COVID-19 associated pediatric vasculitis: A systematic review and detailed analysis of the pathogenesis

The past 25 years in paediatric rheumatology: insights from monogenic diseases

The past 25 years have seen major novel developments in the field of paediatric rheumatology. The concept of autoinflammation was introduced to this field, and medicine more broadly, with studies of familial Mediterranean fever, the most common autoinflammatory disease globally. New data on the positive evolutionary selection of familial Mediterranean fever-associated genetic variants might be pertinent to mild gain-of-function variants reported in other disease-associated genes. Genetic studies have unveiled the complexity of human heritability to inflammation and flourishing data from rare monogenic disorders have contributed to a better understanding of general disease mechanisms in paediatric rheumatic conditions. Beyond genomics, the application of other 'omics' technologies, including transcriptomics, proteomics and metabolomics, has generated an enormous dataset that can be applied to the development of new therapies and in the practice of precision medicine. Novel biomarkers for monitoring disease activity and progression have also emerged. A surge in the development of targeted biologic therapies has led to durable remission and improved prognosis for many diseases that in the past caused major complications. Last but not least, the COVID-19 pandemic has affected paediatric rheumatology practice and has sparked new investigations into the link between viral infections and unregulated inflammatory responses in children.

Myeloperoxidase Anti-Neutrophil Cytoplasmic Antibody (MPO-ANCA)-Associated Vasculitis With Rare Clinical Manifestations After SARS-CoV-2 Multisystem Inflammatory Syndrome in a 14-Year-Old Boy

Myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) microscopic polyangiitis is a rare but life-threatening small vessel vasculitis in childhood that affects multiple systems. Emerging clinical evidence suggests a possible association between SARS-CoV-2 infection or multisystem inflammatory syndrome in children (MIS-C) as well as the futuredevelopment of autoimmune diseases. A 14-year-old boy with a diagnosis of MIS-C two years prior to presentation was admitted to our hospital due to edema and left lower limb joint pain along with concomitant upper surface petechia. The patient had a positive higher SARS-CoV-2 IgG than MIS-C diagnosis titers and MPO-ANCA-positive antibody titers. Kidney biopsy favored a pauci-immune crescentic glomerulonephritis. Restrictive lung disease with concomitant diffusion abnormalities was also observed. Pancreatitis and gastrointestinal wall edema were additional clinical manifestations. SARS-CoV-2 breakthrough infection and MIS-C could contribute to the onset of autoimmune vasculitis through various immunological mechanisms. Further research is still needed to elucidate the role of SARS-CoV-2 in the pathophysiology of newly diagnosed autoimmune vasculitis.

Update on antineutrophil cytoplasmic autoantibody vasculitis in children

PURPOSE OF REVIEW

Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) is often organ- or life-threatening in children and impacts them during important periods of psychosocial and physical development. This review covers recent advances in the pathophysiology, diagnosis, management, and outcomes of AAV in children and highlights the ongoing need for funding and increased research collaboration.

RECENT FINDINGS

Recent work has improved our understanding of AAV disease pathogenesis, potentially identifying new biomarkers and therapeutic targets. Collaborative clinical studies have also highlighted the variable manifestations in children and identified potential factors associated with poorer outcomes. Consensus-based treatment guidelines are also appearing, but clinical trials are still essential to better understanding treatment efficacy and safety in children affected by AAV. New, validated outcome measures, including those that are patient-reported, will facilitate these much-needed clinical trials in pediatric AAV.

SUMMARY

There is a continued need for more rigorous study in pediatric AAV, however, there is certainly excitement with the increase in recent research relevant to the pediatric population.

Immunoglobulin A vasculitis: The clinical features and pathophysiology

Palpable purpura, gastrointestinal symptoms, joint involvement, and renal disease characterize immunoglobulin A vasculitis (IgAV). Renal involvement ranging from mild proteinuria to severe nephritic or nephrotic syndrome highlights the importance of monitoring kidney function in patients with IgAV. Recognizing these key features is crucial for early diagnosis and appropriate management to prevent long-term complications related to kidney disease. However, the pathogenesis of IgAV remains unclear. Disease mechanisms involve various factors, including the interplay of aberrantly glycosylated IgA, anti-endothelial cell antibodies, and neutrophils following infection triggers, which are the main pathogenic mechanisms of IgAV. Insights from cases of IgAV related to Coronavirus disease 2019 have offered additional understanding of the connection between infection and IgAV pathogenesis. This review provides a valuable resource for healthcare professionals and rheumatology researchers seeking a better understanding of the clinical features and pathophysiology of IgAV.

