statistical significance was set at P <  0.05.

RESULTS

During the median follow-up period of 19 (6-53) months, 29 (31.2%) patients developed at least one severe infection. Older age (adjusted hazard ratio [HR] = 2.02, 95% confidence interval [CI]: 1.14-3.52, per 10 years; P =  0.016), low BMI (< 18.5 kg/m² compared with normal BMI [18.5-23.0 kg/m²], adjusted HR =  2.63, 95% CI: 1.11-6.19; P =  0.027), and use of methylprednisolone pulse therapy (adjusted HR = 2.48, 95% CI: 1.07-5.76; P =  0.034) were found to be significant predictors of severe infection.

CONCLUSIONS

Low BMI was associated with a higher risk of severe infection in older adults with MPA, suggesting that careful management may be required to prevent this complication in this vulnerable group. Further studies are needed to elucidate the optimal treatment strategy for these patients.

ANCA-associated nephritis without crescent formation has atypical clinicopathological features: a multicenter retrospective study

BACKGROUND

Although crescentic glomerulonephritis is a hallmark of ANCA-associated nephritis, the clinicopathological features of ANCA-associated nephritis without crescent formation remain to be elucidated.

METHODS

We enrolled 146 Japanese ANCA-associated vasculitis (AAV) patients subjected to renal biopsy in 16 hospitals from 2001 to 2018, and compared those with and without crescent formation (C + and C- groups). The primary endpoint was end-stage renal disease (ESRD) and/or death.

RESULTS

C- group comprised 25 (17.1%) subjects. They had better renal function at the time of renal biopsy [estimated glomerular filtration rate (eGFR); median 41.7 vs 27.5 ml/min/1.73 m², p < 0.01] with minor urinary abnormalities but had a higher serum C-reactive protein level (8.8 vs 5.4 mg/dl, p = 0.01) and frequency of extra-renal lesions of AAV (76.0% vs 48.8%, p = 0.02) than C + group. Pathologically, C- group had a higher frequency of arteritis (40.0% vs 16.5%, p < 0.01). Kaplan-Meier method with log-rank tests showed no significant difference in renal and life prognosis combined, regardless of crescent formation. Multivariate Cox regression analysis revealed baseline eGFR, sclerotic class, and extra-renal lesions to be risk factors of ESRD and death combined. Competing risk analysis showed baseline eGFR and sclerotic class to be associated with ESRD, whereas baseline eGFR and extra-renal lesions were associated with death.

CONCLUSION

ANCA-associated nephritis without crescent formation had different clinicopathological features from those with crescent formation, suggesting an atypical subtype of ANCA-associated nephritis. Despite the better renal function at the time of renal biopsy, these results suggest that this subtype requires especially careful attention, especially in the presence of extra-renal involvement.

A case report of progressive multifocal leukoencephalopathy during steroid treatment for ANCA-associated renal vasculitis

CASE REPORT

an 80-year-old woman presented with rapidly progressive glomerulonephritis and was admitted to our hospital. Myeloperoxidase-specific antineutrophil cytoplasmic antibody (MPO-ANCA) was positive. We diagnosed ANCA-associated renal vasculitis (ANCA-RV). Treatment was initiated with intravenous methylprednisolone pulse therapy, followed by prednisolone (PSL) at 30 mg/day. We gradually reduced the PSL dose to 7.5 mg/day over 6 months. At that time, the patient developed disturbances of consciousness which progressed subacutely. MRI revealed regions of patchy white matter with an increased signal on T2-weighted, fluid attenuated inversion recovery (FLAIR) sequences and diffusion-weighted sequences. JC virus DNA was detected in the cerebrospinal fluid (CSF) by polymerase chain reaction (PCR), leading to a diagnosis of progressive multifocal leukoencephalopathy (PML). PML is a rare infectious demyelinating disease of the central nervous system caused by JC virus infection, occurring in highly immunosuppressed individuals such as HIV-infected patients and patients using some biological agents, and having a very poor prognosis. In the present case, PML may have been associated with steroid use, although there are very few case reports of PML in patients taking only steroids. We report progressive multifocal leukoencephalopathy during steroid treatment of ANCA-RV. When patients show progressive disturbance of consciousness during treatment for ANCA-RV, we need to take PML into consideration for differential diagnosis.

Initial high-dose corticosteroids and renal impairment are risk factors for early severe infections in elderly patients with antineutrophil cytoplasmic autoantibody-associated vasculitis: A retrospective observational study

Recent large observational studies of antineutrophil cytoplasmic autoantibody-associated vasculitis (AAV) show that severe infection is a major cause of death and that the majority of infections occur during the early phase of initiating remission-induction therapy. Many risk factors for severe infection have been suggested, but these have been inconsistent. Nevertheless, infectious risk factors in elderly patients with AAV have not been adequately investigated in previous studies.In this retrospective observational study, we examined potential predictors of severe infection within 90 days (early severe infections) after remission-induction therapy in patients with AAV aged 65 years or older. We included 167 consecutive elderly patients with AAV admitted to our hospital. Data from medical history and remission-induction therapy were analyzed for predictive risk factors associated with early severe infections. The relationship between initial doses of corticosteroids and cumulative incidence of severe infections was also analyzed. A multivariate analysis of risk factors for early severe infections was performed using logistic regression analysis. The Kaplan-Meier method was used to estimate the overall survival, and the log-rank test was used to evaluate the differences between patients with and without early severe infections. Gray method was used to compare the cumulative incidence of severe infections in patients who did and did not receive initial high-dose corticosteroids.Logistic regression analysis showed that initial high-dose corticosteroid administration (prednisolone ≥0.8 mg/kg/d) (odds ratio [OR] 3.86, P = .030) and serum creatinine levels at diagnosis ≥1.5 mg/dL (OR 5.13, P = .003) were independent predictors of early severe infection although administration of cyclophosphamide or rituximab was not. The cumulative incidence of severe infections was also significantly higher in patients who received initial high-dose corticosteroids (P = .042), and patients with early severe infections exhibited a high mortality rate within 6 months (P < .001).Our findings suggest that initial high-dose corticosteroids and renal impairment at diagnosis are associated with a higher risk of early severe infections and early death in elderly patients with AAV.

