Effectiveness of intravenous methylprednisolone pulse in patients with severe microscopic polyangiitis and granulomatosis with polyangiitis

OBJECTIVES

To evaluate the effectiveness and safety of two different intravenous methylprednisolone (IVMP) pulse doses in patients with severe microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA).

METHODS

We emulated a target trial using observational data from the nationwide registry in Japan. Patients with severe glomerulonephritis or diffuse alveolar haemorrhage were selected and pseudo-randomised into three groups using propensity score-based overlap weighting as follows: non-IVMP, IVMP 0.5 g/day, and IVMP 1.0 g/day. The primary outcome was all-cause death, and the secondary outcomes were composite all-cause death and kidney failure, severe relapse, and serious infection from 2 to 48 weeks after treatment initiation. To estimate the treatment effects, the Cox proportional hazard model and Fine-Gray subdistribution hazard model were used.

RESULTS

In this emulated target trial, of 201 eligible patients (MPA, 175; GPA, 26), 6 (2.8%) died, 4 (2.0%) had kidney failure, 11 (5.3%) had severe relapse, and 40 (19.8%) had severe infections. Hazard ratios (HR) for IVMP 0.5 g/day and IVMP 1.0 g/day pulse groups compared with non-IVMP pulse were as follows: all-cause death = 0.46 (95% confidence interval [95%CI]: 0.07-2.81) and 0.07 (95%CI: 0.01-0.41); all-cause death/kidney failure = 1.18 (95%CI: 0.26-5.31) and 0.59 (95%CI: 0.08-4.52); subdistribution HRs for severe relapse = 1.26 (95%CI: 0.12-13.70) and 3.36 (95%CI: 0.49-23.29); and serious infection = 1.88 (95%CI: 0.76-4.65) and 0.94 (95%CI: 0.28-3.13).

CONCLUSIONS

IVMP 1.0 g/day pulse may improve 48-week mortality in patients with severe MPA/GPA.

High serum IgA levels in patients with IgG4-related disease are associated with mild inflammation, sufficient disease-specific features, and favourable responses to treatments

OBJECTIVES

Although elevated serum immunoglobulin A (IgA) levels are thought to exclude a diagnosis of IgG4-related disease (IgG4-RD), IgG4-RD has been definitively diagnosed in some patients despite elevated serum IgA levels. This study aimed to clarify the prevalence of elevated IgA levels in patients with IgG4-RD and to compare the clinical features of IgG4-RD patients with and without elevated IgA levels.

METHODS

The clinical features of 169 IgG4-RD patients were retrospectively compared among those with and without elevated serum IgA levels.

RESULTS

Of the 169 patients with IgG4-RD, 17 (10.1%) had elevated serum IgA levels. Those with elevated serum IgA levels showed higher serum C-reactive protein levels and lower prevalence of relapse than those without. Other clinical features did not differ significantly, including inclusion scores of the American College of Rheumatology/European League Against Rheumatism classification criteria. Cox regression analysis showed that elevated serum IgA levels were associated with a lower incidence of relapse. Moreover, patients with elevated serum IgA levels showed prompt improvement in response to glucocorticoids in the IgG4-RD responder index.

CONCLUSIONS

Some patients diagnosed with IgG4-RD have high serum IgA levels. These patients may form a subgroup, characterized by good response to glucocorticoids, less frequent relapse, mildly elevated serum C-reactive protein levels, and possible complications of autoimmune diseases.

De novo normotensive scleroderma renal crisis six years after living-donor renal transplantation in a patient with overlapping systemic sclerosis/systemic lupus erythematosus syndrome: a case report

BACKGROUND

Scleroderma renal crisis (SRC) is a critical kidney involvement of systemic sclerosis (SSc), often resulting in end-stage renal disease. Although the recurrence of SRC in the allograft has been reported, the development of de novo SRC after kidney transplantation has not been reported. Furthermore, normotensive SRC, which rarely occurs, makes prompt diagnosis more challenging. This fact should be recognized widely among nephrologists.

CASE PRESENTATION

We report a 37-year-old Japanese man with overlapping SSc/systemic lupus erythematous syndrome who developed normotensive SRC in the transplanted kidney shortly after glucocorticoid escalation. Six years prior to admission, he underwent an ABO-compatible living donor kidney transplantation because of lupus nephritis. He was admitted to our hospital for gradually worsening kidney dysfunction. A kidney biopsy showed idiopathic granulomatous interstitial nephritis and high-dose prednisolone was prescribed. Although renal function improved tentatively, it deteriorated again a week later. A secondary kidney biopsy revealed acute thrombotic microangiopathy, leading to the diagnosis of normotensive SRC because all other causes were excluded, and blood pressure was within normal range. Adding an angiotensin-converting enzyme inhibitor and tapering glucocorticoid slowed the speed of deterioration of his kidney function, but he finally required hemodialysis induction.

CONCLUSIONS

SRC can newly develop even in the transplanted kidney, especially when high-dose glucocorticoid is administered. Normotensive SRC makes the diagnosis challenging, so nephrologists should carefully monitor patients with SSc and transplanted kidneys to treat SRC promptly.

Association between hypogammaglobulinaemia and severe infections during induction therapy in ANCA-associated vasculitis: from J-CANVAS study

OBJECTIVES

To investigate the association between decreased serum IgG levels caused by remission-induction immunosuppressive therapy of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and the development of severe infections.

METHODS

We conducted a retrospective cohort study of patients with new-onset or severe relapsing AAV enrolled in the J-CANVAS registry, which was established at 24 referral sites in Japan. The minimum serum IgG levels up to 24 weeks and the incidence of severe infection up to 48 weeks after treatment initiation were evaluated. After multiple imputations for all explanatory variables, we performed the multivariate analysis using a Fine-Gray model to assess the association between low IgG (the minimum IgG levels <500 mg/dl) and severe infections. In addition, the association was expressed as a restricted cubic spline (RCS) and analysed by treatment subgroups.

RESULTS

Of 657 included patients (microscopic polyangiitis, 392; granulomatosis with polyangiitis, 139; eosinophilic granulomatosis with polyangiitis, 126), 111 (16.9%) developed severe infections. The minimum serum IgG levels were measured in 510 patients, of whom 77 (15.1%) had low IgG. After multiple imputations, the confounder-adjusted hazard ratio of low IgG for the incidence of severe infections was 1.75 (95% confidence interval: 1.03-3.00). The RCS revealed a U-shaped association between serum IgG levels and the incidence of severe infection with serum IgG 946 mg/dl as the lowest point. Subgroup analysis showed no obvious heterogeneity between treatment regimens.

CONCLUSION

Regardless of treatment regimens, low IgG after remission-induction treatment was associated with the development of severe infections up to 48 weeks after treatment initiation.

Clues to mortality trends and their related factors in IgG4-related disease: A Japanese single-centre retrospective study

OBJECTIVES

This study aimed to clarify mortality trends and their related factors in immunoglobulin G4-related disease (IgG4-RD) with various organ involvement.

METHODS

We retrospectively reviewed the medical records of patients with IgG4-RD at a single rheumatology centre in Japan. We calculated the standardized mortality ratio using Japanese national mortality statistics. Cox regression analyses were also performed to assess mortality-related factors.

RESULTS

A total of 179 patients with IgG4-RD were included with a median follow-up period of 47 months. The standardized mortality ratio in our cohort was 0.86 (95% confidence interval 0.41-1.59). Univariate Cox regression analyses indicated that the number of affected organs at diagnosis (hazard ratio 1.45, 95% confidence interval 1.02-2.05), estimated glomerular infiltration rate <45 ml/min/1.73 m2 at diagnosis (vs. ≥45, hazard ratio 8.48, 95% confidence interval 2.42-29.79), and the presence of malignancy during the clinical course (hazard ratio 5.85, 95% confidence interval 1.62-21.15) had a significant impact on the time to death.

CONCLUSIONS

Our findings suggest that in the rheumatology department, IgG4-RD does not significantly affect long-term patient survival. However, multi-organ involvement, renal dysfunction, and malignancy may be associated with higher mortality trends in IgG4-RD. Early detection and appropriate management of risk factors may improve the long-term prognosis of patients with IgG4-RD.

Optimal Dose of Intravenous Cyclophosphamide during remission induction therapy in ANCA-associated vasculitis: a retrospective cohort study of J-CANVAS

OBJECTIVES

To identify the optimal dose of intravenous cyclophosphamide (IVCY) for induction therapy for anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV).

