The pathogenesis of COVID-19-induced IgA nephropathy and IgA vasculitis: A systematic review

Incidence and pathological features of IgA nephropathy before and during the COVID-19 pandemic

IgA nephropathy (IgAN) imposes a substantial burden of illness and death. However, a systematic evaluation of the impact of the COVID-19 pandemic on the incidence and pathology of IgAN has yet to be performed. In this study, we analyzed kidney biopsy results from two medical institutions, covering the timeframe from January 2016 to May 2023. We conducted statistical analyses on various glomerular diseases according to their corresponding pathological diagnoses. Our objective was to compare the incidence of different glomerular diseases before and during the COVID-19 pandemic. The study focused on variations in the incidence of IgAN, and collected clinical and pathological data to assess pathological changes using the Oxford Classification (MEST-C). The findings revealed a significant increase in the incidence of IgAN during the COVID-19 pandemic, from 39.9% prior to the pandemic to 46.3% during it, representing a net increase of 6.4% (P < 0.001). Although clinical manifestations and laboratory indicators of disease activity in IgAN patients remained consistent over both periods, observable changes occurred in pathological features. Specifically, the proportions of M1 and E1 lesions according to the Oxford classification significantly increased during the pandemic, with odds ratios of 11.764 (95% CI 5.583-24.789, P < 0.001) and 1.718 (95% CI 1.114-2.649, P = 0.014), respectively. Our results indicate that the incidence of IgAN has risen during the COVID-19 pandemic, along with exacerbated renal damage and elevated proportions of M1 and E1 in the Oxford classification.

The influence of respiratory infections on Henoch-Schönlein purpura in children

OBJECTIVE

To explore the influence of respiratory infections on the onset of Henoch-Schönlein Purpura (HSP) in children, along with exploring potential underlying mechanisms.

METHOD

The present study conducted a statistical analysis on renal involvement indicators in 296 children with HSP who came to the Children's Hospital of Zhejiang University, as well as the IgA levels in 400 children with respiratory infections and 400 children with HSP.

RESULTS

Compared with the control group, children with HSP exhibited a significant increase in urine red blood cell count, urine microalbuminuria, and urine protein/creatinine ratio (P < 0.001). The monthly outpatient visits for children with respiratory infections exhibited a similar pattern to those with HSP, demonstrating a heightened prevalence during the autumn and winter. The level of IgA in children with respiratory infections and HSP were significantly higher than those in the control group (P < 0.001).

CONCLUSION

HSP can give rise to complications such as renal involvement. There exists a certain correlation between respiratory infections and the occurrence of HSP, which may be attributed to the elevation of IgA induced by respiratory infections. In conclusion, children with HSP should reinforce protective measures during the peak influenza season in order to prevent respiratory infections.

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.

Proteomic analysis of lung responses to SARS-CoV-2 infection in aged non-human primates: clinical and research relevance

With devastating health and socioeconomic impact worldwide, much work is left to understand the Coronavirus Disease 2019 (COVID-19), with emphasis in the severely affected elderly population. Here, we present a proteomics study of lung tissue obtained from aged vs. young rhesus macaques (Macaca mulatta) and olive baboons (Papio Anubis) infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Using age as a variable, we identified common proteomic profiles in the lungs of aged infected non-human primates (NHPs), including key regulators of immune function, as well as cell and tissue remodeling, and discuss the potential clinical relevance of such parameters. Further, we identified key differences in proteomic profiles between both NHP species, and compared those to what is known about SARS-CoV-2 in humans. Finally, we explored the translatability of these animal models in the context of aging and the human presentation of the COVID-19.

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.

IgA vasculitis after COVID-19: a case-based review

IgA-associated vasculitis (IgAV) known as Henoch - Schönlein purpura (HSP) disease is an inflammatory disorder of small blood vessels. It's the most common type of systemic vasculitis in children which can be associated with the inflammatory process following infections. IgA vasculitis is a rare and poorly understood systemic vasculitis in adults. Coronavirus disease 2019 (COVID-19) has been associated with HSP in both adults and children. A 58-year-old woman was diagnosed with HSP, fulfilling the clinical criteria: palpable purpura, arthritis, hematuria. The disclosure of the HSP disease was preceded by a infection of the respiratory tract. COVID-19 infection was confirmed via the presence of IgM and IgG antibodies. This case indicates the possible role of SARS-CoV-2 in the development of HSP. The clinical course of IgAV in adults appears to be different from pediatric IgAV, especially due to higher risk of renal complications. Symptoms of the disease quickly resolved with low-dose of steroids.