Relationship Between Immunosuppressive Therapy and the Development of Infectious Complications Among Patients with Anti-neutrophil Cytoplasmic Antibody-associated Vasculitis: A Single-center, Retrospective Observational Study

Introduction

Infectious complications are the leading cause of death in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). However, the relationship between initial immunosuppressive therapy and the development of infectious complications and the details of infectious complications among patients with AAV are uncertain. We thus aimed to determine the association between initial immunosuppressive therapy and infectious complications.

Material and methods

Forty-seven patients with newly diagnosed AAV were enrolled in this retrospective observational study (patients with eosinophilic granulomatous polyangiitis were excluded). We statistically determined the association between types of initial immunosuppressive therapy (methylprednisolone pulse and/or cyclophosphamide therapy) and the development of infectious complications. In addition, we investigated the causes and timing of the onset of infectious complications.

Results

Twenty-one (21; 44.7%) patients required antibiotic, antimycotic, or antiviral therapy because of the development of infectious complications. Multiple logistic regression analyses adjusted for age and sex revealed that methylprednisolone pulse and cyclophosphamide therapy were significantly associated with the development of infectious complications (odds ratio (OR) 4.85, 95% confidence interval (CI) 1.09-21.5, p = 0.038; OR 5.32, 95% CI 1.28-22.2, p = 0.022, respectively). Bacterial pneumonia and sepsis occurred in 10 (47.6%) and 6 (28.6%) patients, respectively. Almost half of these infectious complications, including fungal infection, developed within six months from the start of initial treatment.

Conclusion

Among patients with AAV, methylprednisolone pulse and cyclophosphamide therapy may increase the risk of developing infectious complications, such as pneumonia and sepsis, including fungal infection, particularly within six months from the initiation of treatment.

Oral candidiasis is a significant predictor of subsequent severe infections during immunosuppressive therapy in anti-neutrophil cytoplasmic antibody-associated vasculitis

BACKGROUND

Several studies have identified predictors of severe infections in antineutrophil cytoplasmic antibody-associated vasculitis (AAV). However, the development of oral candidiasis (OC) as a predictor of subsequent severe infections has not been evaluated. The aim of this study was to assess the association between OC and subsequent severe infection requiring hospitalization during immunosuppressive therapy in AAV.

METHODS

This single-center retrospective cohort study included 71 consecutive patients with newly diagnosed AAV from Aichi Medical University Hospital, Japan, starting immunosuppressive therapy between March 2013 and December 2018. The relationships between OC and subsequent severe infections were assessed using multivariate Cox proportional hazards models, adjusted for clinically relevant factors.

RESULTS

During the follow-up period (median, 23 months; interquartile range, 11-51 months), 25 severe infectious episodes occurred in 19 patients (26.8%) and OC occurred in 17 patients (23.9%). A log-rank test showed that the OC group was significantly associated with severe infection (P <  0.001). Multivariate Cox proportional hazards models identified lower serum albumin (per 1 g/dl adjusted hazard ratio (HR)  = 0.38, 95% confidence interval (CI): 0.15-0.85; P  =  0.018), use of methylprednisolone pulse (adjusted HR  =  5.44, 95% CI: 1.54-20.0; P  =  0.010), and OC (adjusted HR  = 5.31, 95% CI: 1.86-15.8; P  =  0.002) as significant predictors of severe infection. Furthermore, a significant effect modification of the use of methylprednisolone pulse on OC was observed (P <  0.001).

CONCLUSIONS

OC is one of the predictors of subsequent severe infections. The results suggest the importance of prolonging infection surveillance, especially for patients who developed OC under strong immunosuppressive therapy.

Fibrosis-4 index at diagnosis is associated with all-cause mortality in patients with microscopic polyangiitis and granulomatosis with polyangiitis

Background

The fibrosis-4 index (FIB-4) has been reported to be associated with all-cause mortality in several chronic diseases. In this study, we investigated whether at diagnosis could be associated with all-cause mortality in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA).

Methods

We retrospectively reviewed the medical records of 132 MPA and GPA patients without chronic liver diseases. Conventional risk factors included old age (≥ 65 years), male gender, diabetes mellitus (DM) and hypertension (HTN) at diagnosis, and disease-related risk factor included GPA, antineutrophil cytoplasmic antibody, Birmingham vasculitis activity score (BVAS) and five factor score (FFS (2009)). The cut-off of FIB-4 for significant liver fibrosis (S2–4) was set at 1.45.

Results

The mean age was 57.2 years and 27 patients (20.5%) had significant liver fibrosis (FIB-4 ≥ 1.45). Fifteen patients (11.4%) died during follow-up. In the univariable Cox Hazards model, age ≥ 65 years (Hazard ratio (HR) 5.055), DM (HR 3.446), HTN (HR 4.611), FFS (2009) ≥ 2 (HR 4.849) and FIB-4 ≥ 1.45 (HR 9.958) at diagnosis were significantly associated with all-cause mortality. In the multivariable Cox Hazards model, only FIB-4 at diagnosis ≥1.45 (HR 6.253, 95% confidence interval 1.398, 27.963) was associated with all-cause mortality during the follow-up in patients with MPA and GPA.