METHODS

We retrospectively assessed patients with AAV who received IVCY every 2-3 weeks during the remission induction phase. The associations of the IVCY dose with infection-free survival and relapse-free survival were analysed using a Cox regression model. We compared patients in three categories: very low-dose (VLD), low-dose (LD), and conventional dose (CD) (<7.5 mg/kg, 7.5-12.5 mg/kg, and >12.5 mg/kg, respectively). The non-linear association between IVCY dose and the outcomes were also evaluated.

RESULTS

Of the 80 patients (median age 72 years), 12, 42, and 26 underwent the VLD, LD, and CD regimens, respectively, of whom 4, 3, and 7 developed infection or died. The adjusted hazard ratios for infection or death were 4.3 (95% confidence interval (CI) 0.94-19.8) for VLD and 5.1 (95% CI 1.21-21.3) for CD, compared with LD. We found the hazard ratio for infection or death increased when the initial IVCY dose exceeded 9 mg/kg. Relapse-free survival did not differ clearly.

CONCLUSION

Low-dose IVCY (7.5-12.5 mg/kg) may result in fewer infections and similar relapse rates compared with the conventional regimen (>12.5 mg/kg).

A Nomogram Based on Pretreatment Radiomics and Dosiomics Features for Predicting Overall Survival for Esophageal Squamous Cell Cancer: Multi-Institutional Study

PURPOSE/OBJECTIVE(S)

The current study aims to propose a nomogram-based 2- and 3-years survival prediction model for esophageal squamous cell carcinoma treated by definitive radiotherapy using pretreatment computed tomography (CT), positron emission tomography (FDG PET) radiomic features and dosiomics features in addition to the common clinical factors using multi-institution data.

MATERIALS/METHODS

Data of 112 patients from one institution and 28 patients from the other institution were retrospectively collected. Radiomics and dosiomics features were extracted using five segmentations on CT and PET images and dose distribution. The least absolute shrinkage and selection operator (LASSO) with logistic regression was used to select radiomics and dosiomics features by calculating the radiomics and dosiomics scores (Rad-score and Dos-score), respectively, in the training model. The predictive clinical factors, Rad-score, and Dos-score were identified to develop a nomogram model.

RESULTS

We extracted 15219 features from the radiomics and dosiomics analysis. By LASSO Cox regression analysis, 13 CT-based radiomics features, 11 PET-based radiomics features, and 19 dosiomics features were selected. Clinical factors of T-stage, N-stage, and clinical stage were selected as significant prognostic factors by univariate Cox regression analysis. A predictive nomogram for prognosis in was established using these factors. In the external validation cohort, the C-index of the combined model of CT-based radiomics, PET-based radiomics, and dosiomics features with clinical factors were 0.74, 0.82, and 0.92, respectively. Moreover, we divided the cohort into high-risk and low-risk groups using the median nomogram score. Significant differences in overall survival (OS) in the combine model of CT-based radiomics, PET-based radiomics, and dosiomics features with clinical factors were observed between the high-risk and low-risk groups (P = 0.019, P = 0.038, and 0.014, respectively).

CONCLUSION

The current study established and validated 2- and 3-year survival prediction models based on radiomics and dosiomics features with clinical factors. The prediction model with dosiomics analysis could better predict OS than CT- and PET-based radiomics analysis in esophageal cancer patients treated with radiotherapy.

Predictive Modeling of Radiation Pneumonitis Induced by Chemoradiotherapy for Locally Advanced Non-Small Cell Lung Cancer Using Radiomics and Clinical Features

PURPOSE/OBJECTIVE(S)

The purpose of this study is to establish a prediction model for the development of grade 2 or higher radiation pneumonitis (RP) using radiomics analysis of pretreatment CT images, PET images, and dose distribution, in addition to clinical factors, in patients with locally advanced non-small cell lung cancer (NSCLC) treated with radical chemoradiotherapy.

MATERIALS/METHODS

We retrospectively evaluated 128 cases of locally advanced NSCLC treated with radical radiotherapy at our institution from 2008 to 2021. Clinical factors included age, sex, performance status (PS), KL-6, smoking history, histological type, clinical stage, and total radiation dose. Radiomics analysis was performed by analyzing treatment planning CT images, PET images, and dose distribution, and Rad-score (Radiomics-score) was calculated for the extracted features using Lasso-Cox regression. Rad-score (Radiomics-score) was calculated by Lasso-Cox regression for the extracted features. Risk factors were selected by univariate/multivariate analysis of clinical factors and Rad-score. Three models for predicting RP were developed from the identified risk factors using Nomogram: Clinical, Rad-score, and Combined model. The model was evaluated using area under the curve (AUC) based on receiver operating characteristic (ROC) curves and concordance index (C-index). RP was evaluated using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. The cumulative incidence of Grade 2 or higher RP was evaluated using the Kaplan-Meier method.

RESULTS

Of the 128 cases, grade 2 or higher RP was observed in 50 cases (39%). Regarding clinical factors, gender, smoking status, and histology were selected as significant predictors of RP. Lasso-Cox analysis of radiomics features selected 11 features from CT images, 7 features from PET images, and 16 features from dose distribution as predictors of RP, yielding a total of 34 factors. The combined model (C-index: 0.96, AUC: 0.92) showed the best discrimination performance compared to the clinical model (C-index: 0.73, AUC: 0.56) and the Rad-score model (C-index: 0.87, AUC: 0.92). Risk classification using the combined model showed that the 1-year cumulative incidence of grade 2 or higher RP was 65% in the high-risk group, significantly higher than 15% in the low-risk group (p<0.001).

CONCLUSION

The combined model with Rad-score and clinical factors can predict grade 2 or higher RP in NSCLC patients with high accuracy.

Seasonal Influence on Development of Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Retrospective Cohort Study Conducted at Multiple Institutions in Japan (J-CANVAS)

OBJECTIVE

To clarify seasonal and other environmental effects on the onset of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

We enrolled patients with new-onset eosinophilic granulomatosis with polyangiitis (EGPA), microscopic polyangiitis (MPA), and granulomatosis with polyangiitis (GPA) registered in the database of a Japanese multicenter cohort study. We investigated the relationship between environmental factors and clinical characteristics. Seasons were divided into 4 (spring, summer, autumn, and winter), and the seasonal differences in AAV onset were analyzed using Pearson chi-square test, with an expected probability of 25% for each season.

RESULTS

A total of 454 patients were enrolled, with a mean age of 70.9 years and a female proportion of 55.5%. Overall, 74, 291, and 89 patients were classified as having EGPA, MPA, and GPA, respectively. Positivity for myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA was observed in 355 and 46 patients, respectively. Overall, the seasonality of AAV onset significantly deviated from the expected 25% for each season (P = 0.001), and its onset was less frequently observed in autumn. In ANCA serotypes, seasonality was significant in patients with MPO-ANCA (P < 0.001), but not in those with PR3-ANCA (P = 0.97). Additionally, rural residency of patients with AAV was associated with PR3-ANCA positivity and biopsy-proven pulmonary vasculitis.

CONCLUSION

The onset of AAV was influenced by seasonal variations and was less frequently observed in autumn. In contrast, the occurrence of PR3-ANCA was triggered, not by season, but by rural residency.

Cardiac light-chain deposition disease and hints at diagnosing: a case report

Background

Light-chain deposition disease (LCDD) is a systemic disorder characterized by non-amyloidotic light-chain deposition in various organs with Bence-Jones type monoclonal gammopathy. Although known as monoclonal gammopathy of renal significance, it may involve interstitial tissue of various organs, and in rare cases, proceeds to organ failure. We present a case of cardiac LCDD in a patient initially suspected of dialysis-associated cardiomyopathy.

Case summary

A 65-year-old man with end-stage renal disease requiring haemodialysis presented with fatigue, anorexia, and shortness of breath. He had a history of recurrent congestive heart failure and Bence-Jones type monoclonal gammopathy. A cardiac biopsy performed for suspected light-chain cardiac amyloidosis was negative for diagnostic Congo-red stain, however, paraffin immunofluorescence examination for light-chain suggested diagnosis of cardiac LCDD.

Discussion

Cardiac LCDD may go undetected leading to heart failure due to lack of clinical awareness and insufficient pathological investigation. In heart failure cases with Bence-Jones type monoclonal gammopathy, clinicians should consider not only amyloidosis but also interstitial light-chain deposition. In addition, in patients with chronic kidney disease of unknown cause, investigation is recommended to rule out cardiac light-chain deposition disease concomitant with renal LCDD. Although LCDD is relatively rare it occasionally affects multiple organs; therefore, it would be better to describe it as a monoclonal gammopathy of clinical significance rather than one of renal significance.

