Epidemiology of immunoglobulin A vasculitis (Henoch-Schönlein): current state of knowledge. Curr Opin Rheumatol. 2013;25:171-178. [PMID: 23318735 DOI: 10.1097/bor.0b013e32835d8e2a]

Study on the correlation between intestinal flora and cytokines in children with Henoch-Schönlein purpura

BACKGROUND

The pathogenesis of Henoch-Schönlein purpura (HSP) is complex. It is currently believed that the development of HSP involves abnormalities in humoral immunity and cellular immunity. The intestinal microbiota has a powerful regulatory effect on the human immune system and has been shown to serve a significant role in the pathogenesis of various immune-mediated disorders. This study examines changes in intestinal flora and cytokines(IFN-γ, IL-4, IL-10, and IL-17) in children with HSP and explores their correlation, offering fresh insights for the prevention and treatment of HSP.

METHODS

Blood and stool specimens were collected from 25 healthy children (control group) and 27 children with HSP (observation group). Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of cytokines IFN-γ, IL-4, IL-17, and IL-10 in the serum of all the study participants, and the 16S rRNA gene sequencing combined with high-throughput sequencing technology was used to analyze the intestinal flora of the study subjects. Finally, the correlation between serum cytokines and gut microbiota was analyzed in the children with HSP.

RESULT

1)The serum levels of IL-4 and IL-17 in the observation group were higher than those in the control group, while the levels of IFN-γ and IL-10 were lower than those in the control group. 2) At the level of phylum, the abundance of Fusobacteria and Verrucomicrobia was higher than that in the control group, while the abundance of Firmicutes was lower than that of the control group, and the differences were statistically significant (P < 0.05); At the level of genus, the abundance of Prevotella and Akkermansia were higher than the control group, while the abundance of Bifidobacterium, Blautia, and Clostridium XlVa was lower than that in the control group, and the differences were all statistically significant (P < 0.05); At the species level, the abundance of Akkermansia muciniphila, Prevotella copri, and Subdoligranulum variabile was higher than that of the control group, while the abundance of Bifidobacterium pseudolongum, Brautella Weiss, and Bacteroides fragilis was lower than that in the control group, and the differences were statistically significant (P < 0.05). 3) The abundance of Blautia and Blautia wexlerae in the observation group was positively associated with the IL-10 level (r = 0.522, r = 0.578, P < 0.01).

CONCLUSION

Disturbances in intestinal flora and changes in serum cytokines IFN-γ, IL-4, IL-10, and IL-17 were present in children with HSP. The abundance of Blautia and Blautia wexlerae in the gut microbiota of children with HSP was positively correlated with serum IL-10 levels.

Epigastric pain of unknown origin, esophageal and gastric involvement: a Henoch-Schönlein Purpura case report

Henoch-Schönlein Purpura (HSP) is an acute systemic vasculitis that primarily affects the skin, gastrointestinal tract, kidneys and joints. It predominantly occurs in children but can occur at any age. We report a case of 48-year-old male patient suffering from unexplained epigastric pain alternating between relapses and remissions. The patient's initial clinical manifestation was atypical, starting with severe epigastric pain, without cutaneous purpura, and with normal rheumatologic and immunologic markers, making diagnosis difficult. The patient was eventually diagnosed with HSP. This case highlights the importance of considering this diagnosis in patients with unexplained abdominal pain and emphasize the role of endoscopy in diagnosing complex cases.

Construction and diagnostic efficacy assessment of the urinary exosomal miRNA-mRNA network in children with IgA vasculitis nephritis

This study aimed to comprehensively evaluate the diagnostic potential of urinary exosomal microRNA (miRNA) in IgA vasculitis (IgAV) kidney injury by meticulously comparing the miRNA expression profiles in urine exosomes between children diagnosed with IgAV and those with IgA vasculitis nephritis (IgAVN). Urine samples were obtained from children with IgAV who were treated at our hospital from October 2022 to October 2023. These samples were then categorized into the IgAV group and the IgAVN group. High-throughput sequencing and bioinformatics analysis techniques were employed to conduct a thorough analysis of the differentially expressed miRNAs between the two groups. Additionally, the correlation between urinary exosomal miRNA and clinical parameters was evaluated. A total of 57 urinary exosomal miRNAs exhibited differential expression between the IgAV and IgAVN groups. Specifically, in the IgAVN group, 42 miRNAs were upregulated, while 15 were downregulated. Lasso regression analysis and ROC analysis identified five candidate urinary exosomal miRNAs with high diagnostic accuracy. A prediction of 95 target genes related to the candidate miRNAs led to the construction of an exosomal miRNA-mRNA regulatory network consisting of four key miRNAs and ten hub genes. Gene function and metabolic pathway analyses indicated that these ten hub genes were predominantly enriched in pro-fibrotic and inflammatory pathways. The analysis incorporating clinical parameters demonstrated a significant correlation between hsa-miR-383-5p and urinary protein levels. This research identified exosomal miRNAs and mRNAs with differential expression patterns associated with IgAVN and constructed the corresponding exosomal miRNA-mRNA network. It was determined that hsa-miR-3065-5p, hsa-miR-383-5p, hsa-miR-25-3p, and hsa-miR-450b-5p might mediate the pathogenesis of IgAVN by targeting pro-fibrotic and inflammatory pathways. Among them, exosomal hsa-miR-383-5p is highly likely to serve as a novel non-invasive biomarker for assessing the disease status of IgAVN, thereby offering new perspectives on the non-invasive diagnosis and treatment of IgAVN.

A case of de novo glomerulonephritis following COVID-19 in a patient with preexistent IgA vasculitis

During the unprecedented COVID-19 outbreak, new-onset or relapsing glomerulonephritis, such as ANCA-associated glomerulonephritis and Immunoglobulin A (IgA) nephropathy, following COVID-19 has been reported. However, to date, the association of COVID-19 with preexistent IgA vasculitis (IgAV) remains unclear. Here, we present the case of a 20-something old Japanese woman with preexistent IgAV who newly developed glomerulonephritis following COVID-19. At the diagnosis of IgAV, she had cutaneous purpura, joint pains, and gastrointestinal symptoms, but no signs of kidney involvement. Three months ago, she was tested positive for COVID-19 and subsequently developed hematuria and proteinuria. She was then admitted to our hospital and renal biopsy showed glomerular mesangial expansion and hypercellularity and cellular and fibrocellular crescents, accompanied by diffuse IgA and C3 deposits. With the diagnosis of de novo IgAV nephritis, the patient was treated with intravenous methylprednisolone followed by oral prednisolone. She had favorable responses to this treatment and has achieved and maintained the remission of hematuria and proteinuria after initiation of glucocorticoid therapy. Our case highlights that immune response to SARS-CoV-2 infection could trigger the onset of glomerulonephritis in the IgAV patients who have no renal involvement.

