CD151 Maintains Endolysosomal Protein Quality to Inhibit Vascular Inflammation.

BACKGROUND: Tetraspanin CD151 is highly expressed in endothelia and reinforces cell adhesion, but its role in vascular inflammation remains largely unknown. METHODS: In vitro molecular and cellular biological analyses on genetically modified endothelial cells, in vivo vascular biological analyses on genetically engineered mouse models, and in silico systems biology and bioinformatics analyses on CD151-related events. RESULTS: Endothelial ablation of Cd151 leads to pulmonary and cardiac inflammation, severe sepsis, and perilous COVID-19, and endothelial CD151 becomes downregulated in inflammation. Mechanistically, CD151 restrains endothelial release of proinflammatory molecules for less leukocyte infiltration. At the subcellular level, CD151 determines the integrity of multivesicular bodies/lysosomes and confines the production of exosomes that carry cytokines such as ANGPT2 (angiopoietin-2) and proteases such as cathepsin-D. At the molecular level, CD151 docks VCP (valosin-containing protein)/p97, which controls protein quality via mediating deubiquitination for proteolytic degradation, onto endolysosomes to facilitate VCP/p97 function. At the endolysosome membrane, CD151 links VCP/p97 to (1) IFITM3 (interferon-induced transmembrane protein 3), which regulates multivesicular body functions, to restrain IFITM3-mediated exosomal sorting, and (2) V-ATPase, which dictates endolysosome pH, to support functional assembly of V-ATPase. CONCLUSIONS: Distinct from its canonical function in strengthening cell adhesion at cell surface, CD151 maintains endolysosome function by sustaining VCP/p97-mediated protein unfolding and turnover. By supporting protein quality control and protein degradation, CD151 prevents proteins from (1) buildup in endolysosomes and (2) discharge through exosomes, to limit vascular inflammation. Also, our study conceptualizes that balance between degradation and discharge of proteins in endothelial cells determines vascular information. Thus, the IFITM3/V-ATPase-tetraspanin-VCP/p97 complexes on endolysosome, as a protein quality control and inflammation-inhibitory machinery, could be beneficial for therapeutic intervention against vascular inflammation.

Renal tubular estrogen ß receptors are expressed at high levels in small vessel vasculitis and are primarily localized in the distal tubule.

This study investigated the possible roles of renal estrogen receptors (ER) in glomerulonephritis associated with small vessel vasculitis. The relationships of ERs were investigated in antineutrophilic cytoplasmic antibody (ANCA)-associated glomerulonephritis and immunoglobulin A (IgA) nephropathy groups, which are small vessel vasculitis subtypes with two different glomerulonephritis development pathophysiologies. The design of this study was prepared as a retrospective cohort study. The study included 42 patients with ANCA-associated vasculitis and 18 with IgA nephropathy in the small vessel vasculitis group. For the control group, intact renal tissues of 28 patients who underwent nephrectomy due to renal cell carcinoma were used. Renal biopsy samples of the groups were stained with ER beta (ß) and ER alpha (α). Tubular ER ß expression score (TERßES) median values were found to be significantly higher in ANCA- associated vasculitis (B = 0.724, OR [95%CI]: 2.064 [1.141-3.731], p = .016) and IgA nephropathy (B = 0.898, OR [95%CI]: 2.454 [1.307-4.609], p = .005) than in intact kidney tissue. It was determined that tubular ERß was most frequently localized in the distal tubule at 57.9% and the second most common in the proximal tubule at 20.4%. The expression of tubular ERß is increased in glomerulonephritis due to small vessel vasculitis. Tubular ERßs are most commonly localized in the distal tubule. Further studies are needed to understand the physiological and pathophysiological effects of altered renal ER levels in small vessel vasculitis.

Inhibition of IL-1 Ameliorates Cardiac Dysfunction and Arrhythmias in a Murine Model of Kawasaki Disease.