Case report: Rosai-Dorfman disease with rare extranodal lesions in the pelvis, heart, liver and skin

Rosai-Dorfman disease (RDD), a rare form of non-Langerhans cell histiocytosis, can involve systemic extranodal lesions. Skin lesions are the most common, whereas intrapelvic, cardiac, and hepatic lesions are infrequent. The present study describes a 74-year-old woman with multiple extranodal lesions in the pelvis, heart, liver, and skin that were successfully treated with glucocorticoid therapy. She had experienced fever and persistent inflammation without cervical lymphadenopathy for several months and ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed abnormal FDG uptake in the left cheek; cervical, axillary, inguinal lymph nodes; periatrium; and pelvis. She was diagnosed with RDD based on skin and pelvic biopsies. Although this was an atypical case without bilateral cervical lymphadenopathy, the FDG-PET detection of inflammatory lesions led to selection of suitable biopsy sites, and pathological examination led to a correct diagnosis. Findings in this patient indicate that RDD can present with an atypical distribution of infrequent extranodal lesions, with attention required to prevent a delayed diagnosis.

Development of IgG4-related pancreatitis and kidney disease 7 years after the onset of undiagnosed lymphadenopathy: A case report

This report describes a patient diagnosed with immunoglobulin G4 (IgG4)-related pancreatitis and kidney disease 7 years after the onset of undiagnosed lymphadenopathy. A 48-year-old Japanese woman presented with fatigue and leg oedema. Computed tomography showed perigastric lymphadenopathy, for which she underwent a laparoscopic biopsy of the perigastric lymph nodes. Although histopathological examination of the lymph nodes did not lead to a definitive diagnosis, serological tests revealed elevated serum IgG4 levels (558 mg/dl) and IgG4 immunostaining of the lymph nodes showed IgG4-positive plasma cell infiltration, leading to the suspicion of IgG4-related disease. Further workup revealed no organ lesion other than lymphadenopathy. At age 55 years, despite having no subjective symptoms, contrast-enhanced computed tomography showed low-density lesions in the tail of the pancreas and the left kidney. Histopathological examination showed lymphocyte infiltration, consisting of a mixture of plasma cells and eosinophils, in both organs and obliterative phlebitis in the pancreas. IgG4 immunostaining of the kidney specimens showed 160 IgG4-positive cells per high-powered field, with the IgG4+/IgG+ cell ratio being almost 100%, leading to a diagnosis of IgG4-related pancreatitis and kidney disease. Treatment with prednisolone for 2 months resulted in lesion improvement. Although the diagnosis of IgG4-related lymphadenopathy is often challenging in patients with lymphadenopathy alone, findings in the present patient emphasise the importance of long-term follow-up, as it may allow early detection of involvement of other organs by IgG4-related disease.

Association between serum alkaline phosphatase and bacteraemia in haemodialysis outpatients: a multicentre retrospective cross-sectional study

OBJECTIVES

Elevated baseline serum alkaline phosphatase (ALP) may correlate with higher medium-term to long-term mortality in the general population and in patients with chronic kidney disease. However, few data are available on the association between serum ALP and the short-term prognosis of patients on haemodialysis (HD). We verified the association of ALP levels and bacteraemia or death in maintenance HD patients suspected of bacteraemia in an outpatient setting.

DESIGN

We analysed 315 consecutive HD patients suspected of having bacteraemia with two sets of blood culture drawn on admission.

SETTING

Admission to two tertiary-care university medical centres from January 2013 to December 2015.

PARTICIPANTS

Consecutive cases on maintenance HD aged≥18 years. Cases of hospitalised patients who had been transferred from another hospital, had a dialysis vintage<2 months, were also undergoing peritoneal dialysis, and/or were receiving HD less than once a week were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome measure was bacteraemia and secondary outcome was in-hospital death.

RESULTS

Among 315 cases included in the study, 187 had baseline-measured ALP levels, with a cut-off value on ROC analysis of 360 U/L (Area Under the Curve (AUC) 0.60, sensitivity 0.49, specificity 0.76). In multivariate analysis, there was a statistically significant association between a higher ALP in hospital visit and bacteraemia (OR: 2.37, 95% CI: 1.17 to 4.83). However, there were no statistically significant associations between higher ALP and in-hospital death (OR: 1.20, 95% CI: 0.57 to 2.54). A sensitivity analysis of 187 patients with no missing ALP values also demonstrated a significant association between elevated ALP and bacteraemia, but no significant association between ALP and in-hospital death.

CONCLUSIONS

Elevated ALP is a predictor of bacteraemia. In HD patients suspected of bacteraemia in outpatient settings, increased ALP levels were associated with increased likelihood of confirmed disease.

Hypertrophic pachymeningitis in ANCA-associated vasculitis: a cross-sectional and multi-institutional study in Japan (J-CANVAS)

BACKGROUND

This study investigated the characteristics of hypertrophic pachymeningitis (HP) in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), using information from a multicenter study in Japan.

METHODS

We analyzed the clinical information of 663 Asian patients with AAV (total AAV), including 558 patients with newly diagnosed AAV and 105 with relapsed AAV. Clinical findings were compared between patients with and without HP. To elucidate the relevant manifestations for HP development, multivariable logistic regression analyses were additionally performed.

RESULTS

Of the patients with AAV (mean age, 70.2 ± 13.5 years), HP was noted in 30 (4.52%), including 20 (3.58%) with newly diagnosed AAV and 10 (9.52%) with relapsed AAV. Granulomatosis with polyangiitis (GPA) was classified in 50% of patients with HP. A higher prevalence of GPA was significantly observed in patients with HP than in those without HP in total AAV and newly diagnosed AAV (p < 0.001). In newly diagnosed AAV, serum proteinase 3 (PR3)-ANCA positivity was significantly higher in patients with HP than in those without HP (p = 0.030). Patients with HP significantly had ear, nose, and throat (ENT) (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.03-2.14, p = 0.033) and mucous membrane/eye manifestations (OR 5.99, 95% CI 2.59-13.86, p < 0.0001) in total AAV. Moreover, they significantly had conductive hearing loss (OR 11.6, 95% CI 4.51-29.57, p < 0.0001) and sudden visual loss (OR 20.9, 95% CI 5.24-85.03, p < 0.0001).

CONCLUSION

GPA was predominantly observed in patients with HP. Furthermore, in newly diagnosed AAV, patients with HP showed significantly higher PR3-ANCA positivity than those without HP. The ear and eye manifestations may be implicated in HP development.

Evaluating tubulointerstitial compartments in renal biopsy specimens using a deep learning-based approach for classifying normal and abnormal tubules

Renal pathology is essential for diagnosing and assessing the severity and prognosis of kidney diseases. Deep learning-based approaches have developed rapidly and have been applied in renal pathology. However, methods for the automated classification of normal and abnormal renal tubules remain scarce. Using a deep learning-based method, we aimed to classify normal and abnormal renal tubules, thereby assisting renal pathologists in the evaluation of renal biopsy specimens. Consequently, we developed a U-Net-based segmentation model using randomly selected regions obtained from 21 renal biopsy specimens. Further, we verified its performance in multiclass segmentation by calculating the Dice coefficients (DCs). We used 15 cases of tubulointerstitial nephritis to assess its applicability in aiding routine diagnoses conducted by renal pathologists and calculated the agreement ratio between diagnoses conducted by two renal pathologists and the time taken for evaluation. We also determined whether such diagnoses were improved when the output of segmentation was considered. The glomeruli and interstitium had the highest DCs, whereas the normal and abnormal renal tubules had intermediate DCs. Following the detailed evaluation of the tubulointerstitial compartments, the proximal, distal, atrophied, and degenerated tubules had intermediate DCs, whereas the arteries and inflamed tubules had low DCs. The annotation and output areas involving normal and abnormal tubules were strongly correlated in each class. The pathological concordance for the glomerular count, t, ct, and ci scores of the Banff classification of renal allograft pathology remained high with or without the segmented images. However, in terms of time consumption, the quantitative assessment of tubulitis, tubular atrophy, degenerated tubules, and the interstitium was improved significantly when renal pathologists considered the segmentation output. Deep learning algorithms can assist renal pathologists in the classification of normal and abnormal tubules in renal biopsy specimens, thereby facilitating the enhancement of renal pathology and ensuring appropriate clinical decisions.

