Pediatric vasculitis

Single-cell RNA sequencing: an emerging tool revealing dysregulated innate and adaptive immune response at single cell level in kawasaki disease

INTRODUCTION

Kawasaki disease [KD] is a systemic disorder characterized by acute febrile illness due to widespread medium-vessel vasculitis, mainly affecting children. Despite the ongoing advanced research into the disease pathophysiology and molecular mechanisms, the exact etiopathogenesis of KD is still an enigma. Recently, single-cell RNA sequencing [scRNA-seq], has been utilized to elucidate the pathophysiology of KD at a resolution higher than that of previous methods.

AREA COVERED

In the present article, we re-emphasize the pivotal role of this high-resolution technique, scRNA-seq, in the characterization of immune cell transcriptomic profile and signaling/response pathways in KD and explore the diagnostic, prognostic, and therapeutic potential of this new technique in KD. Using combinations of the search phrases 'KD, scRNA-seq, CAA, childhood vasculitis' a literature search was carried out on Scopus, Google Scholar, PubMed until the beginning of 2024.

EXPERT OPINION

scRNA-seq presents a transformative tool for dissecting KD at the cellular level. By revealing rare cell populations, gene expression alterations, and disease-specific pathways, scRNA-seq aids in understanding the intricacies of KD pathogenesis. This review will provide new insights into pathogenesis of KD and the field of applications of single-cell RNA sequencing in personalized therapeutics for KD in the future.

Rare insights: Atypical MRI features of juvenile SLE

Patients with systemic lupus erythematosus (SLE) frequently show symptoms of central nervous system involvement, termed neuropsychiatric SLE (NPSLE). Central nervous system (CNS) vasculitis is one of the neurological pathologies seen in CNS lupus. Patients with NPSLE typically present with nonspecific symptoms such as headache and cognitive impairment. Due to a lack of specific neuroradiological findings, diagnosis and management of such patients remain a big challenge. We report a 5-year-old girl who presented with fever and headache as the only neurological symptoms. Magnetic resonance imaging (MRI) of the brain showed focal grey and white matter lesions, suggestive of inflammatory or demyelinating ethology. Even though MR imaging findings may not be diagnostic of CNS lupus vasculitis, the study is routinely performed as a part of initial evaluation in patients with juvenile SLE showing neurological signs and symptoms.

The Diagnostic Role of Skin Manifestations in Rheumatic Diseases in Children: A Critical Review of Paediatric Vasculitis

Skin lesions are frequently observed in children with rheumatic diseases, particularly in conditions such as IgA vasculitis (IgAV) and Kawasaki disease (KD). In paediatric vasculitis, the presence of skin lesions serves as an early indicator, emphasising the importance of timely diagnosis to prevent complications, such as cardiac or renal involvement. Conversely, autoinflammatory disorders like juvenile systemic lupus erythematosus (SLE) and juvenile dermatomyositis (DM) may manifest with cutaneous manifestations either at the onset of disease or during its progression. Identifying these skin lesions prior to the appearance of systemic symptoms offers an opportunity for early diagnosis and treatment, which has a positive influence on the outcomes. Additionally, it is noteworthy that specific rheumatological conditions, such as acute rheumatic fever (ARF) or oligoarticular or polyarticular forms of juvenile idiopathic arthritis (JIA), may exhibit occasional, but significant skin involvement, which is strongly correlated with an unfavourable prognosis. The assessment of skin is important in the holist approach to assessing patients for potentially systemic/multisystem disorder and helps distinguish discrete conditions.

Multiresistant Kawasaki Disease in a Young Infant with Giant Aneurysms Growing Fast

BACKGROUND

Kawasaki disease (KD) is a type of vasculitis in which giant coronary artery aneurysms (CAAs) can occur. There are no specific guidelines for managing giant CAAs that develop quickly and are at risk of rupture. Regarding cardiovascular drugs, only beta-blockers are formally recommended in the acute phase of KD.

CASE PRESENTATION

A 6-month-old male patient with multiresistant Kawasaki disease and giant CAAs that continued to enlarge after controlling systemic inflammation was examined. The patient required three doses of intravenous immunoglobulin, methylprednisolone pulses, and anakinra and infliximab to normalize systemic inflammation. Due to the rapid increment of aneurysms' dimensions and the risk of rupture, we introduced anticoagulant therapy and propranolol plus captopril, and titration doses were introduced according to a tolerated decrease in heart rate and arterial pressure. CAAs increment stabilized and slowly reduced their dimensions.

CONCLUSIONS

The authors describe an atypical case of multiresistant KD with giant rapidly increasing CAAs even after controlling systemic inflammation. The introduction of a beta-blocker and an angiotensin-converting enzyme (ACE) inhibitor was demonstrated to be useful for stabilizing giant CAAs growth and reducing the potential risk of rupture.

Relationship between ocular manifestations, laboratory findings, echocardiographic findings, and intravenous immunoglobulin resistance in Kawasaki disease

BACKGROUND

This study investigates the incidence of ocular involvement in Kawasaki disease (KD) and evaluates the relationship between ocular manifestations, laboratory findings, echocardiographic findings, and intravenous immunoglobulin (IVIG) resistance.

METHODS

We conducted a cross-sectional study with 58 KD patients from June 2021 to March 2023. For all patients, a complete ophthalmologic examination and echocardiography were performed in the acute phase before starting the treatment. We analyzed the age, sex, mean of white blood cell (WBC) count, platelet count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), echocardiographic findings and IVIG responses for all patients and compared the group with ocular involvement with the group without involvement.

RESULTS

The incidence of bilateral acute conjunctivitis was 70.7%, while that of acute uveitis was 30%. Patients with uveitis had significantly higher rates of Coronary artery dilatation and IVIG resistance, as well as higher mean levels of WBC, platelet, and CRP compared to those without uveitis. (P < 0.05). Additionally, the age of patients with uveitis involvement was lower than those without involvement. No significant relationships existed between ESR, AST, or ALT values and uveitis (P > 0.05). Furthermore, no significant correlations existed between any examined items and acute bilateral conjunctivitis.

CONCLUSION

Uveitis in KD is significantly associated with coronary artery dilatation, IVIG resistance, higher WBC count, platelet count, and CRP level.

