Clinical characteristics and risk factors of cardiac involvement in pediatric immunoglobulin A vasculitis: A 7-year retrospective study from a single tertiary medical center.

Immunoglobulin A vasculitis(IgAV) is the most common form of systemic vasculitis affecting children. To date, cardiac involvement in pediatric IgAV has not been fully investigated and its prevalence may be underestimated. This study aims to reveal the clinical and laboratory characteristics of cardiac involvement in pediatric IgAV and further determine its risk factors. A total of 1451 children with IgAV were recruited between January 2016 and December 2022. According to the severity of cardiac involvement, the patients were divided into the myocarditis/suspected myocarditis group, cardiac abnormalities group, and non-cardiac involvement group. Demographic, clinical, and laboratory characteristics were retrospectively extracted from the individual data collected in the medical records. Among the 1451 pediatric IgAV patients, 179 (12.3%) were identified with cardiac involvement, including 154 (10.6%) with cardiac abnormalities and 25 (1.7%) with myocarditis/suspected myocarditis. Cardiac involvement in pediatric IgAV mainly manifested as elevated cardiac biomarker levels (n = 162), electrocardiogram abnormalities (n = 46), and echocardiogram/chest X-ray abnormalities (n = 15); however, cardiac-related symptoms were only observed in 15.1% of patients with cardiac involvement. Multivariate analysis demonstrated that interval from disease onset to diagnosis > 7 days (OR, 2.157; 95% CI, 1.523-3.057; p < 0.001), IgAV with multi-organ involvement (OR, 1.806; 95% CI, 1.242-2.627; p = 0.002), and elevated D-dimer levels (OR, 1.939; 95% CI, 1.259-2.985; p < 0.001) were independent risk factors for cardiac involvement in pediatric IgAV. The length of hospital stay was significantly longer in the myocarditis/suspected myocarditis group compared with the other two groups (p < 0.05).     Conclusion: This study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV. What is Known: • Immunoglobulin A vasculitis (IgAV) is the most common form of systemic vasculitis affecting children and adolescents, which exhibits diverse clinical manifestations. Cases of severe IgAV complicated by cardiac involvement have been anecdotally reported. What is New: • The present study suggests that cardiac involvements in pediatric IgAV is non-negligible, and cardiac involvement is associated with interval from disease onset to diagnosis > 7 days, IgAV with multi-organ involvement, and elevated D-dimer levels. Severe cardiac involvement may affect the prognosis of pediatric IgAV.

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.

[Urinary protein and renal pathological features in children with immunoglobulin A vasculitis with nephritis and hypercoagulability]. / 儿童IgAè¡€ç®¡ç‚Žè‚¾ç‚Žä¼´é«˜å‡çŠ¶æ€çš„å°¿è›‹ç™½å’Œè‚¾è„ç— ç†ç‰¹å¾åˆ†æž.

OBJECTIVES: To study the association of hypercoagulability with urinary protein and renal pathological damage in children with immunoglobulin A vasculitis with nephritis (IgAVN). METHODS: Based on the results of coagulation function, 349 children with IgAVN were divided into a hypercoagulability group consisting of 52 children and a non-hypercoagulability group consisting of 297 children. Urinary protein and renal pathological features were compared between the two groups, and the factors influencing the formation of hypercoagulability in children with IgAVN were analyzed. RESULTS: Compared with the non-hypercoagulability group, the hypercoagulability group had significantly higher levels of urinary erythrocyte count, 24-hour urinary protein, urinary protein/creatinine, urinary immunoglobulin G/creatinine, and urinary N-acetyl-ß-D-glucosaminidase (P<0.05). The hypercoagulability group also had a significantly higher proportion of children with a renal pathological grade of III-IV, diffuse mesangial proliferation, capillary endothelial cell proliferation, or >25% crescent formation (P<0.05). The multivariate logistic regression analysis showed that capillary endothelial cell proliferation and glomerular crescent formation >25% were associated with the formation of hypercoagulability in children with IgAVN (P<0.05). CONCLUSIONS: The renal injury in IgAVN children with hypercoagulability is more severe, with greater than 25% crescent formation and increased proliferation of glomerular endothelial cells being important contributing factors that exacerbate the hypercoagulable state in IgAVN.