BACKGROUND: Kawasaki disease (KD) is an acute febrile illness and systemic vasculitis often associated with cardiac sequelae, including arrhythmias. Abundant evidence indicates a central role for IL (interleukin)-1 and TNFα (tumor necrosis factor-alpha) signaling in the formation of arterial lesions in KD. We aimed to investigate the mechanisms underlying the development of electrophysiological abnormalities in a murine model of KD vasculitis. METHODS: Lactobacillus casei cell wall extract-induced KD vasculitis model was used to investigate the therapeutic efficacy of clinically relevant IL-1Ra (IL-1 receptor antagonist) and TNFα neutralization. Echocardiography, in vivo electrophysiology, whole-heart optical mapping, and imaging were performed. RESULTS: KD vasculitis was associated with impaired ejection fraction, increased ventricular tachycardia, prolonged repolarization, and slowed conduction velocity. Since our transcriptomic analysis of human patients showed elevated levels of both IL-1ß and TNFα, we asked whether either cytokine was linked to the development of myocardial dysfunction. Remarkably, only inhibition of IL-1 signaling by IL-1Ra but not TNFα neutralization was able to prevent changes in ejection fraction and arrhythmias, whereas both IL-1Ra and TNFα neutralization significantly improved vasculitis and heart vessel inflammation. The treatment of L casei cell wall extract-injected mice with IL-1Ra also restored conduction velocity and improved the organization of Cx43 (connexin 43) at the intercalated disk. In contrast, in mice with gain of function of the IL-1 signaling pathway, L casei cell wall extract induced spontaneous ventricular tachycardia and premature deaths. CONCLUSIONS: Our results characterize the electrophysiological abnormalities associated with L casei cell wall extract-induced KD and show that IL-1Ra is more effective in preventing KD-induced myocardial dysfunction and arrhythmias than anti-TNFα therapy. These findings support the advancement of clinical trials using IL-1Ra in patients with KD.

Porto-sinusoidal vascular disorder and nephrotic-range proteinuria due to venous vasculitis in Behçet's disease.

Behçet's disease (BD) is an autoinflammatory disease with multifactorial and polygenic etiology, potentially involving arteries and veins of any size resulting in variable vessel vasculitis. We report a case of an Iranian male who presented with porto-sinusoidal vascular disorder due to venous vasculitis as initial manifestation of BD. Despite immunosuppression, anticoagulation and venous recanalization, he subsequently developed severe nephrotic-range proteinuria mimicking a primary renal disease which was completely and immediately ameliorated by stenting of the vena cava. This demonstrates that the proteinuria was caused by increased intraglomerular pressure due to venous outflow obstruction as a consequence of venous vasculitis. To our knowledge, this is the first report of massive proteinuria caused by venous obstruction of the caval vein in the context of BD. Altogether, this case demonstrates the extensive spectrum of vascular disease in BD.

Cryoglobulinemic vasculitis: a 2023 update.

PURPOSE OF REVIEW: Cryoglobulinemic vasculitis (CV) is an immune complex mediated small vessel vasculitis characterized by the presence of cryoglobulins in serum, often associated with hepatitis C infection, systemic autoimmune diseases or hematological conditions. The focus of this review is to provide an update on new insights into pathogenesis, epidemiology and therapies of infectious and noninfectious type II and type III CV. RECENT FINDINGS: The introduction of new antiviral drugs for treatment of hepatitis C infection implied major changes in HCV-related CV, allowing to shed new lights on CV pathogenesis and mechanisms of relapse and, therefore, to increase the relevance of autoimmune diseases in CV epidemiology. Specific B-cell clones are involved in the production of pathogenic immune complexes that leads to small-vessel vasculitis. Therefore, both antiviral treatments [direct-acting antivirals (DAAs) and oral nucleot(s)ide analogues] and targeted anti-CD20 therapies (rituximab) prove to be safe and effective options, leading to a better prognosis. Association of Sjögren syndrome and CV defines a specific phenotype of patients, characterized by severe manifestations and poor outcome. SUMMARY: Removing viral stimulation on B-cells through direct-acting antivirals and blocking B-cells proliferation and differentiation with rituximab are the goals of treatment of CV. However, further research is needed to identify prognostic factors of refractory and relapsing disease.

Renal disease in pediatric rheumatology.

PURPOSE OF REVIEW: This review will provide updates in the outcomes in the common rheumatologic diseases with kidney involvement. Covered are also advances in therapeutics for the use of pediatric rheumatologic diseases with kidney involvement, as well as the potential kidney complications from other rheumatologic diseases and their medications. RECENT FINDINGS: Two of the more common rheumatologic diseases with kidney involvement, lupus and vasculitis, continue to show inadequate response to initial therapy of renal disease and practice continues to be driven by results of adult studies. SUMMARY: There is a continued need for pediatric specific studies in rheumatologic diseases with kidney involvement as outcomes continue to be inadequate. Despite recently approved treatments for adults with rheumatic diseases and kidney involvement, therapeutic options in pediatrics remain limited, contributing to the overall morbidity and mortality.

Vasculitis and the NLRP3 inflammasome.