Single-cell transcriptomics reveals the alteration of immune cell profile in peripheral blood of Henoch-Schonlein purpura

Henoch-Schönlein purpura (HSP) is an autoimmune vasculitis affecting multiple organs, and the understanding of circulating immune cell types and their states associated with disease subtypes of HSP remains incomplete. Here, we performed a comprehensive assessment of peripheral blood mononuclear cells of healthy donors and HSP patients, using both single-cell RNA sequencing and multiparameter flow cytometry. We revealed that HSP patients exhibited broad immune activation, evidenced by increased proportions of Effector memory CD8+ T, CD14+ monocytes, Tfh, Th2, Th17, Plasma, and B cells and decreased proportions of Naïve CD4+ T, Treg, Th1, and NK cells. Notably, we identified that cytotoxic effector T cell subsets were enriched in skin and renal type of HSP, whereas Plasma, B, and Tfh cells were expanded in joint and abdominal type of HSP. In conclusion, our findings highlight the dynamic nature of immune responses throughout the progression of HSP with different clinical manifestations.

Adenovirus: a possible trigger for IgA vasculitis in children

IgA vasculitis (IgAV), also called Henoch-Schönlein purpura (HSP), is an immune complex vasculitis characterised by IgA1-dominant immune deposits affecting small vessels (predominantly capillaries, venules or arterioles). It often involves the skin and gastrointestinal tract, frequently causes arthritis and rarely causes vasculitis in the kidney indistinguishable from IgA nephropathy. It usually presents as a purpuric non-blanching rash mostly on the lower limbs, although it may extend to the upper limbs and the trunk, and more rarely to the face. Respiratory tract infection or a history of exposure to antigens from certain foods, insects, drugs or vaccines may trigger the pathogenesis of IgAV. Adenovirus mostly causes acute respiratory diseases and occasionally causes gastroenteritis. Literature on the adenovirus as a trigger or direct involvement in the onset of IgAV is scarce. We report a few cases where IgAV is associated with adenovirus infection, and more research is required to establish this association.

IgA vasculitis nephritis-outcomes in adult-onset disease

OBJECTIVES

IgA vasculitis (IgAV) in adults has been relatively under-investigated. Since outcomes are worse in other forms of vasculitis with increasing age, we investigated the outcomes of IgAV comparing younger adults (18-34), middle-aged adults (35-64) and elderly patients (≥64 years) focusing on kidney outcomes.

METHODS

We identified patients with renal biopsy-confirmed IgAV nephritis and collected data regarding clinical features and progression to end stage kidney disease (ESKD). The relationship between patient factors and ESKD was analysed by regression.

RESULTS

We identified 202 cases, 34% aged 18-34, 43% aged 35-64 and 23% elderly (>64 years). Median follow-up was 44 months. Elderly patients were more likely to present with ESKD (23.9%) compared with middle-aged (13.7%) and younger adults (2.9%) (χ2 11.6, P = 0.002). In patients with independent kidney function at biopsy, there was no difference in outcomes between age groups. Male gender, Black ethnicity, diabetes, histological evidence of chronic renal damage and estimated glomerular filtration rate < 30 ml/min were risk factors for development of ESKD. In this observational study 68.3% of patients received glucocorticoids and 56.9% additional immunosuppression.

CONCLUSION

Elderly patients with IgAV are more likely to have ESKD at presentation, but there is no difference in renal survival between age groups, among those presenting with independent renal function. Renal impairment at biopsy is an independent risk factor for subsequent development of ESKD. There is significant variability in the timing of kidney biopsy and management of these patients among specialist centres. Young adults have outcomes more in keeping with childhood IgAV.

The Impact of Infectious Diseases on Clinical Characteristics and Immunological Correlations in Pediatric Henoch-Schönlein Purpura: A Five-Year Retrospective Study

Background/Objectives: Immunoglobulin A (IgA) vasculitis (IgAV), classically known as Henoch-Schönlein purpura (HSP), is a type of nonthrombocytopenic small-vessel vasculitis. HSP is the most frequent kind of systemic vasculitis in children, characterized by purpura, arthritis or arthralgia, gastrointestinal pain, and kidney dysfunction. The aim of our research was to investigate and observe the clinical characteristics of children diagnosed with HSP and to explore the correlation between infectious diseases and HSP. Furthermore, this retrospective study considered other factors, such as demographic characteristics (sex, area/environment, and age), and their effect on the pediatric population diagnosed with HSP. Methods: To answer this question, we conducted a five-year hospital-based retrospective study that included 144 hospitalized children who were diagnosed with HSP during hospitalization. Measurements of immunological panels (IgA, IgM, IgG, and IgE), C3, C4, C-reactive protein, fibrinogen, and hematite sedimentation rate (VSH) determined using blood samples revealed that there is a strong correlation between the elements of the immunological panel and the HSP manifestations. Results: Additionally, elevated IgG and normal IgA serum levels in pediatric HSP patients are strongly associated with infectious diseases. Conclusions: Notably, patients with infectious diseases exhibited high IgG and normal IgA serum levels post-treatment and a higher risk of relapses.

Clinical characteristics and risk factors analysis of abdominal symptoms in IgA vasculitis patients: a retrospective cohort study

About 50% of children with IgA vasculitis (IgAV) have abdominal symptoms, usually colic mimic to acute abdomen. Since signs and symptoms of vasculitis may appear in any order, this may affect the diagnosis of children whose abdominal symptoms precede the appearance of purpura. It is necessary to identify the risk factors, pathogenesis, and specific biomarkers to improve the prevention and management of IgAV patients with abdominal symptoms. All the 278 patients were children who had been diagnosed with IgAV in Nanyang Central Hospital between January 2018 and December 2018. The patient's age, gender, clinical manifestations, laboratory examination, and medical history were retrospectively collected. All the patients were divided into two groups based on whether they had abdominal symptoms. Ridge regression and multivariate logistic regression model were used to find risk factors of IgAV patients with abdominal symptoms. Of the 278 patients, 54 patients had abdominal symptoms, and the remaining 224 patients had no abdominal symptoms. Patients with abdominal symptoms had a lower proportion of infections and higher IgM concentrations than patients with other symptoms. For patients over 12 years of age, platelet counts were lower in patients with abdominal symptoms. In addition, basophil count was identified as a protective factor, while IgM was identified as a risk factor. Infections, platelet counts, basophil count, and IgM concentration may be associated with abdominal symptoms in IgAV patients. Basophils and IgM may be involved in the pathological mechanism of abdominal symptoms.

National recommendations for the management of children and young people with IgA vasculitis: a best available evidence, group agreement-based approach

OBJECTIVE

IgA vasculitis (IgAV) is the most frequently experienced subtype of vasculitis seen in children. Most children fully recover, however, complications including chronic kidney disease are recognised. The aim of this project was to use a best available evidence, group agreement, based approach to develop national recommendations for the initial management of IgAV and its associated complications.

METHODS

A fully representative multiprofessional guideline development group (GDG), consisting of 28 members, was formed and met monthly. Graded recommendations were generated using nationally accredited methods, which included a predefined scope, open consultation, systematic literature review, evidence appraisal, review of national or international guidelines and a period of open consultation. Audit measures and research priorities were incorporated.

RESULTS

The IgAV GDG met over a 14-month period. A total of 82 papers were relevant for evidence synthesis. For the initial management, four topic areas were identified with five key questions generating six graded recommendations related to classification, specialist referral and musculoskeletal involvement. For the associated complications, five topic areas with 12 key questions generated 15 graded recommendations covering nephritis, gastrointestinal and testicular involvement, atypical disease and follow-up. Open consultation feedback was incorporated. The guidelines were endorsed by the UK Kidney Association and Royal College of Paediatrics and Child Health and are available online.

