Etanercept as adjunctive treatment for acute Kawasaki disease: study design and rationale

Exploring the association between serum Vitamin D levels and the development of coronary artery lesions in Kawasaki disease - a systematic review

BACKGROUND

Kawasaki Disease (KD) involves arterial inflammation, primarily affecting the coronary arteries and leading to coronary artery lesions. Recent advancements in understanding the immunomodulatory roles of vitamin D have prompted investigations into the potential correlation between serum vitamin D levels and the risk of coronary artery lesions (CAL) in KD. This review aims to explore this association.

METHODS

A systematic search utilizing relevant keywords related to Kawasaki disease and coronary artery lesions was conducted across four databases (PubMed, Embase, Scopus, and Web of Science). The quality of the incorporated studies was assessed utilizing the Newcastle-Ottawa Scale. The study protocol is registered in PROSPERO under the registry code CRD42024493204.

RESULTS

In a review of five studies involving 442 KD patients and 594 healthy controls, KD patients generally had lower serum vitamin D levels compared to controls, with mixed findings on the association with coronary artery lesions and IVIG resistance. While three studies supported lower vitamin D in KD, one showed no significant difference. Regarding CAL, one study found lower vitamin D, another found higher levels associated with CAL, and two found no significant difference.

CONCLUSIONS

Overall, the evidence is inconclusive, but there's a trend suggesting potential benefits of sufficient vitamin D levels in Kawasaki disease rather than evidence refuting any association with clinical outcomes.

Etanercept with IVIg for acute Kawasaki disease: a long-term follow-up on the EATAK trial

BACKGROUND

The Etanercept as Adjunctive Treatment for Acute Kawasaki Disease, a phase-3 clinical trial, showed that etanercept reduced the prevalence of IVIg resistance in acute Kawasaki disease. In patients who presented with coronary artery involvement, it reduced the maximal size and short-term progression of coronary artery dilation. Following up with this patient group, we evaluated the potential long-term benefit of etanercept for coronary disease.

METHODS

Patients were followed for at least 1 year after the trial. The size of dilated arteries (z-score ≥ 2.5) was measured at each follow-up visit. The z-score and size change from baseline were evaluated at each visit and compared between patients who received etanercept versus placebo at the initial trial.

RESULTS

Forty patients who received etanercept (22) or placebo (18) in the Etanercept as Adjunctive Treatment for Acute Kawasaki Disease trial were included. All patients showed a persistent decrease in coronary artery size measurement: 23.3 versus 5.9% at the 6-month visit, 24 versus 13.1% at the 1-year visit, and 20.8 versus 19.3% at the ≥ 2-year visit for etanercept or placebo, respectively, with similar results for decrease in coronary artery z-scores. In a multivariate analysis, correcting for patients' growth, a greater size reduction for patients on the etanercept arm versus placebo was proved significant for the 6-month (p = 0.005) and the 1-year visits (p = 0.019) with a similar end outcome at the ≥ 2-year visit.

DISCUSSION

Primary adjunctive therapy with etanercept for children with acute Kawasaki disease does not change the end outcome of coronary artery disease but may promote earlier resolution of artery dilation.

Inflammation in Coronary Microvascular Dysfunction

Chronic low-grade inflammation is involved in coronary atherosclerosis, presenting multiple clinical manifestations ranging from asymptomatic to stable angina, acute coronary syndrome, heart failure and sudden cardiac death. Coronary microvasculature consists of vessels with a diameter less than 500 μm, whose potential structural and functional abnormalities can lead to inappropriate dilatation and an inability to meet the required myocardium oxygen demands. This review focuses on the pathogenesis of coronary microvascular dysfunction and the capability of non-invasive screening methods to detect the phenomenon. Anti-inflammatory agents, such as statins and immunomodulators, including anakinra, tocilizumab, and tumor necrosis factor-alpha inhibitors, have been assessed recently and may constitute additional or alternative treatment approaches to reduce cardiovascular events in atherosclerotic heart disease characterized by coronary microvascular dysfunction.

