IgA vasculitis

Comparison of clinical and laboratory data of adult patients with cutaneous IgA vasculitis and non-IgA vasculitis

BACKGROUND

Immune complex vasculitides may be subdivided into adult IgA small vessel vasculitis (aIgA-SVV; i.e. adult Henoch-Schönlein purpura) and non-IgA-SVV (hypersensitivity vasculitis, etc.).

OBJECTIVES

To evaluate the clinical and laboratory parameters of inpatients fulfilling the diagnostic criteria for aIgA-SVV and non-IgA-SVV.

METHODS

Twenty-nine adults aged ≥ 20 years with aIgA-SVV [according to the European League Against Rheumatism/Paediatric Rheumatology International Trials Organisation/Paediatric Rheumatology European Society (EULAR/PRINTO/PRES) criteria] and 53 adults with non-IgA-SVV (according to the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides) were compared with respect to a variety of clinical and laboratory parameters by uni- and multivariable analyses.

RESULTS

Compared with patients with aIgA-SVV, the platelet-to-lymphocyte ratio was significantly higher in patients with non-IgA-SVV. Serum C3 levels and mean corpuscular haemoglobin concentration in patients with non-IgA-SVV were significantly lower compared with patients with aIgA-SVV. Proteinuria and haematuria were significantly more common in patients with aIgA SVV, and were significantly correlated with systemic immune-inflammation biomarkers only in patients with aIgA-SVV. In patients with aIgA-SVV, higher lactate dehydrogenase and C-reactive protein were strong independent predictors for the presence of proteinuria and proteinuria. In patients with non-IgA-SVV, female sex was a protective factor for proteinuria, while skin lesions on the upper extremities proved to be a significant independent predictor of haematuria.

CONCLUSIONS

We detected several clinical and laboratory differences between patients with aIgA-SVV and non-IgA-SVV. Distinct predictors for renal involvement were not observed in either group, indicating that aIgA-SVV and non-IgA-SVV are similar conditions but do not appear to represent the same entity.

Lung Involvement in Pulmonary Vasculitis: A Radiological Review

Pulmonary vasculitis identifies a heterogeneous group of diseases characterized by inflammation, damage and necrosis of the wall of pulmonary vessels. The most common approach to classify vasculitis is according to etiology, therefore dividing them into primary and secondary, with a further sub-classification of primary vasculitis based on the size of the affected vessels (large, medium, and small). Pulmonary involvement is frequently observed in patients with systemic vasculitis and radiological presentation is not pathognomonic, but may vary between diseases. The main findings using high-resolution computed tomography (HRCT) include small vessel wall thickening, nodular lesions, cavitary lesions, reticular opacities, ground-glass opacities (GGO), consolidations, interlobular septal thickening, tracheobronchial stenosis, and aneurysmal dilatation of pulmonary arteries, with or without pleural effusion. Radiological diagnosis alone is difficult since signs and symptoms of lung vessel involvement are often non-specific and might overlap with other conditions such as infections, connective tissue diseases and neoplasms. Therefore, the aim of this review is to describe the most common radiological features of lung involvement in pulmonary vasculitis so that, alongside detailed clinical history and laboratory tests, a prompt diagnosis can be performed.

Mendelian randomization reveals association of gut microbiota with Henoch-Schönlein purpura and immune thrombocytopenia

Gut microbiota have been linked to immune thrombocytopenia (ITP) and Henoch-Schönlein purpura (HSP) in recent studies, but a cause-and-effect relationship is unclear. We used Mendelian randomization (MR) to assess causal relationships between gut microbiota and HSP/ITP using summary statistics from the GWAS dataset of the international MiBioGen and FinnGen consortium. The IVW method was used as the main evaluation indicator. MR analysis of 196 intestinal flora and HSP/ITP/sTP phenotypes showed that 12 flora were potentially causally associated with ITP, 6 with HSP, and 9 with sTP. The genes predicted that genus Coprococcus3 (p = 0.0264, OR = 2.05, 95% CI 1.09-3.88)and genus Gordonibacter (p = 0.0073, OR = 1.38; 95% CI 1.09-1.75) were linked to a higher likelihood of developing ITP. Additionally, family Actinomycetaceae (p = 0.02, OR = 0.51, 95% CI 0.28-0.90) and order Actinomycetales (p = 0.0199, OR = 0.50, 95% CI 0.28-0.90) linked to reduced HSP risk. Genus Ruminococcaceae UCG013 (p = 0.0426, OR = 0.44, 95% CI 0.20-0.97) negatively correlated with sTP risk. Our MR analyses offer evidence of a possible cause-and-effect connection between certain gut microbiota species and the likelihood of HSP/ITP.

The Clinical Effect and Safety of Dihuang Decoction in Henoch-Schönlein Purpura Compared With Different Traditional Programs: A Network Meta-Analysis

This systematic review aims to evaluate the therapeutic efficacy of Dihuang decoction (DD), anti-inflammatory drugs (AIDs), blood circulation improvement drugs (BCIDs), and conventional therapy (CT) in the management of Henoch-Schönlein purpura (HSP) and to establish their comparative effectiveness rankings. Using the Population, Intervention, Comparison, Outcome, Study (PICOS) design framework, we developed a detailed search strategy. The literature search included databases such as PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang Data, Weipu Journal Data, and the Chinese Biomedical Database, covering studies published up to June 2024. We included randomized controlled trials that featured the DD as the experimental intervention, with three remaining treatments as comparators. Our analysis encompassed 63 studies with 5,435 participants, divided into 2,817 in the experimental group and 2,618 in the control group. The network meta-analysis suggested that the DD potentially surpasses AIDs, BCIDs, and CT in the management of HSP. This conclusion is supported by its superior SUCRA (Surface Under the Cumulative Ranking) scores across various measures, including the overall effective rate of medication, time to relief or disappearance of the rash, incidence of adverse reactions, time to relief or disappearance of abdominal pain, time to relief or disappearance of arthritic swelling or pain, IgA levels, and the relapse rate within six months (SUCRA scores: 100.0%, 88.3%, 79.8%, 94.4%, 99.9%, 88.3%, and 95.4%, respectively). In terms of overall effectiveness rate, the SUCRA efficacy rankings are as follows: DD > AIDs > AIDs+BCID > BCID > CT. Regarding rash relief and regression time, the SUCRA efficacy rankings are as follows: DD > CT > AIDs+BCID > AIDs. For the incidence rate of adverse reactions, the SUCRA efficacy rankings are as follows: DD > CT > AIDs > BCID > AIDs+BCID. For the relief and disappearance of abdominal pain, the SUCRA efficacy rankings are as follows: DD > CT > AIDs+BCID > AIDs. In terms of relief and disappearance of joint swelling and pain, the SUCRA efficacy rankings are as follows: DD > AIDs+BCID > AIDs. Regarding IgA changes, the SUCRA efficacy rankings are as follows: DD > CT > BCID > AIDs+BCID > AIDs. For the six-month recurrence rate, the SUCRA efficacy rankings are as follows: DD > AIDs > AIDs+BCID > CT. The DD appears to be a more effective alternative for treating HSP compared to AIDs, BCIDs, and CT. We hope that this study will provide better assistance to clinical practice.

Predicting renal damage in children with IgA vasculitis by machine learning

BACKGROUND

Children with IgA Vasculitis (IgAV) may develop renal complications, which can impact their long-term prognosis. This study aimed to build a machine learning model to predict renal damage in children with IgAV and analyze risk factors for IgA Vasculitis with Nephritis (IgAVN).

METHODS

50 clinical indicators were collected from 217 inpatients at our hospital. Six machine learning algorithms-Logistic Regression, Linear Discriminant Analysis, K-Nearest Neighbor, Support Vector Machine, Decision Trees, and Random Forest-were utilized to select the model with the highest predictive performance. A simplified model was developed through feature importance ranking and validated by an additional cohort with 46 patients.

RESULTS

The random forest model had the highest accuracy, precision, recall, F1 score, and area under the curve, with values of 0.91, 0.98, 0.70, 0.79 and 0.94, respectively. The top 11 features according to the importance ranking were anti-streptolysin O, corticosteroids therapy, antihistamine therapy, absolute eosinophil count, immunoglobulin E, anticoagulant therapy, C-reactive protein, prothrombin time, age at onset, D-dimer, recurrence of rash ≥ 3 times. A simplified model using these features demonstrated optimal performance with an accuracy of 84.2%, a sensitivity of 89.4%, and a specificity of 82.5% in external validation. Finally, we provided a web tool based on the simplified model, whose code was published on https://github.com/mulanruo/IgAVN_Prediction .