CONCLUSION

Despite IgAV being a rare disease with limited evidence, a national standardised approach to the clinical management for children and young people has been achieved. This should unite approaches to care and act as a foundation for improvement.

Effective treatment with intravenous immunoglobulin for Henoch-Schönlein purpura with refractory gastrointestinal symptoms in an adolescent: A CARE-compliant case report

RATIONALE

This article presents a complex case of refractory Henoch-Schönlein purpura (HSP), initially manifesting with complex gastrointestinal (GI) symptoms, and discusses diagnostic and therapeutic challenges encountered. It aims to enhance understanding of the disease and provide evidence for the potential efficacy of intravenous immunoglobulin (IVIG) treatment in this condition.

PATIENT CONCERNS

A 16-year-old male patient presented with persistent abdominal pain, nausea, vomiting, and constipation for 8 days, leading to hospital admission.

DIAGNOSES

Establishing a definitive diagnosis was challenging initially due to the absence of typical petechiae. However, the appearance of characteristic petechiae subsequently confirmed the diagnosis of HSP.

INTERVENTIONS

Initial treatment with methylprednisolone sodium succinate for 3 days failed to elicit improvement. Subsequently, IVIG was introduced as a combination therapy.

OUTCOMES

Following the combined administration of IVIG, the patient experienced complete resolution of abdominal pain, petechiae, and arthralgia within 4 days.

LESSONS

This case highlights the importance of considering HSP in the differential diagnosis of patients with complex GI symptoms. Furthermore, it suggests that IVIG may be a valuable therapeutic option for HSP patients with refractory GI symptoms. High-quality comparative trials are needed to establish more definitive evidence for the effectiveness of IVIG and to develop specific treatment guidelines.

SARS-CoV-2 as a trigger of IgA vasculitis: a clinical case and literature review

Coronavirus Disease 2019 (COVID-19), caused by SARS-CoV-2, has negatively affected global health. COVID-19 has been associated with a variety of autoimmune and inflammatory disorders, complicating its respiratory manifestations. SARS-CoV-2 triggers inflammatory reactions which may involve multiple organs and systems. The proof for IgA involvement in the immune reactions to coronavirus infection is growing, particularly in the case of IgA immune complex deposition diseases such as IgA vasculitis (IgAV) and IgA nephropathy.This report presents a case of IgAV caused by SARS-CoV-2 in a 53-year-old man. His symptoms included papillomatous, bright red rashes, urticaria throughout the body, aphthous stomatitis, pain in all joints and muscles, weakness, malaise, abdominal pain, face swelling, and arterial hypertension (160/100 mmHg). He received intravenous methylprednisolone (250 mg) and then oral methylprednisolone (16 mg) treatment, which improved his condition. This improvement included the disappearance of abdominal and joint pain and skin rashes.This article also provides an overview of published cases of IgAV after SARS-CoV-2. It may alert rheumatologists and allied specialists of clinical features of IgAV and guide them how to diagnose and treat this disease.

Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis

Immunoglobulin A vasculitis (IgAV), previously known as Henoch-Schönlein purpura, is the most common form of systemic vasculitis in childhood. The primary organs involved are the skin, gastrointestinal (GI) tract, joints, and kidneys. The spectrum of GI involvement in IgAV ranges from being mild and self-limited to severe manifestations often requiring surgical intervention. Galactose-deficient IgA1 on the immunoglobulin hinge region and its immune complexes are thought to play a central pathogenetic role in IgAV, however, an association between such molecules and specific GI mucosal damage remains unclear. GI endoscopy (both upper and lower) shows a variety of mucosal findings, many of which are not specific for IgAV. In upper GI endoscopy, however, the mucosal features can be diagnostic when found localized in the more distal part of upper GI tract (second and/or third parts of the duodenum). Abdominal computed tomography and capsule endoscopy have demonstrated that the small intestine is most commonly involved in IgAV. The GI mucosal involvement when evaluated microscopically shows IgA deposition which is histologically diagnostic. Conversely, leukocytoclastic vasculitis is less useful. Since the 1960s, cases of duodenojejunitis, in which IgAV was suspected but evident purpura was not dermatologically present, have often been labeled as "idiopathic". In a pediatric case series, IgA enteropathy, without dermatological manifestations (i.e., purpura), was reported to have similar symptoms, as well as endoscopic characteristics and immunohistological findings as in IgAV. Subsequently, several case reports provide additional supportive evidence that IgA enteropathy must be a variant of IgAV. Thus, the immunologically driven auto-immune vasculitis results in the symptom complex dependent on the organ system involved, and the subsequent clinical features which are manifested. Present classification criteria are useful and universally available for diagnosing IgAV. However, based upon current knowledge including IgA enteropathy, minor modification of the IgAV criteria is proposed in the review.

An Unusual Case of Abdominal Pain in a Geriatric Man

BACKGROUND

Immunoglobulin A vasculitis, historically known as Henoch-Schönlein purpura, is a rare form of autoimmune-induced vasculitis most common in children. This disease is characterized by a purpuric rash, arthritis, digestive tract complication, and renal inflammation (Hopkins).

CASE REPORT

We present the case of a 78-year-old man in the emergency department with findings of weakness, abdominal pain, and bloody diarrhea for 3 days and a new-onset bilateral lower extremity rash. Diagnostic imaging and labs diagnosed this patient with immunoglobulin A vasculitis (IgAV) with associated acute kidney injury and abdominal mesenteric edema. Why Should an Emergency Physician be Aware of This? Recognition of IgAV by emergency physicians and assessment of multiple organ involvement is critical to expedite treatment and minimize complications. Particularly, physicians should consider and recognize the increased severity and different presentation of IgAV in adults in comparison with the more widely known manifestation in children.

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.

Insight into the Interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in IgA Vasculitis (IgAV)

The pathogenesis of IgAV, the most common systemic vasculitis in childhood, appears to be complex and requires further elucidation. We aimed to investigate the potential role of galactose-deficient immunoglobulin A1 (Gd-IgA1), high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE) and protocadherin 1 (PCDH1) in the pathogenesis of IgAV. Our prospective study enrolled 86 patients with IgAV and 70 controls. HMGB1, RAGE, Gd-IgA1 and PCDH1 in serum and urine were determined by the enzyme-linked immunosorbent assay (ELISA) method at the onset of the disease and after a six-month interval in patients and once in the control group. Serum concentrations of HMGB1, RAGE and PCDH1 and urinary concentrations of HMGB1, RAGE, Gd-IgA1 and PCDH1 were significantly higher in patients with IgAV than in the control group (p < 0.001). Concentrations of HMGB1 (5573 pg/mL vs. 3477 pg/mL vs. 1088 pg/mL, p < 0.001) and RAGE (309 pg/mL vs. 302.4 pg/mL vs. 201.3 pg/mL, p = 0.012) in the serum of patients remained significantly elevated when the disease onset was compared with the six-month follow-up interval, and thus could be a potential marker of disease activity. Urinary concentration of HMGB1 measured in the follow-up period was higher in patients with nephritis compared to IgAV without nephritis (270.9 (146.7-542.7) ng/mmol vs. 133.2 (85.9-318.6) ng/mmol, p = 0.049) and significantly positively correlated with the urine albumine to creatinine ratio (τ = 0.184, p < 0.05), the number of erythrocytes in urine samples (τ = 0.193, p < 0.05) and with the outcome of nephritis (τ = 0.287, p < 0.05); therefore, HMGB1 could be a potential tool for monitoring patients with IgAV who develop nephritis. Taken together, our results imply a possible interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in the development of IgAV. The identification of sensitive biomarkers in IgAV may provide disease prevention and future therapeutics.