Conclusions

FIB-4 at diagnosis ≥1.45 is an independent predictor of all-cause mortality during follow-up in patients with MPA and GPA, and furthermore its predictive potential is higher than those of conventional and AAV-related risk factors for all-cause mortality.

Electronic supplementary material

The online version of this article (10.1186/s12876-019-1007-z) contains supplementary material, which is available to authorized users.

Antineutrophil Cytoplasmic Antibody-Associated Vasculitis in Korea: A Narrative Review

Antineutrophil cytoplasmic antibody-associated vasculitis (AAV) is a group of systemic necrotising vasculitides, which often involve small vessels, and which lead to few or no immune deposits in affected organs. According to clinical manifestations and pathological features, AAV is classified into three variants: microscopic polyangiitis, granulomatosis with polyangiitis (GPA), and eosinophilic GPA. The American College of Rheumatology 1990 criteria contributed to the classification of AAV, although currently the algorithm suggested by the European Medicines Agency in 2007 and the Chapel Hill Consensus Conference Nomenclature of Vasculitides proposed in 2012 have encouraged physicians to classify AAV patients properly. So far, there have been noticeable advancements in studies on the pathophysiology of AAV and the classification criteria for AAV in Western countries. However, studies analysing clinical features of Korean patients with AAV have only been conducted and reported since 2000. One year-, 5 year-, and 10 year-cumulative patient survival rates are reported as 96.1, 94.8, and 92.8%. Furthermore, initial vasculitis activity, prognostic factor score, age and specific organ-involvement have been found to be associated with either all-cause mortality or poor disease course. The rate of serious infection is 28.6%, and 1 year-, 5 year- and 10 year-cumulative hospitalised infection free survival rates range from 85.1% to 72.7%. The overall standardised incidence ratio of cancer in AAV patients was deemed 1.43 compared to the general Korean population.

Clinical and Pathological Characteristics of Elderly Japanese Patients with IgA Vasculitis with Nephritis: A Case Series

Objective This case series aimed to identify the clinical and pathological characteristics of elderly patients (≥60 years) with biopsy-proven IgA vasculitis with nephritis (IgAVN). Methods The clinical and pathological presentation and treatment outcomes were compared between two groups. Patients Patients with IgAVN who were ≥19 years old at the time of their renal biopsy were divided into elderly (≥60 years) and adult (19-59 years) groups. Results Of the 23 patients in our study, 13 were elderly. In the elderly group, the median age at the diagnosis was 68 years (range, 60-85 years), with a median follow-up period of 15 months (range, 3-80 months). Twelve elderly patients had comorbidities, including hypertension, diabetes mellitus, chronic kidney disease, cardiovascular disease, and malignancies. A decrease in the estimated glomerular filtration rate, as well as massive proteinuria and rapidly progressive nephritic syndrome, were more frequent in the elderly group than in the adult group. Furthermore, renal pathological changes, including cellular or fibrocellular crescents, interstitial fibrosis, tubular atrophy, and arteriosclerosis, were more severe among elderly patients than adult patients. All elderly patients were treated with glucocorticoids and had no incidence of end-stage renal disease at the final follow-up; in addition, nine elderly patients had reduced proteinuria with a preserved renal function. Adverse events, including infection, diabetes mellitus, and vascular disorders, were identified in nine patients. Three elderly patients died from severe infections. Conclusion IgAVN in elderly patients is characterized by severe renal involvement. Elderly patients are at higher risk than adults for treatment-related adverse events.

C-Reactive Protein to Serum Albumin Ratio Is an Independent Predictor of All-Cause Mortality in Patients with ANCA-Associated Vasculitis

PURPOSE

We investigated whether C-reactive protein (CRP) to serum albumin ratio (CAR) could be an independent predictor of all-cause mortality in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 170 patients with AAV. We collected clinical and laboratory data. We also examined AAV-related and traditional risk factors of all-cause mortality. To assess the hazard ratios of variables, we performed univariable and multivariable Cox hazard model analyses.

RESULTS

The mean age was 55.0 years and 53 patients (31.2%) were male among 170 patients with AAV (88 microscopic polyangiitis, 43 granulomatosis with polyangiitis, and 39 eosinophilic granulomatosis with polyangiitis). ANCA was detected in 129 patients (75.9%). The initial mean CRP and serum albumin were 41.1 (mg/L) and 3.6 (g/dL), and the mean CAR at diagnosis was 14.8. The most common risk factor of mortality was hypertension (42.4%), followed by chronic kidney disease ≥stage 3 (25.9%). Fourteen patients (8.2%) died during the mean follow-up of 56.7 months. In both multivariable Cox hazard model analyses, CAR at diagnosis was identified as an independent predictor of all-cause of mortality comparable to diabetes mellitus (DM). Moreover, patients with CAR ≥10.35 and having DM exhibited a higher frequency of all-cause mortality than those without.

CONCLUSION

CAR at diagnosis can be an independent predictor of all-cause mortality, comparable to DM, the conventional risk factor of mortality.

A Case of Microscopic Polyangiitis with Subarachnoid Hemorrhage and Cardiovascular Complications

Microscopic polyangiitis (MPA) is a primary systemic vasculitis that predominantly affects small and medium vessels. MPA is rarely complicated with central nervous system or cardiovascular disease. We report a very rare case of MPA complicated with cerebral infarction, cardiovascular disease, and fatal subarachnoid hemorrhage in a 54-year-old man. During the first six days of hospitalization the patient was diagnosed with rapid progressive glomerulonephritis (RPGN), cerebral infarction, and unstable angina. According to patient's symptoms and laboratory findings, were consisted with a diagnosis of severe MPA. Steroid pulse therapy was immediately introduced. However, the patient developed massive subarachnoid hemorrhage on the 8th day of hospitalization. The condition progressively deteriorated, and the patient died on the 33rd hospital day.

