Superantigens related to Kawasaki syndrome

Pneumonia in the presentation of Kawasaki disease: The syndrome or a sequence of two diseases?

Two cases of Kawasaki disease (KD) presented as persistent lung consolidation associated with Group A Streptococcus and Influenza A co-infection, which resolved following intravenous immunoglobulin. Thus, pediatricians should consider the diagnosis of KD in the presence of pneumonia that is nonresponsive to antibiotic therapy with prolonged fever and inflammatory reactions.

Pulmonary presentation of Kawasaki disease-A diagnostic challenge

OBJECTIVES

Kawasaki disease (KD) is a multisystemic vasculitis with predominant mucocutaneous manifestations. Pulmonary involvement in KD is distinctly uncommon and is not commonly recognized. We describe our experience of managing children with KD wherein the initial presentation was predominantly pulmonary.

METHODS

Six hundred and two children have been diagnosed with KD during the period January 1993 to May 2017 in the Allergy Immunology Unit, Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh. Data were collected from inpatient records in Allergy Immunology Unit and follow-up files in the Pediatric Rheumatology Clinic.

RESULTS

Of 602 children, 11 (1.83%) had a predominant pulmonary presentation of KD. Mean age at diagnosis of KD was 2.5 years. Fever, cough and respiratory distress were the presenting complaints in all patients. First sign of KD was noted at a mean duration of 14.5 days from the onset of symptoms. Periungual desquamation was the most common clinical sign (72.7%). Persistent fever in spite of antimicrobials, thrombocytosis, and elevated erythrocyte sedimentation rate and C-reactive protein levels pointed toward a diagnosis of KD in our patients. Parenchymal consolidation was evident on chest X-ray in all patients, pleural effusion in six, empyema in three, and pneumothorax in two patients. Coronary artery abnormalities were evident in three patients. Intravenous immunoglobulin was given after a mean period of 22.4 days of onset of fever.

CONCLUSIONS

The diagnosis of KD is often delayed in children who have a predominantly pulmonary presentation. This can have adverse clinical consequences.

An Unexpected Fever Post Serogroup B Meningococcal Sepsis

This case report describes an invasive meningococcal group B infection followed by the development of Kawasaki disease (KD) complicated by macrophage activation syndrome (MAS) in a 2-year-old child. The presented case indicates the possible etiologic relationship between meningococcal sepsis and KD as support of bacterial toxin induced theory. It's important to maintain a high grade of suspicious for KD in every relapse of fever also during convalescence phase of severe infection. Usually, initial treatment with intravenous immunoglobulin is sufficient to control the disease; but, in case of refractory KD complicated by MAS, corticosteroid therapy represents a good option inducing prompt fever resolution and clinical improvement.

Kawasaki disease for dermatologists

Kawasaki disease (KD) is a systemic vasculitis that mostly affects children below the age of 5. The vasculitis involves arteries of medium size, especially the coronaries. Various etiologies have been proposed including association with micro-organisms, bacterial superantigens, and genetic factors, however, the exact cause remains unknown. There is no specific laboratory test for KD. Diagnosis is clinical and depends upon the presence of fever for ≥5 days and 4 or more of five principal features, viz. polymorphous exanthem, extremity changes, mucosal changes involving the lips and oral cavity, bilateral bulbar conjunctival injection, and unilateral cervical lymphadenopathy. The term "incomplete KD" refers to the presence of fever and less than four principal clinical features. Recognition of this group of patients is important because it is usually seen in infants and risk of coronary abnormalities is increased probably because of delays in diagnosis. However, what appears to be "incomplete" at a given point of time may not actually be so because some of the features may have already subsided and others may evolve over time. Hence, a detailed dermatological examination is warranted in all cases, especially in incomplete KD, to ensure timely diagnosis. Although KD is a self-limiting disease in most patients, coronary artery abnormalities (CAAs) including coronary dilatations and aneurysms may develop in up to 25% of untreated patients. CAAs are the most common cause of morbidity and mortality in patients with KD. Treatment is aimed at reducing inflammation and consists of intravenous immunoglobulin (IVIG) along with aspirin. Despite treatment, some patients may still develop CAAs, and hence, long-term follow up is of utmost importance.

