Gastrointestinal presentation of Kawasaki disease: A red flag for severe disease?

Intestinal Microbiota Contributes to the Development of Cardiovascular Inflammation and Vasculitis in Mice

BACKGROUND

Alterations in the intestinal microbiota contribute to the pathogenesis of various cardiovascular disorders, but how they affect the development of Kawasaki disease (KD) an acute pediatric vasculitis, remains unclear.

METHODS

We used the Lactobacillus casei cell wall extract (LCWE) murine model of KD vasculitis to assess the contribution of the intestinal microbiota to the development of vascular inflammation. We evaluated the severity of vasculitis in microbiota-depleted mice. 16S rRNA gene sequencing was used to characterize the fecal microbiome composition of LCWE-injected mice. Some groups of mice were orally treated with selected live or pasteurized bacteria, short-chain fatty acids, or Amuc_1100, the Toll-like receptor 2 signaling outer membrane protein from Akkermansia muciniphila, and their impact on vasculitis development was assessed.

RESULTS

We report that depleting the gut microbiota reduces the development of cardiovascular inflammation in a murine model mimicking KD vasculitis. The development of cardiovascular lesions was associated with alterations in the intestinal microbiota composition and, notably, a decreased abundance of Akkermansia muciniphila and Faecalibacterium prausnitzii. Oral supplementation with either of these live or pasteurized individual bacteria or with short-chain fatty acids produced by them attenuated cardiovascular inflammation, as reflected by decreased local immune cell infiltrations. Treatment with Amuc_1100 also reduced the severity of vascular inflammation.

CONCLUSIONS

This study reveals an underappreciated gut microbiota-cardiovascular inflammation axis in KD vasculitis pathogenesis and identifies specific intestinal commensals that regulate vasculitis in mice by producing metabolites or via extracellular proteins capable of enhancing and supporting gut barrier function.

Gut Microbiota Alterations in Patients With Kawasaki Disease

The intestinal microbiota influences many host biological processes, including metabolism, intestinal barrier functions, and immune responses in the gut and distant organs. Alterations in its composition have been associated with the development of inflammatory disorders and cardiovascular diseases, including Kawasaki disease (KD). KD is an acute pediatric vasculitis of unknown etiology and the leading cause of acquired heart disease in children in the United States. The presence of gastrointestinal symptoms in the acute phase of KD has been associated with an increased risk of treatment resistance and the development of coronary artery aneurysms. Studies report alterations in fecal bacterial communities of patients with KD, characterized by the blooming of pathogenic bacteria and decreased relative abundance of short-chain fatty acid-producing bacteria. However, causality and functionality cannot be established from these observational patient cohorts of KD. This highlights the need for more advanced and rigorous studies to establish causality and functionality in both experimental models of KD vasculitis and patient cohorts. Here, we review the evidence linking an altered gut microbiota composition to the development of KD, assess the potential mechanisms involved in this process, and discuss the potential therapeutic value of these observations.

Clinical characteristics of Kawasaki disease with pulmonary radiographic abnormalities and its impact on the incidence of coronary artery lesions: a randomized retrospective cohort study

Objective

The aim of this study was to investigate the characteristics of Kawasaki disease (KD) in patients demonstrating pneumonia-like changes and pulmonary complications, as well as the subsequent impact on coronary artery lesions, by comparing them with those of KD patients with normal pulmonary imaging.

Method

From January 1, 2013 to October 1, 2022, this study included paediatric patients diagnosed with KD who were registered in the KD database at Yuying Children's Hospital affiliated with Wenzhou Medical University. Patients were divided into three distinct groups based on the presence and severity of abnormalities observed via lung imaging. We first compared the demographic and clinical characteristics across these groups. The imaging characteristics of KD patients with pneumonia-like changes and pulmonary complications were identified via chest radiography (x-ray) and chest computerized tomography (CT). Logistic regression models and stratified analyses were employed to further identify factors influencing coronary artery lesions (CALs).

Results

Among the 2,686 KD children admitted to our centre in recent years, 115 presented with pneumonia-like changes, 366 presented with pulmonary complications, and 495 presented with no evident abnormalities on chest radiographs. In KD patients with pneumonia-like changes, there were significant elevations in inflammatory markers including the C-reactive protein (CRP) (P = 0.011), white blood cell (WBC) (P = 0.027), NT-proBNP (P = 0.007), and D-dimer (D-D) (P = 0.002) levels. Imaging studies have frequently revealed bilateral lung infections, predominantly in the mid-lower lung fields. Bronchitis-related changes were the most common manifestation of pulmonary complications in KD patients. A significant difference was observed in the incidence of CALs among patients with pneumonia-like changes. After adjusting for confounding variables, patients with pneumonia-like changes had a greater likelihood of developing CALs, with an adjusted odds ratio (OR) of 1.94 [95% confidence interval (CI): 1.21, 3.11]. Similar findings were obtained through stratification and sensitivity analyses.

Conclusion

Patients diagnosed with KD who develop pneumonia-like changes and related pulmonary complications can be identified based on their clinical manifestations and imaging characteristics. Moreover, patients with KD and pneumonia-like changes had a significantly increased risk of developing CALs.

Nutrition-Associated Biomarkers in Predicting Intravenous Immunoglobulin Resistance and Coronary Artery Lesions in Kawasaki Disease: A Systematic Review and Meta-Analysis

Several studies explored the associations of pre-albumin (PA)/albumin (ALB) and ALB-combined indicators (prognostic nutrition index [PNI], albumin-to-globulin ratio [AGR], bilirubin-to-albumin [BAR], and C-reactive protein/albumin ratio [CAR]) with intravenous immunoglobulin (IVIG) resistance and coronary artery lesions (CALs) in Kawasaki disease (KD) patients. However, the results were controversial. A meta-analysis was conducted to reconfirm their associations and predictive performance. Databases of PubMed, EMBASE, and the Cochrane library were searched. The pooled standardized mean difference (SMD) or odds ratios (ORs) assessed the association, while the pooled area under the receiver operating characteristic curve (AUC) evaluated the predictive power. Ninety-four studies were included. Overall and subgroup meta-analyses demonstrated lower ALB and higher CAR were associated with IVIG resistance (ALB: SMD = -0.61; OR = 0.83; CAR: SMD = 1.47; OR = 1.69) and CALs (ALB: SMD = -0.56; OR = 0.92; CAR: SMD = 0.52). PNI was reduced in IVIG-resistant (SMD = -0.82) and coronary artery aneurysm (SMD = -0.18) patients in subgroup analysis and high PNI predicted the decreased risk of CALs in overall analysis (OR = 0.82). ALB, CAR, and PNI were a good or fair biomarker for differentiating IVIG-resistant (CALs) from IVIG-sensitive (non-CALs) patients (AUC > 0.6 or > 0.7). PA (SMD = -0.72) and BAR (SMD = 1.10) were differential in IVIG-resistant, but not in CAL patients compared with controls. AGR was not associated with CALs (p > 0.05). In conclusion, ALB, CAR, PNI, PA, and BAR may represent promising biomarkers for the prediction of IVIG resistance and CALs in KD patients.

The Central Role of Interleukin-1 Signalling in the Pathogenesis of Kawasaki Disease Vasculitis: Path to Translation

Kawasaki disease (KD) manifests as an acute febrile condition and systemic vasculitis, the etiology of which remains elusive. Primarily affecting children under 5 years of age, if untreated KD can lead to a significant risk of coronary artery aneurysms and subsequent long-term cardiovascular sequelae, including myocardial ischemia and myocardial infarction. Intravenous immunoglobulin therapy mitigates the risk of aneurysm formation, but a subset of patients exhibit resistance to this treatment, increasing the susceptibility of coronary artery lesions. Furthermore, the absence of a KD-specific diagnostic test or biomarkers complicates early detection and appropriate treatment. Experimental murine models of KD vasculitis have substantially improved our understanding of the disease pathophysiology, revealing the key roles of the NLRP3 inflammasome and interleukin-1 (IL-1) signalling pathway. This review aims to delineate the pathophysiologic findings of KD while summarising the findings for the emerging key role of IL-1β in its pathogenesis, derived from both human data and experimental murine models, and the translational potential of these findings for anti-IL-1 therapies for children with KD.