Effect and mechanism of quercetin or quercetin-containing formulas against COVID-19: From bench to bedside

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the global coronavirus disease 2019 (COVID-19) pandemic since 2019. Immunopathogenesis and thromboembolic events are central to its pathogenesis. Quercetin exhibits several beneficial activities against COVID-19, including antiviral, anti-inflammatory, immunomodulatory, antioxidative, and antithrombotic effects. Although several reviews have been published, these reviews are incomplete from the viewpoint of translational medicine. The authors comprehensively evaluated the evidence of quercetin against COVID-19, both basically and clinically, to apply quercetin and/or its derivatives in the future. The authors searched the PubMed, Embase, and the Cochrane Library databases without any restrictions. The search terms included COVID-19, SARS-CoV-2, quercetin, antiviral, anti-inflammatory, immunomodulatory, thrombosis, embolism, oxidative, and microbiota. The references of relevant articles were also reviewed. All authors independently screened and reviewed the quality of each included manuscript. The Cochrane Risk of Bias Tool, version 2 (RoB 2) was used to assess the quality of the included randomized controlled trials (RCTs). All selected studies were discussed monthly. The effectiveness of quercetin against COVID-19 is not solid due to methodological flaws in the clinical trials. High-quality studies are also required for quercetin-containing traditional Chinese medicines. The low bioavailability and highly variable pharmacokinetics of quercetin hinder its clinical applications. Its positive impact on immunomodulation through reverting dysbiosis of gut microbiota still lacks robust evidence. Quercetin against COVID-19 does not have tough clinical evidence. Strategies to improve its bioavailability and/or to develop its effective derivatives are needed. Well-designed RCTs are also crucial to confirm their effectiveness in the future.

A rare twist: COVID-19 infection masquerading as IgA vasculitis in a hemophilia a patient

Hemophilia A and B are one of the most common hereditary bleeding disorders. Patients are predisposed to bleeding spontaneously or after minor trauma in different areas such as the skin, gastrointestinal, or joints. COVID-19 infection has been associated with various clinical manifestations and complications including rarely triggering IgA vasculitis. We report a 23-year-old man who was previously diagnosed with severe hereditary hemophilia A. He presented to our hospital with classic symptoms of IgA vasculitis, complaining of petechiae and purpura in his limbs, fatigue, body aches, poor oral intake, abdominal pain, and watery non-bloody diarrhea. He did not present with respiratory symptoms or fever typical of COVID-19 infection. Abnormal blood tests were mildly elevated C-reactive protein, elevated d-dimers, and low Factor VIII activity. Extensive immunological tests were negative. CT abdomen with contrast was unremarkable. A skin biopsy strongly indicated IgA vasculitis. COVID-19 test came back positive. The patient was managed symptomatically and with glucocorticosteroids which significantly improved his symptoms. The available literature on clinical features, laboratory tests, and management of COVID-19-associated IgA vasculitis is discussed. However, there is no case reported on the associations between hemophilia, COVID-19 infection, and IgA vasculitis. This is the first case of atypical COVID-19 infection masquerading as de novo IgA vasculitis in an adult patient with underlying hemophilia. Our case contributes to the growing body of literature about hemophilia being a possible predisposing factor that a COVID-19 virus relies on to amplify immune dysregulation resulting in IgA vasculitis.

The impact of the COVID-19 pandemic on pediatric rheumatology practice: an international, cross-sectional survey study

OBJECTIVE

The COVID-19 pandemic has affected patient care in general. We aimed to analyze the impact of the pandemic on pediatric rheumatology practice.