Deregulation in adult IgA vasculitis skin as the basis for the discovery of novel serum biomarkers

INTRODUCTION

Immunoglobulin A vasculitis (IgAV) in adults has a variable disease course, with patients often developing gastrointestinal and renal involvement and thus contributing to higher mortality. Due to understudied molecular mechanisms in IgAV currently used biomarkers for IgAV visceral involvement are largely lacking. Our aim was to search for potential serum biomarkers based on the skin transcriptomic signature.

METHODS

RNA sequencing analysis was conducted on skin biopsies collected from 6 treatment-naïve patients (3 skin only and 3 renal involvement) and 3 healthy controls (HC) to get insight into deregulated processes at the transcriptomic level. 15 analytes were selected and measured based on the transcriptome analysis (adiponectin, lipopolysaccharide binding protein (LBP), matrix metalloproteinase-1 (MMP1), C-C motif chemokine ligand (CCL) 19, kallikrein-5, CCL3, leptin, C-X-C motif chemokine ligand (CXCL) 5, osteopontin, interleukin (IL)-15, CXCL10, angiopoietin-like 4 (ANGPTL4), SERPIN A12/vaspin, IL-18 and fatty acid-binding protein 4 (FABP4)) in sera of 59 IgAV and 22 HC. Machine learning was used to assess the ability of the analytes to predict IgAV and its organ involvement.

RESULTS

Based on the gene expression levels in the skin, we were able to differentiate between IgAV patients and HC using principal component analysis (PCA) and a sample-to-sample distance matrix. Differential expression analysis revealed 49 differentially expressed genes (DEGs) in all IgAV patient's vs. HC. Patients with renal involvement had more DEGs than patients with skin involvement only (507 vs. 46 DEGs) as compared to HC, suggesting different skin signatures. Major dysregulated processes in patients with renal involvement were lipid metabolism, acute inflammatory response, and extracellular matrix (ECM)-related processes. 11 of 15 analytes selected based on affected processes in IgAV skin (osteopontin, LBP, ANGPTL4, IL-15, FABP4, CCL19, kallikrein-5, CCL3, leptin, IL-18 and MMP1) were significantly higher (p-adj < 0.05) in IgAV serum as compared to HC. Prediction models utilizing measured analytes showed high potential for predicting adult IgAV.

CONCLUSION

Skin transcriptomic data revealed deregulations in lipid metabolism and acute inflammatory response, reflected also in serum analyte measurements. LBP, among others, could serve as a potential biomarker of renal complications, while adiponectin and CXCL10 could indicate gastrointestinal involvement.

An Investigation of the Relationship between Henoch-Schönlein Purpura and Viral Infection in Korea Using the Health Insurance Database

(1) Background: This study investigated the epidemiology and viral connections of Henoch-Schönlein purpura (HSP) using information from the Korea Disease Control and Prevention Agency and the Health Insurance Review and Assessment database. (2) Method: Between 2016 and 2019, a total of 25,443 patients with HSP were identified, with 51.3% of patients under the age of 20 years and the highest incidence in March. (3) Results: The autoregressive integrated moving average model and Granger causality test were used to analyze the association between the virus positivity detection rate and HSP incidence. (4) Conclusions: The incidence of HSP was associated with rotavirus, bocavirus, parainfluenza virus, and respiratory syncytial virus in individuals under 20 years of age, whereas adenovirus, respiratory syncytial virus, and norovirus were associated with individuals above that age.

Humoral immunoprofiling identifies novel biomarkers and an immune suppressive autoantibody phenotype at the site of disease in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a heterogeneous cancer, with minimal response to therapeutic intervention and with 85% of cases diagnosed at an advanced stage due to lack of early symptoms, highlighting the importance of understanding PDAC immunology in greater detail. Here, we applied an immunoproteomic approach to investigate autoantibody responses against cancer-testis and tumor-associated antigens in PDAC using a high-throughput multiplexed protein microarray platform, comparing humoral immune responses in serum and at the site of disease in order to shed new light on immune responses in the tumor microenvironment. We simultaneously quantified serum or tissue IgG and IgA antibody isotypes and subclasses in a cohort of PDAC, disease control and healthy patients, observing inter alia that subclass utilization in tumor tissue samples was predominantly immune suppressive IgG4 and inflammatory IgA2, contrasting with predominant IgG3 and IgA1 subclass utilization in matched sera and implying local autoantibody production at the site of disease in an immune-tolerant environment. By comparison, serum autoantibody subclass profiling for the disease controls identified IgG4, IgG1, and IgA1 as the abundant subclasses. Combinatorial analysis of serum autoantibody responses identified panels of candidate biomarkers. The top IgG panel included ACVR2B, GAGE1, LEMD1, MAGEB1 and PAGE1 (sensitivity, specificity and AUC values of 0.933, 0.767 and 0.906). Conversely, the top IgA panel included AURKA, GAGE1, MAGEA10, PLEKHA5 and XAGE3aV1 (sensitivity, specificity, and AUC values of 1.000, 0.800, and 0.954). Assessment of antigen-specific serum autoantibody glycoforms revealed abundant sialylation on IgA in PDAC, consistent with an immune suppressive IgA response to disease.

Online information-seeking behavior of Iranian web users on Google about Henoch-Schönlein purpura (HSP): an infodemiology study

BACKGROUNDS

Previous studies have indicated that users' health information-seeking behavior can serve as a reflection of current health issues within a community. This study aimed to investigate the online information-seeking behavior of Iranian web users on Google about Henoch-Schönlein purpura (HSP).

METHODS

Google Trends (GTr) was utilized to collect big data from the internet searches conducted by Iranian web users. A focus group discussion was employed to identify users' selected keywords when searching for HSP. Additionally, keywords related to the disease's symptoms were selected based on recent clinical studies. All keywords were queried in GTr from January 1, 2012 to October 30, 2022. The outputs were saved in an Excel format and analyzed using SPSS.

RESULTS

The highest and lowest search rates of HSP were recorded in winter and summer, respectively. There was a significant positive correlation between HSP search rates and the terms "joint pain" (P = 0.007), "vomiting" (P = 0.032), "hands and feet swelling" (P = 0.041) and "seizure" (P < 0.001).

CONCLUSION

The findings were in accordance with clinical facts about HSP, such as its seasonal pattern and accompanying symptoms. It appears that the information-seeking behavior of Iranian users regarding HSP can provide valuable insights into the outbreak of this disease in Iran.