Beyond the Atypical: Gastrointestinal Manifestations in Kawasaki Disease

Kawasaki disease (KD) is an acute vasculitis mainly seen in children, with a specific risk for coronary artery involvement. Atypical symptoms can sometimes result in missed diagnoses, delaying necessary treatment and increasing the chances of serious cardiovascular complications. We report a case of a six-month-old previously healthy girl who had not been vaccinated. She presented with high fever, vomiting, and diarrhea for two weeks. The initial treatment for a suspected upper respiratory infection and later gastrointestinal issues created a diagnostic challenge. After many tests and scans over several weeks, a clear diagnosis was made only when an echocardiogram showed dilated coronary arteries and a dilated aortic root. She was then diagnosed with atypical KD and was given high doses of aspirin and intravenous immunoglobulins, resulting in substantial improvement in her condition. This case points out the difficulty in diagnosing KD in very young children, particularly when typical signs are missing. The delayed identification of KD led to serious complications, highlighting the importance of greater awareness among healthcare workers about atypical symptoms in infants. Quick action is vital to reduce the risk of severe cardiovascular consequences and to avoid delaying necessary treatment.

Analysis of the clinical characteristics of patients with Kawasaki disease complicated with cholestasis

BACKGROUND

To explore the clinical characteristics, related factors, and prognosis of Kawasaki disease (KD) combined with acute febrile cholestasis and improve the understanding of the liver complications of KD to avoid misdiagnosis and missed diagnosis.

METHODS

We retrospectively analyzed the demographic, clinical, and laboratory data of 1803 patients with KD between January 2019 and July 2023 in our hospital. Based on the presence of cholestasis, patients were divided into the cholestatic and control groups. Logistic regression analysis was performed for the statistically significant indicators between the two groups to examine the risk factors for KD with coronary artery abnormalities (CAA) and intravenous immunoglobulin (IVIG) unresponsiveness. Additionally, patients with KD and cholestasis were compared with patients with acute febrile cholestasis due to other causes during the same period.

RESULTS

Compared to the control group (n = 1720), patients in the cholestatic group (n = 83) were older, had higher levels of white blood cell count (WBC), C-reactive protein (CRP), D-dimer, N-terminal pro-brain natriuretic peptide (NT-proBNP), a shorter fever duration, and high incidences of IVIG unresponsiveness and CAA. KD was the leading cause of acute febrile cholestasis in children (72.6%). In the multivariate logistic regression analysis, younger age, cholestasis, hypoalbuminemia, and a high NT-proBNP level were risk factors for IVIG unresponsiveness, whereas male sex, longer fever duration before treatment, and high alanine aminotransferase (ALT), and CRP levels were risk factors for CAA.

CONCLUSION

KD with cholestasis was associated with a higher risk of IVIG unresponsiveness and coronary artery abnormalities. KD was the leading cause of acute febrile cholestasis in children. Attention to the possibility of KD is warranted in children with acute febrile cholestatic jaundice, especially if associated with elevated WBC, CRP, and D-dimer levels, or hypoalbuminemia.

Unraveling the gut: the pivotal role of intestinal mechanisms in Kawasaki disease pathogenesis

Kawasaki disease (KD), an acute systemic vasculitis that primarily affects children under 5 years of age, is the leading cause of acquired heart disease in this age group. Recent studies propose a novel perspective on KD's etiology, emphasizing the gastrointestinal (GI) tract, particularly the role of gut permeability. This review delves into how disruptions in gut barrier function trigger systemic inflammatory responses, exacerbate vascular inflammation, and contribute to coronary artery aneurysms. Evidence suggests that children with KD often exhibit increased gut permeability, leading to an imbalance in gut immunity and subsequent gut barrier damage. These changes impact vascular endothelial cells, promoting platelet aggregation and activation, thereby advancing severe vascular complications, including aneurysms. Additionally, this review highlights the correlation between GI symptoms and increased resistance to standard treatments like intravenous immunoglobulin (IVIG), indicating that GI involvement may predict therapeutic outcomes. Advocating for a new paradigm, this review calls for integrated research across gastroenterology, immunology, and cardiology to examine KD through the lens of GI health. The goal is to develop innovative therapeutic interventions targeting the intestinal barrier, potentially revolutionizing KD management and significantly improving patient outcomes.

Coronary Arteries Lesions in Kawasaki Disease: Risk Factors in an Italian Cohort

Background: Kawasaki disease (KD) is a systemic vasculitis of medium arteries, particularly involving coronary arteries. Coronary artery lesions (CALs) is the most serious complication in the acute stage, potentially leading to ischemic cardiomyopathy, myocardial infarction and sudden death. Environmental factors and genetic background contribute to individual susceptibility to develop CALs. The aim of this study was to define the risk factors for CALs in an Italian cohort. Methods: Data of KD patients from 10 Italian sites were registered into a REDCap database where demographic and clinical data, laboratory findings and coronary status were recorded. KD was diagnosed according to AHA definition. We used multiple logistic regression analysis to identify independent risk factors for CALs. Results: A total of 517 patients were enrolled, mainly Caucasians (83.6%). Presentation was complete in 321 patients (62.8%) and IVIG responsiveness in 360 (70%). CALs developed in 136/517 (26.31%). Gender, age, ethnicity, clinical presentation, fever duration, non-coronary cardiac events, Hb, albumin and CRP were significantly different between patients with and without CALs, while seasonality was not. Male gender, age < 18 months, Asian ethnicity, incomplete presentation and fever > 10 days were independent risk factors for CALs. Conclusions: Age younger than 18 months, incomplete KD and longer fever duration are risk factors for CALs. Asian ethnicity also represents a risk factor in our Italian Cohort.

The intestinal microbiota contributes to the development of immune-mediated cardiovascular inflammation and vasculitis in mice

Alterations in the intestinal microbiota contribute to the pathogenesis of various cardiovascular disorders, but how they affect the development of Kawasaki disease (KD), an acute pediatric vasculitis, remains unclear. We report that depleting the gut microbiota reduces the development of cardiovascular inflammation in a murine model mimicking KD vasculitis. The development of cardiovascular lesions was associated with alterations in the intestinal microbiota composition and, notably, a decreased abundance of Akkermansia muciniphila and Faecalibacterium prausnitzii. Oral supplementation with either of these live or pasteurized individual bacteria, or with short-chain fatty acids (SCFAs) produced by them, attenuated cardiovascular inflammation. Treatment with Amuc_1100, the TLR-2 signaling outer membrane protein from A. muciniphila , also decreased the severity of vascular inflammation. This study reveals an underappreciated gut microbiota-cardiovascular inflammation axis in KD vasculitis pathogenesis and identifies specific intestinal commensals that regulate vasculitis in mice by producing metabolites or via extracellular proteins acting on gut barrier function.

IN BRIEF

It remains unclear whether changes in the intestinal microbiota composition are involved in the development of cardiovascular lesions associated with Kawasaki disease (KD), an immune-mediated vasculitis. Jena et al. observe alterations in the intestinal microbiota composition of mice developing vasculitis, characterized by reduced A. muciniphila and F. prausnitzii . Oral supplementation with either of these bacteria, live or pasteurized, or with bacteria-produced short-chain fatty acids (SCFAs) or Amuc_1100, the TLR-2 signaling outer membrane protein of A. muciniphila , was sufficient to alleviate the development of cardiovascular lesions in mice by promoting intestinal barrier function.

HIGHLIGHTS

Absence or depletion of the microbiota decreases the severity of vasculitis in a murine model mimicking KD vasculitis. Supplementation of B. wadsworthia and B. fragilis promotes murine KD vasculitis. Decreased abundances of F. prausnitzii and A. muciniphila are associated with the development of cardiovascular lesions in mice. Supplementation with either live or pasteurized A. muciniphila and F. prausnitzii, or the TLR-2 signaling Amuc_1100, reduces the severity of vasculitis by promoting gut barrier function.