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.

Intussusception as a rare manifestation of immunoglobulin A vasculitis: Risk factors and treatment.

AIM: To identify the risk factors associated with intussusception in children with immunoglobulin A vasculitis (IgAV)-gastrointestinal (GI) tract involvement and to evaluate the outcomes of medical treatment and surgical intervention and the course of patients with intussusception. METHODS: This retrospective study was conducted in 157 patients under 18 years of age who were followed up with the diagnosis of IgAV-GI tract involvement between January 2015 and September 2022. The characteristics of the patients who developed intussusception were evaluated in detail. RESULTS: One hundred and fifty-seven patients with GI tract involvement were included in the study. The mean age of patients with IgAV-GI tract involvement was 8.7 ± 3.7 years. The female-to-male ratio was 1:1.5. Intussusception was detected in 14 patients (8.9%). Two patients (14.3%) underwent surgery, and the remaining 12 patients (85.7%) had their medical therapy intensified. Patients with GI tract involvement were divided into two groups as with (n = 14) and without (n = 143) intussusception. There was a statistically significant difference between the groups in the time from the onset of the first symptom of IgAV to the onset of steroids (P = 0.001). There were no statistically significant differences between the groups in age at onset of IgAV, gender distribution, erythrocyte sedimentation rate and C-reactive protein levels. CONCLUSIONS: The time from the onset of the first symptom of IgAV to the start of steroids is a risk factor for the development of intussusception in patients with IgAV-GI tract involvement. In these patients, medical treatment usually reduces intussusception without the need for surgical intervention.

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.

[Research advances in the etiology and pathogenesis of immunoglobulin A vasculitis]. / å ç–«çƒè›‹ç™½Aè¡€ç®¡ç‚Žç— å› åŠå‘ç— æœºåˆ¶çš„ç ”ç©¶è¿›å±•.

Immunoglobulin A vasculitis (IgAV), also known as Henoch-Schönlein purpura, has complex etiology and pathogenesis which have not been fully clarified. The latest research shows that SARS-CoV-2 and related vaccines, human papilloma vaccine, and certain biological agents can also induce IgAV. Most studies believe that the formation of galactose-deficient IgA1 (Gd-IgA1) and Gd-IgA1-containing immune complex plays a crucial role in the pathogenesis of IgAV. It is hypothesized that the pathogenesis of IgAV is associated with the binding of IgA1 to anti-endothelial cell antibodies. In addition, genetics also constitutes a major focus of IgAV research. This article reviews the new advances in the etiology of IgAV and summarizes the role of Gd-IgA1, Gd-IgA1-containing immune complex, anti-endothelial antibody, IgA1 conjugates, T lymphocyte immunity, and genetic factors in the pathogenesis of IgAV.

Coronavirus disease 2019, vaccination against coronavirus and immunoglobulin A-mediated diseases: systematic literature review.

Coronavirus disease 2019 (COVID-19) and vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been associated with autoimmune phenomena. However, the interplay between COVID-19 or vaccination against SARS-CoV-2 and Berger glomerulonephritis or Henoch-Schönlein vasculitis, two diseases mediated by immunoglobulin A, has never been comprehensively investigated. Therefore, we carried out a systematic review of the literature on this topic. Following databases were used: Google Scholar, Excerpta Medica and the United States National Library of Medicine. Eighty-seven patients with immunoglobulin A-mediated diseases associated with SARS-CoV-2 infection or vaccination against coronavirus were sorted out (53% males, 47% females; 34 17-51 years of age, median and interquartile range): 47 cases of Berger glomerulonephritis and 40 of Henoch-Schönlein vasculitis. Approximately 50% (N = 24) of Berger glomerulonephritis and 10% (N = 4) of Henoch-Schönlein vasculitis patients presented with a pre-existing history of immunoglobulin A-mediated disease. Almost all cases of Berger glomerulonephritis were vaccine-associated (N = 44; 94%), while most cases of Henoch-Schönlein vasculitis were infection-associated (N = 23; 57%). Among vaccine-associated immunoglobulin A diseases, about 90% were associated to mRNA-based vaccines. Our analysis supports the hypothesis that COVID-19 and vaccination against SARS-CoV-2 may trigger or exacerbate an immunoglobulin A-mediated diseases.