CONCLUSION

The model based on the random forest algorithm demonstrates good performance in predicting renal damage in children with IgAV, providing a basis for early clinical diagnosis and decision-making.

Associations of MEFV gene variants, IL-33, and sST2 with the risk of Henoch-Schönlein purpura in children

Objective

Henoch-Schönlein purpura (HSP) is the most common systemic vasculitis in children. HSP is a multifactorial inflammatory disease, but its pathogenesis is still unclear. The pathogenicity of familial Mediterranean fever gene (MEFV) variants in HSP remains controversial. The objective of this study was to evaluate relationships between MEFV variants and susceptibility to HSP and their associations with clinical outcomes. We also investigated levels of IL-33 and soluble suppression of tumorigenicity 2 (sST2) in children with HSP and their clinical significance.

Methods

We selected 100 children with HSP as the case group. The control group consisted of 50 children who visited the hospital for physical health examinations. All subjects were screened for MEFV gene exon mutations, and levels of IL-33 and sST2 were measured.

Results

The frequency of MEFV variants was significantly greater in HSP patients than in healthy controls. The variant with the highest frequency was E148Q. The frequency of the C allele of the MEFV variant E148Q was 32 % in HSP patients and 18 % in controls (P-adjust = 0.04). Patients with the MEFV E148Q variant had more frequent joint involvement and recurrent purpura and higher levels of IL-33 and C-reactive protein (CRP). Levels of IL-33 and sST2 in children with HSP were significantly higher than those in the control group, and the sST2/IL-33 ratio in children with HSP was unbalanced (P-adjust <0.05). Logistic regression analysis revealed the presence of E148Q and an unbalanced sST2/IL-33 ratio to be independent risk factors for HSP.

Conclusion

The results of this study suggest that the MEFV variant E148Q is associated with HSP susceptibility in Chinese children and that carriers of the variant may have more severe clinical manifestations and greater inflammatory responses. E148Q and the sST2/IL-33 ratio may play important roles in the pathogenesis of HSP.

[Immunoglobulin A vasculitis]

The immune-mediated small vessel vasculitis is known as Schoenlein-Henoch purpura predominantly from pediatrics and in these cases occurs more frequently after infections of the upper airways. In adults, immunoglobulin A (IgA) vasculitis often proceeds more severely und recurrently with the classical tetrad of skin manifestations in the sense of leukocytoclastic vasculitis, joint affection, gastrointestinal involvement and IgA nephritis, in contrast to the mostly mild and self-limiting course in children. The background of this systemic vasculitis with formation of IgA immune complexes is considered to be an altered glycosylation of IgA, as this causes the exposure of binding sites for autoantibodies so that an immune complex reaction can be elicited. This ultimately leads to perivascular deposition of IgA and a further activation of neutrophils. Groundbreaking in the diagnostics is the histological detection of leukocytoclastic vasculitis and in cases of renal manifestations a kidney biopsy with characteristic deposits of immune complexes, which cannot be clearly differentiated from IgA nephropathy. The treatment is aimed at the respective manifestation and is mostly based on consensus recommendations due to the lack of randomized studies. In addition to immunosuppressive medication, in the presence of a chronic kidney disease general nephroprotection is becoming increasingly more important also by inhibition of sodium-glucose transporter 2 (SGLT2). The type and extent of kidney involvement and also rare cardiac manifestations are the main determinants of the prognosis. Continuous medical accompaniment of those affected is necessary due to the possible progression of the disease and the risk of recurrence.

Association between TRAF1/C5 Gene Polymorphisms and IgA Vasculitis in Chinese Children

OBJECTIVE

To investigate the association between loci rs3761847 and rs10818488 of tumor necrosis factor receptor-associated factor 1/complement C5 (TRAF1/C5) gene and the susceptibility to IgAV.

METHODS

100 blood samples of children with IgAV and 100 blood samples of healthy children were collected from the Third Xiangya Hospital of Central South University from June 2017 to June 2019. The target gene fragment was amplified by polymerase chain reaction (PCR), and the single nucleic acid gene polymorphism of the gene loci was detected by PCR sequencing based typing technique. The association between gene polymorphism of each locus and susceptibility to IgAV was analyzed.

RESULTS

There were significant differences in both genotype (P < .05) and allele frequencies （P < .05) of rs3761847 of TRAF1/C5 gene between the IgAV group and the control group.Besides, the risks of developing IgAV in children with the TT genotype was 0.495 times and in children with the C allele was 1.627 times of that in children with other genotypes and alleles, respectively (P < .05). For IgAV patients, renal involvement risk in children with CC genotype was 5.859 times of that in children with other genotypes (P < .05). There were no significant differences in genotype (P > .05) and allele frequencies (P > .05) of rs10818488 of TRAF1/C5 gene between the IgAV group and the control group. IgAV patients with TT genotype had a 3.2 times higher risk of renal involvement than those with other genotypes (P < .05).

CONCLUSIONS

There is an association between locus rs3761847 of TRAF1/C5 gene single nucleotide polymorphisms and susceptibility to IgAV. The T allele at locus rs3761847 of TRAF1/C5 gene may be a protective factor for IgAV. The C allele at locus rs3761847 and the T allele at locus rs10818488 of TRAF1/C5 gene may be associated with kidney injury in IgAV.

Characteristics of renal pathology and coagulation function in IgA nephropathy and IgA vasculitis associated nephritis

BACKGROUND

The objective of this study is to investigate the clinical and pathological differences between patients with IgA nephropathy (IgAN) and IgA vasculitis associated nephritis (IgAVN).

METHODS

A total of 253 patients with IgAN and 71 patients with IgAVN were retrospectively included in the study, and clinical and laboratory data were collected and analysed.

RESULTS

Compared with IgAVN group, months from onset to kidney biopsy were significantly prolonged in IgAN patients because of the lack of obvious symptoms such as rash, abdominal symptoms, and joint pain (13.5 ± 26.6 vs. 10.2 ± 31.6 months, P = 0.007), and the levels of serum creatinine (92.3 ± 94.7 vs. 68.9 ± 69.2 µmol/L, P = 0.015) was higher and eGFR (99.1 ± 35.2 vs. 123.4 ± 41.8 mL/min/1.73m2, P < 0.001) was lower in IgAN group. The pathological results revealed that patients with IgAN have a greater degree of chronic kidney injury compared to patients with IgAVN. In addition, the levels of plasma D-Dimers (1415.92 ± 1774.69 vs. 496.78 ± 711.91 ng/mL, P < 0.001) and fibrinogen degradation products (FDP) (3.92 ± 4.73 vs. 1.63 ± 2.46 µg/mL, P = 0.001) were significantly higher in IgAVN patients than in IgAN patients. The deposition of fibrinogen in the renal tissues was more severe and the cumulative partial remission rate was higher in patients with IgAVN as compared to those with IgAN (P = 0.001).

CONCLUSIONS

In comparison, IgAN patients had poorer renal function, whereas IgAVN patients had more severe coagulation abnormalities. These findings provide a basis for the differentiation of the two diseases at an early stage.

Mendelian randomization analysis reveals causality of inflammatory bowel disease on risks of Henoch-Schönlein purpura and immune thrombocytopenia

BACKGROUND

Emerging clinical evidence has been discovered associating Inflammatory bowel disease (IBD) with Henoch-Schönlein purpura (HSP) and immune thrombocytopenia (ITP). However, it is unclear whether a cause-effect relationship exists between them. We aimed to examine the casual effect of IBD on the risk of HSP and ITP.

METHODS

Based on summary statistics from International IBD Genetics (IIBDG) Consortium and FinnGen study, a two-sample Mendelian randomization study was carried out to determine whether IBD including ulcerative colitis (UC) and Crohn's disease (CD) is causally related to HSP, ITP or secondary thrombocytopenia. To support the results, a variety of sensitivity analyses were performed.

RESULTS

Significant causal relationships between IBD and HSP (odds ratios = 1.20, 95% confidence interval: 1.07-1.36, adjusted P = 0.006) and ITP (odds ratios =1.22, 95% confidence interval: 1.08-1.38, adjusted P = 0.006) were found. Both genetically predicted UC and CD were positively related with ITP, while CD alone may be responsible for the higher risk of HSP. Besides, no significant association was observed between IBD and secondary thrombocytopenia.

