Kiminori Masuda

Increased Serum Levels of Vascular Endothelial Growth Factor in Kawasaki Disease

Vascular endothelial growth factor (VEGF) is an angiogenic mitogen that specifically targets vascular endothelial cells. The objective of this study was to evaluate the role of VEGF in Kawasaki disease (KD), the most common cause of systemic vasculitis in childhood. Serum VEGF levels were measured by ELISA in 22 patients with KD, 22 febrile children with infection, and 19 healthy children. Samples from KD patients were divided into three groups: acute stage (n = 20), subacute stage (n = 13), and convalescent stage (n = 15). The results showed that KD patients in the acute and subacute stages had significantly higher levels of VEGF than did patients with infectious diseases and the healthy control subjects. When compared with the VEGF levels of patients with and without coronary artery lesions (CAL), significantly higher levels of VEGF were observed in the subacute stage in patients with CAL and in patients without CAL in the acute stage. Serial examination revealed that the serum VEGF levels in KD patients with CAL increased from a relatively low level in the acute stage to an extremely high level in the subacute stage. In contrast, patients without CAL were found to have extremely high levels of VEGF only in the acute stage of KD. In KD patients, the serum VEGF levels did not correlate with the inflammatory markers and clinical symptoms. Our results raise the possibility that VEGF is involved in the pathogenesis of KD, especially in the development of CAL. Further study is needed to clarify the biologic effect of VEGF on coronary arteries in KD.

Maternal Antibody against Toxic Shock Syndrome Toxin-1 May Protect Infants Younger than 6 Months of Age from Developing Kawasaki Syndrome

The symptoms of Kawasaki syndrome (KS) suggest a possible relationship between KS and superantigen(s). The infrequent occurrence of KS among young infants may be due to a passive maternal antibody. We investigated the antibody titers for superantigens (toxic shock syndrome toxin [TSST]-1, staphylococcal exotoxin B, and streptococcal pyrogenic exotoxins C and A) in 15 patients with KS who were <6 months of age prior to gamma globulin therapy and in 10 mothers of patients with KS <6 months of age. Significant findings were observed for only TSST-1 among the 4 anti-superantigens. The proportion of patients with KS who had high anti-TSST-1 titers was significantly higher than that among infant control subjects (33% vs. 5%, respectively; P=.031). The mean anti-TSST-1 titer for the mothers was significantly lower than that of adult control subjects (P=.021). Among infants <6 months of age, TSST-1 may be related to KS, and a maternal antibody may protect infants from developing KS.

A Severe Form of Kawasaki Disease Presenting with Only Fever and Cervical Lymphadenopathy at Admission

OBJECTIVE To examine the characteristics of patients with Kawasaki disease (KD) presenting with only fever and cervical lymphadenopathy at admission. STUDY DESIGN The laboratory and clinical findings of patients with definite KD presenting with only fever and cervical lymphadenopathy at admission (KDiL) were compared with those of all other patients with KD. RESULTS Sixteen patients with KDiL (8.6%) and 171 patients without KDiL were examined. The patients with KDiL were significantly older (KDiL/non-KDiL: 4.9+/-2.5/2.2+/-1.9 years) and admitted earlier (3.0+/-1.2/3.9+/-1.3 days of illness) than the patients without KDiL. They also showed significantly elevated white blood cell counts and C-reactive protein levels. Patients with KDiL were treated with the same dose of intravenous immunoglobulin as the patients without KDiL but were treated slightly later and had significantly higher frequency of additional intravenous immunoglobulin treatment (38%/10%) and coronary artery abnormalities (25%/5%). After adjustment for age, white blood cell count, and day of illness at admission or first intravenous immunoglobulin administration, the presence of KDiL significantly increased the risk of being a nonresponder to IVIG treatment or development of a coronary artery abnormality. CONCLUSIONS KDiL indicates a severe form of KD associated with increased risks of additional intravenous immunoglobulin treatment and coronary artery abnormalities. Patients with KDiL may require heightened surveillance and more aggressive treatment.

Possible relationship between streptococcal pyrogenic exotoxin A and Kawasaki syndrome in patients older than six months of age.

Background. We previously investigated antibody titers against four kinds of superantigens [streptococcal pyrogenic exotoxin A (SPEA), streptococcal pyrogenic exotoxin C, toxic shock syndrome toxin-1 and staphylococcal enterotoxin B] in patients with Kawasaki syndrome (KS) younger than 6 months of age and reported a relationship between toxic shock syndrome toxin-1 and KS patients. In this study we have investigated antibody titers in KS patients older than 6 months of age. Methods. Serum of 81 patients with KS older than 6 months of age, before intravenous gamma-globulin therapy, and 88 normal age-matched children were used in this study. The IgG antibody titers against four kinds of superantigens were measured with an enzyme-linked immunosorbent assay. Results. The KS patients showed significantly elevated mean SPEA titer (P = 0.006) and significantly higher incidence of high SPEA (P = 0.0024) compared with the controls. The SPEA titer in KS patients showed a significant positive correlation with the number of days from onset of illness (P = 0.0002). Conclusions. The elevated antibody titer against superantigens of KS patients older than 6 months of age was different from that of KS patients younger than 6 months of age. Our results suggest that KS patients’ exposure to SPEA occurred a few weeks before the onset of KS. SPEA may be one of the possible etiologic agents of KS among patients older than 6 months of age in Kagoshima, Japan.

Early diagnosis of Kawasaki disease in patients with cervical lymphadenopathy.

Background: Among typical patients with Kawasaki disease (KD), a few KD patients present with only fever and cervical lymphadenopathy at admission (KDL). These patients have a significant risk for misdiagnosis, delay in treatment for KD, and development of coronary artery abnormalities. Therefore, the development of an easy tool for early diagnosis in these patients is desirable.