METHODS

An online survey including 22 questions was created by the representatives of the Emerging RheumatoloGists and rEsearchers (EMERGE) group of the Pediatric Rheumatology European Society (PReS) on SurveyMonkey. The descriptive analysis of the responses was performed on SurveyMonkey.

RESULTS

Overall, 469 pediatric rheumatologists (F/M: 2.9) from 70 countries completed the survey. The practice of drug prescription is not affected by the pandemic, according to 65.3 % of the respondents, while 24.3 % and 16.5 % are prescribing biologic drugs and corticosteroids less often, respectively. Over 40 % of the respondents have seen an increased number of patients with vasculitis or chilblains during the pandemic. One-third of the respondents stated no adjustments in their clinical practice after 2.5 years of COVID-19 pandemic. The rest indicated implementing various changes, with an emphasis on incorporating telemedicine. Telemedicine constitutes ≥10 % of the clinical practice for one-third of the participants. Nonetheless, 35.5 % agree that there are still delays in patient care due to the pandemic. However, most (∼90 %) think our practice is returning to the pre-pandemic routine.

CONCLUSION

The findings of our study indicate a significant alteration in pediatric rheumatology practice due to the pandemic. This includes increased caution when prescribing anti-rheumatic drugs, a transition towards telemedicine utilization, delays in routine care, and a rise in COVID-19-related inflammatory conditions. It is imperative to address these aspects in order to improve patient care in pediatric rheumatology.

Childhood primary angiitis of the central nervous system following COVID-19 vaccination (BNT162b2/Pfizer-BioNtech): A case report

Childhood primary angiitis of the central nervous system (cPACNS) is a vasculitis of unknown etiology that is confined to the central nervous system (CNS) and can lead to repeated cerebral infarctions if left untreated. Several cases of cPACNS after COVID-19 have been reported. Herein, we present a case of post-vaccination cPACNS. A 9-year-old healthy boy presented with persistent headache and fever after receiving the second COVID-19 vaccine (BNT162b2/Pfizer-BioNtech) dose. Brain magnetic resonance angiography (MRA) performed on the sixth day of symptom onset after vaccination revealed stenosis of the left middle cerebral artery; the patient was referred to our department on the 12th day of symptom onset. Blood tests indicated only minimal evidence of inflammation, whereas cerebrospinal fluid examination indicated pleocytosis. Brain magnetic resonance imaging (MRI) revealed vascular wall thickening and contrast enhancement of the artery with worsened stenosis. We diagnosed the patient as having cPACNS and treated him with three courses of methylprednisolone pulse therapy. The headaches and fever disappeared with improvement of vascular stenosis. The patient has been in remission for more than 1 year since cPACNS onset. This is the first report of a case of cPACNS after mRNA vaccination for COVID-19. Most previous cases of COVID-19-associated cPACNS presented with ischemic stroke. However, the present case could be treated for vasculitis prior to stroke and thus had a favorable prognosis. The mRNA vaccine for COVID-19 differs from other existing vaccines, and further accumulation of data of cases is required to determine adverse CNS reactions.

SARS-CoV-2 and Its Bacterial Co- or Super-Infections Synergize to Trigger COVID-19 Autoimmune Cardiopathies

Autoimmune cardiopathies (AC) following COVID-19 and vaccination against SARS-CoV-2 occur at significant rates but are of unknown etiology. This study investigated the possible roles of viral and bacterial mimicry, as well as viral-bacterial co-infections, as possible inducers of COVID-19 AC using proteomic methods and enzyme-linked immunoadsorption assays. BLAST and LALIGN results of this study demonstrate that SARS-CoV-2 shares a significantly greater number of high quality similarities to some cardiac protein compared with other viruses; that bacteria such as Streptococci, Staphylococci and Enterococci also display very significant similarities to cardiac proteins but to a different set than SARS-CoV-2; that the importance of these similarities is largely validated by ELISA experiments demonstrating that polyclonal antibodies against SARS-CoV-2 and COVID-19-associated bacteria recognize cardiac proteins with high affinity; that to account for the range of cardiac proteins targeted by autoantibodies in COVID-19-associated autoimmune myocarditis, both viral and bacterial triggers are probably required; that the targets of the viral and bacterial antibodies are often molecularly complementary antigens such as actin and myosin, laminin and collagen, or creatine kinase and pyruvate kinase, that are known to bind to each other; and that the corresponding viral and bacterial antibodies recognizing these complementary antigens also bind to each other with high affinity as if they have an idiotype-anti-idiotype relationship. These results suggest that AC results from SARS-CoV-2 infections or vaccination complicated by bacterial infections. Vaccination against some of these bacterial infections, such as Streptococci and Haemophilus, may therefore decrease AC risk, as may the appropriate and timely use of antibiotics among COVID-19 patients and careful screening of vaccinees for signs of infection such as fever, diarrhea, infected wounds, gum disease, etc.