Predicting Severe Renal and Gastrointestinal Involvement in Childhood Immunoglobulin A Vasculitis with Routine Laboratory Parameters.

BACKGROUND: Immunoglobulin A vasculitis (IgAV) is the most common vasculitis in children. Although childhood IgAV is generally considered as a self-limited disease, progressive course and poor prognosis could occur in some cases which mostly result from severe renal involvement and gastrointestinal (GI) involvement. METHODS: We performed a retrospective study of pediatric patients diagnosed as IgAV in our institution from 2016 to 2019. Patients were divided into groups based on the occurrence and severity of GI and renal involvement. Analysis of variance (ANOVA) and Kruskal-Wallis test were used to compare results of laboratory parameters among groups and prediction models were built by using logistic regression analysis. RESULTS: A total of 286 patients were enrolled. GI involvement occurred in 148 (51.7%) patients, 30 (20.3%) of which were severe cases. Renal involvement developed in 120 (42.0%) patients, 22 (18.3%) of which were severe cases. Compared with patients with only cutaneous manifestations, white blood cell (WBC) count, neutrophil-to-lymphocyte ratio (NLR), and D-dimer levels were higher in those with GI involvement, and D-dimer level was found to be positively associated with severity. Increased NLR and lower complement 3 (C3) were found in patients with renal involvement, but only C3 was relevant in distinguishing moderate and severe cases. The prediction model for severe renal involvement was: Logit (P) = 6.820 + 0.270 (age) + 0.508 (NLR) - 16.130 (C3), with an AUC of 0.914. The prediction model for severe GI involvement was: Logit (P) = -5.459 + 0.005 (WBC) + 1.355 (D-dimer) - 0.020 (NLR), with an AUC of 0.849. CONCLUSION: Our data suggest C3 to be an exclusive predictor for severe renal involvement and D-dimer level to be positively associated with the severity of GI involvement. Prediction models consisting of the above parameters were built for obtaining prognostic information in the early phase of IgAV.

Genome-wide association study of 7661 Chinese Han individuals and fine-mapping major histocompatibility complex identifies HLA-DRB1 as associated with IgA vasculitis.

BACKGROUND: Immunoglobulin-A vasculitis (IgAV) is an immune-related systemic vasculitis with an unclear etiology. Genetic predisposition is now considered to be closely associated with the development of the disease, and it is essential to reveal the relationship between them. To explore the role of heredity in the disease, we performed a genome-wide association study (GWAS) of 496 IgAV cases and 7165 controls using an Illumina Infinium Global Screening Array chip. METHODS: In the first stage of analysis, a significant correlation between the major histocompatibility complex (MHC) and IgAV was observed. Subsequently, human leukocyte antigen (HLA) analysis was conducted using a new large-scale Han-MHC reference panel. Fine mapping of IgAV risk in the MHC region indicated that two amino acid positions, 120 and 11, of HLA-DRB1 and three potential HLA alleles (HLA-DRB1∗04, HLA-DRB1∗16, and HLA-DRB1∗16:02) were significantly associated. RESULTS: Further stepwise conditional analysis demonstrated that 3 amino acid positions (120, 26, 96) of HLA-DRB1 and 6 HLA-DRB1 alleles (HLA-DRB1*04, HLA-DRB1*16, HLA-DRB1*01, HLA-DRB1*12:02, HLA-DRB1*10, and HLA-DRB1*15:02) were independent signals. Among them, the most significant signal was HLA-DRB1 amino acid Ser120 (OR = 1.59, p = 3.19 × 10-8 ); no independent signal in the MHC region except for HLA-DRB1 was found. CONCLUSIONS: Our study confirms that the pathogenesis of IgAV has a genetic component and that HLA-DRB1 is strongly associated with susceptibility to IgAV.