Rare Case of Abdominal Aortic and Multiple Visceral Aneurysms in a Pediatric Patient With PIK3CA Mutation and Vasculitis

Abdominal aortic aneurysms (AAA) are most commonly observed in elderly male patients and are particularly rare in children. Among the pediatric population, they are usually diagnosed in the context of connective tissue disorders, genetic mutations, or vasculitis. The same is true of visceral arteries aneurysms. This case report describes the staged management of an 11-year-old patient presenting PIK3CA mutation and a 5.8 cm infrarenal AAA associated with bilateral common iliac arteries and multiple visceral aneurysms, the largest observed in the superior mesenteric artery (SMA = 3.2 cm). After careful evaluation, decision was made to first approach the most life-threatening lesion (the infrarenal AAA due to the large diameter) and the remaining aneurysms in secondary procedures, with special attention to the SMA aneurysm. The patient underwent a staged repair, with the first phase consisting of an aortobi-iliac graft with the distal anastomosis made at the left common iliac artery and right external iliac artery. The right hypogastric artery was ligated. The second procedure consisted of SMA aneurysm repair with a plication technique, as 7 branches were visualized coming off the aneurysm sac. Postoperative pathology analysis of the aortic and SMA aneurysms sac revealed vasculitis with a mixed inflammatory pattern and a COL3A1 gene heterozygote variant. He is currently in his 18th month after the last surgical intervention, receiving immunomodulatory therapy, with a planned follow-up by the interdisciplinary team to monitor the medications' side effects and the diameter of the remaining visceral aneurysms.

Anti-LAMP-2 Antibody Seropositivity in Children with Primary Systemic Vasculitis Affecting Medium- and Large-Sized Vessels

Chronic primary systemic vasculitis (PSV) comprises a group of heterogeneous diseases that are broadly classified by affected blood vessel size, clinical traits and the presence (or absence) of anti-neutrophil cytoplasmic antibodies (ANCA) against proteinase 3 (PR3) and myeloperoxidase (MPO). In small vessel vasculitis (SVV), ANCA are not present in all patients, and they are rarely detected in patients with vasculitis involving medium (MVV) and large (LVV) blood vessels. Some studies have demonstrated that lysosome-associated membrane protein-2 (LAMP-2/CD107b) is a target of ANCA in SVV, but its presence and prognostic value in childhood MVV and LVV is not known. This study utilized retrospective sera and clinical data obtained from 90 children and adolescents with chronic PSV affecting small (SVV, n = 53), medium (MVV, n = 16), and large (LVV, n = 21) blood vessels. LAMP-2-ANCA were measured in time-of-diagnosis sera using a custom electrochemiluminescence assay. The threshold for seropositivity was established in a comparator cohort of patients with systemic autoinflammatory disease. The proportion of LAMP-2-ANCA-seropositive individuals and sera concentrations of LAMP-2-ANCA were assessed for associations with overall and organ-specific disease activity at diagnosis and one-year follow up. This study demonstrated a greater time-of-diagnosis prevalence and sera concentration of LAMP-2-ANCA in MVV (52.9% seropositive) and LVV (76.2%) compared to SVV (45.3%). Further, LAMP-2-ANCA-seropositive individuals had significantly lower overall, but not organ-specific, disease activity at diagnosis. This did not, however, result in a greater reduction in disease activity or the likelihood of achieving inactive disease one-year after diagnosis. The results of this study demonstrate particularly high prevalence and concentration of LAMP-2-ANCA in chronic PSV that affects large blood vessels and is seronegative for traditional ANCA. Our findings invite reconsideration of roles for autoantigens other than MPO and PR3 in pediatric vasculitis, particularly in medium- and large-sized blood vessels.

A case of ANCA-associated vasculitis in a 16-year-old female following SARS-COV-2 infection and a systematic review of the literature

BACKGROUND

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare form of vasculitis in children. SARS-CoV-2, the virus that causes COVID-19 infection, seems to trigger autoimmunity and new-onset autoimmune disease in pediatric and adult patients. We present a case of new-onset AAV following COVID-19 infection in an adolescent patient, and we review the literature of AAV following COVID-19 infection.

CASE PRESENTATION

An adolescent female with a history of asthma was diagnosed with mild COVID-19 infection and subsequently developed persistent cough, wheezing, hearing loss, arthralgias, and rash. Her imaging and laboratory workup showed pulmonary nodules and cavitary lesions, elevated inflammatory markers, negative infectious testing, and positive ANCA. She was treated with glucocorticoids, rituximab, and mycophenolate mofetil. At six-month follow-up, she had improvement in her symptoms, pulmonary function tests, imaging findings, and laboratory markers.

CONCLUSIONS

We report the second case of new-onset anti-PR3, C-ANCA vasculitis and the fourth case of pediatric-onset AAV following COVID-19 infection. A systematic review of the literature found 6 cases of new-onset AAV in adults after COVID-19 infection. Pediatric and adult patients who develop AAV post COVID-19 infection have few, if any, comorbidities, and show marked radiographic and symptomatic improvement after treatment. There is increasing evidence for COVID-19-induced autoimmunity in children and our case highlights the importance of considering AAV in a child following a recent COVID-19 infection because timely treatment may improve clinical outcomes.

Unusual interventional treatment of a complex calcified coronary artery lesion in a child with Kawasaki disease: a case report

Background

Kawasaki disease (KD) is a medium vessel vasculitis occurring in children, as yet of undetermined aetiology. KD can lead to severe complications such as coronary artery aneurysms, thrombosis, and sudden death. Monitoring of coronary anomalies is an important issue in the early phase of the disease, and their follow-up is based on different imaging methods. The interventional treatment of these coronary anomalies, which is often complex, is a therapeutic challenge.

Case summary

We are reporting the case of a four-year-old child who presented KD which was complicated by coronary aneurysm of the proximal left anterior descending artery and ectasia of the right coronary artery (RCA). These lesions progressively calcified and resulted at the age of 13 in chronic occlusion of the RCA. After confirmation of myocardial viability and myocardial ischaemia, a complex angioplasty guided by intracoronary imaging was performed using rotational atherectomy, a cutting balloon, and a high pressure balloon. The control coronary angiography performed 1 year later revealed two false aneurysm on the RCA at the angioplasty site, which were successfully treated with a covered stent.