CONCLUSIONS

The results of this Mendelian randomization study supported the causal association of IBD with HSP and ITP. Taken together, our findings may present implications for management of IBD.

Rituximab as possible therapy in TNF inhibitor-induced IgA vasculitis with severe renal involvement

BACKGROUND

We observe the increasing use of tumor necrosis factor (TNF) inhibitors in patients affected by chronic inflammatory diseases. These drugs provide good control of symptoms, contributing to significant improvement in the quality of life in individuals with high disease burden. On the other hand, along with their wider use and longer follow-up periods the number of reports regarding their adverse effects is also increasing. The reported complications include drug-induced vasculitis with possible kidney involvement. In the literature we can distinguish more frequently described ANCA-associated vasculitis and more rarely occurring immunoglobulin A vasculitis. Although uncommon, such complications may present with potentially life-threatening vital organ dysfunction; therefore, adequate monitoring and effective therapy are necessary.

CASE PRESENTATION

We report two cases of TNF inhibitor-induced vasculitis with severe acute worsening of renal function and significant proteinuria. The first patient was receiving golimumab therapy for ankylosing spondylitis and the second patient was treated with adalimumab for psoriasis and psoriatic arthritis. In the second case dialysis treatment was necessary and the patient presented recurrence of vasculitis after rechallenge with adalimumab. Both patients underwent renal biopsy which showed findings compatible with drug-induced IgA vasculitis and both were treated successfully with corticosteroids and rituximab.

CONCLUSIONS

To the best of our knowledge this is the first report of rituximab use in drug-induced IgA vasculitis with renal involvement. Combination of corticosteroids and rituximab can be an effective therapy in case of vasculitis with kidney failure and a preferable option for selected patients with drug-induced IgA vasculitis compared to cyclophosphamide. More studies are necessary to establish suitable short- and long-term treatment. Given the rarity of this disorder, case reports and case series can provide practical guidance until additional studies become available.

IgA nephropathy

IgA nephropathy (IgAN), the most prevalent primary glomerulonephritis worldwide, carries a considerable lifetime risk of kidney failure. Clinical manifestations of IgAN vary from asymptomatic with microscopic or intermittent macroscopic haematuria and stable kidney function to rapidly progressive glomerulonephritis. IgAN has been proposed to develop through a 'four-hit' process, commencing with overproduction and increased systemic presence of poorly O-glycosylated galactose-deficient IgA1 (Gd-IgA1), followed by recognition of Gd-IgA1 by antiglycan autoantibodies, aggregation of Gd-IgA1 and formation of polymeric IgA1 immune complexes and, lastly, deposition of these immune complexes in the glomerular mesangium, leading to kidney inflammation and scarring. IgAN can only be diagnosed by kidney biopsy. Extensive, optimized supportive care is the mainstay of therapy for patients with IgAN. For those at high risk of disease progression, the 2021 KDIGO Clinical Practice Guideline suggests considering a 6-month course of systemic corticosteroid therapy; however, the efficacy of systemic steroid treatment is under debate and serious adverse effects are common. Advances in understanding the pathophysiology of IgAN have led to clinical trials of novel targeted therapies with acceptable safety profiles, including SGLT2 inhibitors, endothelin receptor blockers, targeted-release budesonide, B cell proliferation and differentiation inhibitors, as well as blockade of complement components.

[Association between vaccination and the risk of immunoglobulin A vasculitis in children]

OBJECTIVES

To study the effect of vaccination on the short-term risk of immunoglobulin A vasculitis (IgAV) in children.

METHODS

A retrospective analysis was conducted on the general data and the vaccination history within one year prior to onset in children with IgAV hospitalized in the Children's Hospital Affiliated to Zhengzhou University from November 2021 to January 2023. Vaccine exposure rates in the risk period (3 months prior to IgAV onset) and the control period were compared by autocontrol-case crossover analysis, and the odds ratio and 95% confidence interval (95%CI) were calculated. A sensitivity analysis for the one-month and two-month risk periods was conducted.

RESULTS

A total of 193 children with IgAV were included, with a median age of 7.0 years. Among the 193 children, 36 (18.7%) received at least one dose of the vaccine within 1 year prior to IgAV onset, and 14 (7.3%) received at least one dose of the vaccine during the 3-month risk period. Compared to the unvaccinated IgAV group, the vaccinated IgAV group had a significantly younger age of onset (P<0.05). There were no significant differences in the proportions of children with gastrointestinal involvement, renal involvement, and joint involvement between the two groups (P>0.05). The odds ratio for developing IgAV after receiving any type of vaccine within 3 months prior to IgAV onset was 2.08 (95%CI: 0.82-5.27, P>0.05). Further sensitivity analysis for the 1-month and 2-month risk periods demonstrated that the odds ratios for developing IgAV after receiving any type of vaccine were 2.74 (95%CI: 0.72-10.48, P>0.05) and 2.72 (95%CI: 0.95-7.77, P>0.05), respectively.

CONCLUSIONS

Vaccination dose not increase the risk of IgAV, nor does it exacerbate clinical symptoms in children with IgAV.

New insights into epidemiological data and impact of the COVID-19 pandemic on IgA vasculitis in children and adults: a French nationwide cohort

IgA vasculitis (IgAV) is a small size vasculitis for which epidemiologic data are strikingly lacking, especially about the adult form. Additionally, the COVID-19 pandemic seems to have profoundly modified the incidence of this disease. Here, we aimed to establish some relevant epidemiological data in both pediatric and adult IgAV. We performed an observational study using a national database called "BNDMR" on IgAV, which gathers patients managed in the French network of experts on rare diseases. We primarily performed descriptive statistics over the 2010-2022 period. Then, we compared the North-South geographical areas, the seasonality, and the impact of COVID-19 with that of other patients reported in the same centers. We collected data from 1988 IgAV patients. The sex ratio was 1.57 for adults and 1.05 for children. The annual incidence in 2021 was 0.06 for 100,000 adults and 0.50 for 100,000 children. Compared with other diseases reported into the BNDMR, IgAV was more common in the South than in the North of France (OR 4.88 [4.17-5.74] in adults and OR 1.51 [1.35-1.68] in children). IgAV was also observed more frequently in winter and autumn. Strikingly, we observed a decrease in incidence during the COVID-19 pandemic period in children (OR 0.62 [0.47-0.81]). Our study provides both new insights and confirmations of IgAV epidemiological data: winter and autumn seasonality, more pronounced male predominance in adults, decreasing incidence of pediatric IgAV during the COVID-19 pandemic and increasing incidence in the South of France.

IgA Vasculitis Followed by IgA Nephropathy Without an Identifiable Trigger: The Same Disease or a Spectrum of Related Conditions?

IgA vasculitis and IgA nephropathy are characterized by IgA deposition in blood vessels and glomerular mesangium, respectively. The former is far more common in the pediatric population, while the latter presents more often in adulthood. A consensus regarding whether these two conditions are manifestations of the same disease that occurs on a spectrum has not yet been reached, and, to our knowledge, no clinical trials to address this question have been conducted. Here, we describe a 27-year-old patient who presented to the emergency department multiple times before being diagnosed with IgA vasculitis with no identifiable trigger and soon after developed IgA nephropathy. This case highlights the importance of ruling out these conditions, especially IgA vasculitis, in adults presenting with a petechial rash, but also the need for studies that investigate whether and how these conditions are related so that patients can be appropriately diagnosed and treated as efficiently as possible.

Tubulointerstitial B-cell infiltration and tertiary lymphoid tissue in adult-onset immunoglobulin A vasculitis with nephritis

PURPOSE

This study aimed to examine tubulointerstitial B-cell infiltration in patients with adult-onset immunoglobulin A vasculitis (IgAV) and nephritis (IgAV-N), and to evaluate whether B-cell infiltration correlated with clinicopathological variables at kidney biopsy and with short-term renal outcomes.

METHODS

Twenty patients with adult-onset IgAV-N and 10 control patients with thin basement membrane nephropathy (TBMN) were retrospectively examined. The lymphatic organization was graded based on B-cell infiltration and was classified into 4 groups: 0-T cells without B cells, 1-scattered B and T cells, 2-clustered B and T cells, and 3-nodular compartmentally arranged B- and T-cell aggregates, equivalent to tertiary lymphoid tissue (TLT).

