Kawasaki Disease: A Clinician's Update

The role of nailfold capillaroscopy in pediatric patients with Kawasaki disease

BACKGROUND

Nailfold capillaroscopy has been used as a non-invasive diagnostic method for microvasculature evaluation in various rheumatological disorders. The present study aimed to determine the utility of nailfold capillaroscopy in the diagnosis of Kawasaki Disease (KD).

METHOD

In this case-control study nailfold capillaroscopy was performed in 31 patients with KD and 30 healthy controls. All nailfold images were evaluated for capillary distribution and capillary morphology such as enlargement, tortuosity, and dilatation of the capillaries.

RESULT

Abnormal capillaroscopic diameter was identified in 21 patients from the KD group and 4 patients in the control group. The most common abnormality in capillary diameter was irregular dilatation in 11 (35.4%) KD patients and in 4 people (13.3%) in the control group. Distortions of the normal capillary architecture was commonly seen in the KD group (n=8). A positive correlation was observed between coronary involvement and abnormal capillaroscopic results (r=.65, P<.03). The sensitivity and specificity of capillaroscopy for the diagnosis of KD were 84.0% (95%CI: 63.9-95.5%) and 72.2% (95%CI: 54.8-85.8%), respectively. The PPV and NPV of capillaroscopy for KD were 67.7% (95%CI: 48.6-83.3) and 86.7% (95% CI: 69.3-96.2), respectively.

CONCLUSION

Capillary alterations are more common in KD patients compared to control group. Thus, nailfold capillaroscopy can be useful in detecting these alterations. Capillaroscopy is a sensitive test for detecting capillary alternations in KD patients. It could be used as a feasible diagnostic modality for evaluating microvascular damage in KD.

Comparison of IVIG resistance predictive models in Kawasaki disease

BACKGROUND

We aimed to compare the ten different scores (by Kobayashi, Egami, Harada, Formosa, Sano, Piram et al., Wu et al., Yang et al., Tan et al., and Kanai et al.) to assess their performance in predicting IVIG resistance in Turkish children.

METHODS

Complete and incomplete KD patients diagnosed with KD at Hacettepe University between June 2007 and September 2019 were evaluated retrospectively.

RESULTS

A total of 129 patients, 79 boys (61.2%), with a median age 36 (IQR 19.5-57.0) months were evaluated. Sixteen patients (12.4%) had IVIG resistance. Sensitivity was low for all the ten scores. Tan, Sano, and Egami predictive models had the highest specificity (97.3, 89.4, 86.7%, respectively). Almost all scoring systems distinguished the group of patients with low risk for IVIG resistance but could not differentiate IVIG-resistant patients. Multivariate analysis for the laboratory features showed that platelet count <300 × 10⁹/L and GGT serum levels were independent risk factors for IVIG resistance (OR: 3.896; 95% CI: 1.054-14.404; p = 0.042 and OR: 1.008; 95% CI: 1.001-1.015; p = 0.050).

CONCLUSIONS

The current scoring systems had a low sensitivity for predicting the risk for IVIG resistance in Turkish children. On the other hand, increased serum GGT levels and low platelet count were risk factors for predicting IVIG resistance.

IMPACT

Intravenous immunoglobulin (IVIG) resistance may be observed in 10-20% of patients diagnosed with Kawasaki disease. Coronary artery involvement is more frequent in IVIG-resistant patients. It is important to predict the patients who might develop IVIG resistance to improve prognosis. The performance of the IVIG resistance predictive models in Kawasaki disease in our population is limited due to the low sensitivity.

Síndrome inflamatorio multisistémico en niños con COVID-19: una visión desde la reumatología

La enfermedad por coronavirus 2019 (COVID-19), producida por el SARS-CoV-2, ha tomado una gran importancia en los últimos meses y se encuentra bajo constante investigación por distintas áreas de la medicina, incluida la reumatología, en la búsqueda de la mejor evidencia científica. En el caso de la población pediátrica cobra especial importancia puesto que en un principio se pensaba que el impacto de la pandemia en esta población sería menor, debido a la baja presencia de casos severos, pero la evidencia actual reporta la existencia de cuadros clínicos en niños con diagnóstico de COVID-19 que se caracterizan por un estado inflamatorio alterado consistente en una tormenta de citocinas proinflamatorias que produce manifestaciones similares a las presentadas en enfermedades autoinmunes como la enfermedad de Kawasaki. Se le ha denominado síndrome inflamatorio multisistémico en niños asociado temporalmente con SARS-CoV-2, el cual en muchos casos precisa internación en unidades de cuidados intensivos pediátricos y el manejo multidisciplinario por diversas especialidades.