New-onset systemic vasculitis following SARS-CoV-2 infection and vaccination: the trigger, phenotype, and outcome

The global health crisis caused by the COVID-19 pandemic overwhelmed the capacity of healthcare systems to cope with the rapidly spreading infection and its associated complications. Among these complications, autoimmune phenomena such as systemic vasculitis emerged as a significant challenge. Both the SARS-CoV-2 virus and the vaccines developed to combat it appeared to induce clinical manifestations resembling various types of systemic vasculitis, affecting large, medium, and small vessels. These virus- or vaccine-induced vasculitides exhibited a distinct natural history and course from de novo vasculitis, as they were more responsive to steroid therapy and some mild cases even resolved spontaneously. Notably, there have been no confirmed cases of SARS-CoV-2 infection or vaccination triggering variable vessel vasculitis like Behcet's disease or Kawasaki disease. IgA vasculitis, which is predominantly a pediatric condition, was more prevalent in adults after COVID-19 infection and they had a favorable outcome with glucocorticoid treatment. The impact of immunosuppression, especially B-cell-depleting agents, on the immunogenicity of the vaccine was evident, but there was no significant increase in the incidence of SARS-CoV-2 infection in these patients compared to the general population. Considering their relatively benign course, these post-COVID or post-vaccine vasculitides seem to be amenable to 0.8 to 1 mg/kg prednisolone or equivalent, which could be gradually tapered. The need for immunosuppression and the duration of steroid therapy should be determined on an individual basis. While the world still reels from the perils of a deadly pandemic, the aftermath continues to haunt. Our narrative review aims to explore the effects of COVID and the vaccine on systemic vasculitis, as well as the effect of disease and immunosuppression on the immunogenicity of the COVID vaccine.

Henoch-Schönlein purpura in the setting of COVID-19 infection: Two pediatrics cases and review of the literature

Henoch-Schönlein purpura (HSP) is the most common systemic vasculitis in children, often following a viral infection. Various types of rashes attributed to COVID-19 infection have been described in the literature; however, HSP has rarely been reported. We report two children with HSP associated with acute COVID-19 infection with a review of the available literature. We highlight the clinical presentation, medical management, outcome and age-related difference of reported patients. A limitation of this article is the retrospective nature, limiting full patient history and associated conditions. The findings of this review show that HSP in the setting of COVID-19 is more common in children than adults, with a male predominance, involving various body systems creating a constellation of presentations. Given that HSP can have long-term morbidity from renal disease if untreated, this review may help guide the practitioner's approach to HSP and recognition in the setting of COVID-19 infection.

Glomerulonephritis

Glomerulonephritis (GN) encompasses several disorders that cause glomerular inflammation and injury through an interplay of immune-mediated mechanisms, host characteristics, and environmental triggers, such as infections. GN can manifest solely in the kidney or in the setting of a systemic illness, and presentation can range from chronic and relatively asymptomatic hematuria to fulminant renal failure. Classic acute GN is characterized by hematuria, edema, and hypertension, the latter 2 of which are the consequence of sodium and water retention in the setting of renal impairment. Although presenting signs and symptoms and a compatible clinical history can suggest GN, serologic and urinary testing can further refine the differential diagnosis, and renal biopsy can be used for definitive diagnosis. Treatment of GN can include supportive care, renin-angiotensin-aldosterone system blockade, immunomodulatory therapy, and renal transplant. Prognosis is largely dependent on the underlying cause of GN and can vary from a self-limited course to chronic kidney disease. This review focuses on lupus nephritis, IgA nephropathy, IgA vasculitis, and postinfectious GN.

Severe gastrointestinal involvement in pediatric IgA vasculitis: a retrospective single-center cohort study in China

Objectives

The study aimed to describe the characteristics of gastrointestinal (GI) involvement in a cohort of hospitalized children with IgA vasculitis (IgAV) in China.

Method

We reviewed the records of hospitalized IgAV patients from January 2014 to December 2020 at one tertiary medical center. The patients were divided into the severe GI group and the non-severe GI group according to the presence of massive GI bleeding and complications. The clinical manifestations, laboratory factors, and treatment were analyzed between the two groups.

Results

A total of 1,179 patients were hospitalized due to IgAV. GI involvement was noted in 50% (589) of the patients, of whom 288 (48.9%) had severe GI involvement. GI complications were observed in 34 patients with IgAV with GI involvement. Rare onset age (<3 years or within 13-17 years), purpura above the waist, vomiting, high neutrophil-to-lymphocyte ratio, and decreased serum albumin were factors associated with severe GI involvement. Frequencies of renal involvement and biopsy-proven nephritis were higher in the severe GI group. The most commonly used medications were corticosteroids (100.0%) in the severe GI group. The maximum corticosteroid dose was higher (2.9 vs. 2.0 mg/kg), and more second-line therapies were needed (30.9% vs. 16.94%) in the severe GI group.

Conclusions

Severe GI involvement in children is common in our center. Rare onset age, purpura above the waist, vomiting, high neutrophil-to-lymphocyte ratio, and decreased serum albumin are associated with severe GI involvement. Patients with severe GI involvement need higher doses of corticosteroids and second-line therapy.

Immunoglobulin A Vasculitis: Contemplating Treatment for Gastrointestinal Involvement

This is a case of a 30-year-old female with a history of recent cholecystectomy who presented with a chief complaint of diffuse rash, abdominal pain, vomiting, and diarrhea. Infectious and autoimmune tests were unrevealing, but a skin biopsy confirmed the presence of immunoglobulin A (IgA) vasculitis. Worsening gastrointestinal (GI) symptoms prompted the care team to pursue upper and lower endoscopies, which were suggestive of GI involvement of IgA vasculitis. The patient responded well to corticosteroids and later had a recurrence of diarrhea which improved with cholestyramine, raising the question of a co-existent post-cholecystectomy syndrome. This case highlights the importance of having broad differential diagnoses, and establishing the extent of organ involvement in IgA vasculitis, as this can dictate the type of treatment used.

Chaihu Longgu Muli Decoction for post-stroke insomnia: A protocol for systematic review and meta-analysis

BACKGROUND

Poststroke insomnia (PSI) is a frequent complication of stroke usually as a comorbidity of poststroke depression and mainly occurs within the first 6 months after stroke.[1] Addressing PSI to improve stroke prognosis is of great value. Herbal medicine like Chaihu Longgu Muli Decoction (CLMD), which is commonly considered to be a good treatment for depression and epilepsy, has the therapeutic potential on PSI; however, insufficient systematic reviews were conducted to testify its efficacy. Therefore, the objective of this paper is to provide reliable evidence of the efficacy and safety of CLMD on PSI and a foundation for further investigation.

METHODS

The literature of clinical randomized controlled trials (RCTs) regarding CLMD for PSI published before June of 2021 will be retrieved in the databases, and 2 investigators will be asked to collect and crosscheck the data independently. For the including studies, the quality evaluation on methodology will be assessed in the light of the Cochrane Handbook for Systematic Review of Interventions V.5.1.0 as well as the quality of evidence will be evaluated by the Grading of Recommendations Assessment, Development, and Evaluation. Besides, the assessment of heterogeneity and reporting bias, the sensitivity analysis and the subgroup analysis will be conducted. Stata 15 will be applied to analyze the above data.