Discussion

This case report describes the challenges of treating coronary artery abnormalities such as calcified coronary lesions in children with KD. The coronary intervention of these lesions remains complex and may lead to coronary rupture. We highlight the advantage of using intracoronary imaging in the management of these calcified lesions for successful revascularization, and to assess the complications of percutaneous coronary intervention.

Neonatal medium-sized vessel vasculitis: A rare case report

Vasculitis is a rare disorder during the neonatal period. We present a term male neonate of consanguineous parents and birthweight of 4 030 g who presented at 11 days of life with an evolving skin rash. There was no history of drug exposure in the neonate except for routine care. On day 7 of life, multiple erythematous plaques with necrotic or pustular centres appeared. There were no signs of mucosal involvement or sepsis and laboratory findings were normal. Skin biopsy revealed small and intermediate vessel vasculitis. At follow-up 2 weeks after discharge from the hospital, the skin lesions persisted, and at age 2 months, the patient presented with features of severe pneumonia and subsequently died. Vasculitis was reported as the cause of death on postmortem biopsy.

Gut Microbiota Dysbiosis in Childhood Vasculitis: A Perspective Comparative Pilot Study

Kawasaki disease (KD) and Henoch–Schönlein purpura (HSP) are the most frequent vasculitis in childhood. For both, a multifactorial mechanism has been hypothesised, with an abnormal immune response in genetically predisposed children. Gut microbiota (GM) alterations might trigger the hyperimmune reaction. Our aim was to explore the GM in KD and compare it with the GM of HSP and febrile children. Children diagnosed with KD, HSP and non-KD febrile illness (F) were enrolled. GM was profiled by 16S rRNA gene sequencing and compared with the profiles of healthy children from previous studies. We enrolled 13 KD, 10 HSP and 12 F children. Their GM significantly differed from controls, with an overall reduction in the relative abundance of beneficial taxa belonging to the Ruminococcaceae and Lachnospiraceae families. Potential KD and HSP signatures were identified, including smaller amounts of Dialister in the former, and Clostridium and Akkermansia in the latter. Notably, the GM structures of KD, HSP and F patients stratified by abdominal involvement, with more severe dysbiosis in those suffering from intestinal symptoms. This is the first study analysing GM in a mostly Caucasian cohort of KD and HSP children. Our data could open up new opportunities for childhood vasculitis treatment.

Lumbar swelling and migrating edema in 3- and 4-year-old boys

Henoch-Schönlein purpura is the most common systemic vasculitis in children, characterized by IgA deposits in small vessels. The etiology is unknown, but Henoch-Schönlein purpura typically follows an upper respiratory infection, or less frequently other infective or chemical triggers. The classic tetrad of symptoms includes palpable purpura (mandatory criterion), arthralgias, abdominal pain, and renal involvement. However, the cutaneous rash of Henoch-Schönlein purpura is not the presenting sign in approximately one-quarter of patients. Moreover, the other typical manifestations can present isolated or nuanced; for that reason, a prompt diagnosis may be challenging. Other clinical findings such as subcutaneous edema in hands, ankles, and feet, are quite common at pediatric Henoch-Schönlein purpura onset. Edema occurring in other locations (i.e facial and genital swelling), is uncommon, but can be a helpful additional clinical sign of Henoch-Schönlein purpura. To our knowledge, only two cases of lumbar swelling as Henoch-Schönlein purpura presentation signs have been described in literature so far.

Pediatric uveitis: Role of the pediatrician

The challenges of childhood uveitis lie in the varied spectrum of its clinical presentation, the often asymptomatic nature of disease, and the evolving nature of the phenotype alongside normal physiological development. These issues can lead to delayed diagnosis which can cause significant morbidity and severe visual impairment. The most common ocular complications include cataracts, band keratopathy, glaucoma, and macular oedema, and the various associated systemic disorders can also result in extra-ophthalmic morbidity. Pediatricians have an important role to play. Their awareness of the various presentations and etiologies of uveitis in children afford the opportunity of prompt diagnosis before complications arise. Juvenile Idiopathic Arthritis (JIA) is one of the most common associated disorders seen in childhood uveitis, but there is a need to recognize other causes. In this review, different causes of uveitis are explored, including infections, autoimmune and autoinflammatory disease. As treatment is often informed by etiology, pediatricians can ensure early ophthalmological referral for children with inflammatory disease at risk of uveitis and can support management decisions for children with uveitis and possible underling multi-system inflammatory disease, thus reducing the risk of the development of irreversible sequelae.

Immunoglobulin A vasculitis without purpura in an elderly female patient: a case report

Immunoglobulin A (IgA) vasculitis mainly affects the joints, skin, kidneys, and gastrointestinal tract; however, purpura is an essential diagnostic criterion. Here, we report an unusual case of IgA vasculitis without purpura in an elderly woman. A 76-year-old woman was admitted to our hospital complaining of diarrhea and abdominal pain. No skin rash, purpura, jaundice, or peripheral lymphadenopathy was observed. Endoscopy of the small intestine revealed severe mucosal sloughing in the duodenum, and a biopsy specimen showed severe erosive duodenitis. A decrease in coagulation factor XIII (FXIII) activity was also observed during laboratory blood tests. IgA immunostaining revealed granular IgA deposition on the walls of the interstitial small blood vessels. Although the patient showed no purpura or renal involvement, a diagnosis of IgA vasculitis was made based on the histopathology findings from biopsies. The administration of purified FXIII concentrate improved her symptoms immediately and facilitated regeneration of the duodenal villi. When gastroenterologists encounter severe erosive duodenitis or inflammation of the small intestine, IgA vasculitis should be listed as part of the differential diagnosis even without purpura and/or renal involvement. For a definitive diagnosis, measurement of FXIII and IgA immunostaining using duodenal biopsy specimens should be performed actively.

Systematic review of childhood-onset polyarteritis nodosa and DADA2

BACKGROUND

Diagnosis of childhood polyarteritis nodosa (PAN) has become challenging after the definition of deficiency of adenosine deaminase 2 (DADA2). We aimed to define the differential features of pediatric PAN and DADA2 patients in our center and in the literature.