RESULTS

The B-cell infiltration grade was significantly higher in patients with IgAV-N than in patients with TBMN, and no age differences were observed. The B-cell infiltration grade in patients with IgAV-N was significantly correlated with age, serum IgA level, renal dysfunction, and tubulointerstitial injury parameters, but was not correlated with duration after purpura or glomerular injury parameters. Most patients with IgAV-N were treated with corticosteroids. The proteinuria level was significantly decreased, but renal function was not improved in 12 patients after the 24-month follow-up compared with the values at baseline. The B-cell infiltration grade was significantly correlated with renal dysfunction after 24 months of follow-up.

CONCLUSIONS

The B-cell infiltration grade in patients with IgAV-N was associated with renal dysfunction and tubulointerstitial injuries but not with glomerular injury parameters. B-cell infiltration and TLT might have a pathologically significant role in irreversible renal dysfunction in patients with early phase adult-onset IgAV-N.

Towards better indications for kidney biopsy in adult IgA vasculitis: a clinical-laboratory and pathology correlation study

BACKGROUND

Indications for kidney biopsy in adult IgA vasculitis (IgAV) remain debated and there are very few studies on this subject. The aim of this study was to establish a correlation between renal histological and clinical-laboratory data.

METHODS

A retrospective multicenter study was conducted using three databases from French hospitals, gathered between 1977 and 2020. The study included 294 adult patients with IgAV who had undergone kidney biopsy assessed according to the prognostic "Pillebout classification". Different statistical models were used to test the correlations between histological and clinical-laboratory data: Cochran Armitage, ANOVA, Kruskal-Wallis and logistic regression.

RESULTS

The patients were primarily men (64%), with a mean age of 52 years. The main organs and tissues involved were: dermatological 100%, digestive 48% and rheumatological 61%. All had features of kidney involvement. The median serum creatinine was 96 µmol/L serum albumin 35 g/L, and C-reactive protein 28 mg/L. Of the patients, 86% (n = 254) had hematuria and median proteinuria was 1.8 g/day. The only statistically significant correlation between the pathological stages and the clinical-laboratory data was the presence of hematuria (p = 0.03, 66% class I to 92% class IV). In multivariate analysis, only albuminemia was associated with extracapillary proliferation (p = 0.02; OR 0.94) and only age was associated with stages 3-4 (p = 0.03; OR 1.02).

CONCLUSION

Our study suggests that there is no strict baseline correlation between renal pathology and clinical-laboratory data. Given the current knowledge, it seems relevant to recommend a kidney biopsy in the presence of significant and persistent proteinuria or unexplained kidney function decline.

Patient-reported outcomes in vasculitis

Systemic vasculitis encompasses a group of multisystem disorders; both the diseases and the treatment strategies can have a significant impact on a patient's health-related quality of life (HRQoL). Using patient-reported outcome measures (PROMs) and patient-reported experience measures (PREMs) to evaluate the patient's view of their condition, treatments, and healthcare journey is essential to the patient-centered care approach. In this paper, we discuss the use of generic, disease-specific, and treatment-specific PROMs and PREMs in systemic vasculitis and future research goals.

Adult-Onset Immunoglobulin A Vasculitis Following Hemodialysis Treatment: An Unusual Presentation

Immunoglobulin A (IgA) vasculitis, formerly known as Henoch-Schönlein purpura (HSP), is a small vessel vasculitis due to perivascular deposition of dominant IgA immune complexes. It classically presents with symptoms such as palpable purpura, abdominal pain, kidney dysfunction, and joint pain. It most commonly affects children less than 10 years old. We present the case of a 53-year-old male who developed purpuric rashes a few hours after receiving hemodialysis. Initially, the lesions were localized to his legs and buttocks. They continued to spread over his back, abdomen, and arms. He experienced joint pain in both of his wrists, as well as abdominal tenderness. Labs revealed elevated IgA levels: 422 mg/dL (normal: 61 - 356 mg/dL). C3, C4, and antinuclear antibody (ANA) levels were within normal limits. Oral prednisone and topical diphenhydramine resulted in significant improvement in his symptoms. To our knowledge, there are only five reports documenting the occurrence of HSP in adults undergoing hemodialysis. Although HSP is a rare finding in adults, recognition of the disease is important as it can cause significant morbidity and mortality if left untreated.

IgA Vasculitis Following COVID-19 Vaccination: A French Multicenter Case Series Including 12 Patients

OBJECTIVE

The worldwide coronavirus disease 2019 (COVID-19) vaccination campaign triggered several autoimmune diseases. We hereby aimed to describe IgA vasculitis (IgAV) following COVID-19 vaccination.

METHODS

We conducted a national, multicenter, retrospective study in France of new-onset adult IgAV diagnosis following COVID-19 vaccination.

RESULTS

In total, 12 patients with new-onset IgAV were included. Of these, 5 (41.7%) were women, and the median age was 52.5 (IQR 30.75-60.5) years. Of the 12 patients, 10 had received an mRNA vaccine and 2 had received a viral vector vaccine. The median time from vaccination to onset of symptoms was 11.5 (IQR 4.25-21.25) days. Vasculitis occurred after the first vaccine dose in most patients (n = 8). All patients had skin involvement, with skin necrosis in 4 patients. In total, 7 patients had joint involvement and 2 had arthritis. A total of 4 patients had nonsevere gastrointestinal involvement and 2 had nonsevere renal involvement. The median C-reactive protein level was 26 (IQR 10-66.75) mg/L, the median creatininemia level was 72 (IQR 65-81) μmol/L, and 1 patient had an estimated glomerular filtration rate of less than 60 mL/min at management. All patients received treatment, including 9 patients (75%) who received glucocorticoids. In total, 5 patients received a vaccine dose after developing IgAV, 1 of whom experienced a minor cutaneous relapse.

CONCLUSION

The baseline presentation of IgAV following COVID-19 vaccination was mild to moderate, and outcomes were favorable. Thus, a complete COVID-19 vaccination regimen should be completed in this population. Of note, a fortuitous link cannot be ruled out, requiring a worldwide pharmacovigilance search to confirm these findings.

Current understanding of IgA antibodies in the pathogenesis of IgA nephropathy

Immunoglobulin A (IgA) is the most abundant isotype of antibodies, provides a first line of defense at mucosal surfaces against pathogens, and thereby contributes to mucosal homeostasis. IgA is generally considered as a non-inflammatory antibody because of its main function, neutralizing pathogenic virus or bacteria. Meanwhile, IgA can induce IgA-mediated diseases, such as IgA nephropathy (IgAN) and IgA vasculitis. IgAN is characterized by the deposition of IgA and complement C3, often with IgG and/or IgM, in the glomerular mesangial region, followed by mesangial cell proliferation and excessive synthesis of extracellular matrix in glomeruli. Almost half a century has passed since the first report of patients with IgAN; it remains debatable about the mechanism how IgA antibodies selectively bind to mesangial region-a hallmark of IgAN-and cause glomerular injuries in IgAN. Previous lectin- and mass-spectrometry-based analysis have revealed that IgAN patients showed elevated serum level of undergalactosylated IgA1 in O-linked glycans of its hinge region, called galactose-deficient IgA1 (Gd-IgA1). Thereafter, numerous studies have confirmed that the glomerular IgA from IgAN patients are enriched with Gd-IgA1; thus, the first hit of the current pathogenesis of IgAN has been considered to increase circulating levels of Gd-IgA1. Recent studies, however, demonstrated that this aberrant glycosylation alone is not sufficient to disease onset and progression, suggesting that several additional factors are required for the selective deposition of IgA in the mesangial region and induce nephritis. Herein, we discuss the current understanding of the characteristics of pathogenic IgA and its mechanism of inducing inflammation in IgAN.