RESULTS

The review will conduct a high-quality synthesis on present evidence of CLMD for PSI.

CONCLUSION

The conclusion of the study will indicate whether CLMD is effective and safe for PSI.

Venous sinus thrombosis in a case of immunoglobulin A vasculitis and a systemic review of literature

OBJECTIVES

To describe venous sinus thrombosis involved in immunoglobulin A (IgA) vasculitis and identify the clinical features and imaging findings of this rare disease.

METHODS

We describe a case with venous sinus thrombosis related to IgA vasculitis, and a systematic review of previously reported cases in the literature.

RESULTS

A 10-year-old boy presented with recurrent petechiae of the lower extremities with abdominal pain, and was diagnosed as having IgA vasculitis. He had a sudden headache during the treatment of steroids, and venous sinus thrombosis was diagnosed according to magnetic resonance imaging. Venous sinus thrombosis is a rare complication of IgA vasculitis. Based on the systematic review, most of these reported cases who developed venous sinus thrombosis had multi-system involvement, which included skin, joints, gastrointestinal tract or kidneys. Sudden headache was the most common symptom of central venous sinus thrombosis. Some cases may also manifest as seizures and blindness. The sagittal sinus was the most common site of thrombosis. Magnetic resonance image, magnetic resonance venography, or computed tomography angiography were helpful for early diagnosis of this disease. Combination therapy of steroids and anticoagulation medication was effective in rapidly reliving clinical symptoms.

CONCLUSIONS

Sudden headache in patients with IgA vasculitis requires vigilance for the possibility of central venous sinus thrombosis. Anti-inflammatories combined with anticoagulant therapy were needed for these patients.

Association of Pediatric Vasculitis Activity Score with immunoglobulin A vasculitis with nephritis

BACKGROUND

Immunoglobulin A vasculitis with nephritis (IgAVN) is the most serious complication affecting long-term prognosis. Understanding the risk factors and markers for the development of IgAVN is essential. The aim of this study is to identify IgAVN-associated factors and to evaluate the usability of Pediatric Vasculitis Activity Score (PVAS) at diagnosis as an early marker for the development of IgAVN.

METHODS

We conducted a retrospective case-control study of 314 patients divided into two groups: those with nephritis (IgAVN) and without nephritis (non-IgAVN). The groups were compared in terms of clinical symptoms, laboratory values, and PVAS values.

RESULTS

In total, 18.5% of the patients had IgAVN; they were older than the non-IgAVN patients (median age was 8.8, p < 0.05). Arthritis/arthralgia, abdominal pain, and intestinal bleeding were more common, systolic and diastolic BP were higher in IgAVN (p < 0.05). CRP, serum creatinine, and urine protein/Cr, PVAS were higher, while serum albumin was lower in IgAVN (p < 0.05). The receiver operator characteristic curve (ROC) analysis showed that IgAV patients with a determined cut-off PVAS value greater than 3 had 70.7% sensitivity in predicting whether or not they would develop IgAVN. Logistic regression analysis found that PVAS > 3 and low serum albumin at the time of diagnosis were independent risk factors for IgAVN.

CONCLUSION

Our study revealed that PVAS > 3 at diagnosis is an independent predictor of IgAVN. Patients with PVAS > 3 should be followed more closely to ensure early diagnosis and management of IgAVN. A higher resolution version of the Graphical abstract is available as Supplementary information.

Classification and epidemiology of vasculitis: Emerging concepts

The recent publication of the American College of Rheumatology (ACR)-European Alliance of Associations for Rheumatology (EULAR) classification criteria for large vessel vasculitis and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) has provided modern criteria for the classification of these conditions, which incorporate contemporary methods of investigation and diagnosis. Further validation is required in independent cohorts, especially from populations that were not well represented in the development cohort. Studies of the occurrence of large vessel vasculitis report that Takayasu arteritis is a rare disease in most populations, and giant cell arteritis is the most common vasculitis in older populations. The incidence of AAV appears to have plateaued, but the prevalence is increasing as a result of lower mortality. The new classification criteria may affect the reported incidence and prevalence, and studies will be needed to confirm this. The impact of COVID-19 on the occurrence of the vasculitides is not completely known, but there is evidence of reduced occurrence of Kawasaki disease and IgA-associated vasculitis following lockdowns with reduced transmission of possible trigger infectious agents.

Adult-Onset IgA Vasculitis Associated With Pulmonary-Renal Syndrome Following COVID-19 Infection: A Case Report and Literature Review

Immunoglobulin A (IgA) vasculitis, also known as Henoch-Schönlein purpura (HSP), is an immune complex-mediated inflammation of small blood vessels that leads to tissue destruction with or without organ damage. We described a case of a 41-year-old otherwise healthy female who presented with an ascending rash distributed on both lower extremities and arthralgia. Blood testing revealed high blood urea nitrogen (BUN), creatinine, and inflammatory markers, as well as a negative autoimmune panel. Urinalysis revealed proteinuria and hematuria. A kidney biopsy was performed, which revealed abnormalities. She was started on intravenous (IV) methylprednisolone pulse therapy. Suddenly, she complained of epistaxis and became desaturated. Computed tomography revealed bilateral pleural effusion, and she was transferred to the ICU. Bronchoalveolar lavage was performed and was consistent with an increasing bloodier return. Plasma exchange was performed. The rash and clinical symptoms improved dramatically. This study reports a case of IgA vasculitis based on The European Alliance of Associations for Rheumatology/Pediatric Rheumatology International Trials Organization/Pediatric Rheumatology European Society (EULAR/PRINTO/PRES) criteria associated with pulmonary-renal syndrome following a case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

IgA Vasculitis in Japanese Patients Harboring MEFV Mutations: A Case Report and Review of the Literature

Immunoglobulin A vasculitis (IgAV) is the most common vasculitis of childhood. However, its etiology remains unknown. In the Mediterranean region, 10% of patients with IgAV harbor homozygous and compound heterozygous mutations in the Mediterranean fever (MEFV) gene. Thus, such mutations may be involved in the development of IgAV. Herein, we present a five-year-old girl presented with IgAV. She experienced prolonged abdominal pain, which was steroid-resistant. When treatment with colchicine was started, her abdominal pain resolved immediately. The serum interleukin (IL)-18 levels of the patient and other patients with IgAV and familial Mediterranean fever (FMF) were evaluated using enzyme-linked immunosorbent assay. The serum IL-18 level of the patient was higher than that of other patients with IgAV and was similar to that of patients with FMF harboring M694I mutation. Moreover, all exons of the MEFV gene were analyzed using the Sanger sequencing and the patient presented with E148Q/M694I mutation. Further, a comprehensive search of Japanese patients with IgAV harboring MEFV gene mutations in PubMed, Ichushi-Web, and Medical Online was conducted to validate the clinical characteristics of Japanese patients with IgAV harboring MEFV gene mutation. In previous studies, only five patients presented with IgAV harboring MEFV gene mutation in Japan.  The prevalence of IgAV associated with MEFV gene mutation may be low in Japan. However, MEFV gene mutations should be suspected if the symptoms of IgAV are prolonged or if patients are refractory to treatment. In such case, IL-18 monitoring and colchicine treatment may be useful for IgAV with MEFV gene mutation.