Kawasaki Disease With Acute Acalculous Cholecystitis: A Case Report

Acute acalculous cholecystitis (AAC) is an inflammatory disease of the gallbladder in the absence of gallstones. AAC has been linked to various systemic illnesses including Kawasaki disease (KD). We report a case of a five-year-old male brought to the emergency department (ED) with a history of fever and vomiting for four days. He was admitted as a case of KD. Then, we discovered that he had AAC, which was well managed by intravenous immunoglobulin (IVIG) as the fever subsided, C-reactive protein (CRP) decreased, and repeated abdominal ultrasound showed a decrease in gallbladder thickness without any evidence of coronary artery aneurysms.

Unusual Manifestations of Kawasaki Disease in the COVID Era: A Case Series and Review of the Literature

Kawasaki disease (KD) is an acute medium-vessel vasculitis, mainly affecting infants older than six months and children under five years. It predisposes to the development of coronary artery aneurysms and constitutes the leading cause of acquired heart disease in children. Its diagnosis is based on clinical criteria, namely, fever lasting for ≥ five days together with at least four of the five principal clinical features of the disease. Occasionally, children with KD present with fever, but they fulfill only some of the five principal criteria, and this is described as incomplete KD. Furthermore, "atypical" KD is a term that is usually used for cases that appear with rather unusual clinical manifestations, which complicate clinical judgment and may delay diagnosis and treatment. In this case series, we present four cases of KD with rather unusual clinical features: a five-year-old boy with lobar pneumonia, a six-year-old girl with orange-brown chromonychia appearing on the 10th day of the disease, a 2.5-month-old infant with prolonged fever and urinary tract infection, and an 18-month-old infant with refractory KD and high suspicion of multisystem inflammatory syndrome in children (MIS-C). A literature review on the unusual manifestations of atypical KD was performed to identify clinical findings that must alert the clinician to consider this clinical entity.

Kawasaki Disease Associated Acute Abdomen: Most Require No Surgery

Objective

To summarize the clinical features and treatment experiences of patients with Kawasaki disease (KD)-associated acute abdomen (KD-AA).

Methods

We conducted a retrospective case-control study of patients with KD-AA treated at our hospital between January 2006 and November 2022.

Results

Of the 917 children with KD, 43 (4.7%) presented with AA. Of these, 33 with complete information were included in the KD-AA group. Patients with KD-AA were significantly older, with higher neutrophil rate, C-reactive protein, procalcitonin, and alanine transaminase levels and lower hemoglobin, albumin, and serum sodium levels. Additionally, more patients with KD-AA presented with aseptic meningitis and KD shock syndrome than those with KD alone (all p<0.05). The two groups did not differ in the incidence of intravenous immunoglobulin (IVIG) resistance, incomplete KD, or coronary artery abnormalities. All patients received aspirin and IVIG therapy, with nine receiving a second dose of IVIG and 11 receiving corticosteroids. Only two patients with KD-AA underwent surgery, and the prognosis of all patients with KD-AA was good.

Conclusion

KD-AA should be suspected in febrile children with abdominal symptoms. Prompt diagnosis of KD-AA is important for early effective treatment to avoid unnecessary surgical harm. KD, complicated by acute abdomen, has a good prognosis.

Kawasaki disease, multisystem inflammatory syndrome in children, and adenoviral infection: a scoring system to guide differential diagnosis

Children with Kawasaki disease (KD), Multisystem Inflammatory Syndrome in Children (MIS-C), and Adenovirus infections (AI) of the upper respiratory tract show overlapping features. This study aims to develop a scoring system based on clinical or laboratory parameters to differentiate KD or MIS-C from AI patients. Ninety pediatric patients diagnosed with KD (n = 30), MIS-C (n = 26), and AI (n = 34) admitted to the Pediatric Emergency Unit of S.Orsola University Hospital in Bologna, Italy, from April 2018 to December 2021 were enrolled. Demographic, clinical, and laboratory data were recorded. A multivariable logistic regression analysis was performed, and a scoring system was subsequently developed. A simple model (clinical score), including five clinical parameters, and a complex model (clinic-lab score), resulting from the addition of one laboratory parameter, were developed and yielded 100% sensitivity and 80% specificity with a score ≥2 and 98.3% sensitivity and 83.3% specificity with a score ≥3, respectively, for MIS-C and KD diagnosis, as compared to AI.

CONCLUSION

This scoring system, intended for both outpatients and inpatients, might limit overtesting, contribute to a more effective use of resources, and help the clinician not underestimate the true risk of KD or MIS-C among patients with an incidental Adenovirus detection.

WHAT IS KNOWN

• Kawasaki Disease (KD), Multisystem Inflammatory Syndrome in Children (MIS-C) and adenoviral infections share overlapping clinical presentation in persistently febrile children, making differential diagnosis challenging. • Scoring systems have been developed to identify high-risk KD patients and discriminate KD from MIS-C patients.

WHAT IS NEW

• This is the first scoring model based on clinical criteria to distinguish adenoviral infection from KD and MIS-C. • The score might be used by general pediatricians before referring febrile children to the emergency department.

Clinical features analysis of Kawasaki disease with abdominal symptoms as the first manifestation

To investigate the clinical characteristics of Kawasaki disease (KD) presenting with abdominal manifestation as the first manifestation. Our findings may help improve the cognition of KD with abdominal complications, and avoid misdiagnosis and missed diagnosis. A retrospective analysis was conducted of 1490 KD patients admitted to Shengjing Hospital between January 2019 and March 2022. Clinical characteristics, related factors, and prognosis of KD with abdominal manifestation as first manifestation were analyzed. Based on the presenting symptoms, patients were divided into gastrointestinal symptom group (n = 141), liver dysfunction group (n = 55), and control group (n = 1294). In the gastrointestinal group, diarrhea [100 cases (70.9%)], vomiting [55 cases (39.0%)], and abdominal pain [34 cases (24.1%)] were the most common symptoms at onset. 8 cases (5.7%) were complicated with pseudo-intestinal obstruction, 6 cases (4.3%) with ischemic colitis, 5 cases (3.5%) with pancreatitis, 2 cases (1.4%) with appendicitis, and 1 case (0.7%) with cholecystitis. Comparied to ordinary gastroenteritis caused by infection, gastroenteritis with KD has longer fever duration before treatment, higher WBC, PLT, CRP, AST levels and lower albumin levels. All patients in the liver dysfunction group had elevated transaminases, and 19 patients (34.5%) presented with jaundice. In the gastrointestinal group, the average hospital stay was 10.3 days, and the incidence of IVIG unresponsiveness and coronary artery lesion were 18.4% and 19.9%, respectively, which were significantly higher than that in the control group. In the liver dysfunction group, the average hospital stay (11.18 days), incidence of IVIG unresponsiveness (25.5%), and incidence of coronary artery lesion (29.1%) were significantly higher than that in the control group. On multivariate logistic regression analysis, gastrointestinal involvement, fever duration, ALT, PLT, and CRP were identified as risk factors for CAL, younger age, gastrointestinal involvement and fever duration were risk factors for IVIG unresponsiveness.  Conclusion: KD with gastrointestinal involvement is associated with a higher risk of IVIG unresponsiveness and coronary artery lesion. KD should be considered in the differential diagnosis of children with acute fever, especially those with gastrointestinal involvement and liver dysfunction. What is Known: • Fever duration, PLT, and CRP were identified as risk factors for CAL. Timely diagnosis and application of IVIG treatment can avoid exploratory laparotomy for ileus, appendectomy for misdiagnosed appendicitis, colonoscopy for misdiagnosed inflammatory bowel disease, and reduce the complications of CAL and IVIG unresponsiveness. What is New: • Abdominal symptoms as the first manifestation can be an independent risk factor for CAL and IVIG unresponsiveness. KD should be considered in the differential diagnosis of children with acute fever, especially those with gastrointestinal symptoms or liver dysfunction. • Gastroenteritis in KD group had longer fever duration before treatment, accompanied with higher WBC, PLT, CRP, AST levels and lower albumin levels than those gastroenteritis caused by infection. Therefore, high attention should be paid to the possibility of KD when gastroenteritis accompanied by along fever duration, high WBC, PLT, CRP, AST level or lowalbumin level.