[Primary vasculitides in childhood and adulthood]. / Primäre Vaskulitiden im Kindes- und Erwachsenenalter.

Primary systemic vasculitides can be observed at any age. Some vasculitides occur preferentially in childhood, such as Kawasaki syndrome or immunoglobulin A (IgA) vasculitis, whereas others, such as giant cell arteritis, occur beyond the age of 50 years. Vasculitides occurring in childhood or adolescence and adulthood may have different phenotypes, different disease courses and outcomes depending on the age of manifestation. For example, those with Takayasu arteritis beginning in adolescence have different vascular involvement, a higher degree of systemic inflammation and a more aggressive course of disease than those with adult-onset disease. In contrast, IgA vasculitis is more severe in adults than in children. The causes for the age predilections and different age-dependent disease manifestations have not yet been clarified. The therapeutic principles are similar for vasculitides occurring in children or adolescents and adults. The first international evidence-based treatment recommendations are now available for juvenile vasculitides, although the evidence for certain forms of treatment is still very limited. The treatment of adult vasculitides can be guided by numerous national and international guidelines and recommendations. Many vasculitides carry a high risk of morbidity and mortality and the timely detection and treatment are therefore necessary. In this article, similarities and differences in the clinical presentations, treatment, courses and prognosis of vasculitides in children or adolescents and adults are discussed.

Deficiency in the frequency and function of Tr1 cells in IgAV and the possible role of IL-27.

OBJECTIVE: Type 1 regulatory T (Tr1) cells are involved in the pathogenesis of numerous immune-mediated diseases. However, little is known about whether and how Tr1 cells affect the development of IgA vasculitis (IgAV). We aimed to investigate this question in IgAV patients. METHODS: . Tr1 cells in peripheral blood and kidney tissue of IgAV patients were analysed by multi-parametric flow cytometry and immunofluorescence techniques. An in vitro assay of suppression of T cell proliferation and cytokine release was performed to evaluate the function of Tr1 cells. Real-time PCR and cell stimulation in vitro were used to explore the roles of IL-27 and early growth response gene 2 (EGR2). RESULTS: The frequency of Tr1 cells was decreased in peripheral blood but increased in kidney tissue from IgAV patients. A defective suppressive function of Tr1 cells in IgAV was observed. The frequency of Tr1 cells and the cytokines secreted by them were up-regulated in the presence of recombinant IL-27 in vitro. Moreover, IL-27 also increased the expression of EGR2. Furthermore, lower frequency of Tr1 cells during remission had a higher recurrence rate. CONCLUSION: Tr1 cells are involved in the pathogenesis of IgAV. The low IL-27 in IgAV is responsible for impaired frequency and function of Tr1 cells, and EGR2 may be the specific transcription factor involved in the progression. Tr1 may be a risk factor for IgAV recurrence.

Biopsy-proven Henoch-Schönlein purpura nephritis: a single center experience.

BACKGROUND: Knowledge on normal progress and treatment of Henoch-Schönlein purpura nephritis (HSPN) is limited. This study reviews outcome, clinical, pathological, and therapeutic factors affecting the prognosis of HSPN patients. METHODS: Forty-nine children with biopsy-confirmed HSPN diagnosed between September 2008 and 2018 were included. Demographics, clinical and laboratory data, treatment, and outcome were recorded at the time of biopsy, 3, 6, 12, and 24 months and at last visit. Clinical outcome was graded according to Meadow's criteria. RESULTS: The median age at time of biopsy was 10.1 years (IQR:5.7) and female/male ratio 24/25. At presentation, 40.8% of patients had nonnephrotic proteinuria, 18.4% nephrotic syndrome (NS), 4.1% nephritic syndrome (NephrS), and 36.7% NephrS+NS. There were 11 patients with an estimated glomerular filtration rate below 90 ml/min/1.73 m2. Biopsy specimens were classified according to International Study of Kidney Diseases in Children (ISKDC) and Oxford Classification MEST-C scoring systems. Forty-one patients received angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, 37 patients steroids, and 35 patients other immunosuppressive medications. At last visit, 24 patients had stage 1 chronic kidney disease (CKD), three stage 2 CKD, and two had stage 5 CKD. Neither clinical parameters nor ISKDC biopsy grade or treatment modalities effected the final outcome. The Oxford classification showed significantly increased segmental glomerulosclerosis in patients with unfavorable outcome. Favorable outcome was associated with shorter time from kidney involvement to biopsy and start of treatment. CONCLUSION: A large proportion of patients continued to show signs of CKD at last follow-up while only a small proportion developed stage 5 CKD.