The influence of the Great East Japan earthquake on microscopic polyangiitis: A retrospective observational study

BACKGROUND

Antineutrophil cytoplasmic antibody-associated vasculitis is triggered by environmental factors, including silica dust exposure. Repeated tsunami waves brought a large volume of silica-containing sludge inland after the Great East Japan earthquake in 2011. We aimed to determine if the serious disaster influenced the clinical features of the microscopic polyangiitis.

METHODS

This is an observational retrospective study conducted in a single institute. A total of 43 patients were included based on the CHCC2012 criteria for microscopic polyangiitis from 2007 to 2015. We used the Poisson regression model to determine the incidence of microscopic polyangiitis within the annual population of the medical district. The participants were selected during a 3-year period from before (N = 13) to after the disaster (N = 20). The differences of parameters and the overall survival between the groups were analyzed.

RESULTS

The incidence of microscopic polyangiitis increased after the disaster (λ = 17.4/million/year [95%CI: 7.66-39.6] before the disaster and λ = 33.1/million/year [17.7-61.7] after the disaster, P = 0.044). A high Birmingham Activity Score was associated with a high incidence of microscopic polyangiitis after the disaster. The overall survival of the patients with microscopic polyangiitis declined significantly after the disaster.

CONCLUSIONS

The Great East Japan earthquake influenced the development of the microscopic polyangiitis in our restricted area. The patients who developed after the disaster had severe symptoms and a high mortality rate.

Myeloperoxidase anti-neutrophil cytoplasmic antibody affinity is associated with the formation of neutrophil extracellular traps in the kidney and vasculitis activity in myeloperoxidase anti-neutrophil cytoplasmic antibody-associated microscopic polyangiitis

Anti‐neutrophil cytoplasmic antibody (ANCA) is associated with small‐vessel vasculitis particularly in the kidneys and can induce the formation of neutrophil extracellular traps (NETs) from primed neutrophils. Recently we have reported that the induction of NETs correlates with ANCA affinity for myeloperoxidase (MPO) and disease activity in patients with MPO‐ANCA‐associated microscopic polyangiitis. To investigate whether MPO‐ANCA affinity is associated with the formation of NETs in vivo, we examined the occurrence of NETs in the renal tissues of patients with MPO‐ANCA‐associated microscopic polyangiitis and ANCA affinity by double immunofluorescence staining for NET components of citrullinated histone, MPO and PAD4 and by ELISA competition with MPO, respectively. We divided 30 MPO‐ANCA‐associated microscopic polyangiitis patients into 2 groups based on their ANCA affinity levels (IC₅₀ for the high: 0.11 ± 0.04 µg/mL (Group1) and IC₅₀ for the low: 0.66 ± 0.24 µg/mL (Group2)). Group1 showed a higher Birmingham vasculitis activity score (15.6 ± 5.7) and 73% of the patients presented clinically with rapidly progressive glomerulonephritis and histologically with focal/crescentic glomerulonephritis (GN). Group 2 showed a lower Birmingham vasculitis activity score (9.2 ± 4.9) and 73% of the patients presented clinically with chronic renal failure and histologically with mixed/sclerotic GN. Group 1 showed a much higher occurrence of NETs than Group 2. Our findings indicate that ANCA affinity was associated with the in vivo formation of NETs, which might be involved in the pathophysiology of patients with MPO‐ANCA‐associated microscopic polyangiitis.

Simple, readily available clinical indices predict early and late mortality among patients with ANCA-associated vasculitis

Background

The early identification of patients with ANCA-associated vasculitis (AAV) who are at increased risk for inferior clinical outcome at the time of diagnosis might help to optimize the immunosuppressive therapy. In this study we wanted to determine the predictive value of simple clinical characteristics, which may be applicable for early risk-stratification of patients with AAV.

Methods

We retrospectively analyzed the outcome of 101 consecutive patients with AAV receiving a protocolized immunosuppressive therapy. Baseline Birmingham Vasculitis Activity Score (BVAS) and non-vasculitic comorbidities were computed, then predictors of early (<90 days) and late (>90 days) mortality, infectious death, relapse and end stage kidney disease (ESKD) were evaluated.

Results

The baseline comorbidity score independently predicted early mortality (HR 1.622, CI 1.006–2.614), and showed association with infectious mortality (HR 2.056, CI 1.247–3.392). Patients with BVAS at or above median (=21) had worse early mortality in univariable analysis (HR 3.57, CI 1.039–12.243) (p = 0.031), and had more frequent relapses (p = 0.01) compared to patients with BVAS below median.

Conclusions

Assessing baseline comorbidities, beside clinical indices characterizing the severity and extension of AAV, might help clinicians in risk-stratification of patients. Future prospective studies are needed to investigate whether therapies based on risk-stratification could improve both short term and long term survival.

Clinical characteristics of and risk factors for serious infection in Japanese patients within six months of remission induction therapy for antineutrophil cytoplasmic antibody-associated vasculitis registered in a nationwide, prospective, inception cohort study

OBJECTIVES

The purpose of this study was to identify the clinical characteristics and predictors of serious infections (SIs) in the RemIT-JAV, a nationwide, prospective, inception cohort study for Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV).

METHODS

We analyzed SIs within six months of remission induction therapy in 156 AAV patients. Hazard ratios with 95% confidence intervals (CIs) for SIs were calculated using the COX proportional hazard model.