Kawasaki Disease and Vaccination: Prospective Case-Control and Case-Crossover Studies among Infants in Japan

The causal effects of vaccines on Kawasaki disease (KD) remain elusive. We aimed to examine the association between vaccines administered during infancy and the development of KD in Japan. We conducted a multicenter prospective case-control study using questionnaires and compared the vaccination status of infants (age: 6 weeks to 9 months) who developed KD (KD group; n = 102) and those who did not develop KD (non-KD group; n = 139). Next, we performed a case-crossover study of 98 cases in the KD group and compared the status of vaccinations between the case and control periods. We also compared the incidence of KD in children for each 5-year period before and after the addition of new vaccines (2012–2013) using data from the Nationwide Survey of KD. In the case-control study, the vaccination status of the KD and control groups did not differ to a statistically significant extent. Multivariable analysis of the vaccination status and patient backgrounds showed no significant association between vaccination and KD development. In the case-crossover study, the status of vaccinations during the case and control periods did not differ to a statistically significant extent. In the analysis of data from the Nationwide Survey of KD, the incidence of KD in children of ages subject to frequent vaccination showed no significant increases in the latter five years, 2014–2018. Based on these prospective analyses, we confirmed that vaccination in early infancy did not affect the risk of KD.

Five immune-gene-signatures participate in the development and pathogenesis of Kawasaki disease

Objective

To screen for immune genes that play a major role in Kawasaki disease and to investigate the pathogenesis of Kawasaki disease through bioinformatics analysis.

Methods

Kawasaki disease‐related datasets GSE18606, GSE68004, and GSE73461 were downloaded from the Gene Expression Omnibus database. Three microarrays were integrated and standardized to include 173 Kawasaki disease samples and 101 normal samples. The samples were analyzed using CIBERSORT to obtain the infiltration of 22 immune cells and analyze the differential immune cells in the samples and correlations. The distribution of the samples was analyzed using principal component analysis (PCA). Immune‐related genes were downloaded, extracted from the screened samples and analyzed for differential analysis (different expression genes [DEG]) and weighted gene co‐expression network analysis (WGCNA). We constructed coexpression networks, and used the cytohobbe tool in Cytoscape to analyze the coexpression networks and select the immune genes that played a key role in them.

Results

Immune cell infiltration analysis showed that B cells naive, T cells CD8, natural killer (NK) cells activated, and so forth were highly expressed in normal samples. T cells CD4 memory activated, monocytes, neutrophils, and so forth were highly expressed in Kawasaki disease samples. PCA results showed a significant difference in the distribution of normal and Kawasaki disease samples. From the screened samples, 97 upregulated and 103 downregulated immune‐related genes were extracted. WGCNA analysis of DEG yielded 10 gene modules, of which the three most relevant to Kawasaki disease were red, yellow, and gray modules. They were associated with cytokine regulation, T‐cell activation, presentation of T‐cell receptor signaling pathways, and NK cell‐mediated cytotoxicity. CXCL8, CCL5, CCR7, CXCR3, and CCR1 were identified as key genes by constructing a coexpression network.

Conclusion

Our study shows that we can distinguish normal samples from Kawasaki disease samples based on the infiltration of immune cells, and that CXCL8, CCL5, CCR7, CXCR3, and CCR1 may play important roles in the development of Kawasaki disease.

The Platelet microRNA Profile of Kawasaki Disease: Identification of Novel Diagnostic Biomarkers

Challenging diagnosis and unknown etiology of Kawasaki disease (KD) increase the coronary artery lesions incidence. microRNAs (miRNAs) are the most promising biomarkers because of their stability in peripheral blood and noninvasive measurement procedure, whose potential utility have been proved in cancers. To explore the utility of differentially expressed (DE) miRNAs as early diagnostic markers, 44 patients (25 incomplete KD and 19 complete KD) and 31 febrile controls were recruited for small RNA sequencing. From all the 1922 expressed miRNA, 210 DE miRNAs were found between KD and febrile control groups. Though platelet miRNA profiles of complete KD incomplete KD were much similar through cluster analysis, the DE miRNAs were not identical. Eight DE miRNAs were validated by real-time quantitative PCR (qRT-PCR) in complete or incomplete KD groups using a normalizer, miR-126-3p, which was identified by geNorm and NormFinder tools. The expression level of miRNAs continuous changed over time was observed and the function analysis showed the potential role of miRNAs as therapeutic biomarkers. Additionally, the prediction model for KD showed a sensitivity of 78.8% and a specificity of 71.4%, respectively. This study used small RNA sequencing to identify miRNA biomarkers KD diagnosis based on a large sample size. Our findings shine a light on the understanding of molecular pathogenesis of KD and may improve the accuracy of KD diagnosis and prognosis in clinical.