Association of kidney biopsy findings with short- and medium-term outcomes in children with moderate-to-severe IgA vasculitis nephritis.

Assessing the initial severity of immunoglobulin A vasculitis nephritis (IgAV-N) is important due to its determining effect on kidney management and outcomes. This paper describes a multicentre paediatric cohort of IgAV-N patients and discusses relationships among clinical presentation, histological features, and kidney outcome. We retrospectively studied a cohort of 170 children with biopsy-proven IgAV-N, diagnosed between 2007 and 2017. One-quarter of the cohort (27%) presented with initial nephrotic syndrome (NS). Kidney biopsy revealed International Study of Kidney Disease (ISKDC) grade II or grade III in 83% of cases. Endocapillary proliferation was observed in 73% of patients, and chronic lesions were observed in 25%. Data analysis showed a significant association between NS at onset and endocapillary proliferation and cellular crescents. After a median follow-up of 21 months (IQR 12-39), 30% of patients had persistent proteinuria or decreased eGFR. At the end of follow-up, kidney impairment was more often observed in patients with NS at onset and those with cellular crescents and chronic lesions on initial kidney biopsy.Conclusion: This study highlights the relationship between the clinical and histological presentation of IgAV-N and the factors that affect kidney outcome. The ISKDC classification may be improved by including lesions that are more discriminating for disease severity and prognosis. What is Known: • Nephrotic syndrome (NS) or kidney failure at diagnosis and cellular crescents in more than 50% of the glomeruli are recognized as risk factors for poor kidney outcome in immunoglobulin A vasculitis nephritis (IgAV-N). • The reference histological classification of the International Study of Kidney Disease in Children (ISKDC) is primarily based on the presence and number of affected glomeruli (mesangial proliferation, cellular crescents). The updated Oxford classification, which emphasizes tubular atrophy and interstitial fibrosis, is also used to group pathological features of IgAV-N. Both classifications have limitations. What is New: • Medical treatment should not be postponed in patients with IgAV-N and NS until after biopsy, as NS at diagnosis is associated with initial histological severity and poorer kidney outcome. This proposal needs to be verified in further studies. • Endocapillary proliferation is associated with the initial severity of IgAV-N at diagnosis, while chronic glomerular changes and interstitial fibrosis are associated with poorer short- and medium-term kidney outcomes.

Serum levels of galactose-deficient IgA1 in Chinese children with IgA nephropathy, IgA vasculitis with nephritis, and IgA vasculitis.