TNF-α blockers for the treatment of Kawasaki disease in children

BACKGROUND

Kawasaki disease (KD) is an acute inflammatory vasculitis (inflammation of the blood vessels) that mainly affects children between six months and five years of age. The vasculitis primarily impacts medium-sized blood vessels, especially in the coronary arteries. In most children, intravenous immunoglobulin (IVIG) and aspirin therapy rapidly reduce inflammatory markers, fever, and other clinical symptoms. However, approximately 15% to 20% of children receiving the initial IVIG infusion show persistent or recurrent fever and are classified as IVIG-resistant. Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine that plays an important role in host defence against infections and in immune responses. Several studies have established that blocking TNF-α is critical for obtaining anti-inflammatory effects in children with KD, thus, there is a need to identify benefits and risks of TNF-α blockers for the treatment of KD.

OBJECTIVES

To evaluate the efficacy and safety of using TNF-α blockers (i.e. infliximab and etanercept) to treat children with Kawasaki disease.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases, the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials register to 19 September 2018. We also undertook reference checking of grey literature.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared TNF-α blockers (i.e. infliximab and etanercept) to placebo or other drugs (including retreatment with IVIG) in children with KD, reported in abstract or full-text.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the study selection criteria, assessed risk of bias and extracted data. When necessary, we contacted study authors for additional information. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included five trials from 14 reports, with a total of 494 participants. All included trials were individual RCTs that examined the effect of TNF-α blockers for KD.Five trials (with 494 participants) reported the incidence of treatment resistance. TNF-α blockers reduced the incidence of treatment resistance (TNF-α blocker intervention group 30/237, control group 58/257; risk ratio (RR) 0.57, 95% confidence interval (CI) 0.38 to 0.86; low-certainty evidence).Four trials reported the incidence of coronary artery abnormalities (CAAs). Three trials (with 270 participants) contributed data to the meta-analysis, since we could not get the data needed for the analysis from the fourth trial. There was no clear difference between groups in the incidence of CAAs (TNF-α blocker intervention group 8/125, control group 9/145; RR 1.18, 95% CI 0.45 to 3.12; low-certainty evidence).Three trials with 250 participants reported the adverse effect 'infusion reactions' after treatment initiation. The TNF-α blocker intervention decreased infusion reactions (TNF-α blocker intervention group 0/126, control group 15/124; RR 0.06, 95% CI 0.01 to 0.45; low-certainty evidence).Two trials with 227 participants reported the adverse effect 'infections' after treatment initiation. There was no clear difference between groups (TNF-α blocker intervention group 7/114, control group 10/113; RR 0.68, 95% CI 0.33 to 1.37; low-certainty evidence).One trial (with 31 participants) reported the adverse effect 'cutaneous reactions' (rash and contact dermatitis). There was no clear difference between the groups for incidence of rash (TNF-α blocker intervention group 2/16, control group 0/15; RR 4.71, 95% CI 0.24 to 90.69; very low-certainty evidence) or for incidence of contact dermatitis (TNF-α blocker intervention group 1/16, control group 3/15; RR 0.31, 95% CI 0.04 to 2.68; very low-certainty evidence).No trials reported other adverse effects such as injection site reactions, neutropenia, infections, demyelinating disease, heart failure, malignancy, and induction of autoimmunity.

AUTHORS' CONCLUSIONS

We found a limited number of RCTs examining the effect of TNF-α blockers for KD. In summary, low-certainty evidence indicates that TNF-α blockers have beneficial effects on treatment resistance and the adverse effect 'infusion reaction' after treatment initiation for KD when compared with no treatment or additional treatment with IVIG. Further research will add to the evidence base. Due to the small number of underpowered trials contributing to the analyses, the results presented should be treated with caution. Further large high quality trials with timing and type of TNF-α blockers used are needed to determine the effects of TNF-α blockers for KD.