Pathophysiological and clinical point of view on Kawasaki disease and MIS-C

This article compares two important pathophysiological states, Kawasaki disease, and multisystem inflammatory syndrome, in children associated with COVID-19 (MIS-C). Both occur predominantly in children, have a temporal association with an infectious agent, and are associated with immune-system alteration and systemic inflammation under certain circumstances. The two share common pathophysiology, including enhancement of interleukin-1 neutrophils, activation of the inflammasome, pyroptosis, or NETosis. Moreover, the clinical presentation of the diseases overlaps. However, they are indeed two separate diseases, proven by the differences in the epidemiological and etiological aspects and the pathophysiological processes involved in the development and frequency of some clinical signs. This article highlights potentially exciting areas that have not yet been studied in detail, which could help better understand the development of these diseases.

French national diagnostic and care protocol for Kawasaki disease

Kawasaki disease (KD) is an acute vasculitis with a particular tropism for the coronary arteries. KD mainly affects male children between 6 months and 5 years of age. The diagnosis is clinical, based on the international American Heart Association criteria. It should be systematically considered in children with a fever, either of 5 days or more, or of 3 days if all other criteria are present. It is important to note that most children present with marked irritability and may have digestive signs. Although the biological inflammatory response is not specific, it is of great value for the diagnosis. Because of the difficulty of recognising incomplete or atypical forms of KD, and the need for urgent treatment, the child should be referred to a paediatric hospital as soon as the diagnosis is suspected. In the event of signs of heart failure (pallor, tachycardia, polypnea, sweating, hepatomegaly, unstable blood pressure), medical transfer to an intensive care unit (ICU) is essential. The standard treatment is an infusion of IVIG combined with aspirin (before 10 days of fever, and for a minimum of 6 weeks), which reduces the risk of coronary aneurysms. In case of coronary involvement, antiplatelet therapy can be maintained for life. In case of a giant aneurysm, anticoagulant treatment is added to the antiplatelet agent. The prognosis of KD is generally good and most children recover without sequelae. The prognosis in children with initial coronary involvement depends on the progression of the cardiac anomalies, which are monitored during careful specialised cardiological follow-up.

Kawasaki disease in Malaysia: Biochemical profile, characterization, diagnosis and treatment

Introduction

Kawasaki disease (KD) is an acute idiopathic systemic vasculitis with a self- limiting course that predominantly affects children under 5 years old, particularly in the East Asian countries. Nevertheless, to date, the data on KD in Malaysia are limited. This study aimed to evaluate the epidemiology, clinical features, treatment, and outcomes of KD among the pediatric patients admitted to Hospital Canselor Tunku Muhriz (HCTM), Kuala Lumpur, Malaysia.

Method

A retrospective cohort study of 66,500 pediatric patients presented at HCTM from the year 2004 to 2021 was conducted.

Results

62 KD cases out of 66,500 pediatric admissions were reported, with a male-to-female ratio of 1.58 to 1. Majority of KD patients (95.0%) were younger than 5 years old. Prior infection was reported in 5 KD patients (8.1%). Apart from the classical features, manifestations of various organ systems including cardiovascular (16.1%), gastrointestinal (43.5%), neurological (1.61%), musculoskeletal (1.61%), and genitourinary (17.7%) systems were observed. There was a significant association between sterile pyuria and coronary artery aneurysm (CAA) (p < 0.05). Interestingly, abnormal liver parameters (p < 0.05) and incomplete KD (p < 0.05) were significantly related to IVIG resistance.

Discussion

The presence of family history, immunological disorder, and previous infection in our KD patients suggested that there is a possibility of genetic, immunological, and infectious roles in the pathophysiology of KD. IVIG resistance is more likely to occur in KD patients with hepatic dysfunction or incomplete KD presentation. These findings highlighted the significant contribution of laboratory parameters to the prognosis of KD, prompting more in-depth research on the KD scoring systems and their relevance in this country.

Kawasaki disease complicated with shock syndrome, macrophage activation syndrome, and acute abdomen in children: Two case reports

Background

Kawasaki disease (KD) is an acute systemic vasculitis that can involve multiple organs. Few reports have been published about KD patients presenting with multiple complications such as acute abdomen, KD shock syndrome (KDSS), and macrophage activation syndrome (MAS).

Case Description

We present the cases of two males (9 and 12 years old) diagnosed with KD accompanied by rare manifestations. Case 1 is a 9-year-old male treated for acute appendicitis, KDSS, and MAS. Case 2 is a 12-year-old male who presented with KDSS, MAS, and an ileal perforation. They were treated with intravenous immunoglobulin, aspirin, high-dose corticosteroids, vasoactive drugs, and symptomatic treatment, with good outcomes.

Conclusions

Clinicians should be aware of the possibility of KD in the presence of fever and unusual manifestations, such as severe inflammatory indicators and acute abdomen that is nonresponsive to antibiotic therapy. Meanwhile, KD-related unusual complications should be recognized, such as KDSS and MAS.

Imaging of intestinal vasculitis focusing on MR and CT enterography: a two-way street between radiologic findings and clinical data

Diagnosis of intestinal vasculitis is often challenging due to the non-specific clinical and imaging findings. Vasculitides with gastrointestinal (GI) manifestations are rare, but their diagnosis holds immense significance as late or missed recognition can result in high mortality rates. Given the resemblance of radiologic findings with some other entities, GI vasculitis is often overlooked on small bowel studies done using computed tomography/magnetic resonance enterography (CTE/MRE). Hereon, we reviewed radiologic findings of vasculitis with gastrointestinal involvement on CTE and MRE. The variety of findings on MRE/CTE depend upon the size of the involved vessels. Signs of intestinal ischemia, e.g., mural thickening, submucosal edema, mural hyperenhancement, and restricted diffusion on diffusion-weighted imaging, are common in intestinal vasculitis. Involvement of the abdominal aorta and the major visceral arteries is presented as concentric mural thickening, transmural calcification, luminal stenosis, occlusion, aneurysmal changes, and collateral vessels. Such findings can be observed particularly in large- and medium-vessel vasculitis. The presence of extra-intestinal findings, including within the liver, kidneys, or spleen in the form of focal areas of infarction or heterogeneous enhancement due to microvascular involvement, can be another radiologic clue in diagnosis of vasculitis. The link between the clinical/laboratory findings and MRE/CTE abnormalities needs to be corresponded when it comes to the diagnosis of intestinal vasculitis.

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.

Clinical Manifestations and Laboratory Findings of Kawasaki Disease: Beyond the Classic Diagnostic Features

Kawasaki disease (KD) has shown a marked increase in trend over the globe, especially within the last two decades. Kawasaki disease is often seen in the paediatric population below five years old, while it is rare for those who are beyond that age. Up to this date, no exact causes has been identified although KD was found more than half a century ago. The underlying pathogenesis of the disease is still unelucidated, and researchers are trying to unlock the mystery of KD. To further complicate the diagnosis and the prompt management, a specific biomarker for the diagnosis of KD is yet to be discovered, making it hard to differentiate between KD and other diseases with a similar presentation. Nonetheless, since its discovery, clinicians and scientists alike had known more about the different clinical aspects of typical KD. Thus, this article intends to revisit and review the various clinical manifestations and laboratory characteristics of KD in order to guide the diagnosis of KD.