OBJECTIVE: IgA nephropathy (IgAN) and IgA vasculitis with nephritis (IgAV-N) are related diseases. Galactose-deficient IgA1 (Gd-IgA1) plays an important role in the pathology of IgAV-N and IgAN, so we aim to compare the serum levels of Gd-IgA1 in Chinese pediatric patients with IgAN, IgAV-N, and IgAV. METHODS: We retrospectively enrolled 52 patients with IgAN, 57 patients with IgAV-N, 26 patients with IgAV, and 40 healthy children. The serum levels of Gd-IgA1 were measured at the time of biopsy using a lectin-based ELISA method. RESULTS: Gd-IgA1 levels in IgAV-N patients and IgAN patients were higher than in healthy controls (303.94 ± 39.37 U/ml, 314.91 ± 47.79 U/ml vs. 273.57 ± 48.29 U/ml, P < 0.001), and Gd-IgA1 levels in IgAV-N patients were higher than in IgAV patients (303.94 ± 39/ml vs. 286. 21 ± 38.81 U/ml, P = 0.059), but the latter result is not statistically significant. The Gd-IgA1 levels in IgAV patients were comparable with those in healthy controls (286.21 ± 38.81 U/ml vs. 273.57 ± 48.29 U/ml, P = 0.267). Among the four groups, we did not observe significant correlations of Gd-IgA1 levels with eGFR, proteinuria, or the MEST-C score. CONCLUSION: Serum Gd-IgA1 maybe involved in the pathogenesis of the IgAV-N and IgAN. However, we found no statistically significant correlation between Gd-IgA1 levels and clinical and pathological features.

A Pooled Study of Angiotensin-Converting Enzyme Insertion/Deletion Gene Polymorphism in Relation to Risk, Pathology and Prognosis of Childhood Immunoglobulin A Vasculitis Nephritis.

The angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism has been inconsistently reported to be a risk factor for Childhood immunoglobulin A vasculitis (IgAV) nephritis. We comprehensively searched electronic databases as of Jan 2020. Nineteen studies with 1104 cases and 1589 controls were included. Sensitivity analyses based on different subgroups were performed. Further analyses were conducted for association of ACE polymorphism with disease severity and prognosis. Significant associations were found between ACE I/D polymorphism and childhood IgAV nephritis, with the strongest association in DD vs. II comparison (OR 1.72, 95% CI 1.21-2.46). Subgroup analyses generally showed significant results. Besides, ACE polymorphism was significantly associated with proteinuria (DD + DI vs. II: OR 2.22, 95% CI 1.14-4.33; DI + II vs. DD: OR 0.49, 95% CI 0.30-0.81) and worse prognosis (the strongest effect in DD + DI vs. II: OR 4.43, 95% CI 1.84-10.71) among children with IgAV nephritis. The ACE polymorphism seemed not to be associated with hematuria, hypertension, and renal pathology. This study suggested significant association of ACE gene polymorphism with the risk of IgAV nephritis in children. D allele in the ACE genotype could be a useful genetic marker to predict proteinuria and worse prognosis for childhood IgAV nephritis.

Early kidney injury in immunoglobulin A vasculitis: Role of renal biomarkers.

BACKGROUND: We aimed to determine whether urine kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) can be used as early noninvasive biomarkers of kidney injury in immunoglobulin A vasculitis. METHODS: Patients who were diagnosed with immunoglobulin A vasculitis were included in the study. Urine samples were collected for determination of urine KIM-1 and NGAL levels. The control group consisted of age-matched healthy children. RESULTS: Sixty-one patients who were diagnosed with immunoglobulin A vasculitis were included in the study; 37.7% of these patients were determined to have renal involvement. Median KIM-1 was found to be significantly higher in the patient group (69.59 pg/mL) than the control group (40.84 pg/mL) (P = 0.001). Median NGAL was determined to be statistically significantly higher in the patient group (59.87 ng/mL) compared with the control group (44.87 ng/mL) (P = 0.013). In 23.6% of the patients without renal involvement at admission renal involvement developed within the following 6 months. When median KIM-1 and NGAL at admission of these patients were compared with the control group, they were determined to be statistically significantly higher (P = 0.001, P = 0.003). CONCLUSIONS: The fact that our patients with late-term nephropathy had no hematuria and / or proteinuria and that KIM-1 and NGAL levels were determined to be high indicates that these biomarkers might be potentially reliable, noninvasive and early determinants of kidney injury.

Imbalanced Th17/Treg in peripheral blood of adult patients with immunoglobulin A vasculitis nephritis.