Preadolescent-versus adolescent-onset immunoglobulin A vasculitis: The impact of age on prognosis

BACKGROUND

This study aimed to investigate the characteristics of patients with preadolescent- and adolescent-onset immunoglobulin A vasculitis (IgAV) and to determine whether age affects IgAV outcomes in adolescents.

METHODS

Demographic, clinical, and laboratory data of 333 patients diagnosed with IgAV at the Department of Pediatric Rheumatology, University of Health Sciences, Ankara City Hospital, were evaluated retrospectively. The patients were classified into two groups: preadolescents (<10 years) and adolescents (10-19 years). Subgroup analyses were also performed by grouping the adolescent patients into early, middle, and late adolescent groups.

RESULTS

Of the 333 patients, 219 (65.8%) and 114 (34.2%) were preadolescents and adolescents. Palpable purpura, renal, joint, and gastrointestinal (GI) tract involvement were detected in 333 (100%), 78 (23.4%), 79 (23.7%), and 124 (37.2%) patients, respectively; testicular involvement was observed in 25 (13.3%) of 187 male patients. The frequency of renal involvement was significantly higher in the adolescent group than in the preadolescent group at the time of diagnosis (p = 0.030). Notably, joint involvement was significantly higher in the adolescent group (p = 0.001). The need for aggressive therapy was significantly higher in the adolescent group than in the preadolescent group (p = 0.003). There was no significant difference in clinical data, demographic characteristics, and laboratory findings between the adolescent subgroups (p > 0.05).

CONCLUSIONS

Immunoglobulin A vasculitis can occur at any age but the disease prognosis appears to worsen with age. The present study reported that joint involvement, kidney involvement, and the need for more aggressive treatment were higher in the adolescent group than in the preadolescent group.

Immunoglobulin a (IgA) Vasculitis in the Elderly

IgA vasculitis is a small vessel vasculitis mediated by the deposition of IgA immune complexes. It mostly occurs in children and is rare in adults, with increased severity and mortality in the latter. Its aetiology remains largely unknown, and its prognosis depends primarily on the extent of renal involvement. We present the case of a 71-year-old woman with purpuric lesions in both lower and upper limbs associated with fever, abdominal pain, vomiting and blood in her stools for the past month. The patient was diagnosed with IgA vasculitis and the full systemic involvement (renal, dermatological, intestinal, and cerebral) of the disease was identified with excellent response to parenteral corticotherapy.

IgA Vasculitis Following COVID-19 Vaccination

As new variants of SARS-CoV-2 continue to emerge worldwide, countries are striving to fully vaccinate their population in a bid to prevent severe disease, subsequent hospitalizations, and the associated strain on their healthcare systems and death. In this context, there is growing evidence of rare, potential side effects associated with COVID-19 vaccines. IgA vasculitis is a systemic, IgA-mediated vasculitis characterized by palpable purpura, arthralgia, abdominal pain, and renal involvement. It is the most common type of vasculitis in childhood, sporadically affecting the adult population. However, there have been multiple reports of IgA vasculitis following vaccination against COVID-19. Herein, we present the case of a 72-year-old patient with palpable purpura that developed two weeks after receiving the Pfizer BioNTech vaccine. Laboratory investigations revealed elevated serum creatinine (2.6 mg/dL), macroalbuminuria (8.6 g/24 h), and macroscopic hematuria. Histopathological examination confirmed necrotizing vasculitis, and a diagnosis of IgA vasculitis was established. Considering the clinical presentation, the laboratory and histopathological findings, and the time interval between the vaccination and the development of symptoms, we strongly believe that IgA vasculitis in this patient arose as a side effect of the Pfizer BioNTech vaccine.

Gastrointestinal Bleeding Induced by Immunoglobulin A Vasculitis on Post-Mild COVID-19 Patients

We describe the case of a 51-year-old man who presented with a palpable purpuric rash and associated four days of lower gastrointestinal bleeding one month after testing positive for COVID-19. Urine studies showed evidence of microscopic hematuria and an increased protein/creatinine ratio. An abdominal computed tomography scan showed distal ileitis, and a skin biopsy was significant for IgA vasculitis. Treatment with methylprednisolone was started, which led to the resolution of symptoms. Immunologic consequences of COVID-19 must not be overlooked, as they have a wide variety of presentations in diverse aged populations. IgA vasculitis is uncommon in adults, as well as gastrointestinal bleeding as a complication related to COVID-19.

IgA vasculitis update: Epidemiology, pathogenesis, and biomarkers

Immunoglobulin A vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is the most common systemic vasculitis in children, characterized by diverse clinical manifestations with a wide spectrum ranging from isolated cutaneous vasculitis to systemic involvement. The incidence of IgAV is geographically and ethnically variable, with a prevalence in autumn and winter, suggesting a driving role that genetic and environmental factors play in the disease. Although IgAV has a certain degree of natural remission, it varies widely among individuals. Some patients can suffer from severe renal involvement and even progress to end-stage renal disease. Its pathogenesis is complex and has not been fully elucidated. The formation of galactose-deficient IgA1 (Gd-IgA1) and related immune complexes plays a vital role in promoting the occurrence and development of IgAV nephritis. In addition, neutrophil activation is stimulated through the binding of IgA to the Fc alpha receptor I expressed on its surface, resulting in systemic vascular inflammation and tissue damage. Starting from the epidemiological characteristics, this article will review the role of immunological factors such as Gd-IgA1, autoantibodies, circulating immune complexes, complement system, cellular immunization, and the contributions of environmental and genetic factors in the pathogenesis of IgAV, and conclude with the major biomarkers for IgAV.

IgA vasculitis with nephritis (Henoch-Schönlein purpura) after COVID-19: A case series and review of the literature

COVID-19 most related glomerular disease to date seems to be collapsing glomerulopathy, mostly in young Afroamerican patients with APOL1 gene risk alleles. However, in our population, predominant in elderly Caucasian patients, most biopsied pathology since the beginning of the pandemic has been IgA nephritis or Schönlein-Henoch purpura. Since the description of the first case of this entity after SARS-CoV-2 infection by our research group, three more cases have arisen, which are described in the following article. In contrast to the rest of IgA vasculitis cases reported, our patients presented more renal function deterioration and all of them required immunosupresive therapy. Moreover, some showed incomplete recovery of renal function. This case series strengthens the hypothesis that SARS-CoV-2 infection may be another trigger of this pathology.

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.

IgA vasculitis with severe renal manifestation

IgA vasculitis is a rare systemic vasculitis in adults, frequently more severe than in paediatric age. It manifests with cutaneous, articular, gastrointestinal and renal involvement.We present a case of a man in his 40s diagnosed with IgA vasculitis with cutaneous, joint, gastrointestinal and renal disease. Significant proteinuria and renal biopsy findings demonstrating crescentic glomerulonephritis led to the onset of early immunosuppression with corticoid and cyclophosphamide. This case report reflects a case of more severe renal impairment due to IgA vasculitis with good outcome with the chosen therapy. The findings in the renal biopsy after treatment supported the good response to the chosen immunosuppression.