Combination of fecal calprotectin and initial coronary dimensions to predict coronary artery lesions persistence in Kawasaki disease

Kawasaki Disease (KD) is systemic vasculitis involving medium-sized vessels in children. The aim of our study is to determine if fecal calprotectin (FC) could be useful in predicting the development or persistence of coronary artery lesions (CALs) in KD. We conducted a prospective monocentric study including all consecutive diagnoses of. Clinical, laboratory, echocardiographic data were recorded during the acute and subacute phase, including FC. Correlations among laboratory values, FC, clinical manifestations, IVIG-responsiveness and CALs development were investigated. We enrolled 26 children (76.9% boys; median age 34.5 months). The combination of FC > 250 microg/g and z-score > 2 during the acute phase was associated with the persistence of CALs (p = 0.022). A z-score > 2 alone during the acute phase was not related to CALs during the subacute stage (p > 0.05). A neutrophil percentage > 70% and WBC > 15,000/mmc during the acute phase significantly correlated with the presence of CALs during the subacute phase (p = 0.008). C-reactive protein (CRP) > 13 mg/dL at KD onset was significantly associated with the presence of CALs during the acute (p = 0.017) and subacute phase (p = 0.001). The combination of FC > 250 microg/g and a z-score > 2 during the acute phase of KD may be used as a predictor of CALs persistence. It can be useful especially in children with an initial CRP < 13 mg/dl.

Comparison of Laboratory Data between Children with Kawasaki Disease and COVID-19

Background: Coronavirus disease 2019 (COVID-19) has been an emerging, rapidly evolving situation in China since late 2019 and has even become a worldwide pandemic. The first case of severe childhood novel coronavirus pneumonia in China was reported in March 2020 in Wuhan. The severity differs between adults and children, with lower death rates and decreased severity for individuals under the age of 20 years. Increased cases of Kawasaki disease (KD) have been reported from New York City and some areas of Italy and the U.K., with almost a 6–10 times increase when compared to previous years. We conducted this study to compare characteristics and laboratory data between KD and COVID-19 in children. Methods: We obtained a total of 24 children with COVID-19 from a literature review and 268 KD cases from our hospital via retrospective chart review. Results: We found that patients with KD have higher levels of white blood cells (WBCs), platelets, neutrophil percentage, C-reactive protein (CRP), procalcitonin, and aspartate aminotransferase (AST) and a higher body temperature, while patients with COVID-19 have a higher age, hemoglobin levels, and lymphocyte percentage. After performing multiple logistic regression analysis, we found that age, WBCs, platelets, procalcitonin, and AST are identical markers for distinguishing COVID-19 from KD in children. Conclusion: In this COVID-19 pandemic period, clinicians should pay attention to children with COVID-19 infection when high WBC, platelet, procalcitonin, and AST values are present in order to provide early diagnosis for KD or multisystem inflammatory syndrome in children (MIS-C).

Cardiovascular Manifestations in Multisystem Inflammatory Syndrome in Children (MIS-C) Associated with COVID-19 According to Age

Cardiac involvement in multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus-19 disease is often observed with a high risk of heart failure. The aim is to describe cardiovascular involvement, management and early outcome in MIS-C by comparing cardiovascular manifestations in children younger and older than 6 years old. This retrospective observational study included 25 children with MIS-C, admitted to a single pediatric center between March 2020 and September 2021. The median age was 5 years (13 patients under 6 years and 12 over 6 years); coronary artery abnormalities were observed in 77% of preschoolers, with small and medium aneurysms in half of the cases and two cases of mild ventricular dysfunction. School-age children presented myopericardial involvement with mild to moderate ventricular dysfunction in 67% of cases, and two cases of transient coronary dilatation. There was a significant NT-pro-BNP and inflammatory markers increase in 25 of the patients, and mild elevation of troponin I in 9. All patients were treated with intravenous immunoglobulin and corticosteroids, and 8 with anakinra. None of the patients needed inotropes or intensive care unit admission. Our study shows the frequent cardiovascular involvement in MIS-C with a peculiar distribution, according to different age group: coronary artery anomalies were more frequent in the younger group, and myopericardial disease in the older one. A prompt multitarget, anti-inflammatory therapy could probably contribute to a favorable outcome.

Case report: Histological findings of peri-appendicitis in three children with SARS-CoV-2 - related multisystem inflammatory syndrome: A mark for systemic inflammation?

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a rare but serious condition that can potentially develop after SARS-CoV-2 infection in children. Gastrointestinal manifestation in MIS-C can mimic acute abdomen, potentially leading to unnecessary surgical treatment. Immune-mediated mechanisms seem to be a determining factor in its pathogenesis, and histological studies can help to shed light on this aspect. We describe three cases of children diagnosed with MIS-C that underwent appendectomy.

METHODS

We retrospectively collected the clinical features and histological findings of three previously healthy children who underwent appendectomy for clinical suspicion of acute appendicitis but were later diagnosed with MIS-C.

FINDINGS

The three children presented with prominent abdominal manifestations and fever leading to the suspicion of acute abdomen. Histological findings showed transmural and perivascular inflammation. Notably, CD68⁺ macrophages were predominant in the child with milder abdominal symptoms without cardiac injury, while CD3⁺ lymphocytes in the patient presented with more severe abdominal pain and cardiovascular involvement at admission.

INTERPRETATION

Gastrointestinal symptoms of children with MIS-C improve after proper immunomodulatory therapy, conversely showing inadequate response to surgical appendectomy. Histological findings revealed different inflammatory cell infiltration that primarily involved perivisceral fat and vessels, and subsequently mucosal tissue, in contrast to other forms of acute appendicitis. Our findings suggest that this kind of peri-appendicitis in MIS-C could represent a focal sign of systemic inflammation, with different histological patterns compared to other forms of acute appendicitis.

Acute Abdomen—A Clinical Presentation of MIS-C in Children

Objective Multisystemic inflammatory syndrome in children (MIS-C) is characterized by persistent fever, systemic hyperinflammation, and multiple-organ dysfunction. There are a few reports about MIS-C presenting with acute abdomen. The aim of this study was to demonstrate the clinical characteristics and treatment options for MIS-C-related acute abdomen and appendicitis.

Methods This was a retrospective study conducted between April 2020 and October 2020 in our pediatric intensive care unit in Turkey. Patients between the ages of 1 month and 18 years who presented with acute abdomen and were ultimately diagnosed with MIS-C were included.

Results Seven patients with a median age of 12.5 (interquartile range 10.5–13) years were enrolled. Four were females. The most frequent symptoms were fever, abdominal pain, and vomiting. Three patients had involvement of the appendix that required surgical intervention. All pathology reports were compatible with appendicitis. The other patients also had an acute abdomen. One patient had malignant hyperthermia during induction of anesthesia, so surgery was postponed and medical management was commenced. The clinical picture regressed with immunomodulation. All patients were treated with intravenous immunoglobulin and steroids. Four patients with acute abdomens improved with immunomodulation, and surgery was not needed.

Conclusion MIS-C may present with an acute abdomen. Immunomodulation should be considered instead of surgery if the clinical course is not complicated.

Learning about Kawasaki disease from COVID-19 and the Multisystem Inflammatory Syndrome in Children

PURPOSE OF REVIEW

Multisystem Inflammatory Syndrome in Children (MIS-C) is a novel syndrome that has appeared in the wake of the severe acute respiratory syndrome coronavirus -2 pandemic, with features that overlap with Kawasaki disease (KD). As a result, new interest and focus have arisen in KD, and specifically mechanisms of the disease.

RECENT FINDINGS

A major question in the literature on the nature of MIS-C is if, and how, it may be related to KD. This has been explored using component analysis type studies, as well as other unsupervised analysis, as well as direct comparisons. At present, the answer to this question remains opaque, and several studies have interpreted their findings in opposing ways. Studies seem to suggest some relationship, but that MIS-C and KD are not the same syndrome.

SUMMARY

Study of MIS-C strengthens the likelihood that KD is a postinfectious immune response, and that perhaps multiple infectious agents or viruses underlie the disease. MIS-C and KD, while not the same disease, could plausibly be sibling disorders that fall under a larger syndrome of postacute autoimmune febrile responses to infection, along with Kawasaki shock syndrome.