Clinical characteristics of Kawasaki disease complicated with Mycoplasma pneumoniae pneumonia: A retrospective study

This study aimed to investigate the inner linkage and mechanism of Mycoplasma pneumoniae (MP) infection and Kawasaki disease (KD), as well as the risk factors of outcome in this cohort of patients.A retrospective study was performed in 210 patients diagnosed with KD complicated with community acquired pneumonia (CAP) in Children's Hospital, Zhejiang University School of Medicine from January 2014 to December 2017. They were divided into two groups based on MP infection: MP infection group (n = 97) and non-MP infection group (n = 113). We compared the variables of these two groups based on medical records.The MP infection group had higher ESR than the non-MP infection group. During hospitalization, the non-MP infection group had higher levels of WBC during hospital, LDH, PCT, and lower HB when compared to the MP infection group. No differences were found in the hs-CRP level, N%, PLT, ALT, CKMB, and cytokine levels (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) between MP and non-MP infection group. Likewise, no difference was found in fever duration or hospital stays between them. Totally 19 patients in the infection group had CAA with a rate of 19.59%; and 27 (23.89%) patients had CAA in the non-MP infection group. Unfortunately, no difference was found in CAA rate between the two groups.MP infection may occur simultaneously in children with Kawasaki disease. KD patients with MP infection tended to occur in older population. MP infection may not increase the risk of CAA, which still needs further large-scaled studies to confirm. Clinicians should be alert to KD patients with high level of ESR. MP should be screened and early treatment with macrolides should be given timely.

A comparison of serum IL6 and CRP levels with respect to coronary changes and treatment response in Kawasaki disease patients: a prospective study

To evaluate serum levels of IL6 in patients with Kawasaki disease and compare it with CRP, and to assess the role of these biomarkers in predicting coronary changes and resistance to the first-line therapy of this disease in a subset of Indian population. A single centre prospective observational study was conducted amongst all Kawasaki disease patients for a period of 18 months from January 2017 at Institute of Child Health, Kolkata. Serum IL6 and CRP were compared at diagnosis and after 48 h of administering IVIG in patients who developed coronary changes with those who did not and also among the responders and non-responders to IVIG, the first-line therapy given to these patients. Out of total 72 patients of KD [mean age of presentation: 24 months, M:F = 1.22:1], 30% (n = 22) had coronary artery involvement (CALs), and 15% (n = 11) were IVIG non-responders. Mean IL6 prior to IVIG in those with CALs was 143.60 pg/ml, which was about three times higher than in those without CALs (mean = 52.90 pg/ml), the difference being significant (p < 0.01). Mean CRP values also were significantly raised in patients with CALs (p < 0.01) whereas post-IVIG levels of mean serum IL6 was found to be 108.15 pg/ml in non-responders which was about 17 times raised than that in the responders (mean IL6 = 6.22),the difference again was statistically significant (p < 0.001).Also, ROC analysis revealed a sensitivity and specificity of 81.0% and 82.0%, respectively, for IL6; 72% and 74%, respectively, for CRP for predicting CALs. This study also shows a sensitivity of 72% and specificity of 68% for IL6 in predicting IVIG resistance whereas that of CRP being 90% sensitive and 36% specific. These results suggest that higher levels of IL-6 and CRP at diagnosis are associated with occurrence of CALs and IVIG resistance in KD patients. Using the cutoff for IL6 and CRP from our study, chances of developing CALs and IVIG resistance can be predicted, which might prevent the development of future complications like aneurysms in such patients.

Augmented ILT3/LILRB4 Expression of Peripheral Blood Antibody Secreting Cells in the Acute Phase of Kawasaki Disease

BACKGROUND

Kawasaki disease (KD) is an acute, systemic vasculitis syndrome that occurs in children. The clinical symptoms and epidemiologic features of KD strongly suggest that KD is triggered by unidentified infectious agents in genetically predisposed patients. In addition, a number of studies have described the role of B cells in the development of KD. To obtain a mechanistic insight into the humoral immune response of B-lineage cells in KD patients, we examined peripheral blood antibody secreting cells (ASCs) and inhibitory immunoreceptors, immunoglobulin-like transcript (ILT)/leukocyte immunoglobulin-like receptor (LILR), on each B cell subpopulation.

METHODS

Eighteen Japanese KD patients and thirteen healthy control subjects were recruited for this study. Their peripheral blood mononuclear cells were examined by flow cytometry for the number of CD19 B cells, the size of each B cell subset and the expression of the inhibitory isoforms of ILT/LILR on the B cell subset.