RESULTS

Sixty-three SIs in 42 patients were identified. The incidence rate (IR) of SIs was 87.59/100 patient-years. The median length of time to the onset of first SIs was 54 days. Hazard ratios (95%CI) for SIs were 1.97 (0.99-3.95) for age >65 years, 0.47 (0.25-0.89) for female sex, 2.11 (1.05-4.27) for the severe form of AAV, and 2.88 (1.49-5.88) for initial PSL >0.8 mg/kg/day in the first model, and 2.64 (1.39-5.01) for smoking and 3.27 (1.66-6.45) for initial PSL >0.8 mg/kg/day in the second model.

CONCLUSIONS

Lowering the IR of SIs in Japanese AAV patients is mandatory to improve the vital prognosis of these patients. For remission induction therapy of AAV patients with these risk factors, risk management of immunosuppressive treatment should be carefully considered.

Antineutrophil Cytoplasmic Antibody-associated Glomerulonephritis Complicated by Pneumatosis Intestinalis

Pneumatosis intestinalis is a characteristic imaging phenomenon indicating the presence of gas in the bowel wall. The link between pneumatosis intestinalis and various kinds of autoimmune diseases has been reported anecdotally, while information regarding the cases with antineutrophil cytoplasmic antibodies (ANCA)–associated vasculitis complicated by concurrent pneumatosis intestinalis is lacking. In this report, we describe our serendipitous experience with one such case of pneumatosis intestinalis in a patient with ANCA-associated glomerulonephritis. We also discuss several therapeutic concerns that arose in the current case, which had an impact on the pathogenesis of the disease.

A retrospective study on the outcomes of MPO-ANCA-associated vasculitis in dialysis-dependent patients

OBJECTIVES

This study investigated the clinical course of myeloperoxidase-antineutrophil cytoplasm autoantibody (MPO-ANCA)-associated vasculitis after starting dialysis.

METHODS

A retrospective review was conducted of the clinical charts of dialysis-dependent patients with MPO-ANCA-associated vasculitis who attended one of 8 associated clinics over the past 21 years.

RESULTS

Eighty-nine patients were included in the study; 88 had microscopic polyangiitis (MPA) and 1 had granulomatosis with polyangiitis. Of the 88 patients with MPA, 18 had renal-limited vasculitis. Twenty-one relapses occurred among 13 patients (frequency, 0.05 relapses/person-year; 95% confidence interval, 0.03-0.08). Mean time from start of dialysis to relapse was 65 ± 59 months. Cox multivariate analysis showed that pulmonary involvement was a predictor of relapse (hazard ratio [HR], 21.4) and mortality (HR, 4.60), and that patient age (HR, 1.10) and cyclophosphamide use (HR, 0.20) were significant predictors of mortality. Postdialysis 1- and 5-year survival rates were 83.0% and 65.6%, respectively; infection was the most frequent cause of death.

CONCLUSION

Pulmonary involvement was a predictor of relapse and mortality. Although relapse can occur long after the start of dialysis, incidence was low among dialysis-dependent patients. Prolonged maintenance immunosuppressive therapy might be limited to patients with pulmonary involvement in dialysis-dependent ANCA-associated vasculitis.

Pulmonary involvements of anti-neutrophil cytoplasmic autoantibody-associated renal vasculitis in Japan

BACKGROUND

Pulmonary involvement is one of the hallmark lesions of anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) as well as rapidly progressive glomerulonephritis (RPGN). However, the pulmonary involvement of AAV patients seems to differ between Europe and Japan, as does the ANCA serotype.

METHODS

This retrospective and prospective multicenter cohort study collected the clinical data of the features and outcomes of 1772 RPGN patients treated from 1989 to 2007 in Japan. Based on this nationwide RPGN survey, we analyzed the cases of 1147 AAV patients.

RESULTS

We found that 52.3% of the AAV patients had pulmonary involvements: 15.4% of the AAV patients had alveolar hemorrhage (AH), 26.2% had interstitial lung disease (ILD), 2.8% had bronchial asthma, 2.4% had pulmonary granuloma and 12.8% had a chest X-ray abnormality without AH, ILD or pulmonary granuloma. Patient survival was significantly different among the following six groups: the 5-year survival rate was 41.5% in the patients with AH, 50.2% in those with ILD, 67.9% in those with bronchial asthma, 62.5% in those with pulmonary granuloma, 55.8% in those with chest X-ray abnormality and 73.3% in those without pulmonary involvement. AH was one of the predictors of 1- and 5-year mortality for patient survival in AAV, and ILD was added as one of the predictors of 5-year mortality.

CONCLUSION

In these AAV patients, not only AH but also ILD was frequently observed. AH was associated with the prognosis, but ILD was associated with the long-term prognosis of AAV.

The level of urinary α1 microglobulin excretion is a useful marker of peritubular capillaritis in antineutrophil cytoplasmic antibody associated vasculitis

BACKGROUND

Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis affects small vessels in the kidney (i.e., arterioles, glomerular or peritubular capillaries, or venules). Although crescentic glomerulonephritis is a common histological finding, the incidence of peritubular capillaritis (PTC) or arteriolitis is unclear. Moreover, the laboratory data that reflect the degree of renal histological damage and distinguish between PTC and arteriolitis have not yet been clarified.

METHODS

We investigated laboratory data and histological findings from 11 patients diagnosed with ANCA-associated vasculitis (2 men and 9 women, mean age 70.3 ± 3.3 years) whose renal biopsies were performed between 2009 and 2014.

RESULTS

All patients were positive for myeloperoxidase (MPO)-ANCA. PTC or arteriolitis was detected in six patients (54.5 %), respectively. The only significant positive relationship between laboratory data and histological findings observed was that between levels of urinary α1 microglobulin (u-α1MG) excretion and the percentage of tubular atrophy and interstitial fibrosis (r = 0.67, p = 0.035). No significant differences in laboratory data were found between patients with or without arteriolitis. However, the levels of u-α1MG excretion were significantly higher in patients with PTC than in those without PTC (75.2 ± 19.5 vs. 15.0 ± 3.6 mg/dl, p = 0.035).