Atypical Kawasaki Disease in an Adolescent with Multivisceral Involvement

Kawasaki disease (KD) is a vasculitis mostly seen in children aged less than 5 years. It can involve different organs and tissues. Its diagnosis is based on the clinical criteria of the American Heart Association (AHA). We report a case of a Moroccan adolescent with an atypical presentation of KD initially treated as typhoid fever. Gastrointestinal, renal, and pulmonary signs were the main clinical findings that made the diagnosis of KD challenging and delayed. The consequence was a severe cardiac damage with myocarditis and coronary artery dilation. KD is uncommon in adolescents, and it is important to recognize the atypical forms and the different presentations of KD in order to prevent the delay of diagnosis and treatment, and hence the cardiac complications.

An update on the microbiome in vasculitis

PURPOSE OF REVIEW

To summarize recent evidence regarding the presence and potential role of the microbiome in systemic vasculitides.

RECENT FINDINGS

Microbiomic descriptions are now available in patients with small, medium and large vessel vasculitis. The majority of studies have evaluated gastrointestinal inhabitants, with a smaller number of studies describing the nasal, pulmonary or vascular microbiomes. Most published studies are observational and cross-sectional. Dysbiosis is seen frequently in vasculitis patients with reduced microbial diversity observed in nasal, fecal and vascular samples compared with disease and/or healthy controls. Predominant bacteria vary, but overall, patients with vasculitis tend to have more pathogenic and less commensal bacteria in active disease. In the few longitudinal studies available, improvement or resolution of dysbiosis has been observed following vasculitis treatment and improved disease activity.

SUMMARY

Dysbiosis and reduced microbial diversity has been identified in patients with small, medium and large vessel vasculitis. Although limited data suggests microbiomes may 'normalize' following immunosuppression, cause or effect cannot be determined. It is hypothesized that microbial disruption in a genetically susceptible individual may trigger excessive host immune activation and vasculitis; however, larger studies with longitudinal and translational design are needed to further our current understanding.

Multisystem inflammatory syndrome in children is driven by zonulin-dependent loss of gut mucosal barrier

BACKGROUNDWeeks after SARS-CoV-2 infection or exposure, some children develop a severe, life-threatening illness called multisystem inflammatory syndrome in children (MIS-C). Gastrointestinal (GI) symptoms are common in patients with MIS-C, and a severe hyperinflammatory response ensues with potential for cardiac complications. The cause of MIS-C has not been identified to date.METHODSHere, we analyzed biospecimens from 100 children: 19 with MIS-C, 26 with acute COVID-19, and 55 controls. Stools were assessed for SARS-CoV-2 by reverse transcription PCR (RT-PCR), and plasma was examined for markers of breakdown of mucosal barrier integrity, including zonulin. Ultrasensitive antigen detection was used to probe for SARS-CoV-2 antigenemia in plasma, and immune responses were characterized. As a proof of concept, we treated a patient with MIS-C with larazotide, a zonulin antagonist, and monitored the effect on antigenemia and the patient's clinical response.RESULTSWe showed that in children with MIS-C, a prolonged presence of SARS-CoV-2 in the GI tract led to the release of zonulin, a biomarker of intestinal permeability, with subsequent trafficking of SARS-CoV-2 antigens into the bloodstream, leading to hyperinflammation. The patient with MIS-C treated with larazotide had a coinciding decrease in plasma SARS-CoV-2 spike antigen levels and inflammatory markers and a resultant clinical improvement above that achieved with currently available treatments.CONCLUSIONThese mechanistic data on MIS-C pathogenesis provide insight into targets for diagnosing, treating, and preventing MIS-C, which are urgently needed for this increasingly common severe COVID-19-related disease in children.

Kawasaki disease presenting after intussusception: a case report

INTRODUCTION

Kawasaki disease is a common vasculitis of unknown etiology that occurs mainly in preschool children. It manifests as a self-limited acute febrile illness with other features including extremity changes, cervical lymphadenopathy, oropharyngeal changes, truncal rash, and conjunctivitis. Intestinal involvement is not uncommon, with abdominal pain and vomiting being the most frequently reported symptoms. Intussusception has been described as a manifestation or complication of this disease, but few reports exist in literature.

CASE PRESENTATION

A 7-month-old boy of Asian origin who presented with vomiting and passage of bloody mucoid stool was diagnosed with intussusception that was successfully reduced during emergency laparotomy. The baby was discharged home post-surgery following clinical improvement. He was readmitted on the fourth postoperative day with fever, irritability, and diarrhea. He was investigated and treated for presumed intraabdominal sepsis with multiple antibiotics with no improvement. He gradually developed the mucocutaneous features of Kawasaki disease and was treated with intravenous immunoglobulin and aspirin with good outcome.

CONCLUSION

Intussusception and Kawasaki disease both commonly occur in children less than 2 years old. It is important to include Kawasaki disease as a differential diagnosis in children of this age who present with an acute febrile illness and gastrointestinal symptoms. A common underlying pathologic process could be contributing to both conditions.

Kawasaki Disease Complicated by Late-Onset Fatal Cerebral Infarction: A Case Report and Literature Review

Background: Cerebral infarction is a rare neurological complication of Kawasaki disease (KD) and occurs in the acute or subacute stage. There have been no reported cases of late-onset fatal cerebral infarction presenting over 1 year after the onset of KD. Case Presentation: A 5-month-old male patient with KD received timely intravenous immunoglobulin therapy; however, extensive coronary artery aneurysms (CAA) and coronary artery thrombosis (CAT) developed 1 month later. Anticoagulation and thrombolytic agents were suggested, but the child's parents refused. Fifteen months after KD onset, an attack of syncope left him with left hemiplegia; brain computerized tomography (CT) scans revealed cerebral infarction of the right basal ganglion without hemorrhage. Magnetic resonance angiography (MRA) revealed severe stenosis of the right middle cerebral artery, and a series of tests were performed to exclude other causes of cerebral infarction. Considering the cerebral infarction and CAT, combination therapy with urokinase and low-molecular-weight heparin (LMWH) was initiated within 24 h of syncope onset, together with oral aspirin and clopidogrel. Five days later, his clinical symptoms partially regressed and he was discharged. Unfortunately, 5 days after discharge, his clinical condition suddenly deteriorated. Repeat brain CT showed hemorrhagic stroke involving the entire left cerebral area, in addition to the previous cerebral infarction in the right basal ganglion, with obvious secondary cerebral swelling and edema, which might have been caused by previous thrombolysis. Severe cerebral hernias developed quickly. Regrettably, the patient's parents abandoned treatment because of economic factors and unfavorable prognosis, and he died soon after. Conclusions: Cerebral infarction and cerebral artery stenosis can develop late, even 1 year after the onset of KD. Pediatricians should be aware of the possibility of cerebrovascular involvement in addition to cardiac complications during long-term follow-up of KD patients. Prompt anticoagulation therapy and regular neuroimaging evaluation are essential for the management of patients with KD with giant CAA and/or CAT.

Kawasaki Disease Complicated by Salmonella oranienburg Coinfection

Kawasaki disease is a medium vessel vasculitis with a multisystem presentation affecting 9-20 per 100,000 children under 5 years of age in the United States. Salmonella coinfection has not been previously described. We present a 12-month-old vaccinated male with Kawasaki disease in the setting of Salmonella bacteremia. Initial intervention for the Kawasaki disease with IVIG was ineffective, prompting adjunctive therapy with anakinra, with eventual full recovery. Concurrent Kawasaki disease and bacteremia may confound diagnosis and necessitate nontraditional treatment approaches.

Tight junction protein ZO-1 in Kawasaki disease

Background

Kawasaki disease (KD) is a form of systemic febrile vasculitis that is complicated with coronary artery lesions (CAL). The tight junctions that maintain the intestinal barrier also play a role in systemic inflammatory diseases. Serum zonula occludens-1 (ZO-1) expression was found to be significantly lower in asthmatic patients, and another study reported that elevated systemic ZO-1 was positively correlated with inflammation in cirrhotic patients. A murine model of KD vasculitis demonstrated that vasculitis depended on intestinal barrier dysfunction, which is maintained by tight junctions. In this study, we aimed to investigate the role of the tight junction zonula occludens-1 (ZO-1) in the treatment response of intravenous immunoglobulin (IVIG) and the occurrence of CAL formation in KD patients.