METHODS

The charts of pediatric PAN and DADA2 patients followed at the Pediatric Rheumatology Unit of Hacettepe University between 2010-2020 were analyzed. A systematic literature review was conducted for articles regarding pediatric PAN or DADA2.

RESULTS

Thirty-four pediatric PAN and 18 pediatric DADA2 patients were included. The age at onset was younger, parental consanguinity, livedo reticularis, neurologic involvement (especially strokes), lymphopenia, and hypogammaglobulinemia were more frequent, while thrombocytosis and panniculitis were less frequent in DADA2 patients. The primary treatment was anti-tumor necrosis factor (anti-TNF) in DADA2. For induction treatment, all systemic PAN patients received corticosteroids, and cyclophosphamide (n=11) or mycophenolate mofetil (MMF) (n = 3). Cyclophosphamide was replaced with MMF in nine once remission was confirmed with PVAS. In the literature, 28 articles describing 613 pediatric PAN patients and 26 articles describing 207 pediatric DADA2 patients were identified. Neurologic, gastrointestinal, and cardiac involvements were more frequent in DADA2, while constitutional symptoms and testis involvement were more common in PAN.

CONCLUSION

In a child with PAN-like phenotype, DADA2 should be considered in the presence of young age at disease onset, parental consanguinity, strokes, lymphopenia, and lack of thrombocytosis during active disease. Anti-TNF treatment is indicated for vasculitic DADA2. Cyclophosphamide could be switched to MMF when remission is confirmed with PVAS in severe PAN.

Clinical presentations and long term prognosis of childhood onset polyarteritis nodosa in single centre of Korea

Childhood-onset polyarteritis nodosa (PAN) is a rare and systemic necrotising vasculitis in children affecting small- to medium-sized arteries. To date, there have been only a few reports because of its rarity. Thus, we aimed to investigate the clinical manifestations, laboratory findings, treatment, and long-term outcomes in patients with childhood-onset PAN and to evaluate the usefulness of the paediatric vasculitis activity score (PVAS). We retrospectively analysed the data of nine patients with childhood-onset PAN from March 2003 to February 2020. The median ages at symptom onset, diagnosis, and follow-up duration were 7.6 (3–17.5), 7.7 (3.5–17.6), and 7.0 (1.6–16.3) years, respectively. All patients had constitutional symptoms and skin manifestations, while five exhibited Raynaud’s phenomenon. Organ involvement was observed in one patient. The median PVAS at diagnosis was 7 (range: 2–32). Prednisolone was initially used for induction in all patients, and other drugs were added in cases refractory to prednisolone. All patients survived, but three patients with high PVAS at diagnosis experienced irreversible sequelae, including intracranial haemorrhage and digital amputation. In conclusion, early diagnosis and treatment may minimise sequelae in patients with childhood-onset PAN. This study suggests that high PVAS score at diagnosis may be associated with poor prognosis.

Kawasaki Disease in the Australian Population: An Australian Tertiary Hospital Experience

AIM

To describe the contemporary experience of Kawasaki Disease (KD) in a tertiary paediatric hospital.

METHODS

This was a retrospective analysis of admissions with suspected/confirmed KD to John Hunter Children's Hospital from 1 January 2015 to 31 December 2016, with follow-up. Patients were stratified into classical, incomplete, unlikely and uncertain KD cohorts based on the 2004 American Heart Association (AHA) guidelines.

RESULTS

Forty (40) patients had 45 admissions with suspected KD. Twenty-four (24) patients (60%) had complete and incomplete KD. Twenty-nine per cent (29%) (7/24) were not diagnosed at presentation. Thirty per cent (30%) (12/40) were incompletely assessed according to the AHA pathway. Seventy-one per cent (71%) of KD patients (17/24) were treated with aspirin and intravenous immunoglobulin. The incidence was 22-26 per 100,000 in children less than 5 years during the study period, higher compared to prior data.

CONCLUSION

The diagnosis of KD remains challenging, with some children not diagnosed at the time of initial presentation. The increase in KD incidence is hypothesis generating and requires further investigation.

Pulmonary Manifestations of Systemic Vasculitis in Children

Vasculitides are defined according to the vessel size involved, and they tend to affect certain organ systems. Pulmonary involvement is rare in the common childhood vasculitides, such as Kawasaki disease, IgA vasculitis (Henoch Schonlein purpura). On the other hand, lung involvement is common in a rare pediatric vasculitis, granulomatosis with polyangiitis (GPA) (Wegener granulomatosis), where respiratory system findings are common. A criterion in the Ankara 2008 classification criteria for GPA is the presence of nodules, cavities, or fixed infiltrates. The adult data suggest that rituximab may be an alternative to cyclophosphamide in induction treatment.

Case Report: Systemic Small-Vessel Vasculitis in an Adolescent With Active Ulcerative Colitis

Introduction: Small-vessel vasculitis (SVV) is a rare immunological disease that affects arterioles, capillaries and venules. It causes purpura, but can also manifest in other organs, including the gastrointestinal tract. SVV and inflammatory bowel disease (IBD) co-occur more frequently than would be expected by chance. Case description: A 16-year-old girl, who had been diagnosed with ulcerative colitis (UC) 2 years earlier at a general hospital, developed purpura, progressive abdominal pain with frequent bloody diarrhea and frontotemporal headache and swelling while on azathioprine and mesalamine maintenance therapy. Serology was positive for perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) without antiprotease- or myeloperoixidase antibodies. Endoscopy revealed active left-sided UC and atypical ulcerations in the ascending colon. Biopsies of these ulcerations and of affected skin revealed leukocytoclastic vasculitis. Initially this was interpreted as an extraintestinal manifestation of UC that would subside when remission was induced, consequently infliximab was started. Over the next 3 weeks she developed severe burning pain in her right lower leg that progressed to a foot drop with numbness and the purpura progressed to bullous lesions. The diagnosis was adjusted to ANCA-associated vasculitis with involvement of skin, bowel and peripheral nerves. Infliximab was discontinued and induction treatment with high-dose prednisolone and cyclophosphamide was given until remission of SVV and UC was achieved. Subsequently, infliximab induction and maintenance was re-introduced in combination with methotrexate. Remission has been maintained successfully for over 2 years now. The foot drop only partly resolved and necessitated the use of an orthosis. Conclusion: Pediatric patients with IBD who present with purpuric skin lesions and abdominal pain should be evaluated for systemic involvement of SVV, which includes endoscopic evaluation of the gastrointestinal tract. We discuss a practical approach to the diagnosis, evaluation and management of systemic SVV with a focus on prompt recognition and early aggressive therapy to improve outcome.