RESULTS

The frequency of CD19CD27 ASCs was significantly increased in the acute phase of KD and reduced after high-dose intravenous immunoglobulin (IVIG) treatment. Interestingly, while ILT2/LILRB1 expression was ubiquitously observed on every B cell/ASCs subset and the level was not significantly different after IVIG, ILT3/LILRB4 (B4) was uniquely expressed on only ASCs, and its expression was significantly decreased after IVIG.

CONCLUSIONS

In the acute phase of KD, the frequency of ASCs is high with augmented B4 expression, whereas it is lower with decreased B4 expression after IVIG. Further studies of B4 expression on ASCs in autoimmune and infectious diseases will be needed to confirm the significance of our findings.

Kawasaki disease among Egyptian children: A case series

Kawasaki disease is an acute vasculitis of early childhood. Its incidence varies among different ethnic groups with higher rates among Asians. In this case series, we presented four cases of Kawasaki disease with incomplete or atypical presentations in Egyptian children.

Two cases presented with meningitis, which is not a criteria for the diagnosis of Kawasaki disease. The other two cases presented with pharyngitis and fever, which did not respond to antibiotics. The clinical criteria for diagnosis of Kawasaki disease were either incomplete or appeared sequentially. Coronary artery aneurysms were detected in one case, while the others had normal coronary by echocardiography. All cases were followed in our clinic, according to international guidelines.

Early diagnosis and management of Kawasaki disease are important to ensure a good outcome and a high index of suspicion in febrile children is required irrespective of the clinical presentation.

Abnormalities of the Coronary Arteries in Children: Looking beyond the Origins

Coronary arterial abnormalities are uncommon findings in children that have profound clinical implications. Although anomalies of the coronary origins are well described, there are many other disease processes that affect the coronary arteries. Immune system-mediated diseases (eg, Kawasaki disease, polyarteritis nodosa, and other vasculiditides) can result in coronary arterial aneurysms, strictures, and abnormal tapering of the vessels. Because findings at imaging are an important component of diagnosis in these diseases, the radiologist's understanding of them is essential. Congenital anomalies may present at varying ages, and findings in hemodynamically significant anomalies, such as fistulas, are key for both diagnosis and preoperative planning. Pediatric heart surgery can result in wide-ranging postoperative imaging appearances of the coronary arteries and also predisposes patients to a multitude of complications affecting the heart and coronary arteries. In addition, although rare, accidental trauma can lead to injury of the coronary arteries, and awareness and detection of these conditions are important for diagnosis in the acute setting. Patients with coronary arterial conditions at presentation may range from being asymptomatic to having findings of myocardial infarction. Recognition of the imaging findings is essential to direct appropriate treatment. ^©RSNA, 2017.

Kawasaki disease: a matter of innate immunity

Kawasaki disease (KD) is an acute systemic vasculitis of childhood that does not have a known cause or aetiology. The epidemiological features (existence of epidemics, community outbreaks and seasonality), unique age distribution and clinical symptoms and signs of KD suggest that the disease is caused by one or more infectious environmental triggers. However, KD is not transmitted person-to-person and does not occur in clusters within households, schools or nurseries. KD is a self-limited illness that is not associated with the production of autoantibodies or the deposition of immune complexes, and it rarely recurs. Regarding the underlying pathophysiology of KD, innate immune activity (the inflammasome) is believed to play a role in the development of KD vasculitis, based on the results of studies with animal models and the clinical and laboratory findings of KD patients. Animal studies have demonstrated that innate immune pathogen-associated molecular patterns (PAMPs) can cause vasculitis independently of acquired immunity and have provided valuable insights regarding the underlying mechanisms of this phenomenon. To validate this concept, we recently searched for KD-specific PAMPs and identified such molecules with high specificity and sensitivity. These molecules have structures similar to those of microbe-associated molecular patterns (MAMPs), as shown by liquid chromatography-tandem mass spectrometry. We propose herein that KD is an innate immune disorder resulting from the exposure of a genetically predisposed individual to microbe-derived innate immune stimulants and that it is not a typical infectious disease.

Novel Echocardiographic Indices for Assessing the Left Main Coronary Artery in Children With Kawasaki Disease

BACKGROUND

Kawasaki disease (KD) is the most common cause of acquired myocardial infarction in children. Coronary artery involvement is the most serious feature of this vasculitis syndrome. Timely diagnosis of coronary artery involvement is of utmost importance since it can prevent long-term morbidity and mortality. The current methods for the diagnosis of coronary artery dilation in KD are inconsistent and are also not capable of detecting all the abnormal coronary arteries or the so-called occult dilations present.

OBJECTIVES

The aim of this study was to determine the sensitivity and specificity of three novel allometric indices for the diagnosis of left main coronary artery (LMCA) involvement in KD.