Transient Low T Cell Response to Streptococcal Pyrogenic Exotoxin-C in Patients with Kawasaki Disease

Superantigens (SAs) are known to induce transient anergy followed by T cell activation. Recent reports have suggested that SAs are involved in the pathogenesis of Kawasaki disease (KD). In the present study, we investigated the peripheral T cell response to SAs by measuring proliferation and IL-2 production to determine whether the T cell anergy is induced by SAs in patients with KD. T cells were obtained from 45 Japanese patients with KD in different stages of the disease and were stimulated by streptococcal pyrogenic exotoxin (SPE)-A, SPE-C, and toxic shock syndrome toxin-1 (TSST-1). T cells from patients with KD in the acute or convalescent stage up to 2 mo showed significantly lower proliferation and IL-2 production than did T cells from healthy subjects stimulated by SPE-C, but not SPE-A or TSST-1. The T cell response to SPE-C normalized within 1 y. The low T cell response to SPE-C in the acute stage correlated with a peak platelet count and the C-reactive protein-positive period. These findings suggest that the transient low T cell response to SPE-C in patients with KD may have been related to SA-induced anergy or disappearance of SPE-C-responding cells from the circulation. The present results suggested that SPE-C may be involved in the pathogenesis of KD.

Patients diagnosed with Kawasaki disease before the fifth day of illness have a higher risk of coronary artery aneurysm

Background : A fever lasting for at least 5 days is an essential characteristic of the original diagnostic criteria ofKawasaki disease (KD). However, it is not difficult for an experienced physician to confirm the diagnosis of KD before the fifth day offever. The aim of this study is to investigate the effect of intravenous gamma globulin therapy (IVGG) in KD initiated before the fifth day of illness.

Twenty-five types of T-cell receptor Vβ family repertoire in patients with Kawasaki syndrome

Abstract Recently, a possible relationship between Kawasaki syndrome (KS) and superantigen has been discussed since the report of selective expansion of specific Vβ family in the acute phase of KS. To further investigate the relationship between KS and superantigens, we examined 25 types of T-cell receptor Vβ family repertoire in patients with KS using the reverse transcription polymerase chain reaction. This is the first attempt to examine all of 25 Vβ families in KS. A non radioisotope method was used to quantify mRNA so that the experiment was safer, simpler, and faster. An expression index (EI) for each Vβ was defined as: (the amount of each Vβ mRNA)/(the sum of all Vβ mRNA) × 100. Ten patients with KS and ten normal children were studied. The Vβ9 and Vβ15 of acute phase of KS showed both significantly lower mean EI and significantly higher frequency of a decreased EI value as compared with control children. Selective expansion of the Vβ family in the patients with KS was not observed. Although highly increased EIs were observed in various Vβs, their frequency was not statistically significant. The pattern of increased Vβs did not show the specific pattern that indicates a particular superantigen. Conclusion In Kawasaki syndrome non-radioisotope method for analysing Vβ mRNA is useful in cases where many samples have to be handled. The depletion of Vβ9 and Vβ15 or highly increased expression index in the acute phase of Kawasaki syndrome might suggest a relationship to superantigens.

An elevated value of high mobility group box 1 is a potential marker for poor response to high-dose of intravenous immunoglobulin treatment in patients with Kawasaki syndrome.

We examined the serum values of high mobility group box 1 (HMGB1) in 36 patients with Kawasaki syndrome (KS) (29 responders and 7 poor-responders to initial intravenous immunoglobulin treatment). A mean value of HMGB1 of poor-responders was significantly elevated compared with those of responders (P = 0.0042). Among the 6 factors showing significant differences between responders and poor-responders including HMGB1 (admission illness day, white blood cell counts, C-reactive protein, aspartate aminotransferase, lactate dehydrogenase), values of HMGB1 showed the widest area under the receiver operating characteristic curve. In conclusion, an elevated HMGB1 value could be a potential marker for poor-responders.

Serum Levels of Interleukin-18 Are Elevated in the Subacute Phase of Kawasaki Syndrome

Background: Elevations of various cytokines, including Th1 and Th2 cytokines, have been reported in the acute phase of Kawasaki syndrome (KS). As interleukin (IL)-18 plays an important role in the Th1 cell response, investigating the relevance of IL-18 in KS should be helpful in determining the pathophysiology of KS. Therefore, we examined the IL-18 values in KS. Methods: Serum IL-18 values were measured by an enzyme-linked immunosorbent assay. Samples were obtained from 41 patients in the acute and subacute phase of KS, 35 age-matched febrile controls and 13 afebrile controls. Results: No difference was observed in the values of white blood cell counts or C-reactive protein between acute-phase KS patients and febrile controls. On the contrary, acute-phase KS patients showed a significantly lower mean IL-18 value (398 ± 206 pg/ml) than that of febrile controls (584 ± 307 pg/ml) (p = 0.006). Subacute-phase KS patients showed a significantly elevated level of IL-18 (517 ± 276 pg/ml) compared to acute-phase patients (p = 0.0008). The IL-18 values in the subacute-phase patients showed a significant positive correlation with the duration of fever (r = 0.427, p = 0.0055) and also with the presence of coronary artery abnormalities (r = 0.332, p = 0.0340). The incidence of elevated IL-18 values in the subacute-phase patients was significantly higher than that in the afebrile controls (p = 0.048). Conclusions: Patients with KS showed normal IL-18 values in the acute phase and elevated values in the subacute phase. IL-18 pathways were activated in the subacute phase of KS, and subacute IL-18 values might be reflected in the severity of KS.