PURPOSE OF REVIEW: Vasculitis are a group of heterogeneous conditions characterized by chronic inflammation of blood vessels, leading to tissue destruction and organ failure. Vasculitis is an inflammatory process in which immune effector cells infiltrate blood vessels and surrounding tissues. The involvement of inflammasomes seems to occur during inflammatory processes. RECENT FINDINGS: Studies have emphasized that genetic susceptibility is an important aspect of the pathogenesis of vasculitis. The innate immune system is a major contributor to these inflammatory diseases, suggesting that the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome plays a key role. NLRP3 activation causes the assembly of a large multiprotein and leads to the secretion of bioactive interleukin (IL)-1ß and IL-18 as well as the induction of inflammatory cell death, termed pyroptosis. Accumulating evidence confirms the involvement of this cascade in sterile inflammatory diseases and other vascular diseases. SUMMARY: In this review, we will summarize the current state of knowledge regarding the role of NLRP3 inflammasome in vascular diseases, and discuss the potential of the NLRP3 inflammasome as a therapeutic target.

Unmet need in rheumatology: reports from the Advances in Targeted Therapies meeting, 2023.

The Advances in Targeted Therapies meets annually, convening experts in the field of rheumatology to both provide scientific updates and identify existing scientific gaps within the field. To review the major unmet scientific needs in rheumatology. The 23rd annual Advances in Targeted Therapies meeting convened with more than 100 international basic scientists and clinical researchers in rheumatology, immunology, infectious diseases, epidemiology, molecular biology and other specialties relating to all aspects of immune-mediated inflammatory diseases. We held breakout sessions in five rheumatological disease-specific groups including: rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthritis (axSpa), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and vasculitis, and osteoarthritis (OA). In each group, experts were asked to identify and prioritise current unmet needs in clinical and translational research. An overarching theme across all disease states is the continued need for clinical trial design innovation with regard to therapeutics, endpoint and disease endotypes. Within RA, unmet needs comprise molecular classification of disease pathogenesis and activity, pre-/early RA strategies, more refined pain profiling and innovative trials designs to deliver on precision medicine. Continued scientific questions within PsA include evaluating the genetic, immunophenotypic, clinical signatures that predict development of PsA in patients with psoriasis, and the evaluation of combination therapies for difficult-to-treat disease. For axSpA, there continues to be the need to understand the role of interleukin-23 (IL-23) in pathogenesis and the genetic relationship of the IL-23-receptor polymorphism with other related systemic inflammatory diseases (eg, inflammatory bowel disease). A major unmet need in the OA field remains the need to develop the ability to reliably phenotype and stratify patients for inclusion in clinical trials. SLE experts identified a number of unmet needs within clinical trial design including the need for allowing endpoints that reflect pharmacodynamic/functional outcomes (eg, inhibition of type I interferon pathway activation; changes in urine biomarkers). Lastly, within SSc and vasculitis, there is a lack of biomarkers that predict response or disease progression, and that allow patients to be stratified for therapies. There remains a strong need to innovate clinical trial design, to identify systemic and tissue-level biomarkers that predict progression or response to therapy, endotype disease, and to continue developing therapies and therapeutic strategies for those with treatment-refractory disease. This document, based on expert consensus, should provide a roadmap for prioritising scientific endeavour in the field of rheumatology.

Outcome and prognosis of isolated carotid vasculitis.

OBJECTIVE: To assess the prognosis and outcome of patients with isolated carotid vasculitis. METHODS: We performed a retrospective multicenter study of 36 patients (median age at diagnosis was 37 [IQR 27-45] years and 11 [31 %] patients were men) with initial presentation as isolated carotid vasculitis. Study endpoints included vascular complications, relapses, and progression to large vessel vasculitis (i.e. Giant cell arteritis or Takayasu). RESULTS: The most frequent involvement was the left internal carotid artery (39 %), and 81 % had stenosis. After a median follow-up of 32 months [IQR 12-96], 21 (58 %) patients had a vascular event, including 31 % of new onset vascular lesions and 25 % of stroke/transient ischemic attack. Patients with stroke had less carotidynia at diagnosis (33 % vs 74 %, p = 0.046), higher significant carotid stenosis (i.e. > 50 %) (89 % vs. 30 %, p = 0.026) and higher severe carotid stenosis (i.e. >70 %) (67 % vs 19 %, p = 0.012), compared to those without stroke. Twenty (52 %) patients experienced relapses. High CRP at diagnosis was associated with relapses (p = 0.022). At the end of follow-up, 21 (58 %) patients were classified as having Takayasu arteritis, 13 (36 %) as isolated carotid vasculitis, and two (6 %) as giant cell arteritis. CONCLUSION: Carotid vasculitis may occur as a topographically limited lesion and is associated with significant rate of vascular complications.