POS1339 FACTORS RELATED TO SERUM IgG4 ELEVATION AND DEVELOPMENT OF IgG4-RELATED DISEASE: DATA FROM RESIDENT EXAMINATION

Background

Elevated serum IgG4 levels are one of the characteristic findings in immunoglobulin G4 (IgG4)-related disease (IgG4-RD). Serum IgG4 levels have an impact to a certain extent on the diagnosis of IgG4-RD although there are some issues in their sensitivity and specificity. In the reports from Japan, China, USA, and Europe, elevated serum IgG4 levels were reported to be observed in 83-97% of patients with IgG4-RD [1-5]. In the past investigations of hospital patients, some studies reported that 10-15% of hospital patients with elevated serum IgG4 levels had IgG4-RD [6,7]. However, in general adults with no symptom, investigations of prevalence of elevated serum IgG4 levels and/or IgG4-RD have rarely been conducted.

Objectives

This study aimed to investigate the frequency of serum IgG4 elevation in the general Japanese population and its associated factors using data from resident examinations.

Methods

We measured the serum IgG4 levels in 1,204 residents who underwent a general medical examination in Ishikawa prefecture, Japan. Logistic regression analysis was used to search for factors related to elevated serum IgG4 levels. Secondary examinations were conducted for participants in whom elevation was identified.

Results

The mean serum IgG4 level was 44 mg/dL, and elevated serum IgG4 levels were observed in 42 patients (3.5%). Univariate logistic regression analyses showed that male sex, older age, lower estimated glomerular filtration rates based on cystatin C (eGFR-CysC), serum high-density lipoprotein cholesterol levels, and higher hemoglobin A1c (HbA1c) levels were associated with elevated serum IgG4 levels. Subgroup analyses in men showed that older age, lower eGFR-CysC levels, and higher serum HbA1c levels were associated with elevated serum IgG4 levels. In contrast, the analyses in women found no significant factors. One of the 10 residents who underwent secondary examinations was diagnosed with possible IgG4-related retroperitoneal fibrosis.

Conclusion

In the general population, elevated serum IgG4 levels are more common in elderly men, which is similar to the epidemiological features of IgG4-RD.

References

[1]Inoue D, et al. IgG4-related disease: dataset of 235 consecutive patients. Medicine (Baltimore). 2015;94(15):e680.

[2]Yamada K, et al. New clues to the nature of immunoglobulin G4-related disease: a retrospective Japanese multicenter study of baseline clinical features of 334 cases. Arthritis Res Ther. 2017;19(1):262

[3]Culver EL, et al. Elevated serum IgG4 levels in diagnosis, treatment response, organ involvement, and relapse in a prospective IgG4-related disease UK cohort. Am J Gastroenterol 2016;111:733–43.

[4]Lin W, et al. Clinical characteristics of immunoglobulin G4-related disease: a prospective study of 118 Chinese patients. Rheumatology (Oxford). 2015;54(11):1982–90.

[5]Carruthers MN, et al. The diagnostic utility of serum IgG4 concentrations in IgG4-related disease. Ann Rheum Dis 2015;74:14-18.

[6]James Yun, et al. Poor positive predictive value of serum immunoglobulin G4 concentrations in the diagnosis of immunoglobulin G4-related sclerosing disease. Asia Pac Allergy. 2014 Jul;4(3):172-176.

[7]Taiwo N Ngwa, et al. Sreum immunoglobulin G4 ｌevel is a poor predictor of immunoglobulin G4–related disease. Pancreas. 2014 Jul;43(5):704-7.

Disclosure of Interests

None declared

POS0822 HYPERTROPHIC PACHYMENINGITIS IN ANTINEUTROPHIL CYTOPLASMIC ANTIBODY-ASSOCIATED VASCULITIS: A MULTICENTER SURVEY IN JAPAN

Background

Hypertrophic pachymeningitis (HP), characterized by an inflammatory disorder indicating intracranial or spinal thickening of dura mater, is found to develop as a neurological involvement in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Meanwhile, the previous studies focusing on HP in AAV have been reported as a single-institution study, and the analyses were performed in a small number of patients because HP is a rare neurological disorder. Therefore, neither etiological nor clinical characteristics of HP in AAV have been adequately elucidated.

Objectives

This study clarified the characteristics of HP in AAV by analyzing the information of multicenter study in Japan (Japan collaborative registry of ANCA-associated vasculitis: J-CANVAS).

Methods

We analyzed the clinical information from 541 Asian patients with AAV enrolled in J-CANVAS. Of them, newly diagnosed and relapsed AAV were included in 448 and 93, respectively. The epidemiological and clinical findings were compared between patients with and without HP. Clinical manifestations related to AAV were evaluated based on the Birmingham Vasculitis Activity Score version 3. To elucidate independent factors in HP development, logistic regression analyses were additionally performed.

Results

Of the total 541 patients (mean age: 71±14 years, M:F = 1:1.2), HP was demonstrated in 28 (5.17%), including 17 (3.79%) in newly diagnosed AAV and 11 (11.8%) in relapsed AAV. The classification of granulomatosis with polyangiitis (GPA) was significantly higher in patients with HP than those without HP (50% vs. 21%, p = 0.0007). In newly diagnosed AAV, patients with HP significantly had higher GPA classification and higher positivity for PR3-ANCA than those without HP (53% vs. 17%, p = 0.001; 29% vs. 9%, p = 0.015, respectively). Conversely, positivity for MPO-ANCA was significantly higher in patients with HP than those without HP in relapsed AAV (91% vs. 55%, p = 0.025), despite not significantly different in the classification of AAV. Headache and cranial neuropathies were significant neurological symptoms in patients with HP compared to those without HP (82% vs. 6.6%, p < 0.0001; 32% vs. 2.9%, p < 0.0001, respectively). Besides, ear, nose and throat (ENT) and mucous membranes/eyes were significantly higher involvements in patients with HP than in those without HP (54% vs. 26%, p = 0.003; 29% vs. 9%, p = 0.003, respectively). Moreover, higher complications of “conjunctive hearing loss” and “sudden visual loss”, which are included in the categories of ENT and mucous membranes/eyes involvement, respectively, were significantly indicated in patients with HP than those without HP (39% vs. 7.2%, p < 0.0001; 21% vs. 1.2%, p < 0.0001, respectively). Multivariable logistic regression analysis identified that ENT (odds ratio [OR] 1.28, 95% confident interval [CI] 1.09 to 1.49, p = 0.002) and mucous membranes/eyes involvement (OR 1.37, CI 1.14 to 1.65, p = 0.0006), as well as conjunctive hearing loss (OR 4.52, CI 1.56 to 13.05, p = 0.005) and sudden visual loss (OR 1.84, CI 1.12 to 3.00, p = 0.015), were independent related factors in patients with HP.

Conclusion

GPA could be significantly classified in patients with HP. Notably, patients with HP significantly showed higher positivity for PR3-ANCA than those without HP in newly diagnosed AAV. Furthermore, sudden visual loss and conjunctive hearing loss might be implicated in HP development.

Disclosure of Interests

None declared

AB0625 Association between Cytomegalovirus Reactivation and Renal Prognosis during Remission Induction Therapy for ANCA-Associated Vasculitis

Background

Cytomegalovirus (CMV) has been associated with atherosclerosis in patients with chronic renal failure, and may cause secondary nephrotic syndrome. Therefore, we hypothesized that the reactivation of CMV by immunosuppressive therapy in patients with vasculitis may affect renal function.

Objectives

The purpose of this study was to investigate relationships between CMV infection and renal function during ANCA-associated vasculitis remission induction therapy.

Methods

This retrospective cohort study enrolled microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis patients at 25 sites in Japan who had a first or severe relapse between January 2017 and June 2020. Of these, patients with MPA or GPA who had a positive renal lesion score on BVAS (version 3) at baseline, or vasculitis findings on renal biopsy, CMV assayed by 48 weeks of treatment, were included. Patients were divided into two groups based on the presence or absence of a positive CMV antigen test during the remission induction phase (0–48 weeks of treatment). Outcomes were the rate of change in estimated glomerular filtration rate (eGFR) at 48 weeks after initiation of treatment in both groups, as determined by (eGFR at 48 weeks - eGFR at the initiation of treatment)/eGFR at the initiation of treatment; where lower values were associated with worse renal function. General linear models adjusted for age, gender, presence of diabetes or chronic kidney disease, and the use of rituximab or cyclophosphamide were generated.