Diagnosis, treatment, and long-term management of Kawasaki disease: a statement for health professionals from the Committee on Rheumatic Fever, Endocarditis and Kawasaki Disease, Council on Cardiovascular Disease in the Young, American Heart Association

BACKGROUND

Kawasaki disease is an acute self-limited vasculitis of childhood that is characterized by fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy. Coronary artery aneurysms or ectasia develop in approximately 15% to 25% of untreated children and may lead to ischemic heart disease or sudden death.

METHODS AND RESULTS

A multidisciplinary committee of experts was convened to revise the American Heart Association recommendations for diagnosis, treatment, and long-term management of Kawasaki disease. The writing group proposes a new algorithm to aid clinicians in deciding which children with fever for > or =5 days and < or =4 classic criteria should undergo echocardiography, receive intravenous gamma globulin (IVIG) treatment, or both for Kawasaki disease. The writing group reviews the available data regarding the initial treatment for children with acute Kawasaki disease, as well for those who have persistent or recrudescent fever despite initial therapy with IVIG, including IVIG retreatment and treatment with corticosteroids, tumor necrosis factor-alpha antagonists, and abciximab. Long-term management of patients with Kawasaki disease is tailored to the degree of coronary involvement; recommendations regarding antiplatelet and anticoagulant therapy, physical activity, follow-up assessment, and the appropriate diagnostic procedures to evaluate cardiac disease are classified according to risk strata.

CONCLUSIONS

Recommendations for the initial evaluation, treatment in the acute phase, and long-term management of patients with Kawasaki disease are intended to assist physicians in understanding the range of acceptable approaches for caring for patients with Kawasaki disease. The ultimate decisions for case management must be made by physicians in light of the particular conditions presented by individual patients.

Diagnosis, treatment, and long-term management of Kawasaki disease: a statement for health professionals from the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young, American Heart Association

BACKGROUND

Kawasaki disease is an acute self-limited vasculitis of childhood that is characterized by fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy. Coronary artery aneurysms or ectasia develop in approximately 15% to 25% of untreated children and may lead to ischemic heart disease or sudden death.

METHODS AND RESULTS

A multidisciplinary committee of experts was convened to revise the American Heart Association recommendations for diagnosis, treatment, and long-term management of Kawasaki disease. The writing group proposes a new algorithm to aid clinicians in deciding which children with fever for > or =5 days and < or =4 classic criteria should undergo echocardiography [correction], receive intravenous gamma globulin (IVIG) treatment, or both for Kawasaki disease. The writing group reviews the available data regarding the initial treatment for children with acute Kawasaki disease, as well for those who have persistent or recrudescent fever despite initial therapy with IVIG, including IVIG retreatment and treatment with corticosteroids, tumor necrosis factor-alpha antagonists, and abciximab. Long-term management of patients with Kawasaki disease is tailored to the degree of coronary involvement; recommendations regarding antiplatelet and anticoagulant therapy, physical activity, follow-up assessment, and the appropriate diagnostic procedures to evaluate cardiac disease are classified according to risk strata.

CONCLUSIONS

Recommendations for the initial evaluation, treatment in the acute phase, and long-term management of patients with Kawasaki disease are intended to assist physicians in understanding the range of acceptable approaches for caring for patients with Kawasaki disease. The ultimate decisions for case management must be made by physicians in light of the particular conditions presented by individual patients.

Kawasaki disease

PURPOSE OF REVIEW

Kawasaki disease is an acute, self-limited vasculitis of childhood characterized by fever, bilateral nonexudative conjunctivitis, erythema of the lips and oral mucosa, changes in the extremities, rash, and cervical lymphadenopathy. Coronary artery aneurysms or ectasia develop in approximately 15 to 25% of untreated children with the disease and may lead to myocardial infarction, sudden death, or ischemic heart disease.