CONCLUSION

PTC or arteriolitis occurs at a high rate independently of crescentic glomerulonephritis in ANCA-associated vasculitis patients. The levels of u-α1MG excretion reflect the degrees of tubular atrophy and interstitial fibrosis. Moreover, high levels of u-α1MG excretion suggest that PTC is more likely than arteriolitis in ANCA-associated vasculitis patients.

Characteristics of MPO-ANCA-positive granulomatosis with polyangiitis: a retrospective multi-center study in Japan

We studied the clinico-pathological differences among PR3-ANCA-positive granulomatosis with polyangiitis (PR3-GPA), MPO-ANCA-positive GPA (MPO-GPA) and microscopic polyangiitis (MPA). ANCA-associated vasculitis (AAV) was classified using the European Medicines Agency classification. We retrospectively analyzed 38 patients with GPA and 41 with MPA treated in eight hospitals in Japan. Of the patients with GPA, 17 were positive for MPO-ANCA, and 15 for PR3-ANCA. All patients with MPA were MPO-ANCA positive. The mean ages of those with MPO-GPA were 69.6 years old, 10 years older than those with PR3-GPA. The majority (82 %) of patients with MPO-GPA were woman, a significantly greater proportion than for PR3-GPA. We also found that ear, nose and throat (ENT), nervous system involvement were significantly more common in MPO-GPA, but renal function was less impaired than those with MPA. Both PR3-GPA and MPO-GPA relapsed more frequently than MPA, but overall survival was significantly better (P < 0.01 and P < 0.05, respectively). Univariate analysis identified the following factors as predictors of a poor prognosis: MPA (P < 0.01), pulmonary UIP pattern (P < 0.005) Cr ≥ 1.7 mg/dl (P < 0.01) and absence of ENT involvement (P < 0.05), which were characteristics of MPA. In our cohort, MPO-GPA was most likely to affect older women and was associated with otitis media, nervous system involvement, mild renal impairment and more favorable outcome. It is clinically useful to differentiate MPO-GPA from MPA and PR3-GPA in patients with AAV.

Monitoring with serum SP-A, SP-D, and KL-6 in a patient with interstitial pneumonia complicated with ANCA-associated glomerulonephritis

A 69-year-old woman was admitted to hospital, complaining of fatigue and dry cough. Her renal function deteriorated rapidly, and the laboratory findings showed elevated myeloperoxidase-specific anti-neutrophil cytoplasmic antibody (ANCA). Renal biopsy examination revealed crescentic glomerulonephritis (pauci-immune type), and linear opacities and a honeycomb appearance in both lower lobes was evident on the chest computed tomography scan. The patient was diagnosed as having ANCA-associated glomerulonephritis complicated with mild interstitial pneumonia (IP). Treatment with methylprednisolone pulse therapy improved both her renal function and IP, but her lung lesions worsened during the course of tapering the prednisolone doses. After careful observation, her IP improved gradually without specific treatment. Worsening or improvement of her lung lesions was accompanied by changes in the serological markers of IP, namely, surfactant protein-A, surfactant protein-D, and KL-6. We found that monitoring these markers was helpful in diagnosing and managing IP in our patient with ANCA-associated vasculitis.

Significance of small renal artery lesions in patients with antineutrophil cytoplasmic antibody-associated glomerulonephritis

OBJECTIVE

Antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis is a vasculitis affecting the glomerular capillaries and small renal arteries. Although crescent formation has been reported to be characteristic of this condition, the significance of coexisting vasculitis affecting the small renal arteries has not been investigated.

METHODS

Fifty patients with ANCA-positive rapidly progressive glomerulonephritis whose renal biopsy specimens contained arterioles and/or interlobular arteries were retrospectively evaluated. Cellular crescents and/or necrotizing glomerulonephritis were noted in all 50 patients. Ten patients had vasculitis of the small renal arteries (group A) and 40 patients were without such vasculitis (group B). The clinical features of these 2 groups were compared.

RESULTS

Group A comprised 4 patients who had granulomatosis with polyangiitis (GPA) and 6 with microscopic polyangiitis (MPA), while group B included 1 patient with GPA and 39 with MPA. No patient in either group had eosinophilic granulomatosis with polyangiitis. The C-reactive protein (CRP) level was significantly higher in group A compared with group B (11.58 ± 6.19 vs 2.7 ± 3.55 mg/dl, p < 0.05), and pulmonary involvement was more frequent in group A than group B (80% vs 37.5%, p < 0.05).

CONCLUSION

In patients with ANCA-positive glomerulonephritis, vasculitis of small renal arteries may be associated with systemic vasculitis (including pulmonary involvement) because of elevated CRP, a systemic inflammatory marker related to overproduction of interleukin 6.

Comparison of phenotype and outcome in microscopic polyangiitis between Europe and Japan

OBJECTIVE

There are differences between Europe and Japan in the incidence and antineutrophil cytoplasmic antibody (ANCA) serotype of patients with microscopic polyangiitis (MPA). However, differences in phenotype or outcome have not been explored. We aimed to identify differences in phenotype and outcome of MPA between Europe and Japan.

METHODS

Sequential cohorts of patients with MPA and renal limited vasculitis were collected from European and Japanese centers (n = 147 and n = 312, respectively). Trial databases from the European Vasculitis Society and the Japanese patients with Myeloperoxidase (MPO)-ANCA-Associated Vasculitis (JMAAV) trial were studied (n = 254 and n = 48, respectively). We evaluated baseline characteristics including ANCA status and organ involvement, treatment, survival, and renal survival. Differences in survival and renal survival were studied using multivariate analysis.