INTRODUCTION: Adult immunoglobulin A vasculitis nephritis (IgAVN) was observed to be more severe than the disease in children because it tended to result in a poor prognosis. The present study analyzed the Th17/Treg cell axis in peripheral blood of adult IgAVN patients, aiming to provide new immunological viewpoints for the pathogenesis of adult IgAVN. MATERIAL AND METHODS: Th17 cell and Treg cell frequencies in peripheral blood of healthy subjects (n = 13) and adult IgAVN patients (n = 12) were analyzed by flow cytometry. Foxp3 mRNA in peripheral blood of healthy subjects and adult IgAVN patients was detected by RT-PCR. Interleukin (IL)-17 and IL-10 in peripheral blood serum of healthy subjects and adult IgAVN patients were examined by ELISA. RESULTS: The percentages of CD4+ Th17+ cells in peripheral blood of healthy subjects and adult IgAVN patients were 2.65 ±1.55% and 4.37 ±1.68% respectively. The percentages of Treg cells in peripheral blood of healthy subjects and adult IgAVN patients were 6.44 ±2.90% and 3.91 ±1.94% respectively. The ratio of Th17/Treg in adult IgAVN patients was significantly higher than that of healthy subjects (p = 0.0030). Meanwhile, the Foxp3 mRNA expression of adult IgAVN patients was significantly lower than that of healthy subjects. There was a significant difference in the ratio of IL-17/IL-10 between healthy subjects and adult IgAVN patients (p < 0.0001). A significant correlation between red blood cell distribution width (RDW) and the ratio of Th17/Treg in adult IgAVN patients was observed in Spearman correlation analysis (r = 0.6970, p = 0.0145). CONCLUSIONS: Imbalanced Th17/Treg contributed to the complex pathogenesis of adult IgAVN.

Variation in complement factor H affects complement activation in immunoglobulin A vasculitis with nephritis.

BACKGROUND: Immunoglobulin A (IgA) vasculitis with nephritis (IgAVN) and IgA nephropathy (IgAN) are widely considered as related diseases. Considerable evidences support the notion of involvement of complement activation in both IgAVN and IgAN. Our previous studies identified a genetic variant in complement factor H (CFH), rs6677604, as an IgAN-susceptible variant by genome-wide association study, and further confirmed its linkage to CFHR3-1Δ and proved its influence on complement activation and thereby on IgAN susceptibility. AIM: To explore the role of rs6677604 in complement activation of IgAVN. METHODS: In this study, we enrolled 632 patients with IgAVN, 1178 patients with IgAN and 902 healthy controls. The genotype of rs6677604 was measured by TaqMan allele discrimination assays or was extracted from genome-wide association study data. RESULTS: The frequency of the rs6677604-A allele was significantly higher in IgAVN than in IgAN. However, no significant differences were observed between IgAVN and the controls. Higher complement factor H (FH) levels were observed in IgAVN than IgAN, and positive correlation between circulating FH and C3 levels was present in IgAVN. In both IgAVN and IgAN, rs6677604-A was associated with less intensity of glomerular C3 deposits. In agreement with the higher frequency of rs6677604-A in IgAVN, the glomerular C3 deposits of patients with IgAVN were less intense than those in IgAN. CONCLUSION: Our findings suggest that genetic variation in CFH (rs6677604) is involved in the phenotype of complement activation in both IgAVN and IgAN. Moreover, rs6677604 might contribute to the difference of complement activation intensity between IgAVN and IgAN.

Management of Primary Small-Vessel Vasculitis.

Small-vessel vasculitides (SVV) are a group of disorders that occur due to primarily systemic inflammation or as sequelae of an infection, malignancy, or other rheumatic disease. Arising in any organ including the skin, the clinical features of SVV encompass a variety of manifestations. A comprehensive diagnostic assessment should be performed as management protocols widely differ. Although rare, physicians should be familiar with the common types of SVV to ensure prompt management and prevention of severe, life-threatening end-organ damage. Given the variable manifestations and associated etiologies of SVV, the following review aims to discuss the pathogenesis of more prevalent SVVs, highlight distinguishing features to aid in patient evaluation and diagnosis, and examine evidence-based management options for treatment and care.