Outcome Comparison in Hospitalized COVID-19 Patients With and Without AKI

Aim

Patients hospitalized with COVID-19 have a higher incidence of Acute Kidney Injury (AKI) compared with non-COVID patients. Previous observational studies showed AKI in hospitalized patients with COVID-19 was associated with significant increased mortality rate. We conducted a retrospective cohort study in a large mid-Atlantic health system to investigate whether COVID-19 associated AKI during hospitalization would lead to worse outcomes in a predominant Black patient population, compared to COVID-19 without AKI.

Methods

We reviewed health records of patients (aged≥18 years) admitted with symptomatic COVID-19 between March 5, 2020, and Jun 3, 2020, in 9 acute care facilities within the MedStar Health system. Patients were followed up until 3 months after discharge. Primary outcome was inpatient mortality. Secondary outcomes were need for ICU level of care, need for intubation, length of ICU stay, length of hospital stay, need for renal replacement therapy, recovery of renal function.

Results

Among 1107 patients admitted with symptomatic COVID-19, the AKI incidence rate was 35 %. African American patients made up 63 % of the total patient population and 74 % of the total AKI population. Inpatient mortality in the AKI group and the non-AKI group was 163 (41.9 %) and 71 (9.9 %), respectively. COVID-19 patients with AKI had significant higher risk of in-patient mortality (OR, 4.71 [95 % CI, 3.38-6.62], P < 0.001), ICU admission (OR, 4.27 [95 % CI, 3.21-5.72], P < 0.001) and need of intubation (OR, 6.18 [95 % CI, 4.45-8.68], P < 0.001).

Conclusions

AKI in hospitalized patients with COVID-19 was associated with higher mortality rate, need for intubation and ICU admission compared to COVID-19 patients without AKI group.

Clinical and pathological findings of IgA nephropathy following SARS-CoV-2 infection

The features of IgA nephropathy (IgAN) after SARS-CoV-2 infection have not been well characterized. In this study, we compared the clinical and pathological characteristics of patients with IgAN who had experienced SARS-CoV-2 infection to those who had not. We conducted a retrospective study that enrolled 38 patients with biopsy-proven IgAN following SARS-CoV-2 infection with 4 months (post-SARS-CoV-2 infection group) and 1154 patients with IgAN prior to the pandemic (pre-SARS-CoV-2 infection group). Among the SARS-CoV-2 group cases, 61% were females. The average duration from SARS-CoV-2 infection to renal biopsy was 78.6 days. Prior to SARS-CoV-2 infection, the patients had different presentations of nephropathy. One patient had isolated hematuria, two had isolated proteinuria, twenty presented with both hematuria and proteinuria, and one patient had elevated serum creatinine. Additionally, there were eight cases with uncertain nephropathy history, and six cases did not have a history of nephropathy. Following SARS-CoV-2 infection, five patients experienced gross hematuria, one case exhibited creatinine elevation, and five cases showed an increase in proteinuria. The group of patients infected with SARS-CoV-2 after the COVID-19 pandemic exhibited older age, higher hypertension ratio and lower eGFR values compared to the pre-SARS-CoV-2 infection group. As for pathological parameters, a higher proportion of patients in the post-SARS-CoV-2 infection group exhibited a higher percentage of sclerotic glomeruli and glomerular ischemic sclerosis. There were no significant differences observed between the two groups in terms of therapy involving steroids, immunosuppressants, or RAS inhibitors. IgA nephropathy patients who were infected with SARS-CoV-2 were generally older and experienced more severe kidney damage compared to those without SARS-CoV-2 infection.

Traditional Chinese medicine for the treatment of immune-related nephropathy: A review

Immune-related nephropathy (IRN) refers to immune-response-mediated glomerulonephritis and is the main cause of end-stage renal failure. The pathogenesis of IRN is not fully understood; therefore, treatment is challenging. Traditional Chinese medicines (TCMs) have potent clinical effects in the treatment of the IRN conditions immunoglobulin A nephropathy, lupus nephropathy, and diabetic nephropathy. The underlying mechanisms mainly include its inhibition of inflammation; improvements to renal interstitial fibrosis, oxidative stress, autophagy, apoptosis; and regulation of immunity. In this review, we summarize the clinical symptoms of the three IRN subtypes and the use of TCM prescriptions, herbs, and bioactive compounds in treating IRN, as well as the potential mechanisms, intending to provide a reference for the future study of TCM as IRN treatments.