Pathophysiology and clinical manifestations of immune complex vasculitides

Immune complex (IC) vasculitides present inflammations of vessel walls associated with perivascular deposition of immunoglobulins (Igs), mostly ICs. They encompass systemic and skin-limited variants of IgA vasculitis (IgAV), cryoglobulinemic vasculitis (CV), rheumatoid, lupus, and hypocomplementemic vasculitides, serum sickness cutaneous IgM/IgG (non-IgA) vasculitis, and recurrent macular (hypergammaglobulinemic or exertion-induced) vasculitis. Serum sickness and CV fulfill the criteria of a type III hypersensitivity immune reaction as large lattices of the IC precipitate at vessel walls and activate polymorphonuclear neutrophils (PMNs). Immunoglobulin-A vasculitis differs with regard to the causes of perivascular deposition of ICs since here many IgA1 molecules are hypoglycosylated (Gd-IgA1), which appears to facilitate their perivascular deposition in skin and mesangium (via e.g. CD71). The reasons for increased generation of immunoglobulins or formation of IC and their perivascular deposition in either skin or systemic organs are different and not fully explored. A common denominator of OC vasculitides is the activation of PMNs near the vessel wall via Fcy or Fcα receptors. Acute episodes of IgAV additionally require PMNs to become preactivated by IgA1 or by IC already in circulation. This intravascular priming results in increased adherence and subsequently vessel-destructive NETosis when they encounter IgA deposited at the vessel walls. Binding of IgA1 to PMNs in blood stream is associated with increased serum levels of hypogalactosidated IgA1. The characteristic clinical picture of IgAV (and also of so-called IgG/IgM vasculitis) comprises palpable or retiform purpura with a clear predilection for lower legs, probably due to stasis-related reduction in blood velocity, while in other IC vasculitides, additional factors influence the sites of vasculitides. Our knowledge of distinct forms and different pathophysiological pathways of IC vasculitides may lead to in efficacious or targeted therapies. Antibodies to complement components or intestinal budesonide for IgAV are promising agents (the latter suppresses the pathophysiologically related IgA nephropathy by reducing the generation of mucosal IgA.

Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO) Syndrome with Henoch-Schönlein Purpura: A Case Report

Introduction

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome is a rare disease clinically characterized by a wide range of cutaneous and osteoarticular manifestations, involving multiple system impairments. Vasculitis is a rare comorbidity of SAPHO. Henoch-Schönlein purpura (HSP) is a vasculitis involving the capillaries and arterioles mediated by IgA immune complex. No case report of SAPHO syndrome with HSP was ever found.

Case

Here we reported a case of SAPHO syndrome complicated with HSP and was successfully treated by methylprednisolone and tofacitinib.

Discussion

Although the treat-to-target management of HSP and the first-line clinical medication have given some advices on the treatment. A precise treatment was still needed based on the pathogenesis of the comorbidity. The mechanism of the co-occurrence includes innate immunity and adapted immunity. Considering the active inflammatory reaction and the rapid disease progression, methylprednisolone and tofacitinib were prescribed.

Conclusion

HSP is a new comorbidity of SAPHO. The spectrum of cutaneous small-vessel vasculitis in SAPHO syndrome was enriched. A new treatment approach for SAPHO with HSP was provided.

Immunoglobulin a vasculitis with testicular/epididymal involvement in children: A retrospective study of a ten-year period

The clinical characteristics and risk factors for testicular/epididymal involvement in 73 children with immunoglobulin A vasculitis (IgAV) who were admitted to our hospital between January 2012 and November 2022 were reviewed. The demographic data, laboratory parameters, and follow-up data of the patients were compared to those of 146 males without testicular/epididymal involvement. A logistic regression analysis was performed to determine the variables associated with testicular/epididymal involvement. The prevalence of testicular/epididymal involvement among male patients with IgAV was 1.3% (73/5,556). Increased blood flow in the testes and/or epididymis on ultrasound was found in 71 patients. The remaining two patients underwent surgical exploration for loss or reduction of testicular blood flow. One patient underwent orchiectomy for intraoperative confirmation of complete right testicular infarction. Pathological findings revealed IgA immune complex deposition in the testis. Patient age (odds ratio [OR] = 0.792; 95% confidence interval [CI]: 0.682-0.919, p = 0.002), platelet count (OR = 1.011; 95% CI: 1.002-1.020, p = 0.013), and immunoglobulin M (IgM) levels (OR = 0.236; 95% CI: 0.091-0.608, p = 0.003) were strongly associated with the occurrence of testicular/epididymal involvement in IgAV. Therefore, young age, increased platelet count, and low IgM levels in patients with IgAV are potential risk factors for testicular/epididymal involvement. Doppler ultrasound can help differentiate IgAV from acute scrotum. Most patients with testicular/epididymal involvement have good prognoses, although serious complications such as testicular infarction may occur.

Identification of key genes and imbalance of immune cell infiltration in immunoglobulin A associated vasculitis nephritis by integrated bioinformatic analysis

Background

IgAV, the most common systemic vasculitis in childhood, is an immunoglobulin A-associated immune complex-mediated disease and its underlying molecular mechanisms are not fully understood. This study attempted to identify differentially expressed genes (DEGs) and find dysregulated immune cell types in IgAV to find the underlying pathogenesis for IgAVN.

Methods

GSE102114 datasets were obtained from the Gene Expression Omnibus (GEO) database to identify DEGs. Then, the protein-protein interaction (PPI) network of the DEGs was constructed using the STRING database. And key hub genes were identified by cytoHubba plug-in, performed functional enrichment analyses and followed by verification using PCR based on patient samples. Finally, the abundance of 24 immune cells were detected by Immune Cell Abundance Identifier (ImmuCellAI) to estimate the proportions and dysregulation of immune cell types within IgAVN.

Result

A total of 4200 DEGs were screened in IgAVN patients compared to Health Donor, including 2004 upregulated and 2196 downregulated genes. Of the top 10 hub genes from PPI network, STAT1, TLR4, PTEN, UBB, HSPA8, ATP5B, UBA52, and CDC42 were verified significantly upregulated in more patients. Enrichment analyses indicated that hub genes were primarily enriched in Toll-like receptor (TLR) signaling pathway, nucleotide oligomerization domain (NOD)-like receptor signaling pathway, and Th17 signaling pathways. Moreover, we found a diversity of immune cells in IgAVN, consisting mainly of T cells. Finally, this study suggests that the overdifferentiation of Th2 cells, Th17 cells and Tfh cells may be involved in the occurrence and development of IgAVN.

Conclusion

We screened out the key genes, pathways and maladjusted immune cells and associated with the pathogenesis of IgAVN. The unique characteristics of IgAV-infiltrating immune cell subsets were confirmed, providing new insights for future molecular targeted therapy and a direction for immunological research on IgAVN.

Manifestations of the gastrointestinal tract in systemic rheumatic diseases: A narrative review

Gastrointestinal disorders are important place among the visceral manifestations of systemic autoimmune and immunoinflammatory rheumatic diseases (RD). Pathology of the esophagus, stomach, small and large intestine can vary from moderate functional disorders to the development of severe chronic inflammation with metaplasia and dysplasia of the mucous membrane, the formation of multiple erosions, hemorrhages and deep ulcers. Complications of gastrointestinal pathology in RD, such as bleeding, perforations and strictures, can cause death. This review examines the main clinical manifestations, possibilities of diagnosis and treatment of gastrointestinal lesions in systemic scleroderma, idiopathic inflammatory myopathies, systemic vasculitis, Sjogren’s syndrome and disease, as well as systemic lupus erythematosus.

Novel aspects in the pathophysiology and diagnosis of glomerular diseases

Immune deposits/complexes are detected in a multitude of tissues in autoimmune disorders, but no organ has attracted as much attention as the kidney. Several kidney diseases are characterised by the presence of specific configurations of such deposits, and many of them are under a 'shared care' between rheumatologists and nephrologists. This review focuses on five different diseases commonly encountered in rheumatological and nephrological practice, namely IgA vasculitis, lupus nephritis, cryoglobulinaemia, anti-glomerular basement membrane disease and anti-neutrophil cytoplasm-antibody glomerulonephritis. They differ in disease aetiopathogenesis, but also the potential speed of kidney function decline, the responsiveness to immunosuppression/immunomodulation and the deposition of immune deposits/complexes. To date, it remains unclear if deposits are causing a specific disease or aim to abrogate inflammatory cascades responsible for tissue damage, such as neutrophil extracellular traps or the complement system. In principle, immunosuppressive therapies have not been developed to tackle immune deposits/complexes, and repeated kidney biopsy studies found persistence of deposits despite reduction of active inflammation, again highlighting the uncertainty about their involvement in tissue damage. In these studies, a progression of active lesions to chronic changes such as glomerulosclerosis was frequently reported. Novel therapeutic approaches aim to mitigate these changes more efficiently and rapidly. Several new agents, such as avacopan, an oral C5aR1 inhibitor, or imlifidase, that dissolves IgG within minutes, are more specifically reducing inflammatory cascades in the kidney and repeat tissue sampling might help to understand their impact on immune cell deposition and finally kidney function recovery and potential impact of immune complexes/deposits.