Automated whole slide morphometry of sural nerve biopsy using machine learning.

AIM: The morphometry of sural nerve biopsies, such as fibre diameter and myelin thickness, helps us understand the underlying mechanism of peripheral neuropathies. However, in current clinical practice, only a portion of the specimen is measured manually because of its labour-intensive nature. In this study, we aimed to develop a machine learning-based application that inputs a whole slide image (WSI) of the biopsied sural nerve and automatically performs morphometric analyses. METHODS: Our application consists of three supervised learning models: (1) nerve fascicle instance segmentation, (2) myelinated fibre detection and (3) myelin sheath segmentation. We fine-tuned these models using 86 toluidine blue-stained slides from various neuropathies and developed an open-source Python library. RESULTS: Performance evaluation showed (1) a mask average precision (AP) of 0.861 for fascicle segmentation, (2) box AP of 0.711 for fibre detection and (3) a mean intersection over union (mIoU) of 0.817 for myelin segmentation. Our software identified 323,298 nerve fibres and 782 fascicles in 70 WSIs. Small and large fibre populations were objectively determined based on clustering analysis. The demyelination group had large fibres with thinner myelin sheaths and higher g-ratios than the vasculitis group. The slope of the regression line from the scatter plots of the diameters and g-ratios was higher in the demyelination group than in the vasculitis group. CONCLUSION: We developed an application that performs whole slide morphometry of human biopsy samples. Our open-source software can be used by clinicians and pathologists without specific machine learning skills, which we expect will facilitate data-driven analysis of sural nerve biopsies for a more detailed understanding of these diseases.

A specific diagnostic metabolome signature in adult IgA vasculitis.

INTRODUCTION: IgA vasculitis diagnosis relies primarily on clinical features and is confirmed by pathological findings. To date, there is no reliable noninvasive diagnostic biomarker. OBJECTIVE: We aimed to explore the baseline serum metabolome of adult patients with IgA vasculitis to identify potential diagnostic biomarkers. METHODS: We performed a study comparing the serum metabolome of patients with IgA vasculitis to that of patients with inflammatory condition, namely spondyloarthritis. Serum analyses were performed by high-performance liquid chromatography-mass spectrometry. RESULTS: Fifty-five patients with IgA vasculitis and 77 controls with spondyloarthritis (age- and sex-matched) were included in this study. The median age of IgA vasculitis patients was 53 years. Two-thirds of patients were female (n = 32). At the time of vasculitis diagnosis, 100% of patients had skin involvement and 69% presented with glomerulonephritis (n = 38). Joint and digestive involvement were observed in 56% (n = 31) and 42% (n = 23) of patients. Four discriminative metabolites between the two groups were identified: 1-methyladenosine, L-glutamic acid, serotonin, and thymidine. The multivariate model built from the serum metabolomes of patients with IgA vasculitis and spondyloarthritis revealed an accuracy > 90%. As this model was significant according to the permutation test (p < 0.01), independent validation showed an excellent predictive value of the test set: sensitivity 98%; specificity 98%, positive predictive value 97% and negative predictive value 98%. CONCLUSION: To our knowledge, this study is the first to use the metabolomic approach for diagnostic purposes in adult IgA vasculitis, highlighting a specific diagnostic metabolome signature.

Scleritis and Development of Immune-Mediated Disease: A Retrospective Chart Review.

OBJECTIVE: Scleritis may be idiopathic or caused by trauma, infections, or an immune-mediated disease (IMD). Our study aimed to understand the relationship between scleritis and IMD, including presenting characteristics, serologies, and treatment course. Understanding these associations may allow clinicians to risk-stratify patients and predict their clinical and treatment course. METHODS: We conducted a retrospective chart review of 341 patients with scleritis seen at a tertiary care center between January 1, 2005, and December 31, 2020. Demographics, scleritis characteristics, treatment response, recurrence, and serologic data were compared among patients with idiopathic and IMD-associated scleritis. RESULTS: Among patients with scleritis seen, 145 patients (43%) had an associated IMD, most commonly rheumatoid arthritis (RA; 39%), vasculitis (21%), or inflammatory bowel disease (14%). In most cases, the IMD diagnosis predated the scleritis presentation (63%), though vasculitis cases were more likely to develop during or after scleritis episodes. There were no significant differences in demographics or treatment failures among patients with scleritis with and without associated IMDs. Patients with IMDs were more likely to have a recurrence of scleritis (62% vs 49%, P = 0.02). CONCLUSION: At our ophthalmology center, 43% of patients with scleritis had an associated IMD, and most patients with an IMD were symptomatic from this disease prior to scleritis presentation. RA was the most commonly associated condition and typically predated the scleritis, whereas vasculitis was more likely diagnosed during or after the scleritis episode. Scleritis among patients with IMD is more likely to recur compared to scleritis that is idiopathic.