Inflammasomes and Childhood Autoimmune Diseases: A Review of Current Knowledge

Inflammasomes are multiprotein complexes capable of sensing pathogen-associated molecular patterns (PAMPs), danger-associated molecular patterns (DAMPs), and cellular perturbations. Upon stimulation, the inflammasomes activate the production of the pro-inflammatory cytokines IL-1β and IL-18 and induce gasdermin D-mediated pyroptosis. Dysregulated inflammasome signaling could lead to hyperinflammation in response to environmental triggers, thus contributing to the pathogenesis of childhood autoimmune/autoinflammatory diseases. In this review, we group childhood rheumatic diseases into the autoinflammation to autoimmunity spectrum and discuss about the involvement of inflammasomes in disease mechanisms. Genetic mutations in inflammasome components cause monogenic autoinflammatory diseases, while inflammasome-related genetic variants have been implicated in polygenic childhood rheumatic diseases. We highlight the reported associations of inflammasome signaling-related genetic polymorphisms/protein levels with pediatric autoimmune disease susceptibility and disease course. Furthermore, we discuss about the use of IL-1 receptor antagonist as an adjunctive therapy in several childhood autoimmune diseases, including macrophage activation syndrome (MAS) and multisystem inflammatory syndrome in children (MIS-C) related to COVID-19. A comprehensive multi-cohort comparison on inflammasome gene expression profile in different pediatric rheumatic diseases is needed to identify patient subsets that might benefit from the adjunctive therapy of IL-1β inhibitors.

Intravenous γ Globulin for Intractable Abdominal Pain due to IgA Vasculitis

IgA vasculitis (formerly known as Henoch–Schönlein purpura or anaphylactoid purpura) is a usually benign vasculitis that affects children of school age. The disease is characterized by the tetrad of palpable purpura, arthralgia/arthritis, abdominal pain, and hematuria. Treatment of IgA vasculitis is mainly supportive, with administration of simple analgesics. Corticosteroids have been shown to reduce and/or ameliorate the occurrence of abdominal pain which may be severe. We present two children with IgA vasculitis and severe abdominal pain despite corticosteroid administration, who responded promptly to intravenous γ globulin (IVIg) with complete resolution of their symptoms and review of the relevant medical literature. Given the toxicity and/or need for long-term administration of other second-line immunosuppressive therapies in corticosteroid-resistant IgA vasculitis, such as rituximab, cyclosporine, cyclophosphamide, azathioprine, or colchicine, we propose that IVIg may be a useful and safe treatment option, although randomized controlled clinical trials are needed in order to clarify its role in the treatment of abdominal pain in IgA vasculitis.

Initial manifestations and short term follow-up results of Henoch-Schönlein purpura in children: A report from two centers

OBJECTIVE:

This retrospective observational study aims to demonstrate initial signs and symptoms of Henoch-Schönlein purpura (HSP), search for risk factors for gastrointestinal and renal involvement and give short term follow-up results.

METHODS:

The files of newly diagnosed HSP patients from two pediatric rheumatology centers in the southeastern part of the country were retrospectively analyzed in this study. Demographic, clinical features and laboratory results were recorded from the files.

RESULTS:

The cohort consisted of 323 children (males: 53.6%, females: 46.4%). Median age at the time of diagnosis was 7.5 (1.8–17.3) years and the median duration of follow-up was six (3–22) months. The rash was present in all cases but was not the first symptom in 22.9% of the cases. Arthritis and abdominal pain before the development of rash were the initial symptoms in 11.8% and 11.1% of the cases, respectively. Other manifestations were subcutaneous edema (63.2%), arthralgia (57.6%), arthritis (27.6%), myalgia (17.6%), lethargy (10.2%), orchitis (7.5%) and fever (5.3%). Gastrointestinal involvement was seen in 53.3% and renal involvement in 23.5% of the cases. None of the patients developed renal impairment during the follow-up. Older age at diagnosis, necrotic rash, subcutaneous edema, abdominal pain, lethargy, myalgia, arthralgia and arthritis were significantly higher in patients with renal involvement, but none of the demographic, clinical and laboratory features was an independent risk factor for renal or gastrointestinal involvement.

CONCLUSION:

Abdominal pain, arthritis may be the first manifestation of HSP. Having constitutional symptoms, such as fever, myalgia and lethargy at the time of diagnosis, may be warning signs of a more aggressive course with gastrointestinal and renal involvement.

Correlation of gut microbial compositions to the development of Kawasaki disease vasculitis in children

Aim: Here, we hypothesize that dysbiotic gut microbiota might contribute to the development of Kawasaki disease (KD), a pediatric disease with unknown etiology. This is the second report on gut microbiota composition in KD patients. Materials & results: 16S amplicon sequencing was performed on fecal DNA samples and revealed predominance of bacterial pathogens, such as Fusobacterium, Neisseria, Shigella and Streptococcus, in the gut of KD patients, but absent or suppressed after immunoglobulin/antibiotics therapy. In addition, beneficial bacteria propagated after the therapy. Conclusion: We conclude that prevalence of Fusobacteria, Shigella and Streptococcus might contribute to KD pathogenesis.

IgA vasculitis (Henoch - Schönlein Purpura) as the first manifestation of juvenile Systemic Lupus Erythematosus: Case-control study and systematic review

Background

We have recognized 15 children with jSLE and the antecedent of IgA vasculitis (HSP). This association is not broadly present in the literature.

Aim

To know the age and gender distribution of children with IgA vasculitis (HSP), compare it to our IgA vasculitis (HSP) + jSLE cases, and identify prognostic factors to develop jSLE within our case series, IgA vasculitis (HSP) vs. IgA vasculitis (HSP) + jSLE.