Results

A total of 387 patients had CMV antigen measured during ANCA-associated vasculitis treatment, of which 164 had renal involvement and eGFR measured at 48 weeks. Seventy-seven (47.0%) were male and the median age was 75 years (range 69–80 years). CMV reactivation was observed in 44 patients (26.8%). The beta coefficient of multiple regression analysis with CMV positive as 1 and negative as 0 was 0.08 (95% confidence interval -0.13 to 0.29) (p = 0.47). The rate of change in eGFR was higher in the CMV positive group, but not statistically significantly.

Conclusion

Contrary to our hypothesis, renal prognoses tended to be better when CMV reactivation was observed. The patients in the CMV reactivation group may have been treated more aggressively, and some patients with a poor prognosis who were not followed up for 48 weeks dropped out. Further research investigating the adjustment of treatment methods is required.

Disclosure of Interests

None declared

POS0247 GLUCOCORTICOID TAPERING STRATEGY FOR ANCA-ASSOCIATED VASCULITIS: ADDRESSING THE GAP BETWEEN RECOMMENDATIONS AND REAL-WORLD PRACTICE

Background

Antineutrophil cytoplasmic antibody -associated vasculitis (AAV) is usually treated with combination of high-dose glucocorticoid (GC) and immunosuppressive agents, followed by tapering GC dose. Although the European League Against Rheumatism (EULAR) has specific recommendations for tapering the GC dose, clinicians often taper it slower than recommended due to concerns of potential disease relapse. However, such slower taper may prolong GC exposure for the patients, increasing the risk of adverse events, particularly infection.

Objectives

The aims of our study were (1) to clarify GC dose tapering in the treatment of AAV in a real-world setting, in contrast to the EULAR recommendation of 2015 and (2) to compare the incidence of AAV relapse and severe infection between patients underdoing EULAR-recommended tapering and those undergoing slower tapering than the recommendation.

Methods

In this multicenter (25 sites in Japan), observational, retrospective study of AAV, 541 patients who had initial or severe relapse were enrolled between January 2017 and June 2020. Of these, 349 patients with microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA) who entered in GC tapering phase after successful induction treatment were included. These patients were then grouped on the pace of GC tapering, defined as the GC dose at 12 weeks after treatment initiation: (1) EULAR group: 7.5-10 mg/day of GC, according to the EULAR recommendation of 2015, and (2) SLOWER group: >10 mg/day of GC. Their baseline characteristics and clinical outcomes were compared. Primary outcome was defined as relapse-free days from treatment initiation, whereas secondary outcome included the incidence of infectious events requiring hospitalization within 48 weeks from treatment initiation. Multivariable analysis was performed to assess the relationship between tapering pace and clinical outcomes.

Results

There were 44 patients (12.6%) in the EULAR group and 290 (83.2%) in the SLOWER group. Regarding baseline characteristics, compared with the EULAR group, the SLOWER group had significantly higher serum C-reactive protein level (EULAR, 5.89 ± 6.89 mg/dL vs SLOWER, 7.56 ± 6.01 mg/dL; p = 0.03), as well as a trend toward higher Birmingham Vasculitis Activity Score (version 3) (EULAR, 11.80 ± 7.01 SLOWER, 13.93 ± 7.06; p = 0.08) We did not observe any significant differences in the frequency of relapses between the two groups (EULAR, 8/44, 18.2% vs SLOWER, 55/290, 19.0%; p = 0.63). Multivariable Cox proportional hazard analysis revealed no relationship GC dose at 12 weeks from treatment initiation and incidence of relapse. However, upon logistic regression analysis, the SLOWER group was found to have significant higher risk of a severe infectious event within 48 weeks from treatment initiation (p = 0.046; hazard ratio, 1.27; 95% confidence interval, 1.004 – 1.601).

Conclusion

Our finding indicates that clinicians tended to taper GC slower for patients with higher disease activity. However, slower GC taper was not found to reduce the frequency of relapse. In addition, slower GC taper was found to increase the risk of a severe infection. Hence, clinicians should pay attention not only relapsing but also late GC taper resulting in the risk of serious infection, especially in patients with higher disease activity of AAV.

References

[1]Eur J Clin Invest 2015;45 (3): 346–368.

[2]Rheumatology (Oxford). 2021 Dec 24;61(1):205-212.

[3]Arthritis Res Ther. 2021 Mar 20;23(1):90.

[4]Scand J Rheumatol. 2022 Jan 20;1-13.

[5]J Rheumatol. 2018 Apr;45(4):521-528.

[6]Rheumatol Adv Pract. 2021 Mar 9;5(3):rkab018.

[7]Ann Rheum Dis. 2016 Sep;75(9):1583-94.

Figure 1.

Acknowledgements

We would like to thank Editage (www.editage.com) for English language editing.

Disclosure of Interests

None declared

Urinary abnormality in mixed connective tissue disease predicts development of other connective tissue diseases and decrease in renal function

OBJECTIVE

To clarify the clinical significance of development of urinary abnormality in mixed connective tissue disease (MCTD).

METHODS

Forty-one patients with an initial diagnosis of MCTD, followed at five hospitals between April 1, 2000 and December 31, 2013, were included. The relationship between urinary abnormality and various clinical parameters were retrospectively analyzed. Urinary abnormality was defined as proteinuria and/or hematuria detected by urinalysis. Development of other connective tissue diseases (CTDs) was defined as satisfaction of the criteria of each respective disease.

RESULTS

Of 41 patients (34 females, 7 males, mean age at diagnosis 42.2 ± 15.2 years), 16 developed urinary abnormality (UrA(+) patients). The total incidences of development of other CTDs were higher in the UrA(+) patients than UrA(-) (62.5% versus 16.0%, p = .01). In the comparison between UrA(+) and UrA(-) patients, there were no significant differences in follow-up duration or last determined estimated glomerular filtration rate (eGFR), although eGFR decreased more significantly in the UrA(+) patients than UrA(-). (-20.2 ± 17.2 vs -6.1 ± 13.8 ml/min/1.73m2, p = .01; -21.0 ± 18.9 vs -6.7 ± 14.1%, p = .03).

CONCLUSION

Urinary abnormality during the clinical course in MCTD is predictive of a higher incidence of developing other CTDs. Furthermore, it might also predict long-term renal prognosis in patients with an initial diagnosis of MCTD.

Positive disease-specific autoantibodies have limited clinical significance in diagnosing IgG4-related disease in daily clinical practice

OBJECTIVES

The 2019 ACR/EULAR classification criteria for IgG4-related disease (IgG4-RD) have exclusion criteria including positive disease-specific autoantibodies, and these have been documented to have a high specificity. This study aimed to further validate these criteria as well as identify characteristics of patients showing false-negative results.

METHODS

We retrospectively analysed 162 IgG4-RD patients and 130 mimickers. The sensitivity, specificity and fulfilment rates for each criterion were calculated, and intergroup comparisons were performed to characterize the false-negative cases.

RESULTS

Both the IgG4-RD patients and mimickers were aged ≥65 years with male predominance. The final diagnoses of mimickers were mainly malignancy, vasculitis, sarcoidosis and aneurysm. The classification criteria had a sensitivity of 72.8% and specificity of 100%. Of the 44 false-negative cases, one did not fulfil the entry criteria, 20 fulfilled one exclusion criterion and 27 did not achieve sufficient inclusion criteria scores. The false-negative cases had fewer affected organs, lower serum IgG4 levels, and were less likely to have received biopsies than the true-positive cases. Notably, positive disease-specific autoantibodies were the most common exclusion criterion fulfilled in 18 patients, only two of whom were diagnosed with a specific autoimmune disease complicated by IgG4-RD. In addition, compared with the true-positive cases, the 18 had comparable serum IgG4 levels, number of affected organs, and histopathology and immunostaining scores despite higher serum IgG and CRP levels.

CONCLUSIONS

The ACR/EULAR classification criteria for IgG4-RD have an excellent diagnostic specificity in daily clinical practice. Positive disease-specific autoantibodies may have limited clinical significance for the diagnosis of IgG4-RD.

AB0760 HIGH SERUM IGA LEVELS HAVE LIMITED CLINICAL SIGNIFICANCE IN PATIENTS WITH IGG4-RELATED DISEASE DIAGNOSED BY EXPERTS

Background:

While the diagnostic and classification criteria for IgG4-related disease (IgG4-RD) have been recently developed [1-3], it is known that, without appropriate exclusions, some non-IgG4-RDs may meet these criteria. In particular, hyper IL-6 syndromes, including Castleman disease, can be misdiagnosed as IgG4-RD. Some clinical findings, including elevated serum levels of C-reactive protein (CRP) or IgA, have been suggested to be useful for differentiating hyper IL-6 syndromes from IgG4-RD [4]. However, since few clinical studies have focused on IgG4-RD with high serum IgA levels, its clinical significance has not been well known.