METHODS

We performed a prospective case-control study in 69 children (38 with KD and 31 healthy children). All the followed up patients underwent two complete echocardiographic examinations at the time of admission and 4 - 6 weeks later. We measured the size of the LMCA, coronary sinus (CS) and aorta (A) and calculated the LMCA/CS, LMCA/A and LMCA/CS/A ratios. We also calculated the cut-off scores for each index using receiver operating characteristic curves both in the acute phase and 4 - 6 weeks later.

RESULTS

In the acute phase, the cut-off scores for the LMCA/A ratio was > 0.23; LMCA/CS, > 0.44; and LMCA/CS/A, > 0.03. This implied 60% sensitivity and 80% specificity for the detection of abnormal LMCA in KD. Four to six weeks after the acute phase, the LMCA/A cut-off score was > 0.23; LMCA/CS, > 0.73; and LMCA/CS/A, > 0.73. This implied 100% sensitivity and 100% specificity for the detection of abnormal LMCA. There was a significant decrease in the size of the CS in comparison with the control group (1.92 ± 0.363 mm; P = 0.007 and 0.023).

CONCLUSIONS

The LMCA/A, LMCA/CS and LMCA/CS/A ratios seem to provide simple and patient-specific indices for the detection of abnormal LMCA in KD, both in the acute and subacute phase. Further, a decrease in the size of the CS may imply a decrease in coronary artery flow in the acute and subacute phases of KD.

Clinical Characteristics of Kawasaki Disease in Infants Younger than Six Months: A Single-Center Study

BACKGROUND AND OBJECTIVES

Kawasaki disease (KD) is the leading cause of acquired heart disease, which predominantly occurs in children under the age of 5 years. However, there are fewer cases of KD in infants younger than 6 months, which makes it difficult to diagnose. We investigated the clinical manifestations of KD in this age group and compared them with those in the older age group.

SUBJECTS AND METHODS

We retrospectively reviewed the medical records of 239 patients with KD admitted to the Hallym Sacred Heart Hospital from January 2013 to June 2015. The data were categorized into 2 groups by age: Group A (≤6 months, n=26) and Group B (>6 months, n=213).

RESULTS

Group A had a longer hospitalization period than Group B (6.69 vs. 5.19 days, p=0.002). Group A had fewer clinical manifestations upon admission, due to which there was a higher incidence of incomplete KD (1.88 vs. 3.54 of the diagnostic criteria, p<0.05; and 19.2% vs. 4.2% incomplete KD incidence, p=0.002). The rate of cardiac complications was higher in Group A (30.8% vs. 11.7%, p=0.011).

CONCLUSION

The rate of cardiac complications of the patients younger than 6 months was significantly higher than that of the older patients. Therefore, infants younger than 6 months with unexplained fever for more than 5 days should be suspected as having KD, even if the principal clinical features are not fully presented. Echocardiography must be appropriately used for diagnosis of KD in suspected patients.

Two infants with tuberculid associated with Kawasaki disease

Bacille de Calmette et Guerin (BCG) is the only licensed tuberculosis vaccine to prevent severe tuberculosis. The adverse events of BCG vaccination, including local reactions, lymphadenitis, osteomyelitis, tuberculid, and disseminated infection, have been reported. Two infants presented erythema at the inoculation site of BCG after the resolution of Kawasaki disease (K_D). They received BCG vaccination 1 week and 6 weeks before the K_D onset, respectively. Intravenous immunoglobulin improved the K_D activity, however the skin rash of BCG inoculation site extended to the face and extremities days 24 and 10 after the K_D onset, respectively. Both bacteriological study and interferon-γ release assay were negative for Mycobacterium tuberculosis infection. These patients were diagnosed as having tuberculid after K_D. The skin lesions gradually disappeared without antibiotic therapy over 2 months. The development of tuberculid in these patients might be associated with the remnant immune activation of K_D.

Severe vitamin D deficiency in patients with Kawasaki disease: a potential role in the risk to develop heart vascular abnormalities?