RESULTS

The non-trial cohorts showed patients with MPA in Japan had a higher age at onset, more frequent MPO-ANCA positivity, lower serum creatinine, and more frequent interstitial pneumonitis than those in Europe (all p < 0.01). Comparisons between the trial databases demonstrated similar results. Cumulative patient survival and renal survival rates were not different between Europe and Japan (p = 0.71 and p = 0.38, respectively). Multivariate analysis identified age at onset, serum creatinine, gastrointestinal, and respiratory involvement as factors with higher risk of death. For endstage renal failure, serum creatinine and use of plasma exchange were identified as factors with higher risk, and immunosuppressant use as lower risk factors.

CONCLUSION

Phenotypes in patients with MPA were different between Europe and Japan. However, the outcomes of patient survival and renal survival were similar.

Retrospective analysis of factors predicting end-stage renal failure or death in patients with microscopic polyangiitis with mainly renal involvement

BACKGROUND

The aim of this study was to identify risk factors for end-stage renal failure (ESRF) or death in Japanese patients with microscopic polyangiitis (MPA) with renal involvement.

METHODS

From 54 consecutive patients with systemic vasculitis based on Watt's algorithm, we retrospectively analyzed 39 MPA patients with renal involvement, including 19 (48.7 %) with renal-limited vasculitis.

RESULTS

Thirty-three of 39 patients (84.6 %) demonstrated rapidly progressive glomerulonephritis, and 13 (33.3 %) developed ESRF; 8 of 13 required dialysis within 1 week. Thirteen (33.3 %) died during follow-up of more than 12 months, and 7 died during the first 6 months, mainly because of opportunistic infections. Overall survival at 6 and 12 months was 79.5 and 71.1 %, respectively. Serum creatinine levels did not differ significantly between survivors and non-survivors (P = 0.092). The mean Birmingham Vasculitis Activity Score, version 3 (BVAS v.3), was 16.2 ± 6.5, with a renal subscore of over 12 points in 82.1 %, and BVAS v.3 was marginally higher in non-survivors than survivors (P = 0.045). An age- and sex-adjusted Cox proportional hazards analysis demonstrated that neither the serum creatinine level (P = 0.277) nor BVAS v.3 (P = 0.188) at initial diagnosis was a risk factor for overall survival. The baseline serum creatinine cutoff value for discriminating between ESRF and non-ESRF was 4.6 mg/dl, with a sensitivity and specificity of 92.3 and 84.6 %, respectively.

CONCLUSIONS

Survival rates do not relate to ESRF in MPA patients with mainly renal involvement. Although patients with ESRF required regular hemodialysis, longer survival can be achieved.

AP-VAS 2012 case report: MPO-ANCA-negative relapse of MPO-ANCA-associated vasculitis

A 79-year-old female was admitted to our hospital with fever, proteinuria, hematuria, high levels of C-reactive protein (CRP), and high titer of myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA). Our diagnosis was microscopic polyangiitis (MPA) and she was treated with steroid pulse therapy. Clinical remission was induced; however, the disease relapsed with saddle nose and necrotizing vasculitis of the nasal cavity mucosa 1 year later. Although there was no elevation of the MPO-ANCA titer, we diagnosed the patient with relapse of MPO-ANCA-positive granulomatosis with polyangiitis (GPA). Remission was induced again with steroids and azathioprine. It has been reported that the number of MPO-ANCA-positive patients in Asian countries is relatively higher than in Western countries. We checked 29 GPA patients in our hospital and 9 patients (31.0 %) were MPO-ANCA-positive. In addition, it is not rare that an ANCA-associated vasculitis (AAV) patient who has been in remission with negative ANCA relapses without any elevation of ANCA titer. We checked the transition of ANCA titer of 24 AAV patients in our hospital who relapsed and 6 patients (25 %) relapsed without any elevation of ANCA titer. We should be careful for a relapse, even if the ANCA titer remains negative. It is also possible that ANCA had been changed so as not to be detected by the same enzyme-linked immunosorbent assay (ELISA) kit. Thus, it is also important to change the detection system if clinical symptoms are worsened while ANCA is still negative.

Validation of a newly proposed histopathological classification in Japanese patients with anti-neutrophil cytoplasmic antibody-associated glomerulonephritis

Background

A new histopathological classification of anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis was recently proposed. We evaluated the predictive value of this classification for renal outcome in Japanese patients.

Methods

We enrolled 122 patients with ANCA-associated glomerulonephritis diagnosed at several institutions in Japan between January 2000 and March 2010. Twenty patients were excluded because of observation durations of <1 year, and/or because their biopsy specimens contained <10 glomeruli. Renal biopsy specimens were categorized into four classes according to the proposed classification. We evaluated the predictive value of immunohistochemical staining for α-smooth muscle actin (SMA), Wilm’s tumor 1 (WT1), CD68, and cytokeratin for end-stage renal disease (ESRD).

Results

The study population included 54 men and 48 women. Age, estimated glomerular filtration rate (eGFR), and proteinuria were 66.3 ± 11.3 years, 21.6 ml/min. and 1.10 g/24 h, respectively. Eighty-six patients were positive for myeloperoxidase-ANCA, five were positive for proteinase 3-ANCA, and 11 were negative for both antibodies. Median follow-up time was 41.0 months. Twenty-three patients (22.5%) developed ESRD during the follow-up period. Twelve patients died during follow up; 7/12 patients developed ESRD before death, and 5/12 patients died without ESRD. The incidence of ESRD increased with sequential categories: focal, 2/46 (4.3%); crescentic, 9/32 (28%); mixed, 8/18 (44%); and sclerotic, 4/6 (67%). The focal class had the best renal survival and the sclerotic class had the worst renal survival (p < 0.001). Kaplan-Meier renal survival analysis was similar to that of the new classification system proposal. In the multivariate analysis, the classification system tended to be a prognostic factor for ESRD (p = 0.0686, crescentic, mixed and sclerotic vs. focal, hazard ratio (HR) [95% confidence interval, CI]; 2.99 [0.61–22.7], 5.04 [1.11–36.4] and 9.93 [1.53–85.7], respectively). α-SMA-positivity also tended to be associated with ESRD (p = 0.1074).