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

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

SARS-CoV-2 infection: a possible trigger for the recurrence of IgA nephropathy after kidney transplantation?

Immunoglobulin A nephropathy, the most common primary glomerulonephritis worldwide, is a leading cause of chronic kidney disease and end-stage kidney failure. Several cases of immunoglobulin A nephropathy relapse in native kidneys have been described after COVID-19 vaccination or SARS-CoV-2 infection. Here, we report the case of a 52-year-old kidney transplant recipient who had a stable transplant function for more than 14 years, with a glomerular filtration rate above 30 ml/min/1.73 m². The patient had been vaccinated against COVID-19 four times with the Pfizer-BioNTech vaccine, most recently in March 2022. Eight weeks after a symptomatic SARS-CoV-2 infection in June 2022, his glomerular filtration rate had decreased by more than 50%, and his proteinuria increased to 17.5 g per day. A renal biopsy indicated highly active immunoglobulin A nephritis. Despite steroid therapy, the function of the transplanted kidney deteriorated, and long-term dialysis became necessary because of recurrence of his underlying renal disease. This case report provides what is, to our knowledge, the first description of recurrent immunoglobulin A nephropathy in a kidney transplant recipient after SARS-CoV-2 infection leading to severe transplant failure and finally graft loss.

The relationship of skin disorders, COVID-19, and the therapeutic potential of ginseng: a review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made significant impacts on global public health, including the development of several skin diseases that have arisen primarily as a result of the pandemic. Owing to the widespread expansion of coronavirus disease 19 (COVID-19), the development of effective treatments for these skin diseases is drawing attention as an important social issue. For many centuries, ginseng and its major active ingredients, ginsenosides and saponins, have been widely regarded as herbal medicines. Further, the anti-viral action of ginseng suggests its potential effectiveness as a therapeutic agent against COVID-19. Thus, the aim of this review was to examine the association of skin lesions with COVID-19 and the effect of ginseng as a therapeutic agent to treat skin diseases induced by COVID-19 infection. We classified COVID-19-related skin disorders into three categories: caused by inflammatory, immune, and complex (both inflammatory and immune) responses and evaluated the evidence for ginseng as a treatment for each category. This review offers comprehensive evidence on the improvement of skin disorders induced by SARS-CoV-2 infection using ginseng and its active constituents.

Incidence of new onset glomerulonephritis after SARS-CoV-2 mRNA vaccination is not increased

Numerous cases of glomerulonephritis manifesting shortly after SARS-CoV-2 vaccination have been reported, but causality remains unproven. Here, we studied the association between mRNA-based SARS-CoV-2 vaccination and new-onset glomerulonephritis using a nationwide retrospective cohort and a case-cohort design. Data from all Swiss pathology institutes processing native kidney biopsies served to calculate incidence of IgA nephropathy, pauci-immune necrotizing glomerulonephritis, minimal change disease, and membranous nephropathy in the adult Swiss population. The observed incidence during the vaccination campaign (January to August 2021) was not different from the expected incidence calculated using a Bayesian model based on the years 2015 to 2019 (incidence rate ratio 0.86, 95% credible interval 0.73-1.02) and did not cross the upper boundary of the 95% credible interval for any month. Among 111 patients 18 years and older with newly diagnosed glomerulonephritis between January and August 2021, 38.7% had received at least one vaccine dose before biopsy, compared to 39.5% of the general Swiss population matched for age and calendar-time. The estimated risk ratio for the development of new-onset biopsy-proven glomerulonephritis was not significant at 0.97 (95% confidence interval 0.66-1.42) in vaccinated vs. unvaccinated individuals. Patients with glomerulonephritis manifesting within four weeks after vaccination did not differ clinically from those manifesting temporally unrelated to vaccination. Thus, vaccination against SARS-CoV-2 was not associated with new-onset glomerulonephritis in these two complementary studies with most temporal associations between SARS-CoV-2 vaccination and glomerulonephritis likely coincidental.

Do we miss rare adverse events induced by COVID-19 vaccination?

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused many complications, the invention of coronavirus disease 2019 (COVID-19) vaccines has also brought about several adverse events, from common side effects to unexpected and rare ones. Common vaccine-related adverse reactions manifest locally or systematically following any vaccine, including COVID-19 vaccines. Specific side effects, known as adverse events of particular interest (AESI), are unusual and need more evaluation. Here, we discuss some of the most critical rare adverse events of COVID-19 vaccines.