Twenty-five-hydroxyvitamin D (25(OH)-vitamin D) is crucial in the regulation of immunologic processes, but-although its deficiency has been reported in patients with different rheumatological disorders-no data are available for Kawasaki disease (KD). The goals of this study were to assess the serum levels of 25(OH)-vitamin D in children with KD and evaluate the relationship with the eventual occurrence of KD-related vascular abnormalities. We evaluated serum 25(OH)-vitamin D levels in 79 children with KD (21 females, 58 males, median age 4.9 years, range 1.4-7.5 years) in comparison with healthy sex-/age-matched controls. A significantly higher percentage of KD patients (98.7 %) were shown to have reduced 25(OH)-vitamin D levels (<30 ng/mL) in comparison with controls (78.6 %, p < 0.0001). Furthermore, KD patients had severely low levels of 25(OH)-vitamin D than controls (9.17 ± 4.94 vs 23.3 ± 10.6 ng/mL, p < 0.0001), especially the subgroup who developed coronary artery abnormalities (4.92 ± 1.36 vs 9.41 ± 4.95 ng/mL, p < 0.0001). In addition, serum 25(OH)-vitamin D levels correlated not only with erythrosedimentation rate (p < 0.0001), C-reactive protein (p < 0.0001), hemoglobin level at KD diagnosis (p < 0.0001) but also with both coronary artery aneurysms (p = 0.005) and non-aneurysmatic cardiovascular lesions (p < 0.05). Low serum concentrations of 25(OH)-vitamin D might have a contributive role in the development of coronary artery complications observed in children with KD.

Bacillus Calmette-Guérin reactivation as a sign of incomplete Kawasaki disease

Kawasaki disease (KD) is an acute, self-limited, systemic vasculitis of unknown aetiology, extremely rare in infants younger than 6 months old. Younger infants are more likely to present with incomplete KD (IKD) and are at higher risk of developing coronary abnormalities. An early and specific clinical sign, not included in the classical diagnosis criteria, but that can be very useful in the diagnosis of KD, is the reaction at the Bacillus Calmette-Guérin (BCG) inoculation site. We describe a case of a 4-month-old boy, fully immunised, whose BCG scar reactivation led to the diagnosis of IKD. This case-report emphasises the importance of BCG site reactivation in establishing a diagnosis of IKD that clinicians should be aware of, especially in countries where BCG vaccination is still part of the immunisation schedule.

Pediatric vasculitis: recognizing multisystemic manifestations at body imaging

Pediatric vasculitides are multisystem diseases that can be diagnostic challenges because of variable clinical manifestations. The clinical manifestation is determined by the size of the affected vessels, organs involved, extent of vascular injury, and underlying pathologic characteristics. Henoch-Schönlein purpura and Kawasaki disease are the two most common subtypes of pediatric vasculitis. Diagnosis of pediatric vasculitis can be difficult, and the outcome can be serious or fatal in the absence of timely intervention. Imaging plays a central role in establishing the diagnosis of vasculitis involving large- and medium-sized vessels, visualizing its vascular and extravascular manifestations, and monitoring the disease course and response to treatment. Although imaging cannot depict the vessel changes of small-vessel vasculitis directly, it can be used to detect tissue damage resulting from vessel inflammation. This article discusses the classification and clinical features of the major pediatric vasculitides. The imaging approach to and nonneurologic findings of major pediatric vasculitis subtypes are reviewed for the pediatric body imager.

Vitamin D nutritional status and the risk for cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality. CVD has a significant impact on health care systems worldwide and over 23 million individuals are expected to succumb to the disease by 2030. Early onset of atherosclerosis in childhood along with other risk factors of CVD, including elevated circulating lipids, have been shown to persist in adulthood and lead to CVD. Vitamin D deficiency is considered a risk factor for the pathogenesis of CVD, with childhood nutritional status of vitamin D being an important determinant of the development of CVD. Low levels of 25-hydroxyvitamin D can arise due to reduced intake as well as geographical location, and other diseases/conditions such as chronic kidney disease and obesity. Childhood vitamin D deficiency can progress and lead to atherosclerosis and other CVDs in adulthood. Early intervention with vitamin D supplementation is an ideal approach towards preventive therapy. However, there is no clear consensus regarding the role of vitamin D in childhood CVD. In the present study, we reviewed the available evidence in favor of and against such a role for this vitamin.

The history and evolution of immunoglobulin products and their clinical indications

The history of providing antibodies to treat diseases began in the 19th century with the discovery of tetanus and diphtheria toxins and the demonstration that immunity to tetanus and diphtheria infections could be transferred by immune sera. Characterization of the mediators of this immunity resulted in the discovery that antibodies are proteins that can be isolated and used to protect against infectious diseases. Development of a method to isolate antibodies from human plasma that could be safely injected into people initiated the development of human gamma globulin preparations to provide antibodies to patients with inherited antibody deficiencies. To overcome the limitations imposed by intramuscular injection of gamma globulin, intravenous gamma globulin preparations were developed that began to be used in a wide variety of clinical conditions. Thus the original clinical indication for infection prevention was expanded to several other indications that employ large doses to suppress inflammatory and autoimmune disorders. The most recent development in immunoglobulin therapy is the production of concentrated immune globulins for subcutaneous injection. Home infusions of subcutaneous immunoglobulin are increasingly used to treat immunodeficient patients and are being studied for other clinical applications.