Long-term clinical and ultrasound follow-up after transient perivascular inflammation of the carotid artery (TIPIC) syndrome: a multicenter study.

BACKGROUND: The present study aimed to describe the clinical and ultrasound (US) long-term follow-up of patients with transient perivascular inflammation of the carotid artery (TIPIC) syndrome and the risk of recurrence. METHODS: We enrolled patients with a definitive diagnosis of TIPIC syndrome who were included in a retrospective multicenter study. These patients were recontacted at least six months after the first TIPIC episode for a clinical and imaging follow-up. Each patient underwent a clinical evaluation through a tailored questionnaire as well as US imaging. RESULTS: Twenty-eight patients were enrolled with a median follow-up of 58.7 months (interquartile range = 8-121). Nineteen out of the 28 patients (67.8%) had residual pain, eight (28.6%) had experienced a clinical recurrence and 12 (42.9%) had a thickening of the carotid wall on US. No patients had neurological complication or other associated diseases. CONCLUSIONS: Patients with TIPIC syndrome have often residual pain and recurrence in about one quarter of cases but the long-term follow-up is in favor a benign self-limited pathology.Trial registration: ClinicalTrials.gov (identifier NCT03804112).

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

BACKGROUND: Antineutrophil cytoplasmatic antibodies (ANCA) have been detected in patients with systemic lupus erythematosus (SLE). In this study, we investigated the presence of ANCA in a sample of Brazilian SLE patients and its possible associations with clinical and serological outcomes. Additionally, we reviewed the literature of on ANCA in SLE. RESULTS: The presence of ANCA was detected in 130 patients using indirect immunofluorescence (IIF). The test was positive in 29.9% of the cases (17.6% pANCA and 11.5% cANCA). Male sex and peripheral vasculitis were more prevalent in the ANCA-positive sample. cANCA was associated with lupus anticoagulant and pANCA had a positive association with peripheral vasculitis and a negative association with anti- SSB/La antibodies. In the 22 studies included in the literature review, a wide range of ANCA positivity was found (13% to 81.1% by IIF and 0 to 22.2% by ELISA). ANCA was associated with renal damage in the Asian population. Although other associations have been found in isolated studies, they were not consistently reported. CONCLUSIONS: The ANCA prevalence found in this Brazilian sample was within the range reported in the literature and these autoantibodies were more frequent in males and in patients with vasculitis. The literature showed controversial results on the association between ANCA and SLE disease activity or clinical characteristics.

Navigating the diagnostic maze: A case presentation of C1q vasculitis mimicking hypocomplementemic urticarial vasculitis in a patient with systemic lupus erythematosus.

In rare instances, patients with SLE may exhibit atypical clinical manifestations, such as Hypocomplementemic Urticarial Vasculitis, which can pose diagnostic challenges. Here, we present a case report of a 28-year-old female with a history of SLE with lupus nephritis clase IV who developed HUV-like symptoms, ultimately leading to a diagnosis of C1q Vasculitis. This case underscores the importance of considering C1q Vasculitis in SLE patients presenting with HUV-like features and highlights Rituximab as a promising therapeutic option for managing this rare condition.

Outcome of immunosuppression in children with IgA vasculitis-related nephritis.