Immunoglobulin A Nephropathy in a SARS-CoV-2-Positive Patient With Coexistent Metabolic Syndrome

SARS-CoV-2 viral infection though primarily affects the respiratory system, but concurrent renal involvement is been reported in the medical literature. Acute kidney injury (AKI) is a common finding in SARS-CoV-2-positive patients. An isolated case of IgA nephropathy in a SARS-CoV-2 virus-infected patient has been already reported in the medical literature. Incidence of metabolic syndromes is on the rise considering the change in lifestyle and food habits and the global pandemic of obesity. Renal manifestations of metabolic syndrome are myriad with IgA nephropathy being an occasional manifestation in such patients. We reported a case of IgA nephropathy in a patient in her fourth decade of life diagnosed as metabolic syndrome with concomitant SARS-CoV-2 infection that progressed to chronic kidney damage (CKD) subsequently. In this case report, we postulate that cytokine storm along with hypoxemia secondary to SARS-CoV-2 infection may accelerate the declining renal function however further studies are necessary to confirm this hypothesis considering the rarity of such cases.

Immunoglobulin A Vasculitis Associated With COVID-19 Infection Successfully Treated With Corticosteroid Regimen Without Relapse

Immunoglobulin A (IgA) vasculitis is an autoimmune disease associated with bacterial and viral infections that typically presents with palpable purpura, arthralgia, abdominal pain, and renal involvement. Coronavirus disease 2019 (COVID-19) infection has been found to trigger numerous autoimmune and rheumatologic conditions, including IgA vasculitis. We report a patient who had a COVID-19 infection and then two weeks later developed severe abdominal pain, nausea, emesis, diarrhea, hematochezia, palpable purpura, and arthralgia. Skin biopsy revealed deposition of IgA and C3 complement granular deposition with fibrinogen deposition in superficial dermal vessel walls consistent with IgA vasculitis. The patient was treated with intravenous methylprednisolone followed by oral prednisone with significant improvement and no relapse after tapering and discontinuing steroids in six weeks. This case of biopsy-proven IgA vasculitis precipitated by active COVID-19 infection demonstrates the ability of COVID-19 infection to induce IgA vasculitis and its response to corticosteroid treatment.

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

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

COVID-19 and kidney disease: insights from epidemiology to inform clinical practice

Over the course of the COVID-19 pandemic, numerous studies have aimed to address the challenges faced by patients with kidney disease and their caregivers. These studies addressed areas of concern such as the high infection and mortality risk of patients on in-centre haemodialysis and transplant recipients. However, the ability to draw meaningful conclusions from these studies has in some instances been challenging, owing to barriers in aspects of usual care, data limitations and problematic methodological practices. In many settings, access to SARS-CoV-2 testing differed substantially between patient groups, whereas the incidence of SARS-CoV-2 infection varied over time and place because of differences in viral prevalence, targeted public health policies and vaccination rates. The absence of baseline kidney function data posed problems in the classification of chronic kidney disease and acute kidney injury in some studies, potentially compromising the generalizability of findings. Study findings also require attentive appraisal in terms of the effects of confounding, collider bias and chance. As this pandemic continues and in the future, the implementation of sustainable and integrated research infrastructure is needed in settings across the world to minimize infection transmission and both prevent and plan for the short-term and long-term complications of infectious diseases. Registries can support the real-world evaluation of vaccines and therapies in patients with advanced kidney disease while enabling monitoring of rare complications.

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.

COVID-19 Associated Illnesses From Alveoli to Glomeruli: A Case Report

Hypoxemic respiratory failure is the most frequent complication of severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) infection. Coronavirus disease-19 (COVID-19) is no longer considered a standalone respiratory infection. It can involve other organs, including kidneys by direct invasion or indirectly through immune activation, cytokine storm, microthrombi and hemodynamic instability. Multiorgan involvement carries a worse prognosis in COVID-19. Tubulopathy is the most frequently reported renal pathology, followed by glomerulopathies. Among the glomerulopathies, immunoglobulin A (IgA) nephropathy is less often reported. Differentiating tubulopathy from glomerulopathy is important from the management and prognostic point of view. Laboratory investigations, including urine microscopy, cannot predict glomerulopathy as a cause of renal involvement. Therefore, it is important to proceed with renal biopsy early to make a definite diagnosis. We report a case of a 33-year-old male who presented three weeks after recovery from COVID-19 with proteinuric acute kidney injury. Subsequent renal biopsy revealed IgA nephropathy.