Methods

A systematic review was carried out to know the age and gender distribution of children with IgA vasculitis (HSP). The information obtained plus data from 110 children with IgA vasculitis (HSP) from the Instituto Nacional de Pediatría were used to compare groups and identify prognostic factors. We performed a case-control study in patients < 18 years, consisting of 15 cases retrospectively identified with IgA vasculitis (HSP) + jSLE, and 110 IgA vasculitis (HSP) control subjects.

Results

The information of 12,819 IgA vasculitis (HSP) subjects from the systematic review and 110 IgA vasculitis (HSP) controls was obtained and compared to our 15 IgA vasculitis (HSP) + jSLE cases. The mean age of IgA vasculitis (HSP) was 7.1-years vs. 10.4-years of IgA vasculitis (HSP) + jSLE at the HSP diagnosis. Female to male ratio of IgA vasculitis (HSP) was 1:1.33 vs. 1:0.25 of IgA vasculitis (HSP) + jSLE. Patients with IgA vasculitis (HSP) + jSLE had lower levels of Hemoglobin (Hb) compared to patients with IgA vasculitis (HSP) 109 g/L vs. 141 g/L. For the development of jSLE, we found older age and lower levels of Hb as prognostic factors with OR [95% CI]: 1.37 [1.06, 1.89] and 5.39 [2.69, 15.25], respectively.

Conclusion

IgA vasculitis (HSP) + jSLE patients are older and have lower levels of Hb than patients with IgA vasculitis (HSP). It is necessary to confirm these findings through a prospective study.

National Trends in the Epidemiology and Resource Use for Henoch-Schönlein Purpura (IgA Vasculitis) Hospitalizations in the United States From 2006 to 2014

OBJECTIVES

We examined the trends in the rate of Henoch-Schönlein purpura (HSP) hospitalizations and the associated resource use among children in the United States from 2006 through 2014.

METHODS

Pediatric hospitalizations with HSP were identified by using International Classification of Diseases, Ninth Revision, code 287.0 from the National Inpatient Sample. HSP hospitalization rate was calculated by using the US population as the denominator. Resource use was determined by length of stay (LOS) and hospital cost. We used linear regression for trend analysis.

RESULTS

A total of 16 865 HSP hospitalizations were identified, and the HSP hospitalization rate varied by age, sex, and race. The overall HSP hospitalization rate was 2.4 per 100 000 children, and there was no trend during the study period. LOS remained stable at 2.8 days, but inflation-adjusted hospital cost increased from $2802.20 in 2006 to $3254.70 in 2014 (P < .001).

CONCLUSIONS

HSP hospitalization rate in the United States remained stable from 2006 to 2014. Despite no increase in LOS, inflation-adjusted hospital cost increased. Further studies are needed to identify the drivers of increased hospitalization cost and to develop cost-effective management strategies.

The peculiarities of Kawasaki disease at the extremes of age: Two case reports

RATIONALE

Extremes of age is an important risk factor for the development of coronary arteries aneurysms (CAAs) associated to Kawasaki disease (KD) along with male gender, prolonged fever and a delay in diagnosis or treatment.

PATIENT CONCERNS

We report two cases of KD in the extremes of age, a 5-month-old male infant and a 9-year-old child in order to underline the features of this disorder outside the typical age range of 1 to 4 years. The 5-month-old male was admitted in our clinic for generalized polymorphous exanthema and fever for approximately 7 days. The laboratory test pointed out leukocytosis and increased inflammatory biomarkers. The 9-year-old male child was admitted in our clinic for fever and submandibular adenopathy. The onset was approximately 5 days before the admission with a sudden development of unilateral, painless, submandibular lymphadenopathy for which the ENT specialist recommended antibiotics and nonsteroid anti-inflammatory drugs. In the 2nd day of admission, he presented severe desquamation of hands and soles.

DIAGNOSIS

Both cases were diagnosed with KD. The echocardiography showed no cardiac impairment in the infant, while in the older patient it revealed mild dilation of the left coronary artery.

INTERVENTIONS

Both patients received intravenously immunoglobulin and pulsed methylprednisolone.

OUTCOMES

The evolution was favorable in both cases, but in the infant, the C-reactive protein levels persisted mildly elevated for approximately 2 months after the diagnosis.

LESSONS

The peculiarities of KD in the extremes of age are related to a higher frequency of incomplete features and an increased incidence of coronary artery lesions resulting in a delay of the diagnosis, and subsequent poorer outcomes.

An Autopsy Case of a 5-Year-Old Child with Acute Pancreatitis Caused by Eosinophilic Granulomatosis with Polyangiitis-like Necrotizing Vasculitis

In children, acute pancreatitis has been reported in IgA vasculitis, Kawasaki disease, systemic lupus erythematosus-associated vasculitis, and juvenile dermatomyositis-associated vasculitis. However, its frequency in these vasculitides has been shown to be low. In other childhood-onset vasculitides, acute pancreatitis is seldom reported. The patient was a 5-year-old Japanese boy who suddenly presented with gastrointestinal (GI) bleeding. Therapy with antiulcer drugs successfully stopped bleeding, but subsequently, high fever, leukocytosis, and hypoxia appeared. He died 12 days after he presented with GI bleeding. An autopsy unexpectedly revealed that necrotizing vasculitis with marked eosinophilic and histiocytic infiltration of the pancreas led to acute pancreatitis, and gastric ulcer with eosinophilic infiltration was shown to be the origin of GI bleeding. In addition, eosinophilic infiltration was found in the small intestine, lungs, and bone marrow. Necrotizing vasculitis with eosinophilic and histiocytic infiltration of the pancreas, eosinophilic infiltration of the airway wall, and eosinophilic gastroenteritis with gastric ulcer were histologically confirmed, suggesting that the present case may be an early stage of eosinophilic granulomatosis with polyangiitis- (EGPA-) like vasculitis. To our knowledge, this might be the first reported case of EGPA-like vasculitis presenting with acute pancreatitis in a child.