Methods

We enrolled 40 KD patients, 12 healthy controls, and 12 febrile controls in this study. The serum levels of tight junction ZO-1 were determined by enzyme-linked immunosorbent assay.

Results

The serum ZO-1 level was higher in the fever control group but did not reach a statistical significance. KD patients who received a second dose of IVIG treatment due to initial IVIG unresponsiveness had a higher serum levels of tight junction ZO-1, but without statistical significance (2.15 ± 0.18 vs. 2.69 ± 0.31 ng/mL, p = 0.058). KD patients who developed a CAL demonstrated a significant lower serum tight junction ZO-1 levels than KD without CAL formation (1.89 ± 0.16 vs. 2.39 ± 0.15 ng/mL, p = 0.027). After multiple logistic regression analysis, ZO-1 levels [(95% confidence interval (CI): 0.058 ~ 0.941, odds ratio (OR) = 0.235, p = 0.041)] showed as the risk factor for CAL formation.

Conclusion

Serum levels of tight junction ZO-1 levels were lower in KD patients than fever controls and associated with CAL formation.

Surveillance of COVID-19-Associated Multisystem Inflammatory Syndrome in Children, South Korea

A concerning development during the coronavirus disease pandemic has been multisystem inflammatory syndrome in children. Reports of this condition in East Asia have been limited. In South Korea, 3 cases were reported to the national surveillance system for multisystem inflammatory syndrome in children. All case-patients were hospitalized and survived with no major disease sequelae.

Age-related differences in clinical characteristics of Kawasaki disease

This study aimed to examine and summarize clinical characteristics of Kawasaki disease (KD) at different ages to further strengthen clinicians understanding of children with KD, improving the level of diagnosis, and reducing coronary artery complications of KD. A total of 398 patients with KD who were diagnosed between January 2016 and December 2017 were reviewed retrospectively. These participants were allocated into three groups according to age: group A (<1 year, n=62), group B (≥1 and <5 years, n=286), and group C (≥5 years, n=50). Clinical manifestations, laboratory results, and echocardiographic findings were compared among the groups. Most (71.86%) patients with KD were aged 1-5 years. The prevalence of cervical lymphadenopathy was lowest in group A. The duration of fever before admission was longest in group A. The rate of cervical lymphadenopathy and laboratory data were different among the groups. Group A had higher frequencies of gastrointestinal involvement, neurological symptoms, and redness at the Bacillus Calmette-Guerin inoculation site than the other groups. Infants aged <1 year with KD often have a longer duration of fever before admission, a lower prevalence of cervical lymphadenopathy, and a higher prevalence of gastrointestinal and neurological symptoms.

Gastrointestinal involvement in childhood vasculitides

AIM

The aim of this narrative review was to provide a comprehensive summary of the characteristics of gastrointestinal (GI) involvement in the most common paediatric primary vasculitides.

METHODS

We used PubMed to primarily identify papers, reviews, case series and editorials published in English from 2000 until 31 January 2020. Based on this, we report the prevalence, clinical manifestations, diagnostic approaches and management of GI involvement in each vasculitis.

RESULTS

Vasculitides are inflammatory blood vessel diseases, and the majority can affect the GI system with vascular, GI tract or solid organ involvement. GI involvement can sometimes complicate and delay the correct diagnosis. Clinical findings are usually nonspecific symptoms, such as fever, abdominal pain, nausea, vomiting and diarrhoea. Bleeding should alert paediatricians to the possibility of severe complicated vasculitis. Diagnosis relies mostly on imaging. If it goes unrecognised, GI involvement in paediatric vasculitis is a serious cause of morbidity and even mortality, related to bowel ischaemia and perforation. Treatment of GI symptoms depends on the type of vasculitis and usually involves high-dose steroids and immunosuppressants.

CONCLUSION

GI manifestations in the most common paediatric primary vasculitides were usually nonspecific, diagnosis mostly relied on imaging, and treatment usually involved high-dose corticosteroids and immunosuppressants.

Acute cholestasis as uncommon onset of Kawasaki disease: a case report

BACKGROUND

Kawasaki disease (KD) or mucocutaneous lymph node syndrome is a vasculitis that mostly occurs in young children. Adult-onset KD (AKD) is rare and often misdiagnosed. Here we report a rare case of KD with cholestasis as principal symptom.

CASE PRESENTATION

A 43-year-old caucasian man was admitted to our hospital for high fever, lack of appetite related to nausea and vomiting, headache and significant malaise. Physical examination highlighted fever, increasing jaundice, bilateral laterocervical lymph nodes, erythema of the palms, and strikingly red lips and conjunctiva. The clinical course was complicated by arterial hypotension, tachycardia, decreasing haemoglobin, increasing acute phase reactants tests, and multiorgan failure. Due to cardiovascular instability the patient was admitted to the local Intensive Care Unit. Chest X-ray, abdominal ultrasound, chest and abdominal CT and Colangio Magnetic Resonance were normal. Jaundice was investigated and infections, autoimmune diseases or drugs adverse reactions, were excluded. Also coronary artery computed tomography was carried out excluding coronary artery aneurysms. Broad-spectrum antibiotics were not effective. After exclusion other possible conditions, diagnosis of KD was set. He was treated with high doses of corticosteroids and acetylsalicylic acid and clinical conditions as well as laboratory exams improved.

CONCLUSIONS

This report dealing with an adult onset of atypical KD may be of benefit to physicians of various specialties, including primary care doctors, hospital internists, intensivists and gastroenterologists due to its peculiarities. It demonstrates that a case of prolonged fever unresponsive to antibiotics and related to cholestatic jaundice, oedema or erythema of the extremity associated with desquamation of feet and hands, and red eyes, may suggest atypical form of KD.

Considerations for nutrition support in critically ill children with COVID-19 and paediatric inflammatory multisystem syndrome temporally associated with COVID-19

There are reports of children COVID-19 or COVID-19 like symptoms with hyperinflammatory multisystem syndrome, ARDS, gastrointestinal and atypical Kawasaki disease presenting to PICU worldwide temporally associated with COVID-19, for which there are important nutrition support considerations. As a result, the European Society of Pediatric and Neonatal Intensive Care – Metabolism, Endocrine and Nutrition group (ESPNIC-MEN) and paediatric nutritionists working in PICUs are being consulted regarding nutrition management of critically ill children with COVID-19 or COVID-19 like symptoms. Therefore, the aim of this short report is to provide a summary of nutrition support recommendations for critically ill children with COVID-19. They are based on the ESPNIC-MEN section recommendations published in January 2020 and surviving sepsis recommendations from February 2020.

A Case of Multisystem Inflammatory Syndrome in Children Mimicking Acute Appendicitis in a COVID-19 Pandemic Area

The outbreak of the novel coronavirus (2019-nCoV) began in Wuhan, China and spread rapidly throughout the world. As of now, there have been numerous reports demonstrating clinical, radiological and pathological findings in adults. In children, the disease has essentially been seen as mild and self-limiting. However, more recently, children have been presenting with findings reminiscent of Kawasaki's disease. And secondary to this, the benign nature of COVID-19 disease in children is beginning to be challenged. This phenomenon is now referred to as multisystem inflammatory syndrome in children (MIS-C). Further understanding the clinical course in MIS-C and its temporal association with coronavirus disease 2019 will be paramount for treatment and public health decision making. This correspondence describes a case of MIS-C with gastrointestinal manifestations mimicking acute appendicitis in a child presenting from a COVID-19 endemic area.

Non-coronary cardiac events, younger age, and IVIG unresponsiveness increase the risk for coronary aneurysms in Italian children with Kawasaki disease

OBJECTIVES

Kawasaki disease (KD) is the most frequent cause of acquired heart disease in children in high-income countries because of coronary artery involvement. Risk factors for coronary lesions can vary in consideration of different genetic background and environmental factors.

METHODS

Multicenter retrospective and prospective study including 372 consecutive children (58% boys; mean age 34.3 ± 30.3 months, Caucasian 85%) was diagnosed with KD. We divided the cohort into 2 groups according to the presence of coronary anomalies (CAA) and aneurysms. We compared the groups and studied the risk factors for CAA and for aneurysms, the most severe lesions.