Objectives:

This study aimed to clarify the clinical significance of high serum IgA levels in patients with IgG4-RD.

Methods:

We retrospectively investigated the clinical features of 170 patients with IgG4-RD on the basis of the presence or absence of elevated serum IgA levels (>410 mg/dL) at the time of diagnosis. The diagnosis of IgG4-RD was made by experts on the basis of the fulfillment of the comprehensive diagnostic criteria and/or each organ-specific diagnostic criteria.

Results:

Elevated serum IgA levels were observed in 18 patients (10.6%). In the patients with elevated serum IgA levels, serum CRP levels were higher (1.14 ± 1.18 vs. 0.31 ± 0.63 mg/dL, p=0.003) and the prevalence of relapse during the clinical course was lower (5.6% vs. 27.6%, p=0.046) than in those without elevated serum IgA levels. However, there were no significant differences in the other clinical features including the number of involved organs (2.4 ± 1.3 vs. 2.8 ± 1.6, p=0.443) and inclusion scores of the ACR/EULAR classification criteria (32 ± 14 vs. 36 ± 17, p=0.374). To evaluate the influence of serum IgA elevation on relapse, we performed Cox regression analysis, which showed that the elevated serum IgA levels had no significant association with lower incidence of relapse but a tendency of it (hazard ratio 0.997, 95% confidence interval 0.994-1.000, p=0.055) during the clinical course. In addition, a prompt improvement in the IgG4-RD responder index [5] during the clinical course was seen in the patients with serum IgA elevation, suggesting a similar good response to glucocorticoids as in those without it.

Conclusion:

The findings of the present study suggest that IgG4-RD patients with high serum IgA levels can be diagnosed and treated in the same way as those without it, although they may be characterized by mild serum CRP elevation.

References:

[1]Wallace ZS et al. The 2019 American College of Rheumatology/European League Against Rheumatism classification criteria for IgG4-related disease. Ann Rheum Dis. 2020;79:77-87.

[2]Umehara H et al. The 2020 Revised Comprehensive Diagnostic (RCD) Criteria for IgG4-RD. Mod Rheumatol. 2020 Dec 4:1-14. doi: 10.1080/14397595.2020.1859710. Online ahead of print.

[3]Umehara H et al. Current approach to the diagnosis of IgG4-related disease - Combination of comprehensive diagnostic and organ - specific criteria. Mod Rheumatol. 2017;27:381-91.

[4]Sato Y et al. Systemic IgG4-related lymphadenopathy: A clinical and pathologic comparison to multicentric Castleman’s disease. Mod Pathol.2009;22:589-99.

[5]Carruthers MN et al. Development of an IgG4-RD Responder Index. Int J Rheumatol. 2012;2012:259408.

Disclosure of Interests:

None declared

POS1348 MORTALITY AND ITS RELATED FACTORS IN PATIENTS WITH IGG4-RELATED DISEASE: A JAPANESE SINGLE-CENTER STUDY

Background:

In recent years, IgG4-related disease (IgG4-RD) has become a widely recognized disorder. However, mortality and its related factors in this disease are not well known.

Objectives:

This study aimed to clarify mortality and its related factors in patients with IgG4-RD.

Methods:

We retrospectively reviewed the medical records of patients with IgG4-RD diagnosed by experts based on fulfillment of the Japanese comprehensive diagnostic criteria and/or the 2019 ACR/EULAR classification criteria for IgG4-RD at a single center in Japan. Using the collected data, we calculated the crude mortality rate and the standardized mortality ratio (SMR) using national Japan mortality statistics and investigated the cause of death. We performed Cox regression analyses to assess mortality-related factors.

Results:

A total of 179 patients with IgG4-RD were included: 124 were male (69.3%); the median age was 68 years (interquartile range [IQR] 60-75 years); and the median follow-up from diagnosis was 47 months (IQR 17-84). Ten patients (5.6%) in our cohort died during the follow-up period. Five died of malignancy, one of respiratory failure, two of infectious pneumonia, one of sudden cardiac event, and one of suspected aortic aneurysmal rupture. The crude mortality rate was 11.1 per 1,000 person-years. According to national Japan mortality statistics, 11.6 age- and sex-matched deaths were expected to occur within the follow-up period, resulting in a SMR of 0.86 (95% confidence interval [CI] 0.41-1.59). Univariate Cox regression analyses indicated that the number of affected organs at diagnosis (hazard ratio [HR] 1.45, 95% CI 1.02-2.05), serum creatinine levels at diagnosis (HR 1.82, 95% CI 1.06-3.12), and the presence of malignancy during the clinical course (HR 3.93, 95% CI 1.10-14.02) had a significant impact on the time to death, whereas the other factors including age at diagnosis and serum C-reactive protein and IgG4 levels at diagnosis did not.

Conclusion:

Our findings suggest that the mortality rate of patients with IgG4-RD does not significantly differ from that of the Japanese general population. Multi-organ involvement and renal dysfunction at diagnosis as well as malignancy during the clinical course may be associated with higher mortality. An appropriate clinical evaluation for the early detection of these risk factors is required at first diagnosis and during long-term follow-up.

Disclosure of Interests:

None declared

Glomerulonephritis with severe nephrotic syndrome induced by immune complexes composed of galactose-deficient IgA1 in primary Sjögren's syndrome: a case report

BACKGROUND

Primary Sjögren's syndrome (pSS) is an auto-immune disease characterized by sialadenitis and dacryoadenitis with lymphoplasmacytic cell infiltration. In pSS, not only sicca symptoms, but also extra-glandular involvement induced by immune abnormalities based on pSS occurs. Renal involvement is one such important life-threatening extra-glandular involvement. Although the aberrant glycosylated IgA in pSS as a product of over-activated B cells is a risk factor of renal involvement, its association has not been clarified. Here we report a case of glomerulonephritis (GN) induced by immune complexes (IC) composed of galactose-deficient IgA1 (Gd-IgA1) in a patient with pSS.

CASE PRESENTATION

A 48-year-old Japanese woman with pSS was admitted to our hospital because of a two-month history of nephrotic syndrome. Seven years before she had been diagnosed with pSS from keratoconjunctivitis sicca, elevation of serum anti-Ro/SSA antibody titer and lymphoplasmacytic cell infiltration around salivary ducts of the small salivary glands. Renal biopsy revealed diffuse bubbling appearance in glomerular basement membrane (GBM) with scarce mesangial proliferation. Immunofluorescence showed granular IgA, C3 and Gd-IgA1 staining of GBM. Light chain staining showed no monoclonality. Electron microscopy showed electron dense deposits mainly in the intra-membranous and paramesangial areas and slightly in the subepithelial area. Additional serum analysis confirmed elevation of Gd-IgA1 (13.5 μg/mL), which was comparable with that seen in IgA nephropathy, and qualitative enzyme-linked immunosorbent assay of IgA-containing circulating immune complex (IgA-CIC) was positive. Thus, we diagnosed GN induced by IC composed of Gd-IgA1. Furthermore, retrospectively performed immunofluorescence of the small salivary gland evaluated at the diagnosis of pSS showed positive Gd-IgA1 staining of infiltrating lymphoplasmacytic cells. Therefore, we concluded that Gd-IgA1 produced by over-activated B cells in pSS formed circulating IC and thereby induced GN. After induction therapy with high dose prednisolone and mycophenolate mofetil, the nephrotic syndrome remitted within 3 weeks, the serum Gd-IgA1 level decreased to the normal range (3.8 μg/mL), and serum IgA-CIC disappeared in the 6th month after induction therapy.

CONCLUSIONS

Our findings clearly demonstrate an association between aberrant glycosylated IgA and the renal involvement seen in pSS, thereby helping to clarify the renal significance of aberrant glycosylated IgA in pSS.

Tertiary lymphoid tissue in early-stage IgG4-related tubulointerstitial nephritis incidentally detected with a tumor lesion of the ureteropelvic junction: a case report

Background

IgG4-related kidney disease causes renal impairment of unknown pathogenesis that may progress to kidney failure. Although ectopic germinal centers contribute to the pathogenesis of the head and neck lesions of IgG4-related disease, the presence of tertiary lymphoid tissue (TLT) containing germinal centers in IgG4-RKD has rarely been reported.