BACKGROUND: Immunoglobulin A vasculitis with nephritis (IgAVN) is the most common vasculitis in children. Due to a lack of evidence, treatment recommendations are based on expert opinion, resulting in variation. The aim of this study was to describe the clinical presentation, treatment and outcome of an extremely large cohort of children with biopsy-proven IgAVN in order to identify prognostic risk factors and signals of treatment efficacy. METHODS: Retrospective data were collected on 1148 children with biopsy-proven IgAVN between 2005 and 2019 from 41 international paediatric nephrology centres across 25 countries and analysed using multivariate analysis. The primary outcome was estimated glomerular filtration rate (eGFR) and persistent proteinuria at last follow-up. RESULTS: The median follow-up was 3.7 years (interquartile range 2-6.2). At last follow-up, 29% of patients had an eGFR <90 mL/min/1.73 m2, 36% had proteinuria and 3% had chronic kidney disease stage 4-5. Older age, lower eGFR at onset, hypertension and histological features of tubular atrophy and segmental sclerosis were predictors of poor outcome. There was no evidence to support any specific second-line immunosuppressive regimen being superior to others, even when further analysing subgroups of children with reduced kidney function, nephrotic syndrome or hypoalbuminemia at onset. Delayed start of immunosuppressive treatment was associated with a lower eGFR at last follow-up. CONCLUSION: In this large retrospective cohort, key features associated with disease outcome are highlighted. Importantly, there was no evidence to support that any specific immunosuppressive treatments were superior to others. Further discovery science and well-conducted clinical trials are needed to define accurate treatment and improve outcomes of IgAVN.

Granuloma, vasculitis, and demyelination in sarcoid neuropathy.

BACKGROUND: Despite the suggestion that direct compression by granuloma and ischemia resulting from vasculitis can cause nerve fiber damage, the mechanisms underlying sarcoid neuropathy have not yet been fully clarified. METHODS: We examined the clinicopathological features of sarcoid neuropathy by focusing on electrophysiological and histopathological findings of sural nerve biopsy specimens. We included 18 patients with sarcoid neuropathy who had non-caseating epithelioid cell granuloma in their sural nerve biopsy specimens. RESULTS: Although electrophysiological findings suggestive of axonal neuropathy were observed, particularly in the lower limbs, all but three patients showed ≥1 abnormalities in nerve conduction velocity or distal motor latency. Additionally, a conduction block was observed in 11 of the 16 patients for whom waveforms were assessed; five of them fulfilled motor nerve conduction criteria strongly supportive of demyelination as defined in the European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) guideline for chronic inflammatory demyelinating polyneuropathy (CIDP). In most patients, sural nerve biopsy specimens revealed a mild to moderate degree of myelinated fiber loss. Fibrinoid necrosis was observed in one patient, and electron microscopy analysis revealed demyelinated axons close to granulomas in six patients. CONCLUSIONS: Patients with sarcoid neuropathy may meet the EAN/PNS electrophysiological criteria for CIDP due to the frequent presence of conduction blocks. Based on our results, in addition to the ischemic damage resulting from granulomatous inflammation, demyelination may play an important role in the mechanism underlying sarcoid neuropathy.

Post COVID-19 vaccination medium vessel vasculitis: a systematic review of case reports.

PURPOSE: Vaccinations are essential in minimizing the effects of global health crises including COVID-19 pandemic. This study investigates the potential association between COVID-19 vaccination and the occurrence of medium vessel vasculitis. METHODS: Several databases were utilized to conduct a comprehensive literature review. The studies were carefully evaluated to ensure their quality and eliminate any potential bias. RESULTS: After reviewing 935 search results and removing duplicates, we selected 10 case reports. We discovered that medium vessel vasculitis may occur after COVID-19 vaccination, typically appearing around 16.2 days after vaccination. The patients in the study had a median age of 43.5 years and were predominantly males (80%). Additionally, half of the cases were reported after the second dose of vaccination. CONCLUSIONS: Vaccination-associated vasculitis is a rare yet possible complication of COVID-19 vaccination and lacks a clear treatment protocol.

A Review of IgA Vasculitis (Henoch-Schönlein Purpura) Past, Present, and Future.

The clinical association of purpura, arthralgia, and arthritis was first described in 1837 in a publication by Johann Lukas Schönlein, a German physician. In 1874, Eduard Henoch, a student of Schönlein, reported cases of children with purpura, abdominal pain, bloody diarrhea, and joint pain. IgA vasculitis, or Henoch-Schönlein purpura, is a systemic hypersensitivity vasculitis caused by the deposition of immune complexes in small blood vessels, including the renal glomeruli and mesangium. In the skin, the presentation is with non-thrombocytopenic purpura or urticaria. Worldwide, IgA nephropathy is the most common cause of primary glomerulonephritis. Detection of IgA deposition in small blood vessels and the renal glomeruli is diagnostic in most cases. This article aims to review the history, current classification, epidemiology, presentation, and diagnosis of IgA vasculitis and nephropathy, disease associations or trigger factors, including infections, vaccines, and therapeutic agents, and highlights some future approaches to improve diagnosis and clinical management.

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.