IgA Vasculitis Associated With COVID-19

IgA vasculitis, also known as Henoch-Schonlein Purpura (HSP), is an inflammatory disorder of small blood vessels that can present with palpable purpura, arthralgias, abdominal pain, and kidney disease. It is most commonly found in pediatric patients after an inciting infection but has been seen across all ages and associated with certain drugs and vaccines. COVID-19 has been associated with various cutaneous manifestations, but HSP is a rarely reported one. We present a case of a 21-year-old female presenting with a petechial rash found to be seronegative IgA vasculitis presenting concurrently with dyspnea secondary to COVID-19. She was initially seen by an outside practitioner, tested negative for COVID, and was prescribed a course of oral prednisone. Shortly thereafter, she visited the ED for worsening shortness of breath and tested positive for COVID-19, for which she received Paxlovid. Biopsy after a visit to a dermatologist confirmed intramural IgA deposition on immunofluorescence, and she was tapered off prednisone and started on azathioprine.

The Characteristics of Patients With COVID-19-Associated Pediatric Vasculitis: An International, Multicenter Study

OBJECTIVE

COVID-19-associated pediatric vasculitis, other than Kawasaki disease (KD)-like vasculitis in multisystem inflammatory syndrome in children (MIS-C), is very rare. This study sought to analyze the characteristics, treatment, and outcomes in patients with COVID-19-associated pediatric vasculitis (excluding KD-like vasculitis in MIS-C).

METHODS

The inclusion criteria were as follows: 1) age <18 years at vasculitis onset; 2) evidence of vasculitis; 3) evidence of SARS-CoV-2 exposure; and 4) ≤3 months between SARS-CoV-2 exposure and vasculitis onset. Patients with MIS-C were excluded. The features of the subset of patients in our cohort who had COVID-19-associated pediatric IgA vasculitis/Henoch Schönlein purpura (IgAV/HSP) were compared against a pre-pandemic cohort of pediatric IgAV/HSP patients.

RESULTS

Forty-one patients (median age 8.3 years; male to female ratio 1.3) were included from 14 centers and 6 countries. The most frequent vasculitis subtype was IgAV/HSP (n = 30). The median duration between SARS-CoV-2 exposure and vasculitis onset was 13 days. Involvement of the skin (92.7%) and of the gastrointestinal system (61%) were the most common manifestations of vasculitis. Most patients (68.3%) received glucocorticoids, and 14.6% also received additional immunosuppressive drugs. Remission was achieved in all patients. All of the patients with IgAV/HSP in our cohort had skin manifestations, while 18 (60%) had gastrointestinal involvement and 13 (43.3%) had renal involvement. When we compared the features of this subset of 30 patients to those of a pre-pandemic pediatric IgAV/HSP cohort (n = 159), the clinical characteristics of fever and renal involvement were more common in our COVID-19-associated pediatric IgAV/HSP cohort (fever, 30% versus 5%, respectively [P < 0.001]; renal involvement, 43.3% versus 17.6%, respectively [P = 0.002]). Recovery without treatment and complete recovery were each less frequent among our COVID-19-associated pediatric IgAV/HSP patients compared to the pre-pandemic pediatric IgAV/HSP cohort (recovery without treatment, 10% versus 39%, respectively [P = 0.002]; complete recovery, 86.7% versus 99.4%, respectively [P = 0.002]).