Recognising Kawasaki disease in UK primary care: a descriptive study using the Clinical Practice Research Datalink

BACKGROUND

Kawasaki disease is a rare childhood illness that can present non-specifically, making it a diagnostic challenge. The clinical presentation of Kawasaki disease has not been previously described in primary care.

AIM

To describe how children with an eventual diagnosis of Kawasaki disease initially present to primary care in the UK.

DESIGN AND SETTING

The Clinical Practice Research Datalink was used to find cases coded as Kawasaki disease. Hospital Episode Statistics, hospital admissions, and hospital outpatient attendances were used to identify the children with a convincing diagnosis of Kawasaki disease.

METHOD

Questionnaires and a request for copies of relevant hospital summaries, discharge letters, and reports were sent to GPs of the 104 children with a diagnosis of Kawasaki disease between 2007 and 2011.

RESULTS

Most children presented with few clinical features typical of Kawasaki disease. Of those with just one feature, a fever or a polymorphous rash were the most common. By the time that most children were admitted to hospital they had a more recognisable syndrome, with three or more clinical features diagnostic of Kawasaki disease. Most GPs did not consider Kawasaki disease among their differential diagnoses, but some GPs did suspect that the child's illness was unusual.

CONCLUSION

The study highlighted the difficulty of early diagnosis, with most children having a non-specific presentation to primary care. GPs are encouraged to implement good safety netting, and to keep Kawasaki disease in mind when children present with fever and rashes.

Profiles of responses of immunological factors to different subtypes of Kawasaki disease

Background

The responses of immunological factors to different subtypes of Kawasaki disease (KD) remain poorly understood.

Methods

We recruited 388 patients with KD, 160 patients with infectious febrile disease and 85 normal children who served as control subjects. Both the levels and percentages of T lymphocyte subsets, natural killer cells (NK cells) and B cells were analyzed via flow cytometry. The levels of serum IgG, IgM, IgA and C3, C4 were assessed via velocity scatter turbidimetry.

Results

The most significant differences noted between the patients with infectious febrile disease and the normal children were the elevated levels of B cells, C3 and the ratio of CD4/CD8, and the decreased levels of CD8+ T cells and NK cells, as well as the moderate increase in the absolute value of the CD3+ cells. The decreased T cell levels and the elevated B cell levels were helpful in distinguishing typical KD from atypical KD; the elevated T cell levels, the elevated NK cell and B cell levels and the decreased B cell levels were helpful in predicting the effectiveness of IVIG; low C3 and C4 levels were linked with prodromal infections.

Conclusions

Lymphocytes subsets and complement markers may be useful in differentiating among the different subtypes of KD and in helping clinicians understand the pathophysiology of KD.

Guideline-Concordant Treatment of Kawasaki Disease With Immunoglobulin and Aspirin and the Incidence of Coronary Artery Aneurysm

OBJECTIVE

Current guidelines for Kawasaki disease (KD) recommend intravenous immunoglobulin infusion and echocardiography. However, no previous studies have evaluated the relationship between the treating hospital's concordance with guidelines and the prevention of coronary artery aneurysm in patients with KD.

STUDY DESIGN

KD patients between 2010 and 2013 were identified in a Japanese national inpatient database. Guideline concordance was defined as the proportions of patients who received echocardiography as well as treatment with both immunoglobulin and aspirin, which were divided into quartiles. Multivariable logistic regression analysis was conducted to examine the association between the guideline concordance and the occurrence of coronary artery aneurysm with adjustment for patient backgrounds.

RESULTS

In sum, 20 156 patients with KD were identified. The very high (>83.3%) concordance group had a lower rate of coronary artery aneurysm than the very low (<59.0%) concordance group (4.9% vs 9.9%; odds ratio, 0.45; 95% CI, 0.27 to 0.74; P = .002).

CONCLUSION

All patients with KD should be treated according to the guidelines.

Early Appearance of Principal Symptoms of Kawasaki Disease is a Risk Factor for Intravenous Immunoglobulin Resistance

It is difficult to accurately predict treatment resistance in Kawasaki disease (KD). Patients considered to be low-risk cases often develop resistance to intravenous immunoglobulin (IVIG). We herein examined whether information from the clinical course of KD could improve the prediction accuracy of a previously reported risk score. We retrospectively reviewed the clinical records of 100 KD patients. The clinical characteristics and laboratory data were compared between IVIG-sensitive and IVIG-resistant patients and also between patients with and without coronary artery aneurysm (CAA). The total incidence of IVIG resistance and CAA development was 34 and 13 %, respectively. Multiple regression analysis identified the early appearance of principal symptoms (≤day 2 of the illness) as a risk factor for IVIG resistance (OR 2.88, 95 % CI 1.11-7.44, p = 0.0041), whereas delayed IVIG administration (≥day 6) (OR 2.23, 95 % CI 0.66-7.64, p = 0.018) and IVIG resistance (OR 9.05, 95 % CI 2.27-36.10, p = 0.015) were independent predictors for CAA development. The addition of the first appearance day of principal symptoms into a previously reported scoring system improved its prediction accuracy for IVIG resistance. KD patients who had presented with any principal symptoms within 2 days of fever onset were at a high risk for IVIG resistance regardless of previously reported risk score. A careful medical history-taking that is focused on the clinical course enables a better prediction of IVIG resistance.