Bibliometric analysis of IgA vasculitis nephritis in children from 2000 to 2022

Background

IgA vasculitis Nephritis (IgAVN) is a kidney-damaging disease that occurs during the course of IgA vasculitis (IgAV) and is the most serious complication of IgAV. However, there is a lack of reports of bibliometric analysis of IgAVN in children. The purpose of this study is to conduct a bibliometric analysis of IgAVN in children from 2000 to 2022, to explore the current status and cutting-edge trends in the field of IgAVN in children, and to establish new directions for subsequent research.

Methods

Screening the literature in the field of IgAVN in children in the Web of Science Core Collection (WoSCC) from 2000 to 2022. Visual analysis of their annual publications, countries, institutions, authors, journals, keywords, and references were using CiteSpace5.8.R3 and VOSviewer1.6.18.

Results

A total of 623 publications were included in the study, since the beginning of 2014, there has been an overall increasing trend in the number of articles issued. The most prolific country and institution were China and Zhejiang University. The most frequently cited author was Coppo R, with 331 citations, who has made great contributions to IgAVN. Mao Jianhua, Lee JS and Wyatt Robert J were the most prolific authors, all with 9 articles. Pediatric Nephrology was the most published and cited journal. The highest burst strength keyword is IgA vasculitis, and the highest burst strength reference is Davin JC, 2014.

Conclusion

The research hotspots and trends predicted by the analysis of this study provide a reference for in-depth research in this field with a view to promoting the development of IgAVN research in children.

Dermatopathological Correlation of Clinically Challenging Cutaneous Lesions: a Single Center Experience of 2184 Cases

INTRODUCTION

Although a trained eye can easily identify typical skin lesions, histopathological examination and clinicopathological correlation are critical in challenging cases.

OBJECTIVES

The primary objective is to organize the final diagnoses reached following clinicopathological consensus in clinically challenging cutaneous lesions, identifying the most common diagnostic scenarios encountered by dermatopathologists and discussing their diverse differentials submitted by clinicians. The secondary objective is to investigate how the case profile and clinician decision-making processes evolved during the COVID-19 pandemic.

METHODS

Skin and mucosa samples collected by the dermatology department between 2016 and 2020 were classified based on pathology reports. For frequent diagnoses, preliminary diagnoses stated by clinicians on pathology requisition forms were reviewed. The years preceding and following the first nationally reported COVID-19 case were compared to investigate the pandemic's impact on the distribution of dermatology and dermatopathology cases.

RESULTS

One thousand nine hundred and eighty-nine reports were classified into 4 major categories: inflammatory (49.8%), neoplastic (30.1%), other diseases (7.1%), and non-diagnostic (12.8%). We further classified inflammatory diseases based on major tissue reaction patterns and neoplasms based on cell origin. We analyzed the leading diagnoses in each category, discussed their differential diagnoses, and provided clinicians with clues to reduce errors in practice. Following the pandemic, the overall number of pathology reports and patient admissions dropped dramatically, with significant changes in case profiles.

CONCLUSIONS

We presented and discussed the frequently encountered confounding cases to sketch the diagnostic landscape. In the authors' experience, clinicopathological correlation can increase the rate of reaching the diagnosis by up to 75.3%.

Advances in IgA glycosylation and its correlation with diseases

Immunoglobulin A (IgA) is the most abundant immunoglobulin synthesized in the human body. It has the highest concentration in the mucosa and is second only to IgG in serum. IgA plays an important role in mucosal immunity, and is the predominant antibody used to protect the mucosal surface from pathogens invasion and to maintain the homeostasis of intestinal flora. Moreover, The binding IgA to the FcαRI (Fc alpha Receptor I) in soluble or aggregated form can mediate anti- or pro- inflammatory responses, respectively. IgA is also known as one of the most heavily glycosylated antibodies among human immunoglobulins. The glycosylation of IgA has been shown to have a significant effect on its immune function. Variation in the glycoform of IgA is often the main characteration of autoimmune diseases such as IgA nephropathy (IgAN), IgA vasculitis (IgAV), systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA). However, compared with the confirmed glycosylation function of IgG, the pathogenic mechanism of IgA glycosylation involved in related diseases is still unclear. This paper mainly summarizes the recent reports on IgA’s glycan structure, its function, its relationship with the occurrence and development of diseases, and the potential application of glycoengineered IgA in clinical antibody therapeutics, in order to provide a potential reference for future research in this field.

Cutaneous vasculitis; An algorithmic approach to diagnosis

Vasculitides, characterized by inflammation and damage of blood vessels, encompass a broad spectrum of diseases. They can occur with different pathophysiological mechanisms and have a rich clinical heterogeneity depending on the vessel diameters they affect. Vasculitides may also present with a broad spectrum of severity, ranging from a mild self-limiting to a potentially life-threatening disease. The high prevalence of skin involvement in vasculitis, visible character and, finally, the easy accessibility of the skin for both physical examination and biopsy offers important advantages for prompt disease recognition and diagnosis. Thus, dermatologists are privileged to diagnose the disease earlier and more effectively than any other discipline. As a consequence, a detailed clinical and histopathological evaluation of the skin is one of the most critical steps in diagnosing vasculitis. Besides obtaining a good medical history, laboratory and radiological evaluation methods are used in the diagnosis. In this review, a practical and algorithmic approach is aimed to assist in the diagnosis of vasculitis. However, this approach should not be seen as strict rules. This stepwise algorithmic diagnostic approach for vasculitis was developed by combining the current literature knowledge and the author's experience in this field to provide a rational framework for selecting the most appropriate among various diagnostic approaches.

Zonulin, as a marker of intestinal permeability, is elevated in IgA nephropathy and IgA vasculitis with nephritis

Background

Immunoglobulin A nephropathy (IgAN) and IgA vasculitis with nephritis (IgAV-N) are considered related diseases and share some similar clinicopathologic phenotypes. Elevated circulating galactose-deficient IgA1 (Gd-IgA1)-containing immune complexes and mucosal immunity were associated with the pathogenesis of IgAN and IgAV-N. Recently, studies have identified that the zonulin level, as a modulator of intestinal permeability, is significantly elevated in several inflammatory and autoimmune-related diseases. However, whether zonulin also plays a role in IgAN and IgAV-N is not clear.

Methods

A total of 73 IgAV-N patients, 68 IgAN patients and 54 healthy controls were assessed for circulating zonulin and Gd-IgA1 levels by enzyme-linked immunosorbent assay. The diagnostic efficiency of the combination of zonulin with Gd-IgA1 was evaluated by the area under the receiver operating characteristic curve (AUC) and integrated discrimination improvement (IDI) analysis.

Results

Compared with healthy controls, we found that both IgAV-N and IgAN patients had elevated zonulin and Gd-IgA1 levels (P < .001). Additionally, patients with IgAV-N presented with even higher circulating zonulin levels than patients with IgAN (P = .020). The addition of zonulin to Gd-IgA1 showed better predictive performance than Gd-IgA1 alone in the diagnosis of both IgAN and IgAV-N, as illustrated by a significantly increased AUC (IgAN: 0.805 versus 0.708, P = .0021; IgAV-N: 0.886 versus 0.673, P < .001) and significant IDI (IgAN: IDI 0.136, P < .001; IgAV-N: IDI 0.281, P < .001).

Conclusion

Elevated circulating zonulin levels were detected in both patients with IgAV-N and those with IgAN. Combined detection of circulating zonulin and Gd-IgA1 is recommended as a noninvasive diagnostic biomarker for IgAV-N and IgAN.

Refractory Immunoglobulin A (IgA) Vasculitis in an Elderly Patient: A Case Report

Immunoglobulin A (IgA) vasculitis is small-vessel arteritis triggered by autoimmunity and allergies. IgA vasculitis among elderly patients is rare, and there is a lack of evidence regarding the choice of medicine and treatment duration. The main treatment for IgA vasculitis is steroids which can be cured with a small dose of prednisolone without immunosuppressants. Here, we report a case of a 90-year-old patient with the chief complaint of appetite loss and purpura on the legs who was diagnosed with IgA vasculitis based on biopsy results. The patient was initially treated with prednisolone effectively but exacerbated with steroid tapering, eventually requiring the use of an immunosuppressant. This case highlights the importance of monitoring the symptoms of IgA vasculitis while tapering steroids and clarifying the timing of immunosuppressant initiation.