CONCLUSION

This is the largest cohort of children with COVID-19-associated vasculitis (excluding MIS-C) studied to date. Our findings suggest that children with COVID-19-associated IgAV/HSP experience a more severe disease course compared to pediatric IgAV/HSP patients before the pandemic.

COVID-19 Associated Vasculitis Confirmed by the Tissues RT-PCR: A Case Series Report

Background: Several cases of skin and central nervous system vasculopathy associated with COVID-19 in children have been published, but the information is rather limited. Our study aimed to describe these cases of vasculitis associated with COVID-19 in children. Methods: In the retrospective-prospective case series study we included information regarding four children with COVID-19-associated vasculitis. In every case, we had a morphological description and the etiology was confirmed via real-time polymerase chain reaction during a tissue biopsy. Results: The most involved systems were skin (4/4), respiratory (3/4), cardiovascular (2/4), nervous (1/4), eye (1/4), kidney (1/4), and inner year (1/4). All patients had increased inflammatory markers and thrombotic parameters (D-dimer). No patient met the criteria for multisystem inflammatory syndrome in children. Two patients met polyarteritis nodosa criteria, one met Henoch–Schonlein purpura criteria, and one met unclassified vasculitis criteria. All patients were treated with systemic glucocorticosteroids (two-pulse therapy). Non-biologic DMARDs were prescribed in all cases; 1/4 patients (25%) was treated with intravenous immunoglobuline, and 3/4 (75%) were treated with biologics (etanercept, tocilizumab, and adalimumab). Conclusions: Vasculitis associated with COVID-19 could be a life-threatening condition; SARS-CoV-2 might be a new trigger or etiological agent for vasculitis and other immune-mediated diseases. Further research and collection of similar cases are required.

Classification and epidemiology of vasculitis: Emerging concepts

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

Changing face of non-infectious pediatric uveitis in the pre-pandemic and pandemic periods: a comparison study

OBJECTIVE

Our aim in this study was to reveal the clinical features of pediatric uveitis in the pandemic period and to compare it with the pre-pandemic era.

METHODS

This retrospective study included 187 children diagnosed with uveitis between the 11^th of March 2017 and the 11^th of March 2022. The patients were divided into two groups based on the date of diagnosis as follows; Group 1: Patients diagnosed in the pre-pandemic period (11^th March 2017-11^th March 2020); Group 2: Patients diagnosed in the pandemic period (12^th March 2020-11^th March 2022). Demographic data, characteristics of uveitis, underlying diseases, systemic treatment modalities, and complications were compared between the two groups.

RESULTS

A total of 187 (pre-pandemic 71, and pandemic 114) pediatric uveitis patients were recruited to the study. Fifty one percent (51%) of the patients were female. The number of patients diagnosed with uveitis increased approximately twice during the pandemic period compared to the pre-pandemic period. The frequency of anterior uveitis was found to be significantly higher in the pandemic period than in the pre-pandemic period (p = 0.037). It was mostly presented as symptomatic uveitis. There was a decrease in the diagnosis of JIA-related uveitis. ANA positivity increased in the pandemic period (p = 0.029). The response to treatment was better and the complication rate decreased in the pandemic period.

CONCLUSION

The present study involved a large number of pediatric patients with uveitis. There are some differences in the characteristics of pediatric uveitis cases comparing the pandemic period and the pre-pandemic period. This increased frequency and changing clinical features of pediatric uveitis seems to be a result of COVID-19 infection.

Rheuma nach COVID-19-Infektion oder Impfung

Sowohl nach COVID-Infektion als auch nach ein oder mehreren COVID-Impfungen können rheumatische Beschwerden beginnen. In beiden Fällen scheint der Mechanismus ähnlich zu sein und mit dem Coronavirus oder seinen spezifischen Folgen zusammenzuhängen. Zumeist wird von einer reaktiven Arthritis gesprochen, wenngleich die Bezeichnung COVID-19-assoziierte Arthritis für das Beschwerdebild eher zutreffen dürfte. In Relation zur Zahl der COVID-Infizierten und der COVID-geimpften ist die Zahl der Fälle, in denen es zu COVID-assoziierten Beschwerden kommt, außerordentlich gering und die Prognose scheint eher gut zu sein.