RESULTS

Children with CAA were 91/372 (24.46%, aneurysms 20/372, 5.37%). Children with CAA were more likely to have a longer duration of fever (p < 0.001), later day of treatment (p < 0.001), to be IVIG non-responders and late treated (p < 0.001), while age, clinical presentation, and seasonality were not different. They also had significantly higher WBC and neutrophils, lower lymphocytes, Hb and Na during the acute stage, and slower resolution of inflammation. Age, IVIG unresponsiveness, and presence of non-coronary cardiac findings were independent risk factors for CAA and for aneurysms, while neutrophils just for CAA. Age under 6 months was a risk factor for the aneurysm. Aneurysms occurred more frequently in the first quartile of the age of KD onset (under 14 months).

CONCLUSION

Very young children with non-coronary cardiac findings are at increased risk for a more severe form of KD with aneurysms. These children could benefit from adjunctive therapy beside IVIG, especially if they have higher markers of inflammation, particularly neutrophils. Key points • Risk factors for coronary lesions can vary in consideration of different genetic background and environmental factors. • Risk factors for coronary involvement have been extensively studied in the Asian population, and others have been validated in cohorts with mixed ethnicities. • In our predominantly Caucasian population, non-coronary cardiac findings, age younger than 6 months, and IVIG unresponsiveness are independent risk factors for a more severe form of KD with aneurysms.

Grisel's syndrome in Kawasaki disease

BACKGROUND

Approximately 50-70% of patients with Kawasaki disease (KD) could present with cervical lymphadenopathy associated with deep neck inflammation, which may result in Grisel's syndrome (GS). Given the possibility of neurological impairment owing to GS, it is important to understand the disease profile in KD. Therefore, we carried out this study to investigate this possible complication of KD, with the aim of improving pediatricians' recognition and awareness.

METHODS

Patients with KD complicated by GS in our hospital were retrospectively recruited for our study. The profiles of patients with GS (n = 10) were compared to those patients without GS (n = 1254). All the available literature describing these complications of KD was reviewed.

RESULTS

The incidence of GS in KD was 0.6% in our population. Compared to patients without GS, KD patients with GS were older, presented with a significantly lower male:female ratio, and a higher incidence of cervical lymphadenopathy, a higher level of neutrophil count, and erythrocyte sedimentation rate. Ten articles reporting 14 KD patients with GS were reviewed. Of the total 24 patients, GS affected 7 males and 17 females, aged from 3.5 to 9 years old. Encouragingly, no delayed diagnosis and treatment of KD was found, and all patients received conservative therapy for GS, without intravenous immunoglobulin resistance, coronary artery lesions, and neurological impairment.

CONCLUSIONS

GS is a rare complication of KD with an incidence of 0.6%, predominantly affecting older, female children. The overall outcome of this disorder in KD was satisfactory with conservative therapy. Pediatricians, especially pediatric surgeons, should recognize and be aware of this possible complication of KD to avoid misdiagnosis and overtreatment.

Neurological involvement in Kawasaki disease: a retrospective study

BACKGROUND

Kawasaki disease (KD) is an acute, self-limiting systemic vasculitis that predominately affects children. Neurological involvement is a known complication of KD, however, its association with KD severity remains elusive. We aimed to systematically describe the general manifestations of neurological involvement in KD, determine whether neurological involvement is a marker of disease severity in patients with KD, and assess the relationship of such involvement with intravenous immunoglobulin (IVIG) resistance and coronary artery lesions (CALs).

METHODS

We retrospectively reviewed data from 1582 patients with KD between January 2013 and December 2017. Profiles of patients with neurological symptoms (group A, n = 80) were compared to those of gender- and admission date-matched patients without neurological involvement (group B, n = 512). Multivariate logistic regression analyses were performed to determine whether neurological involvement was significantly associated with IVIG resistance.

RESULTS

Neurological involvement was observed in 5.1% (80/1582) of patients with KD. The neurological manifestations were diffuse, presenting as headache (13/80, 16.3%), convulsions (14/80, 17.5%), somnolence (40/80, 50.1%), extreme irritability (21/80, 26.3%), signs of meningeal irritation (15/80, 18.8%), bulging fontanelles (7/80, 8.8%), and facial palsy (1/80, 1.3%). Neurological symptoms represented the initial and/or predominant manifestation in 47.5% (38/80) of patients with KD. The incidence of IVIG resistance and levels of inflammatory markers were higher in group A than in group B. However, neurological involvement was not an independent risk factor for IVIG resistance or CALs.

CONCLUSION

Rates of neurological involvement were relatively low in patients with KD. Neurological involvement was associated with an increased risk of IVIG resistance and severe inflammatory burden. Our results highlight the need for pediatricians to recognize KD with neurological involvement and the importance of standard IVIG therapy.

TRIAL REGISTRATION

Retrospectively registered.

Kawasaki disease: pathophysiology and insights from mouse models

Kawasaki disease is an acute febrile illness and systemic vasculitis of unknown aetiology that predominantly afflicts young children, causes coronary artery aneurysms and can result in long-term cardiovascular sequelae. Kawasaki disease is the leading cause of acquired heart disease among children in the USA. Coronary artery aneurysms develop in some untreated children with Kawasaki disease, leading to ischaemic heart disease and myocardial infarction. Although intravenous immunoglobulin (IVIG) treatment reduces the risk of development of coronary artery aneurysms, some children have IVIG-resistant Kawasaki disease and are at increased risk of developing coronary artery damage. In addition, the lack of specific diagnostic tests and biomarkers for Kawasaki disease make early diagnosis and treatment challenging. The use of experimental mouse models of Kawasaki disease vasculitis has considerably improved our understanding of the pathology of the disease and helped characterize the cellular and molecular immune mechanisms contributing to cardiovascular complications, in turn leading to the development of innovative therapeutic approaches. Here, we outline the pathophysiology of Kawasaki disease and summarize and discuss the progress gained from experimental mouse models and their potential therapeutic translation to human disease.

This Review outlines the pathophysiology of Kawasaki disease and discusses the progress gained from experimental mouse models and their potential therapeutic translation to human disease.

Kawasaki disease is a childhood systemic vasculitis leading to the development of coronary artery aneurysms; it is the leading cause of acquired heart disease in children in developed countries.

The cause of Kawasaki disease is unknown, although it is suspected to be triggered by an unidentified infectious pathogen in genetically predisposed children.

Kawasaki disease might not be a normal immune response to an unusual environmental stimulus, but rather a genetically determined unusual and uncontrolled immune response to a common stimulus.

Although the aetiological agent in humans is unknown, mouse models of Kawasaki disease vasculitis demonstrate similar pathological features and have substantially accelerated discoveries in the field.

Genetic and transcriptomic analysis of blood samples from patients with Kawasaki disease and experimental evidence generated using mouse models have demonstrated the critical role of IL-1β in the pathogenesis of this disease and the therapeutic potential of targeting this pathway (currently under investigation in clinical trials).

Gastrointestinal hemorrhage before anticoagulant therapy in Kawasaki disease: a case report

Background

Kawasaki disease (KD) is an acute febrile multisystem vasculitis and has been recognized to be the most common cause of acquired heart disease in children. Owing to its propensity to involve vessels throughout the entire body, KD often mimics other disease processes. The diagnosis might be delayed if other prominent symptoms appear before the characteristic clinical features of KD. Although gastrointestinal symptoms including vomiting, diarrhea, and abdominal pain are not uncommon in KD patients, KD with gastrointestinal bleeding is quite rare.

Case presentation

A previously healthy 4-year-old boy initially presented with abdominal pain, followed by fever, rash, and gastrointestinal hemorrhage, eventually diagnosed as complete KD. The patient recovered smoothly after appropriate management and no subsequent complications occurred in the following months.

Conclusion

The diagnosis of KD should be considered in children presenting with abdominal symptoms and fever without definable cause. Pediatricians should be aware of the risk of gastrointestinal bleeding in patients with KD, especially in those with prominent abdominal symptoms.