Etanercept With IVIg for Acute Kawasaki Disease: A Randomized Controlled Trial

OBJECTIVES

Patients with Kawasaki disease can develop life-altering coronary arterial abnormalities, particularly in those resistant to intravenous immunoglobulin (IVIg) therapy. We tested the tumor necrosis factor α receptor antagonist etanercept for reducing both IVIg resistance and coronary artery (CA) disease progression.

METHODS

In a double-blind multicenter trial, patients with Kawasaki disease received either etanercept (0.8 mg/kg; n = 100) or placebo (n = 101) subcutaneously starting immediately after IVIg infusion. IVIg resistance was the primary outcome with prespecified subgroup analyses according to age, sex, and race. Secondary outcomes included echocardiographic CA measures within subgroups defined by coronary dilation (z score >2.5) at baseline. We used generalized estimating equations to analyze z score change and a prespecified algorithm for change in absolute diameters.

RESULTS

IVIg resistance occurred in 22% (placebo) and 13% (etanercept) of patients (P = .10). Etanercept reduced IVIg resistance in patients >1 year of age (P = .03). In the entire population, 46 (23%) had a coronary z score >2.5 at baseline. Etanercept reduced coronary z score change in those with and without baseline dilation (P = .04 and P = .001); no improvement occurred in the analogous placebo groups. Etanercept (n = 22) reduced dilation progression compared with placebo (n = 24) by algorithm in those with baseline dilation (P = .03). No difference in the safety profile occurred between etanercept and placebo.

CONCLUSIONS

Etanercept showed no significant benefit in IVIg resistance in the entire population. However, preplanned analyses showed benefit in patients >1 year. Importantly, etanercept appeared to ameliorate CA dilation, particularly in patients with baseline abnormalities.

[Pyrexia and hemoptysis for eight days in a school-age child]

A girl was diagnosed with intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD) due to pyrexia and hemoptysis for eight days. The girl was a school-age child with major clinical manifestations of pyrexia, skin rash, enlargement of bilateral cervical lymph nodes, conjunctival hyperaemia, red and cracked lips and strawberry-like tongue, followed by swelling of both hands and feet. Laboratory examination showed significant increases in white blood cell count, platelet count, C-reactive protein, erythrocyte sedimentation rate and liver enzymes, a significant reduction in albumin, and the presence of aseptic pyuria. After the first course of IVIG treatment, the girl still had recurrent pyrexia, with hemoptysis on day 2 after admission, and lung CT showed uneven luminance and patchy shadow. The symptoms were quickly alleviated after the second course of IVIG treatment combined with methylprednisolone and aspirin treatment. KD is a febrile disease characterized by multiple systemic vasculitis in childhood and can involve various organ systems such as the heart, lungs, kidneys and the nervous system. Therefore, it is necessary to carefully monitor and recognize the rare symptoms of KD, and early recognition of pulmonary complications of KD can avoid delay in diagnosis, prevent the development of more serious complications, and help with early treatment and disease recovery.

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.

Diagnosis, Treatment, and Long-Term Management of Kawasaki Disease: A Scientific Statement for Health Professionals From the American Heart Association

BACKGROUND

Kawasaki disease is an acute vasculitis of childhood that leads to coronary artery aneurysms in ≈25% of untreated cases. It has been reported worldwide and is the leading cause of acquired heart disease in children in developed countries.