From Co-Infections to Autoimmune Disease via Hyperactivated Innate Immunity: COVID-19 Autoimmune Coagulopathies, Autoimmune Myocarditis and Multisystem Inflammatory Syndrome in Children

Neutrophilia and the production of neutrophil extracellular traps (NETs) are two of many measures of increased inflammation in severe COVID-19 that also accompany its autoimmune complications, including coagulopathies, myocarditis and multisystem inflammatory syndrome in children (MIS-C). This paper integrates currently disparate measures of innate hyperactivation in severe COVID-19 and its autoimmune complications, and relates these to SARS-CoV-2 activation of innate immunity. Aggregated data include activation of Toll-like receptors (TLRs), nucleotide-binding oligomerization domain (NOD) receptors, NOD leucine-rich repeat and pyrin-domain-containing receptors (NLRPs), retinoic acid-inducible gene I (RIG-I) and melanoma-differentiation-associated gene 5 (MDA-5). SARS-CoV-2 mainly activates the virus-associated innate receptors TLR3, TLR7, TLR8, NLRP3, RIG-1 and MDA-5. Severe COVID-19, however, is characterized by additional activation of TLR1, TLR2, TLR4, TLR5, TLR6, NOD1 and NOD2, which are primarily responsive to bacterial antigens. The innate activation patterns in autoimmune coagulopathies, myocarditis and Kawasaki disease, or MIS-C, mimic those of severe COVID-19 rather than SARS-CoV-2 alone suggesting that autoimmunity follows combined SARS-CoV-2-bacterial infections. Viral and bacterial receptors are known to synergize to produce the increased inflammation required to support autoimmune disease pathology. Additional studies demonstrate that anti-bacterial antibodies are also required to account for known autoantigen targets in COVID-19 autoimmune complications.

Viral Infections May Be Associated with Henoch-Schönlein Purpura

Henoch-Schönlein purpura or IgA vasculitis is the most common type of pediatric vasculitis that may affect adults as well. It is classified as a type of small-vessel vasculitis. It can cause cutaneous and systemic symptoms with a minority of patients developing kidney failure. Little is known about the specific pathophysiology of this disorder, except that it is believed to occur in individuals with abnormally glycosylated IgA1. Serum aberrant IgA1 may form large antigen-antibody complexes which, due to a defective clearance, are able to deposit in the small vessels of the skin, kidney, gut, and joints. A variety of factors, including infectious agents, drugs, and vaccines, have been identified as potential triggers. The majority of cases are preceded by upper respiratory tract infections, and seasonal variations suggest a link with many pathogens. The etiologic agent most frequently associated with IgA vasculitis historically have been group A β-hemolytic streptococcus and common respiratory tract viruses. However, during the current coronavirus pandemic, SARS-CoV-2 infection was identified as a main trigger factor. In addition, IgA vasculitis has been observed following COVID-19 immunization. This review provides insights into the state of the art on the relationship between viral infections, viral vaccines, and Henoch-Schönlein purpura.

Patients Without a Rheumatic Disease Diagnosis in a Pediatric Rheumatology Unit: Retrospective Analysis and Comparison Between Pre-pandemic and Pandemic Periods

OBJECTIVE

Children with suspicious complaints of rheumatic diseases are generally referred to a pediatric rheumatologist. We aimed to evaluate the profile of patients referred to the pediatric rheumatology unit and were not diagnosed with a rheumatic disease and to assess the impact of the coronavirus disease-2019 pandemic on referral complaints.

MATERIALS AND METHODS

All new outpatients who applied to the pediatric rheumatology department between March 2019 and February 2021 and were not diagnosed with rheumatic disease were included. We also compared the frequency of admission symptoms during the pre-pandemic (March 2019-February 2020) and pandemic periods (March 2020-February 2021).