Navigating the initial diagnosis and management of adult IgA vasculitis: A review

Background

IgA vasculitis in adults has not been thoroughly studied. This has left a practice gap related to the management and follow-up of a population that is at an increased risk of comorbidities and potentially poor outcomes. For this reason, it is important to synthesize evidence from the current literature because this can help direct the movement for more robust studies to clarify best practice recommendations.

Objective

We sought to create a narrative review for the practicing dermatologist when diagnosing and leading the care of IgA vasculitis in adult patients.

Methods

A broad literature search was performed with a focus on articles that were published after the introduction of the most updated European Alliance of Associations for Rheumatology/Pediatric Rheumatology International Trials Organization/Pediatric Rheumatology European Society criteria.

Results

The characteristics and management guidelines for IgA vasculitis in adults have been refined, although more rigorous studies are needed to develop best practice recommendations.

Limitations

Because of the lack of sufficient randomized controlled trials on IgA vasculitis in adults, this narrative review is composed of mostly observational, descriptive studies.

Conclusion

Adults with IgA vasculitis are at an increased risk of complicated disease course, necessitating formal diagnostic assessment and clear-cut follow-up recommendations to manage and prevent poor health outcomes related to various comorbidities.

Neutrophil-to-lymphocyte ratio as an independent inflammatory indicator for poor renal prognosis in adult IgA vasculitis with nephritis

BACKGROUND

Skin-limited IgAV patients usually present self-limiting disease and good prognosis, while adult IgA vasculitis with nephritis (IgAV-N) present severe phenotype and poor prognosis. Previous studies showed that neutrophil-to-lymphocyte ratio (NLR) was an inflammatory indicator for predicting systemic involvement in children IgAV patients. In this study, we focused on adult IgAV-N patients to explore the relationship of NLR with disease phenotype and long-term renal prognosis.

METHODS

In this study, 245 IgAV-N patients, 1151 IgAN patients and 251 healthy controls were recruited. Composite endpoint was defined as 30% eGFR declined or end stage kidney disease.

RESULTS

IgAV-N patients presented increased white blood cells (WBC), neutrophils (NE), platelet-to-lymphocyte ratio (PLR), and NLR levels, while decreased lymphocyte (LY) than healthy controls. When compared to clinical and pathological features matched IgAN patients, IgAV-N patients still showed higher WBC, NE, and NLR levels. NLR showed the best performance for the diagnosis of IgAV-N with the highest area under the ROC curves (0.738). IgAV-N patients in high NLR group (>2.41) presented with sever baseline manifestations and more acute pathological lesions than low NLR group (≤2.41). 77 patients with regular follow-up were used for survival analysis. After adjusting some well-known risk factors, NLR levels remained as an independent risk factor for poor renal outcome in adult patients with IgAV-N (HR, 1.913; 95% CI, 1.314 to 2.787, P = 0.001).

CONCLUSIONS

NLR levels were associated with the clinical and pathological phenotypes, and NLR may serve as an independent risk factor for poor renal outcome in adult IgAV-N patients.

Cutaneous vasculitis and vasculopathy in the era of COVID-19 pandemic

Cutaneous vasculitides encompass a heterogeneous group of clinicopathological entities, which may occur as single-organ vasculitis of the skin or present as skin-limited variant of systemic vasculitis (i.e., skin-limited ANCA-associated vasculitis), and are triggered by various factors, including infections, drugs and vaccines. The COVID-19 pandemic has challenged us with a variety of both disease- and vaccine-associated skin manifestations, including vasculitis. Among the latter, cutaneous small-vessel vasculitis, previously known as leukocytoclastic vasculitis, seems to be the most reported in either scenario, i.e., natural infection and vaccination. Vasculopathy without true vasculitic changes on histology develops in but a minority of cases, mostly severe/critical COVID-19 patients, and appears to be the result of endothelial injury due to pauci-immune thromboembolic mechanisms. Herein, we provide an overview of the available literature on COVID-19-associated and anti-SARS-CoV-2-vaccine-associated cutaneous vasculitis. Although evidence is mostly limited to isolated reports, with a proportion of cases lacking histopathological confirmation, ample overlap with pre-pandemic forms is shown.

Differentialdiagnose Vaskulitis und Vaskulopathie aus dermatologischer Sicht

Vaskulopathien und Vaskulitiden stellen diagnostisch und therapeutisch eine interdisziplinäre Herausforderung dar. Zugrunde liegen unterschiedliche pathophysiologische Mechanismen, die zu vielfältigen klinischen Krankheitsbildern führen können und therapeutisch unterschiedliche Ansätze erlauben. Sowohl Vaskulitiden als auch Vaskulopathien müssen nicht zwangsläufig mit einer Systembeteiligung einhergehen, sondern können auch als rein kutane Varianten auftreten. Aufgrund mangelnder pathognomonischer Laborparameter ist die Diagnose häufig klinisch zu stellen. Dieser Artikel soll den differentialdiagnostischen Blick, insbesondere auf die kutanen Manifestationsformen bei Vaskulopathien und Vaskulitiden, schärfen.

Autoimmune Disease Classification Based on PubMed Text Mining

Autoimmune diseases (AIDs) are often co-associated, and about 25% of patients with one AID tend to develop other comorbid AIDs. Here, we employ the power of datamining to predict the comorbidity of AIDs based on their normalized co-citation in PubMed. First, we validate our technique in a test dataset using earlier-reported comorbidities of seven knowns AIDs. Notably, the prediction correlates well with comorbidity (R = 0.91) and validates our methodology. Then, we predict the association of 100 AIDs and classify them using principal component analysis. Our results are helpful in classifying AIDs into one of the following systems: (1) gastrointestinal, (2) neuronal, (3) eye, (4) cutaneous, (5) musculoskeletal, (6) kidneys and lungs, (7) cardiovascular, (8) hematopoietic, (9) endocrine, and (10) multiple. Our classification agrees with experimentally based taxonomy and ranks AID according to affected systems and gender. Some AIDs are unclassified and do not associate well with other AIDs. Interestingly, Alzheimer’s disease correlates well with other AIDs such as multiple sclerosis. Finally, our results generate a network classification of autoimmune diseases based on PubMed text mining and help map this medical universe. Our results are expected to assist healthcare workers in diagnosing comorbidity in patients with an autoimmune disease, and to help researchers in identifying common genetic, environmental, and autoimmune mechanisms.

Adult-Onset IgA Vasculitis Presenting as an Unusual Rash and Pancolitis

A 47-year-old female presented with complaints of abdominal pain and a history of new-onset maculopapular rash. A workup including laboratory and imaging studies, colonoscopy, and biopsy was performed that led to the diagnosis of adult-onset IgA vasculitis. The patient responded well to intravenous methylprednisolone and was followed up as an outpatient where she continued with oral methylprednisolone and azathioprine. This case is noteworthy for the unusual adult-onset presentation with primarily gastrointestinal symptoms and atypical rash pattern. Furthermore, while very effective in this patient, the use of corticosteroids is a treatment decision that has some controversy in the current literature.

Sudden Onset of IgA Vasculitis Affecting Vital Organs in Adult Patients following SARS-CoV-2 Vaccines

IgA vasculitis is an immune complex-mediated small-vessel vasculitis that mainly occurs in children and is characterized by palpable purpura, arthralgia, abdominal pain, and glomerulonephritis. We report three cases of new-onset IgA vasculitis involving major organs in adult patients after they received either the ChAdOx1 viral vector (Oxford/AstraZeneca) vaccine or the messenger RNA-1273 (Moderna) vaccine. These cases suggest that COVID-19 vaccines have the potential to trigger IgA vasculitis and indicate that physicians need to monitor for this possible complication.