METHODS AND RESULTS

To revise the previous American Heart Association guidelines, a multidisciplinary writing group of experts was convened to review and appraise available evidence and practice-based opinion, as well as to provide updated recommendations for diagnosis, treatment of the acute illness, and long-term management. Although the cause remains unknown, discussion sections highlight new insights into the epidemiology, genetics, pathogenesis, pathology, natural history, and long-term outcomes. Prompt diagnosis is essential, and an updated algorithm defines supplemental information to be used to assist the diagnosis when classic clinical criteria are incomplete. Although intravenous immune globulin is the mainstay of initial treatment, the role for additional primary therapy in selected patients is discussed. Approximately 10% to 20% of patients do not respond to initial intravenous immune globulin, and recommendations for additional therapies are provided. Careful initial management of evolving coronary artery abnormalities is essential, necessitating an increased frequency of assessments and escalation of thromboprophylaxis. Risk stratification for long-term management is based primarily on maximal coronary artery luminal dimensions, normalized as Z scores, and is calibrated to both past and current involvement. Patients with aneurysms require life-long and uninterrupted cardiology follow-up.

CONCLUSIONS

These recommendations provide updated and best evidence-based guidance to healthcare providers who diagnose and manage Kawasaki disease, but clinical decision making should be individualized to specific patient circumstances.

Kawasaki disease: etiopathogenesis and novel treatment strategies

INTRODUCTION

Kawasaki disease is an acute febrile systemic vasculitis that predominantly occurs in children below five years of age. Its etiopathogenesis is still not clear, but it is thought to be a complex interplay of genetic factors, infections and immunity. Areas covered: This review article discusses in detail Kawasaki disease, with particular emphasis on the recent updates on its pathogenesis and upcoming alternate treatment options. Though self-limiting in many cases, it can lead to severe complications like coronary artery aneurysms and thrombo-embolic occlusions, and hence requires early diagnosis and urgent attention to avoid them. Intravenous immunoglobulin (IVIG) with or without aspirin has remained the sole treatment option for these cases, but 10-15% cases develop resistance to this treatment. Expert commentary: There is a need to develop additional treatment strategies for children with Kawasaki disease. Targeting different steps of pathogenesis could provide us with alternate therapeutic options.

Coronary artery lesions and the increasing incidence of Kawasaki disease resistant to initial immunoglobulin

BACKGROUNDS

Kawasaki disease (KD) is a systemic vasculitis of childhood involving coronary arteries. Treatment for intractable cases at a higher risk of cardiac sequelae remains controversial.

METHODS

Clinical outcomes of KD patients diagnosed in Yamaguchi prefecture, Japan between 2003 and 2014 were analyzed using the medical records from all 14 hospitals covering the prefecture. The study included 1487 patients (male:female, 873:614; median age at diagnosis, 24months).

RESULTS

The proportion of initial intravenous immunoglobulin (IVIG)-resistant patients increased from 7% to 23% during this decade, although no patients died. Twenty-four patients developed coronary artery lesions (CALs) over one month after the KD onset. The incidence of CAL in patients who received corticosteroid during the disease course (10/37; 27.0%) was higher than that in those who did not (14/1450; 0.97%, p=2.0×10(-35)). Nine patients who responded to initial IVIG plus corticosteroids had no CAL. Conversely, IVIG-resistant patients with alternate corticosteroid therapy more frequently developed CAL than those without it (10/28; 35.7% vs. 5/194; 2.6%, p=8.9×10(-10)). Multivariate analyses indicated corticosteroid therapy (p<0.0001), hyperbilirubinemia (p=0.0010), and a longer number of days before treatment (p=0.0005) as risk factors associated with CAL over a month after onset. The odds ratio of corticosteroid use increased from 18.3 to 43.5 if the cases were limited to initial IVIG non-responders and corticosteroid free-IVIG responders.

CONCLUSIONS

IVIG-failure has recently increased. The incidence of CAL increased in intractable cases with prolonged corticosteroid use. Corticosteroid may not be alternate choice for IVIG-failure to reduce the risk of cardiac sequelae.