RESULTS

A total of 1089 patients without a rheumatic disease diagnosis (568 female, 52.2%; median age 10.0 years) were included in this study. The most common complaint for referral was prolonged or recurrent fevers (13.4%) followed by anti-nuclear antibody positivity (13.1%), arthralgia (13.0%), skin findings (7.5%), and the presence of heterozygous mutations in the Mediterranean fever gene (6.9%). During the pandemic year, the number of patients referred for back pain increased significantly (P = .028). A total of 682 of 1089 patients were consulted from other departments in our center (62.6%). Of these, the most frequent consultation request was from general pediatrics (43.6%). The rheumatic disease was excluded in 11.3% of the patients.

CONCLUSION

Prolonged or recurrent fever and anti-nuclear antibody positivity were the most frequent complaints of referrals to a pediatric rheumatology unit in patients who did not have a rheumatic disease. The rate of back pain was more common in children during the pandemic period.

The Absence of Permanent Sensorineural Hearing Loss in a Cohort of Children with SARS-CoV-2 Infection and the Importance of Performing the Audiological "Work-Up"

BACKGROUND

Currently, the novel coronavirus (SARS-CoV-2) causes an acute respiratory illness named COVID-19 and is a controversial risk factor for hearing loss (HL). Herein, we aim to describe the associated symptoms and to evaluate hearing function in the COVID-19 pediatric population.

METHODS

A retrospective cross-sectional observational study was carried out on 37 children who contracted COVID-19 infection with no previous audio-vestibular disorders. Clinical data on the infections were collected, and an audiological assessment of all affected children was performed by using different diagnostic protocols according to their age.

RESULTS

Fever, upper respiratory and gastrointestinal manifestations were common presentations of infection. Audiological function was normal in 30 (81.08%) children, while 7 children showed an increased hearing threshold: 6 (16.21%) had transient conductive hearing loss (CHL) due to middle ear effusion and normalized at the follow-up and 1 had sensorineural hearing loss (SNHL). A single child was affected by bilateral SNHL (2.7%); however, he underwent a complete audiological work-up leading to a diagnosis of genetic HL due to a MYO6 gene mutation which is causative of progressive or late onset SNHL.

CONCLUSIONS

HL needs to be considered among the manifestations of COVID-19 in children, nevertheless, we found cases of transient CHL. The onset of HL during or following COVID-19 infection does not eliminate the indication for maintaining audiological surveillance and audiological work-ups, including genetic diagnosis, to avoid the risk of mistaking other causes of HL.

IgA vasculitis update: Epidemiology, pathogenesis, and biomarkers

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

Epidemiology and clinical evolution of non-multisystem inflammatory syndrome (MIS-C) dermatological lesions in pediatric patients affected by SARS-CoV-2 infection: A systematic review of the literature

COVID-19 can present with a range of skin manifestations, some of which specific of the pediatric age. The aim of this systematic literature review was to determine the type, prevalence, time of onset, and evolution of cutaneous manifestations associated with COVID-19 in newborns, children, and adolescents, after excluding multisystem inflammatory syndrome in children (MIS-C). PubMed, Tripdatabase, ClinicalTrials, and Cochrane Library databases were searched using an ad hoc string for case reports/series and observational studies, published between December 2019 and February 2022. Study quality was assessed using the STROBE and CARE tools. Seventy-three (49 case reports/series and 24 studies) out of 26,545 identified articles were included in the analysis. Dermatological lesions were highly heterogeneous for clinical presentation, time of onset, and association with other COVID-19 manifestations. Overall, they mainly affected the acral portions, and typically presented a favorable outcome. Pseudo-chilblains were the most common.

CONCLUSIONS

Mucocutaneous manifestations could be the only/predominant and early manifestation of COVID-19 that could precede other more severe manifestations by days or weeks. Therefore, physicians of all disciplines should be familiar with them.

WHAT IS KNOWN

• A variety of cutaneous manifestations have been reported in association with COVID-19. • Urticaria, maculopapular, or vesicular rashes can occur at any age, while chilblains and erythema multiforme are more common in children and young patients.

WHAT IS NEW

• Skin lesions related to SARS-CoV-2 infection often show a peculiar acral distribution. • Mucocutaneous lesions of various type may be the only/predominant manifestation of COVID-19; they could present in paucisymptomatic and severely ill patients and occur at different stages of the disease.

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.