Case presentation

We report a 72-year-old Japanese man who had IgG4-related tubulointerstitial nephritis (TIN) with TLT formation incidentally detected in a resected kidney with mass lesion of IgG4-related ureteritis in the ureteropelvic junction. During follow-up for past surgical resection of a bladder tumor, renal dysfunction developed and a ureter mass was found in the right ureteropelvic junction, which was treated by nephroureterectomy after chemotherapy. Pathology revealed no malignancy but abundant IgG4-positive cell infiltration, obliterative phlebitis and storiform fibrosis, confirming the diagnosis of IgG4-related ureteritis. In the resected right kidney, lymphoplasmacytes infiltrated the interstitium with focal distribution in the renal subcapsule and around medium vessels without storiform fibrosis, suggesting the very early stage of IgG4-TIN. Lymphocyte aggregates were also detected at these sites and consisted of B, T, and follicular dendritic cells, indicating TLT formation. IgG4-positive cells infiltrated around TLTs.

Conclusions

Our case suggests that TLT formation is related with the development of IgG4-TIN and our analysis of distribution of TLT have possibility to elucidate IgG4-TIN pathophysiology.

SAT0532 POSITIVE DISEASE-SPECIFIC AUTOANTIBODIES LOWER DIAGNOSTIC SENSITIVITY BUT HAVE LITTLE CLINICAL SIGNIFICANCE IN DIAGNOSING IgG4-RELATED DISEASE USING THE 2019 ACR/EULAR CLASSIFICATION CRITERIA IN DAILY CLINICAL PRACTICE

Background:

Recently, the 2019 ACR/EULAR classification criteria for IgG4-related disease (IgG4-RD) were published mainly to identify more homogeneous subjects for inclusion in clinical trials and observational studies [1]. However, although their high specificity is presumed to be useful to differentiate IgG4-RD from various mimickers, their value in daily clinical practice needs to be evaluated.

Objectives:

This study aimed to clarify the usefulness of the 2019 ACR/EULAR classification criteria for IgG4-RD and characteristics of false-negative patients in daily clinical practice.

Methods:

We retrospectively reviewed the medical records of 162 patients with IgG4-RD and 130 consecutive non-IgG4-RD patients (mimickers) diagnosed by experts whose serum IgG4 levels were measured at a single center in Japan. Using the collected data, we calculated sensitivity, specificity, and fulfillment rates for the entry criteria, exclusion criteria, and threshold of inclusion criteria points. In addition, to clarify the characteristics of false-negative cases in IgG4-RD, we performed an intergroup comparison of their clinical features including disease-specific autoantibodies.

Results:

Both the patients with IgG4-RD and mimickers were relatively old (66 and 65 years) with male predominance (67% and 60%). The final diagnoses of mimickers mainly consisted of cancer, lymphoma, vasculitis, sarcoidosis, multicentric Castleman’s disease, and atherosclerotic or infectious aortic aneurysm. The classification criteria had a sensitivity of 72.8% and a specificity of 100%. Of the 44 false-negative cases, one did not fulfill the entry criteria, 20 fulfilled one exclusion criterion, and 27 did not achieve sufficient inclusion criteria points. Compared with the true-positive cases, the false-negative cases had significantly fewer affected organs, lower serum IgG4 levels, higher serum CH50 levels, and lower prevalence of salivary/lacrimal gland and renal parenchymal lesions. They were also less likely to have had biopsies (61% vs 97%). Of note, positivity of disease-specific autoantibodies including SSA/Ro antibody, ANCA, ds-DNA antibody, and ACPA was the most common exclusion criterion fulfilled in 18 patients, only 2 of whom were diagnosed with a specific autoimmune disease (rheumatoid arthritis) complicated by IgG4-RD. The remaining 16 patients had no specific clinical symptoms related to such autoantibodies. In addition, compared with IgG4-RD patients without disease-specific autoantibodies, the 18 patients with them had almost equal serum IgG4 and complement levels, number of affected organs, and histopathology and immunostaining scores despite higher serum IgG and CRP levels.

Conclusion:

The present study suggests that the 2019 ACR/EULAR classification criteria for IgG4-RD has excellent diagnostic specificity and moderate sensitivity in daily clinical practice. Positive disease-specific autoantibodies alone, which lowered the sensitivity in this study, may have little clinical significance concerning the diagnosis of IgG4-RD.

References:

[1]Wallace ZS et al. The 2019 American College of Rheumatology/European League Against Rheumatism classification criteria for IgG4-related disease. Ann Rheum Dis. 2020 Jan;79(1):77-87.

Disclosure of Interests:

None declared

Wire-loop lesion is associated with serological immune abnormality, but not renal prognosis, in lupus nephritis

BACKGROUND

Wire-loop lesion (WL) is one of the active lesions of lupus nephritis (LN). However, few reports have focused on the clinicopathological relationships of WL to serological immune abnormality and renal prognosis.

METHODS

We enrolled 126 Japanese LN patients subjected to renal biopsy in 11 hospitals from 2000 to 2018. In patients with class III or IV of the International Society of Nephrology/Renal Pathology Society classification, we retrospectively compared clinicopathological findings between those with WL (WL+ group) and without WL (WL- group) to detect factors associated with WL. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate of <60 mL/min/1.73m² for more than three months. We also compared these findings between those with CKD (CKD+ group) and without CKD (CKD- group) at the last visit to investigate factors associated with renal prognosis.

RESULTS

Of 126 patients, 100 (79.4%) were classified as class III or IV. WL was found in 36 (36.0%) of them. Although the renal function did not differ, the WL+ group had a higher titre of serum anti-dsDNA antibodies and lower serum complement 3 levels than the WL- group. Linear regression analysis revealed a significant association only between anti-dsDNA antibodies and WL (β = 0.27, 95% confidence interval (CI) 0.001-0.100, p = 0.01). Of these patients, 69 were tracked for 59.6 ± 55.1 months. Kaplan-Meier analysis showed no difference in renal prognosis between these groups. Next, the CKD+ group included 15 (22.1%) patients. They were older and had higher frequencies of hypertension and hyperuricaemia, serum creatinine (Cr) level, glomerulosclerosis, interstitial inflammation, interstitial fibrosis and tubular atrophy than the CKD- group at the time of renal biopsy. The frequency of WL was not significantly different. Cox regression analysis revealed significant associations of CKD with hypertension, hyperuricaemia, serum Cr level at the time of renal biopsy clinically and with tubular atrophy histologically.

CONCLUSIONS

WL was associated with serum anti-dsDNA antibodies but not with renal prognosis, suggesting that WL reflects immune abnormality but is not an independent factor predictive of renal prognosis in LN.

A phantom study investigating the relationship between ground-glass opacity visibility and physical detectability index in low-dose chest computed tomography

In this study, the relationship between ground‐glass opacity (GGO) visibility and physical detectability index in low‐dose computed tomography (LDCT) for lung cancer screening was investigated. An anthropomorphic chest phantom that included synthetic GGOs with CT numbers of ‐630 Hounsfield units (HU; high attenuation GGO: HGGO) and ‐800 HU (low attenuation GGO: LGGO), and three phantoms for physical measurements were employed. The phantoms were scanned using 12 CT systems located in 11 screening centers in Japan. The slice thicknesses and CT dose indices (CTDIvol) varied over 1.0–5.0 mm and 0.85–3.30 mGy, respectively, and several reconstruction kernels were used. Physical detectability index values were calculated from measurements of resolution, noise, and slice thickness properties for all image sets. Five radiologists and one thoracic surgeon, blind to one another's observations, evaluated GGO visibility using a five‐point scoring system. The physical detectability index correlated reasonably well with the GGO visibility (R2=0.709,p<0.01 for 6 mm HGGO and R2=0.646,p<0.01 for 10 mm LGGO), and was nearly proportional to the CTDI_vol. Consequently, the CTDIvol also correlated reasonably well with the GGO visibility (R2=0.701,p<0.01 for 6 mm HGGO and R2=0.680,p<0.01 for 10 mm LGGO). As a result, the CTDIvol was nearly dominant in the GGO visibility for image sets with different reconstruction kernels and slice thicknesses, used in this study.

PACS numbers: 81.70.Tx, 87.57.Q‐

EXpression of ErbB proteins in human prostate

ErbB proteins are widely expressed in human and animal tissues, notably in cells of epithelial or neuroendocrine origin. Protein expression and interactions of ErbBs were examined in prostate cancer specimens. Expression of ErbB1-4 proteins was determined with immunohistochemical methods using each monoclonal antibody in 20 prostatic adenocarcinomas. The 4 ErbB proteins were widely expressed in normal, hyperplastic and cancerous tissues of the prostate. ErbBs may contribute to normal development or tumor growth and progression in human prostate.