Kawasaki disease: pathophysiology, clinical manifestations, and management

Kawasaki Disease, a systemic vasculitis of unknown origin with specific predilection for the coronary arteries, is the most common cause of childhood-acquired heart disease in western countries. Despite its world-wide incidence, the pathophysiology of this enigmatic disease is still under investigation. Diagnosis is made on a clinical basis, with supportive laboratory evidence and imaging. Once identified, timely initiation of treatment is imperative in order to quell the inflammatory response and decrease the incidence of long-term sequelae, specifically coronary artery aneurysms. Finally, longitudinal follow-up should be implemented based on risk stratification and individualized to each patient.

DC-SIGN gene promoter variants and IVIG treatment response in Kawasaki disease

BACKGROUND

Genetic variants in the inhibiting FcγRIIB mediate anti-inflammatory responses and influence IVIG refractoriness (IVIG-R). However, these variants are rare in Asian and Hispanic populations so other genes in the pathway could be potentially involved. IVIG is ineffective in mice lacking SIGN-R1, a related molecule to human DC-SIGN. Further, DC-SIGN is a known receptor for sialylated Fc, the component responsible for the anti-inflammatory action of IVIG. Thus, we hypothesized that DC-SIGN would also be involved in the pathway of IVIG response in Kawasaki Disease (KD) patients.

FINDINGS

A case-control approach was performed to examine the differential distribution of five single nucleotide polymorphisms (SNPs) in DC-SIGN promoter with IVIG-R among White (158 vs. 62), Asian (64 vs. 12) and Hispanic (55 vs. 20) KD patients. Distinct differences in allele frequency distributions of several variants in the DC-SIGN promoter were observed in the three ethnic groups. Further, Asians with the major allele "A" in rs2287886 were more likely (OR = 1.76, p = 0.04) to be IVIG non-responder, but this allele is a minor allele in other two ethnic groups, where the association was not apparent.

CONCLUSIONS

DC-SIGN can potentially complement the role of FcγRIIB in the anti-inflammatory cascade involved in the IVIG response mechanism.

FcγR gene copy number in Kawasaki disease and intravenous immunoglobulin treatment response

OBJECTIVE

Kawasaki disease (KD), response to intravenous immunoglobulin (IVIG) therapy, and associated coronary artery disease progression have been associated with genetic polymorphisms in Fc gamma receptor (FcγR) genes. However, it is not known whether the existing gene copy number (GCN) variability relates to KD treatment response, susceptibility, or associated sequelae.

METHODS

The copy number of individuals with KD (n=510) and their family members (n=808) for three variable FcγRs was assessed using pyrosequencing. We performed the transmission disequilibrium test to examine the association of GCN for FcγRs (FcγR2C, FcγR3A, and FcγR3B) with susceptibility and used logistic regression models to determine its association with IVIG treatment outcomes.

RESULTS

FcγR2C and FcγR3B GCN were significantly associated with KD susceptibility. IVIG response was associated with GCN variations of FcγR3B in Whites and FcγR2C in Hispanics, and gene risk score based on single nucleotide polymorphism and GCN in FcγRs were significantly different between IVIG responders and nonresponders among Whites. We found no significant associations between coronary artery disease and any of the FcγR copy numbers.

CONCLUSION

GCN of FcγR2C and FcγR3B influences IVIG treatment response and predisposes individuals to KD, providing potential insights into understanding the mechanism of the FcγR gene family in the IVIG pathway.

Management of acute and refractory Kawasaki disease

Acute Kawasaki disease (KD) is treated with high-dose intravenous immunoglobulin (IVIG), which is proven to decrease the incidence of coronary artery aneurysms from 25% to less than 5%. Aspirin is also given, although the evidence base is less secure. There is increasing evidence for steroid therapy as adjunctive primary therapy with IVIG, especially in Asian children. Approximately 10-30% of patients fail to respond to the initial IVIG and are at increased risk of coronary artery aneurysms. The optimal treatment for IVIG-nonresponsive KD remains controversial. Management options include further dose(s) of IVIG, corticosteroids, TNF-α blockade, cyclosporin A, anti-IL-1 and anti-CD20 therapy. In this article, the authors review the current evidence for treatment of acute KD and discuss options for IVIG nonresponders.