Overview of infections as an etiologic factor and complication in patients with vasculitides

Vasculitides, a form of inflammatory autoimmune disease targeting the vessels, constitute an entity with significant morbidity and mortality. Infections have long been associated with vasculitides as a result of the incident immunosuppression following treatment induction and maintenance. Several microbial pathogens have been described as etiologic factors of infections in this patient population according to the type of vessels affected. Intense research has also been recently conducted in the interplay between vasculitides and certain viral infections, namely human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2. Of note, a plethora of scientific evidence is available regarding the role of infections as triggering factors for vasculitides. Among the main mechanisms implicated in this direction are the activation of B and T cells, the direct endothelial insult, the immune complex-mediated vascular injury, and the cell-mediated, type IV hypersensitivity vessel damage. Therefore, this review aims to summarize all the available evidence concerning this bidirectional interplay between infections and vasculitides.

COVID-19 Vasculitis and vasculopathy-Distinct immunopathology emerging from the close juxtaposition of Type II Pneumocytes and Pulmonary Endothelial Cells

The SARS-CoV-2 virus ACE-2 receptor utilization for cellular entry and the defined ACE-2 receptor role in cardiovascular medicine hinted at dysregulated endothelial function or even direct viral endotheliitis as the key driver of severe COVID-19 vascular immunopathology including reports of vasculitis. In this article, we critically review COVID-19 immunopathology from the vasculitis perspective and highlight the non-infectious nature of vascular endothelial involvement in severe COVID-19. Whilst COVID-19 lung disease pathological changes included juxta-capillary and vascular macrophage and lymphocytic infiltration typical of vasculitis, we review the evidence reflecting that such “vasculitis” reflects an extension of pneumonic inflammatory pathology to encompass these thin-walled vessels. Definitive, extrapulmonary clinically discernible vasculitis including cutaneous and cardiac vasculitis also emerged- namely a dysregulated interferon expression or “COVID toes” and an ill-defined systemic Kawasaki-like disease. These two latter genuine vasculitis pathologies were not associated with severe COVID-19 pneumonia. This was distinct from cutaneous vasculitis in severe COVID-19 that demonstrated pauci-immune infiltrates and prominent immunothrombosis that appears to represent a novel immunothrombotic vasculitis mimic contributed to by RNAaemia or potentially diffuse pulmonary venous tree thrombosis with systemic embolization with small arteriolar territory occlusion, although the latter remains unproven. Herein, we also performed a systematic literature review of COVID-19 vasculitis and reports of post-SARS-CoV-2 vaccination related vasculitis with respect to the commonly classified pre-COVID vasculitis groupings. Across the vasculitis spectrum, we noted that Goodpasture’s syndrome was rarely linked to natural SARS-CoV-2 infection but not vaccines. Both the genuine vasculitis in the COVID-19 era and the proposed vasculitis mimic should advance the understanding of both pulmonary and systemic vascular immunopathology.

Development of IgA vasculitis with severe glomerulonephritis after COVID-19 vaccination: a case report and literature review

With the worldwide spread of the COVID-19 vaccine program during the COVID-19 pandemic, the numbers of reported cases with new-onset or relapsed kidney disease/vasculitis such as minimal change nephrotic syndrome, immunoglobulinA (IgA) nephropathy, and IgA vasculitis (IgAV) that developed after COVID-19 vaccination are increasing. We present the case of a 67-year-old Japanese woman who developed IgAV with purpura on her extremities and trunk in the evening of the day that she received the second dose of the Pfizer-BioNTech COVID-19 vaccine. She subsequently presented with acute kidney injury and nephrotic syndrome, and a kidney biopsy performed 14 days after the second vaccination showed diffuse mesangial and endocapillary glomerulonephritis with necrotizing crescent formation, accompanied by IgA deposition. One steroid pulse plus four administrations of a monthly intravenous cyclophosphamide injection were applied, followed by oral azathioprine during oral steroid tapering. Her response to this treatment was unsatisfactory and intractable for some time. Eventually, her renal function improved and nephrotic syndrome was resolved, while microscopic hematuria and proteinuria at ~ 1 g/gCr remained at 6 months post-vaccination. Unlike the previous milder renal-involved IgAV cases following COVID-19 vaccination, our patient’s case presented severe glomerulonephritis and took a long time to recover despite intensive initial immunosuppressive treatment.