Conclusion

The new histopathological classification was associated with eGFR at 1 year and tended to be associated with ESRD in our Japanese cohort with ANCA-associated glomerulonephritis. α-SMA positivity might be an additional prognostic factor for ESRD.

De novo acute hepatitis B in myeloperoxidase-specific anti-neutrophil cytoplasmic autoantibody-related microscopic polyangiitis treated with corticosteroids

An 82-year-old female was referred to our hospital because of low-grade fever, anemia, and rapidly progressive nephritic syndrome. Her laboratory data showed mild proteinuria, mild renal failure, and the presence of myeloperoxidase-specific anti-neutrophil cytoplasmic autoantibody. A skin biopsy specimen taken from the erythematous purpura revealed neutrophilic infiltration around the blood vessels with fibrinoid changes in the vessel walls. A renal biopsy specimen revealed segmental necrotizing glomerulonephritis with fibro-cellular crescent formation without deposits of immunoglobulin or complement components, indicating microscopic polyangiitis. The use of corticosteroid treatment, including intravenous methylprednisolone, improved renal failure. After 4 years with low-dose maintenance corticosteroid therapy, she developed de novo acute hepatitis B, and entecavir was remarkably effective, showing a rapid recovery from liver dysfunction with jaundice. To prevent hepatitis B virus (HBV) reactivation and de novo acute hepatitis B induced by immunosuppressive or cytotoxic therapy, including corticosteroids alone, the measurement of HBV-related serological markers needs to be performed prior to the initiation of such therapy, even in renal diseases.

Japan Renal Biopsy Registry and Japan Kidney Disease Registry: Committee Report for 2009 and 2010

The Japan Renal Biopsy Registry (J-RBR) was started in 2007 and the Japan Kidney Disease Registry (J-KDR) was then started in 2009 by the Committee for Standardization of Renal Pathological Diagnosis and the Committee for the Kidney Disease Registry of the Japanese Society of Nephrology. The purpose of this report is to describe and summarize the registered data from 2009 and 2010. For the J-KDR, data were collected from 4,016 cases, including 3,336 (83.1 %) by the J-RBR and 680 (16.9 %) other cases from 59 centers in 2009, and from 4,681 cases including 4,106 J-RBR cases (87.7 %) and 575 other cases (12.3 %) from 94 centers in 2010, including the affiliate hospitals. In the J-RBR, 3,165 native kidneys (94.9 %) and 171 renal grafts (5.1 %) and 3,869 native kidneys (94.2 %) and 237 renal grafts (5.8 %) were registered in 2009 and 2010, respectively. Patients younger than 20 years of age comprised 12.1 % of the registered cases, and those 65 years and over comprised 24.5 % of the cases with native kidneys in 2009 and 2010. The most common clinical diagnosis was chronic nephritic syndrome (55.4 % and 50.0 % in 2009 and 2010, respectively), followed by nephrotic syndrome (22.4 % and 27.0 %); the most frequent pathological diagnosis as classified by the pathogenesis was IgA nephropathy (31.6 % and 30.4 %), followed by primary glomerular diseases (except IgA nephropathy) (27.2 % and 28.1 %). Among the primary glomerular diseases (except IgA nephropathy) in the patients with nephrotic syndrome, membranous nephropathy was the most common histopathology in 2009 (40.3 %) and minor glomerular abnormalities (50.0 %) were the most common in 2010 in native kidneys in the J-RBR. Five new secondary and longitudinal research studies by the J-KDR were started in 2009 and one was started in 2010.

Evaluation of the newly proposed simplified histological classification in Japanese cohorts of myeloperoxidase-anti-neutrophil cytoplasmic antibody-associated glomerulonephritis in comparison with other Asian and European cohorts

The prognostic value of renal biopsy in anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis is widely recognized; however, there is no consensus regarding its pathological classification. Berden et al. proposed a new classification of glomerulonephritis in ANCA-associated vasculitis (AAV) categorized into focal, crescentic, mixed, and sclerotic classes and showed its prognostic value in 100 international multicenter cohorts for 1- and 5-year renal outcomes. In order to evaluate whether this new classification has predictive value and reproducibility in Japanese AAV cases, 87 cohorts with only microscopic polyangiitis in 3 limited centers in Japan were analyzed. In addition, those from Japan, Europe (Berden’s cohorts) and China were compared in a recent report.

Clinical findings on ANCA-associated renal vasculitis from the Japan RPGN registry obtained via a questionnaire survey

Renal involvement with significant organ damage is common in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). As a result, it is independently referred to ANCA-associated renal vasculitis. Clinically, ANCA-associated renal vasculitis is characterized by rapidly progressive glomerulonephritis. Pathologically, it is defined by pauci-immune type necrotizing and crescentic glomerulonephritis. According to previous reports from all over the world, the etiology, prevalence, and prognosis of RPGN including ANCA-associated renal vasculitis varies among races and periods. To elucidate the clinical characteristics of Japanese RPGN patients, a registry derived from a questionnaire survey was established in 1999 and maintained until 2006. As a result, 1,772 cases were collected, analyzed, and reported previously. In this mini-review, we outline the characteristic clinical findings of Japanese patients (Asian) with ANCA-associated renal vasculitis, based on the registry data.