Tales from the Night:: Emergency MR Imaging in Pediatric Patients after Hours

Overnight in-house radiology has rapidly become an important part of contemporary practice models, and is increasingly the norm in pediatric radiology. MR imaging is an indispensable first-line and problem-solving tool in the pediatric population. This has led to increasingly complex MR imaging being performed "after hours" on pediatric patients. This article reviews the factors that have led to widespread overnight subspecialty radiology and the associated challenges for overnight radiologists, and provides an overview of up-to-date imaging techniques and imaging findings of the most common indications for emergent MR imaging in the pediatric population.

The clinical spectrum of Henoch-Schönlein purpura in children: a single-center study

OBJECTIVES

Henoch-Schönlein purpura (HSP) is the most common vasculitis of children. The aim of this study is to evaluate the demographic and clinic findings of patients with HSP and also to determine predictive factors for assessing the development of gastrointestinal system (GIS) and renal involvement.

METHODS

This study was performed prospectively among children with HSP who are under 18 years of age and being followed-up in the Pediatric Rheumatology Unit of Health Sciences University Kanuni Sultan Süleyman Training and Research Hospital between January 2016 and January 2018.

RESULTS

A total of 265 patients, 137 boys (51.7%) and 128 girls (48.3%), were involved to the study. The mean ± standard deviation of age at the diagnosis was 7.5 ± 3.2. The most common disease onset season was spring (31.7%). The rate of arthritis, GIS involvement, and renal involvement were 54%, 51.3%, and 29.1%, respectively. GIS bleeding was more frequent in males than females (p = 0.007). Boys over 7 years of age had significantly more common GIS bleeding (p = 0.04). Intussusception, relapse, and serious GIS involvement requiring hospitalization and steroid treatment were highly associated with severe renal involvement.

CONCLUSIONS

We demonstrated that patients suffering intussusception, relapse, and serious GIS involvement or requiring hospitalization and steroid treatment had tendency to present with severe renal involvement. Therefore, these patients should be followed up carefully for not overlooking renal involvement of HSP.

Approach to the Child with Hematuria

The causes of macroscopic and microscopic hematuria overlap; both are often caused by urinary tract infections or urethral/bladder irritation. Coexistent hypertension and proteinuria should prompt investigation for glomerular disease. The most common glomerulonephritis in children is postinfectious glomerulonephritis. In most patients, and especially with isolated microscopic hematuria, the diagnostic workup reveals no clear underlying cause. In those cases whereby a diagnosis is made, the most common causes of persistent microscopic hematuria are thin basement membrane nephropathy, immunoglobulin A nephropathy, or idiopathic hypercalciuria. Treatment and long-term prognosis varies with the underlying disease.

Successful treatment of hemorrhagic bullous Henoch-Schonlein purpura with intravenous immunoglobulins

Henoch-Schonlein purpura (HSP) is the most common systemic vasculitis in childhood. There is no consensus about the management for isolated cutaneous manifestations in HSP. We describe a case of HSP presenting with severe skin lesions that did not respond to standard therapy with corticosteroids. The 11-year-old child was treated with intravenous immunoglobulins, which induced rapid and persistent resolution of symptomatology.

Childhood- versus Adult-Onset Polyarteritis Nodosa Results from the French Vasculitis Study Group Registry

OBJECTIVE

To investigate differences between childhood (cPAN)- and adult-onset polyarteritis nodosa (aPAN) patients.

METHODS

cPAN patients' clinical findings at onset and outcomes were compared to those of aPAN patients from the French Vasculitis Study Group registry matched for year of enrollment and initial systemic versus cutaneous disease. Their information on medications, disease activity and damage were collected. Kaplan-Meier relapse-free survival curves and the log-rank test were used to analyze cPAN versus aPAN differences for predefined outcomes.

RESULTS

Twenty-one children with systemic and 13 with cutaneous PAN were compared with 84 systemic- and 27 cutaneous-matched aPAN patients. Median follow-up exceeded 5 years for both groups. At study entry, mononeuritis multiplex was less frequent in systemic cPAN than systemic aPAN (P = 0.04), and purpura and myalgias were less frequent in cutaneous cPAN than cutaneous aPAN (P < 0.03). During follow-up, systemic cPAN relapsed more often than matched systemic aPAN (P < 0.0001), while relapse rates were similar for cutaneous disease (P > 0.05). Mostly minor relapses, predominantly involving the skin, occurred in all 4 groups. At last visit, damage accrual was comparable for cPAN and aPAN patients, but fewer systemic cPAN patients were treatment-free (15% versus 42%; P = 0.03). Two (6%) cPAN and 8 (7%) aPAN patients died.

CONCLUSION

Systemic PAN is equally severe in children and adults and carries a higher risk of relapse. The main cutaneous PAN features seem not to be influenced by age at disease onset.

Kawasaki Disease

Kawasaki disease (KD) is an acute-onset systemic vasculitis of medium-sized vessels that mostly affects infants and toddlers. Globally, it is the most common form of childhood primary vasculitis. Delayed diagnosis and treatment results in coronary artery aneurysms in up to 25% of all affected individuals. Thus, KD is the most common acquired heart disease in developed countries. Here, the current understanding of clinical presentations, pathophysiological concepts, disease-associated complications, and available pharmaceutical treatment is provided and discussed in the context of available literature.

Cutaneous Manifestations of Small-Vessel Leukocytoclastic Vasculitides in Childhood

In childhood, cutaneous small-vessel vasculitides include Henoch-Schönlein syndrome, a systemic vasculitis, and Finkelstein-Seidlmayer syndrome, a skin-limited vasculitis. Both Henoch-Schönlein and Finkelstein-Seidlmayer syndromes are seen more frequently in white or Asian compared with black children and occur especially in winter and spring with a male-to-female ratio of approximately 2:1. In everyday clinical practice, both conditions are diagnosed on clinical grounds without histological confirmation. The characteristic cutaneous hallmarks of Henoch-Schönlein syndrome include a purpuric rash in all and a subcutaneous edema in approximately every second case, which are often preceded by non-specific red or pink macular elements that mimic a non-itching urticarial rash. Recent data point out that Henoch-Schönlein children often present further cutaneous findings such as Köbnerization, Rumpel-Leede capillary fragility phenomenon, and blistering eruptions. Children with Finkelstein-Seidlmayer syndrome are usually ≤24 months of age and not ill-appearing. They present with (a) large, round, red to purpuric plaques (often with a targetoid appearance) predominantly over the cheeks, ears, and extremities and (b) often tender non-pitting edema of the distal extremities, ears, and face (without pruritus). Both in Henoch-Schönlein syndrome and Finkelstein-Seidlmayer syndrome, there is often scrotal involvement. The cutaneous findings remit without sequelae within 2 months in Henoch-Schönlein and 3 weeks in Finkelstein-Seidlmayer syndrome.