Extensive cervical lymphadenitis mimicking bacterial adenitis as the first presentation of Kawasaki disease

Cervical adenitis >1.5cm in diameter is the less frequently observed criteria in patients with Kawasaki disease and it is usually found in association with other symptoms during the acute phase. Moreover, the finding of fever and lymphadenitis with intense local signs of inflammation and phlegmon is rarely seen as the initial manifestation of Kawasaki disease. We report the case of a 7-year-old boy who had cervical lymphadenitis with adjacent cellulitis and phlegmon mimicking bacterial adenitis as the first presentation of Kawasaki disease. The patient had fever, cervical lymphadenitis with adjacent cellulitis, and severe headache. Cefadroxil was prescribed based on the clinical diagnosis of bacterial adenitis. Because he remained febrile and phlogistic signs worsened, after 1 day of hospitalization, antibiotics were administrated intravenously (ceftriaxone and oxacillin). The computed tomography of the neck showed primary infectious/inflammatory process. On the fourth day, the patient had dry and scaly lips, and treatment with oxacillin was replaced by clindamycin because the patient was still febrile. On the ninth day, he presented non-exudative bilateral conjunctival injection. On the tenth day of febrile disease, a rash appeared on his trunk, hands and feet. Patient's symptoms resolved after intravenous administration of immunoglobulin (2g/kg/dose), and he was discharged 2 days later. On the 14th day, the patient had lamellar desquamation of fingers. Kawasaki disease should be considered as a differential diagnosis in children with febrile cervical lymphadenitis unresponsive to empiric antibiotics even if they have adjacent cellulitis and phlegmon.

Kawasaki Disease

Kawasaki disease (KD) is a systemic vasculitis mainly affecting children below 5 years of age. Diagnosis is made upon a combination of criteria, including persistent fever; edema, erythema, or desquamation of the extremities; polymorphous exanthema; conjunctival injection; erythema of the lips and oral mucosa; and lymphadenopathies. Many cases do not meet all diagnostic criteria but should also be considered for therapy. IVIG and aspirin are the main therapeutic measures.

Timing of intravenous immunoglobulin treatment and risk of coronary artery abnormalities in children with Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is a type of febrile self-limiting systemic vasculitis, which affects the coronary arteries (CA) and may cause cardiac ischemia during childhood and adult life. Intravenous immunoglobulin (IVIG) has become the standard therapy for KD. However, it is still uncertain if CA outcome is associated with the timing of IVIG administration with reference to fever onset.

METHODS

The present study was designed to identify the risk for development and delay in resolution of CA abnormalities in association with IVIG administration within or after 10 days of KD onset. A retrospective analysis of clinical signs, laboratory data, and prospectively collected echocardiography (ECHO) results of 106 children hospitalized with KD was utilized.

RESULTS

IVIG was administered to 86 (81.1%) patients within 10 days, and 20 (18.9%) patients received the first dose of IVIG after 10 days of illness. Among 23 (21.6%) patients who were diagnosed with CA lesions, 18 had a CA abnormality at initial ECHO, whereas they appeared after IVIG therapy in five patients. The risk for CA lesions on initial ECHO was higher among the patients who were admitted after 10 days of disease onset [odds ratio (OR) = 5.3, 95% confidence interval (CI) = 1.7-15.9] but comparable with the post-IVIG treatment group (OR = 3.1, 95% CI = 0.48-19.8). The age <1 year and erythrocyte sedimentation rate (ESR) > 40 mm/hour were associated with non-resolution of CA lesions within 9 weeks of KD onset. Overall, 95.6% of children had resolution of CA abnormalities within 6 months of onset of KD symptoms.

CONCLUSION

The results of this study suggest that although IVIG treatment within 10 days is important to minimize development of cardiac pathology, neither occurrence of CA lesions in IVIG-treated children nor the time frame for resolution of established CA abnormalities was associated with the timing of IVIG administration. Age <1 year and high ESR (>40 mm/hour) predict a delay in resolution of CA lesions among children with KD.