[The role of immunosuppressive agents in Kawasaki disease: a discussion of two cases]

INTRODUCTION

Kawasaki disease (KD) is the most common cause of acquired heart disease in developed countries. Ten percent of patients with KD develop coronary aneurism. Ten percent of patients treated with intravenous immunoglobulin (IgIV) have persistent coronary dilatations, which sustains the search for new therapies. We describe 2 cases of refractory KD and discuss the therapeutic options.

CLINICAL REPORT

A 3-year-old child and a 3-month-old infant had refractory KD. Both were treated with IgIV and corticosteroids. They both had persistent fever and major coronary artery dilatation. The first patient received a treatment with acetyl-salicylic-acid (ACA) only. The second received an immuno-therapy with an anti-TNF-α agent. Fever and inflammatory symptoms disappeared within 12h in the second case. Coronary artery aneurisms worsened during the first month and then stabilized. The first child had fever and inflammatory symptoms for a longer duration, but coronary artery dilatations stabilized and disappeared with no additional treatment than ACA.

DISCUSSION AND CONCLUSION

TNF-α is known to be one of the inflammatory factors involved in KD disease. Anti-TNF-α agents have been tested in treatment of refractory KD. In one of the cases reported herein, this therapy was not effective on coronary artery aneurism. More studies are needed to define the optimal treatment of refractory KD.

Advances in the treatment of Kawasaki disease

PURPOSE OF REVIEW

Intravenous immunoglobulin (IVIG) and aspirin is the standard initial therapy in the treatment of Kawasaki disease. Some patients have persistent or recrudescent fever despite this therapy. Although there is no conclusive body of evidence defining the best second and third-line therapies for Kawasaki patients, there have been several recent studies published describing the results of these therapies.

RECENT FINDINGS

This review summarizes the current recommendations for the initial therapy and describes the second and third-line therapies studied in Japan and the United States. A recent study in a Japanese population of Kawasaki disease patients at high risk for IVIG resistance found that the group receiving steroids, in addition to IVIG and aspirin, had fewer coronary artery abnormalities than the group receiving IVIG and aspirin alone. Small studies of etanercept and infliximab have showed these TNF-alpha blockers to be well tolerated and effective in the resolution of fever.

SUMMARY

Although most practitioners in the USA use IVIG as a second-line therapy for those Kawasaki disease patients who have persistent or recrudescent fever, promising new therapies are under study. Infliximab and steroids are currently the two agents that have been most studied. However, larger studies and studies in genetically diverse populations are needed.

Natriuretic Peptides in Kawasaki Disease: the Myocardial Perspective

Making a diagnosis of Kawasaki disease with certainty may be challenging, especially since the recognition of cases with incomplete diagnostic criteria and its consequences. In order to build the diagnostic case in daily practice, clinicians rely on clinical criteria established over four decades ago, aided by non specific laboratory tests, and above all inspired by experience. We have recently studied the diagnostic value of N-terminal pro B-type natriuretic peptide to improve the diagnostic certainty of cases with complete or incomplete clinical criteria. Our working hypothesis was based on the fact that myocarditis is present in nearly all Kawasaki disease patients supported by histology data. In this paper, we review these facts and the myocardial perspective from the diagnostic and the mechanistic standpoints.