Cochlear and vestibular involvement in children with IgA vasculitis

In this study, our purpose is to evaluate cochlear and vestibular function in juveniles with IgA vasculitis using audiometry, distortion product otoacoustic emissions, and cervical vestibular evoked myogenic potential (cVEMP) tests. Forty children diagnosed with IgA vasculitis from the pediatry clinic and 40 age- and sex-matched healthy children were evaluated with distortion product otoacoustic emissions, audiometry, and cVEMP test in a tertiary hospital. The audiometry average values for both ears of the IgA vasculitis group and the control subjects were compared, and as a result, median 4.7-dB sensorineural hearing loss (SHL) was found for the IgA vasculitis group compared to the control group at 250 Hz and it was statistically significant (p < 0.001). An average of 6.4-dB SHL was detected at 8000 Hz (p < 0.001). There was a statistically significant difference among IgA vasculitis and control groups regarding measurement results of average p1-n1 latency time of both ears (0.9 ms (ms) increase, p = 0.035). In IgA vasculitis patients, the median amplitude difference of both ears' average p1 n1 was found to be 5.6 mV, statistically significantly decreased compared to the control group (p = 0.003).

CONCLUSION

This study, firstly in literature, demonstrated that IgA vasculitis may have association with hearing loss and vestibular dysfunction in children. We think this might be due to autoimmune mechanisms.

WHAT IS KNOWN

• Ig A vasculitis is a leukocytoclastic vasculitis with unknown etiology, involving the skin, joints, gastrointestinal system, kidneys, and rarely other organs. • No study has been reported for the cochlear and vestibular association of Ig A vasculitis in current literature.

WHAT IS NEW

• This study demonstrated that Ig A vasculitis may have association with hearing loss in children. • This study also demonstrated that Ig A vasculitis may have association with vestibular dysfunction in children.

An Assessment on the Effectiveness of the Immature Granulocyte Percentage in Predicting Internal Organ Involvement Among Children With Henoch-Schönlein Purpura

Henoch-Schönlein purpura (HSP) is the most common childhood systemic vasculitis. The present study aims to investigate the effectiveness of the immature granulocyte (IG) percentage as a new marker for predicting internal organ involvement in HSP. This study included 75 patients below 18 years old who were diagnosed with HSP. The mean age was 7.48±2.77 years. The male/female ratio was 1.14. The findings showed that 35 (46.7%) of the patients had an internal organ involvement. The mean IG percentage was 0.88±0.68 among the patient group with HSP internal organ involvement, while it was 0.31±0.15 in the group without internal organ involvement, and a significant difference was determined between the 2 groups (P=0.000). The findings showed that the patients with renal involvement had the highest mean IG percentage (IG; 1.00±0.21). When the cutoff value for the IG percentage was specified as 0.45 to predict internal organ involvement, the sensitivity was 77.1%, and the specificity was 85%. In this study, the findings showed that IG percentage increased among patients with internal organ involvement in HSP and that its sensitivity, specificity, and predictive values were higher in predicting internal organ involvement compared with other markers.

Lipid metabolism contribute to the pathogenesis of IgA Vasculitis

Background and objectives

The underlying mechanism of IgA vasculitis (IgAV) and IgA vasculitis with nephritis (IgAVN) remains unclear. Therefore, there are no accurate diagnostic methods. Lipid metabolism is related to many immune related diseases, so this study set out to explore the relationship of lipids and IgAV and IgAVN.

Methods

Fifty-eighth patients with IgAV and 28 healthy controls were recruited, which were divided into six separate pools to investigate the alterations of serum lipids according to the clinical characteristics: healthy controls group (HCs) and IgAV group (IgAVs), IgAVN group (IgAV-N) and IgAV without nephritis group (IgAV-C), initial IgAV group (IgAV0) and IgAV in treatment with glucocorticoids group (IgAV1).

Results

31 identified lipid ions significantly changed in IgAVs with p < 0.05, variable importance of the projection (VIP) > 1 and fold change (FC) > 1.5. All these 31 lipid ions belong to 6 classes: triacylglycerols (TG), phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine, ceramide, and lysophosphatidylcholine. TG (16:0/18:1/22:6) +NH4 over 888875609.05, PC (32:1) +H over 905307459.90 and PE (21:4)-H less than 32236196.59 increased the risk of IgAV significantly (OR>1). PC (38:6) +H was significantly decreased (p < 0.05, VIP>1 and FC>1.5) in IgAVN. PC (38:6) less than 4469726623 conferred greater risks of IgAV (OR=45.833, 95%CI: 6.689~341.070).

Conclusion

We suggest that lipid metabolism may affect the pathogenesis of IgAV via cardiovascular disease, insulin resistance, cell apoptosis, and inflammation. The increase of TG(16:0/18:1/22:6) + NH4, and PC(32:1) + H as well as PE (21:4)-H allow a good prediction of IgAV. PE-to-PC conversion may participate in the damage of kidney in IgAV. PC (38:6) + H may be a potential biomarker for IgAVN.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-021-01185-1.

Clinical phenotype and cytokine profile of adult IgA vasculitis with joint involvement

OBJECTIVE

Joint involvement can be observed during the course of adult IgA vasculitis (IgAV). However, clinical picture, prognosis, or pathophysiological data associated with this condition have been overlooked. We aimed to describe the clinical characteristics and outcome of IgAV patients with joint involvement and look to a specific cytokine profile.

METHODS

We analyzed clinical and biological data from a nationwide study that included adult IgAV patients. Presentation and outcomes of patients with or without joint involvement were compared at baseline and during follow-up. Plasma cytokine measurements of IgAV patients included in a prospective study were also analyzed using multiplex assays.

RESULTS

Among 260 patients, 62% had joint involvement. Among them, rheumatological manifestations included arthralgia (100%) or arthritis (16%), mostly involving the knees and ankles. In multivariate analysis, patients with joint involvement, compared to those without, were younger (p = 0.002; OR 0.87; 95% CI 0.80-0.95) and showed more frequent gastrointestinal tract involvement (p = 0.012; OR = 2.08; 95% CI 1.18-3.67). However, no difference in terms of clinical response, relapse, end-stage renal disease, or death was observed between groups. Among 13 cytokines measured, plasma interleukin (IL)-1β level was higher in patients with joint involvement compared to those without (mean ± SEM IL-1β, 3.5 ± 1.2 vs. 0.47 ± 0.1 pg/ml; p = 0.024) or healthy controls (vs. 1.2 ± 0.5 pg/ml; p = 0.076).

CONCLUSION

Joint involvement is frequent in adult IgAV and is associated with more frequent gastrointestinal involvement. Increased plasma IL-1β levels raise the question of targeting this cytokine in patients with chronic and/or refractory joint involvement. Key Points • Joint involvement in adult IgAV is a frequent manifestation. • Joint involvement is associated with more frequent gastrointestinal manifestations. • Interleukin-1β (IL-1β) might orchestrate joint inflammation in adult IgAV. • IL-1β might be a therapeutic target in patients with chronic and/or refractory joint involvement.