Kawasaki disease and vasculitis associated with immunization

The etiology and pathogenesis of Kawasaki disease (KD) remain poorly understood. Among the diverse infectious and environmental factors examined to be triggers for, or be associated with, KD, are immunizations. In this report, we first describe the case of a Caucasian girl who presented with classic KD shortly after receiving her routine 4 months vaccination series. Prior published case reports and large epidemiological studies, which explore potential associations between immunization and KD and other vasculitides, are then comprehensively reviewed. The methodologic challenges that complicate analysis in this area are also considered.

Histopathology of Cutaneous Inflammatory Disorders in Children

Inflammatory dermatoses encompass a variety of histologic patterns that affect different portions of the skin. In spongiotic, psoriasiform, lichenoid, pityriasiform, and blistering disorders, there are predominately epidermal and junctional activities with variable superficial dermal inflammation. Hypersensitivity reactions can show either epidermal or mostly dermal changes depending on whether the exposure of the exogenous allergen occurs through an external or internal route, respectively. Exceptions include erythema multiforme and Stevens-Johnson syndrome/toxic epidermal necrolysis, where the etiology is often due to infection or ingested medications, but the histologic features are almost exclusively confined to the epidermis and dermoepidermal junction. Autoimmune disorders are unique in that lesions typically incorporate a mixture of epidermal and dermal inflammatory patterns with periadnexal inflammation, while the vast majority of vasculitis/vasculopathy and alopecia have changes limited to only the vessels and hair follicles, respectively. It is critical to recognize that a relatively limited number of histologic patterns are seen in a large array of clinical entities. Therefore, clinicopathologic correlation and careful examination of histologic details are of the utmost importance when evaluating skin biopsies for inflammatory disorders.

Incomplete Refractory Kawasaki Disease in an Infant-A Case Report and a Review of the Literature

Kawasaki disease (KD) is a febrile vasculitis, which is commonly defined by fever and at least four specific clinical symptoms. Incomplete KD is defined by suggestive echocardiographic findings with an incomplete clinical picture. Refractory KD is diagnosed in patients resistant to intravenous immunoglobulin (IVIG). We report the case of a 6-month-old male infant admitted to our clinic for persistent fever and onset of a generalized polymorphous rash, accompanied by high fever, rhinorrhea, and cough for the past 7 days. The laboratory tests, on the day of admission, revealed leukocytosis with neutrophilia, anemia, thrombocytosis, hypernatremia, hypoalbuminemia, elevated C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Echocardiography showed dilation of the left anterior descending coronary artery (LAD). Based on all these findings, we established the diagnosis of KD, and we initiated IVIG and intravenous pulsed methylprednisolone, with an initial favorable outcome. However, the symptoms reappeared, and we administered a second higher single dose of IVIG, but without any clinical improvement. Moreover, the laboratory parameters and echocardiographic findings worsened. We reinitiated a longer course of intravenous methylprednisolone in a smaller dose, which had a favorable impact on the clinical, laboratory, and echocardiographic parameters. Multiple uncertainties exist related to the management of refractory KD despite the wide spectrum of therapeutic options that have been proposed. Our case demonstrates that in patients refractory to aggressive initial therapy, low or moderate doses of steroid given daily may be helpful.

Childhood Vasculitis

The term vasculitis covers heterogeneous disorders that share the presence of inflammation of blood vessel walls. Immune cell infiltrates can vary significantly and involve granulocytes or mononuclear cells. Vasculitis can be a symptom of other underlying disorders or the underlying cause of organ specific or systemic disease. Classification of childhood vasculitis is based on clinic, the size of predominantly affected vessels, and the histopathology of inflammatory infiltrates. Timely and accurate diagnosis and (where necessary) treatment initiation determine disease progression and outcomes. In light of new developments and the identification of autoinflammatory conditions with vasculitis, new classification tools may be discussed.

Late Relapse of Henoch-Schönlein Purpura in an Adolescent Presenting as Severe Gastroduodenitis

Henoch-Schönlein purpura is a systemic vasculitis, commonly affecting children. Gastrointestinal manifestations are observed in 50-75% of patients; it is well known they may occur before skin lesions in about 20% of cases during the first vasculitic episode. Relapses occur in about one third of patients, typically within 4 months from the initial presentation and with milder symptoms. We report the case of a 17-year old girl with an atypical relapse of Henoch-Schönlein purpura, presenting with acute abdominal symptoms 5 years after the first episode. Esophagogastroduodenoscopy showed duodenal multiple hyperemic and hemorrhagic lesions. To our knowledge this is the first case of hemorrhagic-erosive duodenitis representing a relapse of Henoch-Schönlein purpura occurring several years after the initial episode. Duodenojejunal inflammation should be considered as primary manifestation of Henoch-Schönlein purpura, not only during the first episode, but also in relapses. Endoscopy can be helpful for differential diagnosis, especially in patients with atypical manifestations. Further studies are needed to evaluate risk factors for Henoch-Schönlein purpura recurrence and the possible role of fecal calprotectin as an early marker for gastrointestinal involvement.

Cerebral Vasculitis in Henoch-Schönlein Purpura: A Case Report

Henoch-Schönlein purpura is a common form of systemic small vessel vasculitis in childhood. Although headache and behavioral changes have been described in a significant proportion of children with Henoch-Schönlein purpura, severe neurological complications are rare. In this article, we report a case of central vasculitis in a four-year-old boy who presented with hemiplegia and aphasia. The treatment options for cerebral vasculitis of Henoch-Schönlein purpura are numerous but controversial in pediatric patients. Our patient was successfully treated by pulse methylprednisolone and pulse cyclophosphamide. The patient was followed-up for four years without any sequel.