Increased percentages of tumor necrosis factor-alpha+/interferon-gamma+ T [corrected] lymphocytes and calprotectin+/tumor necrosis factor-alpha+ monocytes in patients with acute Kawasaki disease

In vivo exposure to microorganisms resident in the oral cavity is considered as a possible cause of Kawasaki disease (KD), and some epitopes derived from streptococci display homology with Factor H of Complement. Additionally, calprotectin, a major calcium binding protein released by neutrophils and activated monocytes, could be directly involved in endothelial damage occurring in KD. The aim of our study is to evaluate the percentages of IFN-gamma+ and/or TNF-alpha+ lymphocytes and double positive calprotectin/TNF-alpha monocytes (CD14+) after in vitro stimulation with streptococcal- and/or Factor H-derived peptides, in patients with acute KD. Peripheral Blood Mononuclear Cells (PBMCs) obtained from KD patients and febrile controls were stimulated in vitro with peptides. After culture, cells were collected, stained with fluorochrome-labelled monoclonal antibodies against CD3, CD14, calprotectin, IFN-gamma and TNF-alpha, and cytofluorimetric analyses were performed. Our results showed increased percentages of TNF-alpha+/IFN-gamma+ lymphocytes in KD patients in respect to controls when PBMCs were stimulated with streptococcal or Factor H-derived epitopes. In addition, also calprotectin+/TNF-alpha+ monocytes from KD patients were activated after PBMC in vitro stimulation. These findings lead us to speculate that some peptides, derived from oral streptococci and cross-reactive with the human Factor H of Complement, could induce lymphocyte and monocyte activation potentially involved in the pathogenesis of KD. Our results should be confirmed by further studies enrolling more patients and controls than those analyzed in our study.

Kawasaki disease

Kawasaki disease is a systemic vasculitis and the leading cause of acquired heart disease in North American and Japanese children. The epidemiology, cause, and clinical characteristics of this disease are reviewed. The diagnostic challenge of Kawasaki disease and its implications for coronary artery outcomes are discussed, as are the recommended treatment, ongoing treatment controversies, concerns associated with treatment resistance, and the importance of ongoing follow up.

The Molecular Biology and Treatment of Systemic Vasculitis in Children

Primary systemic vasculitides are rare in childhood but are associated with significant morbidity and mortality. The cause of the majority of vasculitides is unknown, although it is likely that a complex interaction between environmental factors, such as infections and inherited host responses, triggers the disease and determines the vasculitis phenotype. Several genetic polymorphisms in vasculitides have now been described, which may be relevant in terms of disease predisposition or development of disease complications. Treatment regimens continue to improve with the use of different immunosuppressive medications and newer therapeutic approaches such as biologic agents. This chapter reviews recent studies shedding light on the pathogenesis of vasculitis with emphasis on molecular biology where known, and summarizes current treatment strategies. We discuss new emerging challenges particularly with respect to the long-term cardiovascular morbidity for children with systemic vasculitis and emphasize the importance of future international multicenter collaborative studies to further increase and standardize the scientific base investigating and treating childhood vasculitis.

Kawasaki disease: an update on diagnosis and treatment

Kawasaki disease (KD) is an acute multi-system vasculitis syndrome of unknown etiology occurring mostly in infants and children younger than 5 years of age. In developed countries, it is the leading cause of acquired heart disease in children. However, KD remains a mysterious disease. Some viruses potentially causing the condition have been isolated, but the results have not been able to be reproduced. This article reviews and summarizes different aspects of KD and provides updated information on diagnosis and treatment. The supplementary criteria for incomplete presentation of KD patients suggested by the American Heart Association, treatment (including tumor necrosis factor-alpha antagonist, methylprednisolone pulse therapy, statins, plasma exchange, and cytotoxic agents) for those with intravenous immunoglobulin treatment failure, and other experiences are also included in this review.

Partial response to anakinra in life-threatening Henoch-Schönlein purpura: case report

Henoch-Schönlein purpura is one of the most common forms of systemic vasculitis of childhood. We report the response to anakinra, the interleukin-1 receptor antagonist, in a 9 year old girl without prior medical problems who developed life-threatening Henoch-Schönlein vasculitis that produced renal failure, pulmonary hemorrhage and vasculitis of the brain. Her response supports the theory that interleukin-1 may be an important mediator in this disease. Further study of interleukin-1 antagonists in severe Henoch-Schönlein purpura may be warranted.