Effects of lithium on endolymph homeostasis and experimentally induced endolymphatic hydrops

There is evidence to suggest that water homeostasis in the inner ear is regulated via the vasopressin (VP)-aquaporin 2 (AQP2) system in the same fashion as in the kidney. The VP-AQP2 system in the kidney is well known to be inhibited by lithium, resulting in polyuria due to a decrease in reabsorption of water in the collecting duct of the kidney. Therefore, lithium is also likely to inhibit the VP-AQP2 system in the inner ear, and consequently exert some influence on inner ear fluid homeostasis. In this study, we investigated the effects of lithium on AQP2 expression in the rat inner ear, and on the cochlear fluid volume in hydropic ears of guinea pigs. A quantitative PCR study revealed that lithium reduced AQP2 mRNA expression in the cochlea and endolymphatic sac. Lithium application also decreased the immunoreactivity of AQP2 in the cochlea and endolymphatic sac. In a morphological study, lithium intake significantly reduced endolymphatic hydrops dose-dependently. These results indicate that lithium acts on the VP-AQP2 system in the inner ear, consequently producing a dehydratic effect on the endolymphatic compartment.

Preparation and evaluation of new Pirkle type chiral stationary phases with long alkyl chains for the separation of amino acid enantiomers derivatized with NBD-F

In order to improve the high-performance liquid chromatographic separation of alpha-amino acids derivatized with the fluorogenic reagent 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) on commercially available chiral stationary phases (CSPs) such as SUMICHIRAL OA-2500(S) (CSP 1) and OA-4700 (CSP 3), the preparation of two new CSPs (CSP 2 and CSP 4) having 11-aminoundecanoic acid between the aminopropyl silica gel support and the chiral moiety in CSP 1 and CSP 3 is described. CSP 2 and CSP 4 improved both the mutual and enantiomeric separation of NBD-amino acids compared with CSP 1 and CSP 3. Thus, 17 pairs of NBD-amino acid enantiomers and NBD-glycine were separated on CSP 2 except for six NBD-amino acids (D-Asn, D-Ser, D-Gln, L-Pro, L-Ser and Gly). CSP 2 and CSP 4 also showed better enantiomeric separation of NBD-amino acid esters and amides than CSP 1 and CSP 3. It was considered that the achiral long alkyl chains in the CSPs might form a hydrophobic space which assisted the stereoselective interaction of analytes with the chiral moiety by changing the environment around the chiral moiety. On CSP 1 and CSP 2, NBD-beta-amino acid was also enantiomerically separated.

Determination of triazolam in serum by deactivated metal capillary gas chromatography with electron-capture detection

A method for the determination of trace amounts of triazolam in serum by deactivated metal capillary gas chromatography with electron-capture detection was established. The column used exhibits excellent thermostability in high-temperature analysis and easy handling and a long lifetime of the column and well shaped peaks on the chromatograms are obtained. With the metal capillary column, it was found to be easier to maintain suitable analytical conditions for the routine assay of triazolam than with a fused-silica column. With this method, 0.5 ng/ml of triazolam in serum can be determined. The method is useful for pharmacokinetic and therapeutic purposes.

[Hypertrophic cranial pachymeningitis with propionibacterium acnes detected by dural biopsy]

A 30-year-old woman experienced recurrent dull headache and frequent partial motor seizure (Jacksonian type) that marched from right fingers. This motor seizure was uncontrollable with ordinary anticonvulsant therapy. Cerebrospinal fluid showed mild pleocytosis. Cranial CT examination was unremarkable, but MRI revealed thickened dural lesion on the left fronto-parietal site, giving diagnosis of hypertrophic cranial pachymeningitis. Dural biopsy showed nonspecific chronic granulomatous state without specific granuloma such as tuberculosis nor sarcoidosis. Anaerobic culture revealed Propionibacterium acnes, a rare causative agent of meningitis. We conclude that it is important to follow a case of unknown cause pachymeningitis carefully with MRI, and in some cases, is required a dural biopsy to make a diagnosis before steroid therapy.

T-cell acute lymphoblastic leukemia with transient pure red cell aplasia associated with myasthenia gravis and invasive thymoma

A 43-year-old male developed rapidly progressing anemia and a bone marrow examination revealed pure red cell aplasia (PRCA). He was diagnosed as having myasthenia gravis (MG) and invasive thymoma, and achieved complete remission by radiation and chemotherapy six years ago. Despite increased doses of oral prednisolone from 7.5 mg/day to 60 mg/day, a diagnosis of T-cell acute lymphoblastic leukemia (T-ALL) was made one month later based on findings of 37.2% abnormal lymphoblasts and positive surface markers for CD2, CD3 and CD7 T-cells. Cases of PRCA associated with MG and thymoma have been reported in the literature, however such a case followed by T-ALL is very rare.

[Basilar artery migraine with transient MRI and EEG abnormalities]

We report a case of basilar artery migraine with transient MRI and EEG abnormalities. A 25-year-old male medical student developed a right occipital throbbing headache one hour after the abrupt onset of vertigo, nausea, left-sided homonymous hemianopsia and nystagmus. All of his complaints subsided the following day. He had suffered from attacks of headache accompanied by the same type of aural symptoms almost every ten days. He was therefore diagnosed as having basilar artery migraine. CT scans during the period of recurrent migraine demonstrated no abnormalities, while T2-weighted MR images revealed a high signal intensity region in the right occipital cortex and adjacent white matter perfused by rami temporales of the right posterior cerebral artery. Cerebral hypoperfusion was detected by a SPECT scanner in the right posterior region, where EEG recorded during the migraine attack demonstrated paroxysmal-localized sharp waves. MRI and EEG performed two months after the last attack showed no obvious abnormalities along with clinical disappearance of the migraine attacks. We found few reports of transient MRI changes associated with migraine. This case suggests that transient changes in MR images reflect vasogenic edema caused by migraine.

Determination of felodipine and its metabolites in plasma using capillary gas chromatography with electron-capture detection and their identification by gas chromatography-mass spectrometry

A novel method for the determination of felodipine and its metabolites in plasma by capillary gas chromatography (GC) with electron capture detection was developed. Felodipine and its oxidized metabolite were assayed by capillary GC after solid-phase extraction with the aid of a cool on-column injection technique. Acid metabolites, methyl monoacid and ethyl monoacid and diacid, were extracted with diethyl ether and propylated with 1-n-propyl-3-p-tolyltriazene before being submitted to capillary GC. These methods were very sensitive and useful for the pharmacokinetic study of felodipine. Felodipine and its metabolites were identified by GC-mass spectrometry. The mass spectral patterns of the peaks of extracts from human plasma samples after oral administration of felodipine were in good agreement with those of reference compounds.

Formation of crystals of the insecticidal proteins of Bacillus thuringiensis subsp. aizawai IPL7 in Escherichia coli

Escherichia coli JM103 cells harboring expression plasmid pTB1 or pKC6 synthesized the 130- and 135-kilodalton insecticidal proteins, respectively, of Bacillus thuringiensis subsp. aizawai IPL7, and both products accumulated as cytoplasmic inclusion bodies. Amorphous inclusions which contained contaminating proteins, together with the corresponding insecticidal proteins, were formed in cultures at 37 degrees C, but bipyramidal crystals practically free of contaminants were observed at 30 degrees C. Although 9.8% of the amino acids were substituted between these two proteins, both protein crystals had the same shape as those of the parental B. thuringiensis strain, which produced both proteins.

Improved direct injection method and extractive methylation method for determination of valproic acid in serum by gas chromatography

Two simple methods for the determination of valproic acid in serum by gas chromatography are described. One is a direct injection method. To the serum sample are added an acetonitrile solution including an internal standard and hydrochloric acid. The sample is deproteinized and after centrifugation valproic acid in the supernatant is measured in the free form by direct injection into the gas chromatograph. The other is an extractive methylation method. To the serum sample are added an internal standard solution and a counter-ion solution, and the mixture is extracted into methylene chloride containing methyl iodide. Valproic acid is extracted into methylene chloride and simultaneously the methylation reaction proceeds. After centrifugation, an aliquot of the lower layer without evaporation is injected into the gas chromatograph. Both methods have been applied successfully to monitoring routine serum levels of valproic acid.