RECENT FINDINGS

In the United States, Kawasaki disease has now surpassed acute rheumatic fever as the leading cause of acquired heart disease in children. The cause of Kawasaki disease remains unknown, but fortunately intravenous immune globulin therapy has proved to be effective at reducing the prevalence of coronary aneurysms in most children treated in the acute phase. Therapy for Kawasaki disease resistant to intravenous immune globulin therapy is an area of research and controversy. The long-term treatment of children with Kawasaki disease is dependent on coronary artery status.

SUMMARY

This review covers key data on the etiology, pathogenesis, treatment, and long-term outcomes of Kawasaki disease, highlighting recent publications.

Kawasaki disease

Kawasaki disease is a leading cause of acquired heart disease in children in the USA. An acute vasculitis of unknown etiology, it occurs predominantly in infancy and early childhood, and more rarely in teenagers. Coronary artery aneurysms or ectasia develop in approximately 15-25% of children with the disease. Treatment with intravenous gamma globulin, 2 g per kg, in the acute phase reduces this risk three- to fivefold. Angiographic resolution occurs in approximately one-half of aneurysmal arterial segments, but these show persistent histologic and functional abnormalities. The remainder continue to be aneurysmal, often with development of progressive stenosis or occlusion. The worst prognosis occurs in children with so-called 'giant aneurysms', i.e. those with a maximum diameter greater than 8 mm, because thrombosis is promoted both by sluggish blood flow within the massively dilated vascular space and by the frequent development of stenotic lesions. Serial stress tests with myocardial imaging are mandatory in the management of patients with Kawasaki disease and significant coronary artery disease to determine the need for coronary angiography and transcatheter interventions or coronary bypass surgery. Continued long-term surveillance in patients with and without detected coronary abnormalities is necessary to determine the natural history of Kawasaki disease.

Endothelial cells expressing an inflammatory phenotype are lysed by superantigen-targeted cytotoxic T cells

The objective of this study was to investigate whether the superantigen staphylococcal enterotoxin A (SEA), which binds to HLA class II and T-cell receptor Vbeta chains, can direct cytotoxic T cells to lyse cytokine-stimulated endothelial cells (EC). In addition, we wanted to determine whether SEA-primed cytotoxic T cells could be targeted to EC surface molecules as a means of a novel cancer immunotherapy. Human umbilical vein EC (HUVEC), dermal microvascular EC (HMVEC), or the EC line EA.hy926 stimulated with gamma interferon (IFN-gamma) or tumor necrosis factor alpha (TNF-alpha) displayed upregulated HLA class II and adhesion molecule (CD54 and CD106) expression, respectively. SEA-primed T cells induced a strong cytotoxicity against IFN-gamma- and TNF-alpha-activated EA.hy926 which had been preincubated with SEA. Blocking of CD54 completely abrogated the T-cell attack. SEA-D227A, which has a mutated class II binding site, did not promote any cytotoxicity. A strong lysis was observed when a fusion protein consisting of protein A and SEA-D227A was added together with T cells to TNF-alpha-induced EA.hy926 and HUVEC precoated with monoclonal antibodies (MAb) directed against HLA class I, CD54, or CD106 molecules. Finally, an scFv antibody fragment reactive with an unknown EC antigen was fused with SEA-D227A. Both EA.hy926 and HMVEC were efficiently lysed by scFv-SEA-D227A-triggered cytotoxic T cells. Taken together, superantigen-activated T-cell-dependent EC killing was induced when EC expressed an inflammatory phenotype. Moreover, specific MAb targeting of the superantigen to surface antigens induced EC lysis. Our data suggest that directed T-cell-mediated lysis of unwanted proliferating EC, such as those in the tumor microvasculature, can be clinically useful.