Proteomic Study on the Reproductive Toxicity of Tripterygium Glycosides in Rats

Tripterygium glycoside tablet (TGT) is a common clinically used and effective non-steroidal immunosuppressant. However, its reproductive toxicity limits its application in pediatric immune diseases, warranting the study of the molecular mechanism behind its reproductive toxicity. In the present study, 4-week-old male Sprague Dawley (SD) rats were provided TGT through continuous gavage with a clinically equivalent dose of 12 mg/kg for 12 weeks. The reproductive toxicity of TGT was recorded, and its toxicity mechanism was verified through experimental validation and proteomics analyses. Our results demonstrated that TGT could significantly reduce the testosterone level in the serum as well as the concentration and survival rate of sperms. Pathological sections of the testis revealed that TGT could reduce spermatocytes at different levels and make the convoluted meridians vacuolated. Based on tandem mass tag (TMT)-labeled quantitative rats testicular tissue proteomics, 34 differential proteins were screened, involving protein digestion and absorption, PPAR signaling pathway, PI3K-Akt, and other pathways, among which PI3K-Akt plays an important role in the study of reproductive injury. Western blotting results revealed that TGT could significantly downregulate the Col1A1, Col1A2, p-PI3K, and p-Akt expressions and inhibit the expression of proteins related to the PI3K-Akt signaling pathway. In summary, the clinically equivalent dose of TGT induced reproductive toxicity of 4-week-old male SD rats, possibly in relation to the inhibition of the PI3K-Akt pathway expression.

Blood transthyretin for predicting immunoglobulin A vasculitis nephritis outcome in children

BACKGROUND

IgA vasculitis is characterized by inflammation of the blood vessels, which can result in microvascular destruction and consequently renal damage. Transthyretin is a newly discovered angiogenesis regulator in promoting microvascular regeneration. This indicates that transthyretin may act as a potential predictor of IgAV as well as IgAVN.

METHODS

This retrospective study included 125 patients newly diagnosed as IgAV with demographic and laboratory parameters. Of these, 78 patients had demonstrated internal organ damage and 47 patients with only skin and joint injury. Of 78 patients with organ impairment, 27 were diagnosed of renal involvement. Then we evaluated the relationship between NLR, total protein, albumin, globulin, transthyretin, B lymphocyte counts and the severity of IgAV.

RESULTS

For patients with internal organ or renal involvement, the level of transthyretin were lower than non-internal organ damage group (p < 0.001 for both group). Remarkably, the NLR was only higher in patients with internal organ damage group (p = 0.019). Logistic regression analysis showed that NLR and transthyretin both were risk factors for internal organ involvement (OR = 1.768, 0.973 separately), and only transthyretin is the independent risk for renal involvement (OR = 0.981, p < 0.05). The ROC analysis showed an AUC of 0.626 for NLR, 0.815 for transthyretin in predicting organ damage, 0.755 for transthyretin in patients with renal involvement (p < 0.05, to all parameters).

CONCLUSIONS

Transthyretin is a better predictor in predicting internal organ or renal involvement than NLR, and low plasma transthyretin concentration can increase the risk of renal involvement in IgAV patients.

An Evaluation of Choroidal and Retinal Nerve Fiber Layer Thicknesses Using SD-OCT in Children with Childhood IgA Vasculitis

Background: We aimed to evaluate choroidal and retinal nerve fiber layer (RNFL) thicknesses in children undergoing the childhood IgA vasculitis (IgAV). Methods: Fifty-two patients with IgAV aged 1−6 years and 54 healthy children were included. Cases’ age, sex, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), RNFL thicknesses, and choroidal thickness values were recorded. Results: Median foveal center choroidal thickness was 374.0 µm (315.0 to 452.0 µm) in the IgAV group and 349.5 µm (285.0 to 442.0 µm) in the control group (p = 0.001). Median average RNFL thickness was 110.0 µm (91.0 to 134.0 µm) in the IgAV group and 104.0 µm (89.0 to 117.0 µm) in the control group (p < 0.001). Choroidal and RNFL thicknesses were significantly greater in all quadrants in the IgAV group than in the control group. No correlation was determined between ESR or CRP and foveal center choroidal and average RNFL thicknesses. Conclusions: Our findings show that choroidal and RNFL thicknesses increased significantly in children undergoing childhood IgA vasculitis compared to the healthy control group. These findings show that the choroid and RNFL are also affected by the inflammatory process in IgAV, which is a systemic vasculitis. We think that the choroidal and RNFL thicknesses can be used as a biomarker for childhood IgAV.

IgA vasculitis nephritis

PURPOSE OF REVIEW

The purpose of this update is to summarize current knowledge on the pathophysiology of immunglobulin A (IgA) vasculitis nephritis (IgAVN) as well as to critically review evidence for established therapeutic regimes and available biomarkers. An additional purpose is to raise the discussion what could be done to further improve our understanding of IgAVN, identify patients at risk for adverse outcome and increase the evidence for therapy recommendations.

RECENT FINDINGS

Clinical and experimental studies have established the concept of a multilevel pathogenesis. Toll-like-receptor activation, B cell proliferation, micro-RNAs and complement activation have been identified or confirmed as potential therapeutic targets which can modify the course of the disease. Currently, kidney injury molecule-1, monocyte chemotactic protein-1, N-acetyl-β-glucosaminidase, and angiotensinogen are the most promising urinary biomarkers for early diagnosis of renal involvement in IgA vasculitis.

SUMMARY

Close surveillance of all IgAV patients for renal involvement is recommended. Given the multilevel pathogenesis, early treatment of even mild cases should be initiated. Further therapeutic options should be considered in case first-line therapy (mostly corticosteroids) has no effect. The evidence supporting current therapeutic regimes is predominantly based on expert opinion. Prospective studies are needed and should involve substances inhibiting B cell proliferation and complement activation.

Extensive cutaneous leukocytoclastic vasculitis after Sinopharm vaccine: case report and review of the literature

Cutaneous leukocytoclastic vasculitis (LCV) has been reported as a rare form of cutaneous reaction to different SARS-Cov-2 vaccines. Herein, we present the first case of cutaneous LCV following BBIBP-CorV (Sinopharm) vaccine, that occurred in a female patient with no prior comorbidities. A literature review about similar cases following different COVID-19 vaccines is discussed. This article is protected by copyright. All rights reserved.

SARS‐CoV ‐2 Vaccination‐Induced Cutaneous Vasculitis: Report of two new cases and literature Review

Currently the most powerful tool in combating the COVID‐19 pandemic is vaccination against SARS‐CoV‐2. A growing percentage of the world's population is being vaccinated. Various vaccines are worldwide on the market. Several adverse reactions have been reported as a part of post‐marketing surveillance of COVID‐19 vaccines. Among the possible adverse events, cutaneous vasculitis has occasionally been reported. We present a narrative review on cutaneous vasculitis related to COVID‐19‐vaccination to summarize clinical findings, histopathology, treatment and outcome. We searched for “COVID vaccine”, “COVID vaccination” AND “cutaneous vasculitis” in PUBMED. Articles in English have been selected, from inception to December 2021, and analyzed for patient's characteristics, type of vaccine, time of appearance of cutaneous vasculitis and clinico‐histopathologic type. Treatment and outcome have also been considered in this narrative review. Two new unpublished cases of ours were added. Cutaneous vasculitis is a rare adverse event to COVID‐19 vaccination. It has been observed with mRNA and adenovirus‐vector vaccines. IgA vasculitis, lymphocytic and ANCA‐associated vasculitis, leukocytoclastic and urticarial vasculitis have been reported. This adverse event can occur after first or second shot. Most cases run a mild to moderate course. Cornerstone of medical treatment are systemic corticosteroids. Complete remission could be achieved in most patients. Vasculitis may not be considered as a contraindication of vaccination, being uncommonly reported and shows a favorable prognosis. The benefit of the vaccination remains high especially for immunocompromised patients. COVID‐vaccine induced vasculitis is important in the differential diagnosis of purpuric and vasculitis disorders.

A Review of the Mechanism of Vascular Endothelial Injury in Immunoglobulin A Vasculitis

Immunoglobulin A (IgA) vasculitis (IgAV), also known as Henoch-Schönlein purpura, is the most common form of childhood vasculitis. It is characterized by cutaneous hemorrhage, resulting from red blood cell leakage into the skin or mucosae, possibly caused by damage to small blood vessels. These acute symptoms usually disappear without treatment. Endothelial cells are distributed on the inner surfaces of blood vessels and lymphatic vessels, and have important functions in metabolism and endocrine function, as well as being the primary targets of external stimuli and endogenous immune activity. Injury to endothelial cells is a feature of IgA vasculitis. Endothelial cell damage may be related to the deposition of immune complexes, the activation of complement, inflammatory factors, and chemokines, oxidative stress, hemodynamics, and coagulation factors. Both epigenetic mechanisms and genetic diversity provide a genetic background for endothelial cell injury. Here, research on the role of endothelial cells in allergic IgA vasculitis is reviewed.