Mathematical Models of the Effect of Glucagon on Glycemia in Individuals With Type 2 Diabetes Treated With Dapagliflozin.

Context: Sodium-glucose cotransporter 2 (SGLT2) inhibitors lower blood glucose levels by promoting urinary glucose excretion, but their overall effects on hormonal and metabolic status remain unclear. Objective: We here investigated the roles of insulin and glucagon in the regulation of glycemia in individuals treated with an SGLT2 inhibitor using mathematical model analysis. Methods: Hyperinsulinemic-euglycemic clamp and oral glucose tolerance tests were performed in 68 individuals with type 2 diabetes treated with the SGLT2 inhibitor dapagliflozin. Data previously obtained from such tests in 120 subjects with various levels of glucose tolerance and not treated with an SGLT2 inhibitor were examined as a control. Mathematical models of the feedback loops connecting glucose and insulin (GI model) or glucose, insulin, and glucagon (GIG model) were generated. Results: Analysis with the GI model revealed that the disposition index/clearance, which is defined as the product of insulin sensitivity and insulin secretion divided by the square of insulin clearance and represents the glucose-handling ability of insulin, was significantly correlated with glycemia in subjects not taking an SGLT2 inhibitor but not in those taking dapagliflozin. Analysis with the GIG model revealed that a metric defined as the product of glucagon sensitivity and glucagon secretion divided by glucagon clearance (designated production index/clearance) was significantly correlated with blood glucose level in subjects treated with dapagliflozin. Conclusion: Treatment with an SGLT2 inhibitor alters the relation between insulin effect and blood glucose concentration, and glucagon effect may account for variation in glycemia among individuals treated with such drugs.

How Do Psychiatrists in Japan Choose Involuntary Admission, and What Do They Think of Supported Decision Making? A Thematic Analysis of Peer to Peer Interviews.

To include people with disabilities as equal citizens, CRPD (Convention on the Rights of Persons with Disabilities) promotes direct or supported decision-making by people with disabilities. However, involuntary psychiatry admission is considered in many countries to be necessary for people with psychosocial disabilities. To overcome the tension and implement CRPD, it is essential to understand the experiences and concerns of service users, family members, and medical professionals in each country. To understand the process and the factors that make psychiatrists decide involuntary psychiatric admission in Japan, and explore their attitudes toward direct or supported decision-making by people with psychosocial disabilities. Psychiatrists who had authorized involuntary admission and who were in charge of the service users were recruited at hospitals in Japan. The interviews were individual, peer to peer, and semi-structured. The interviews were audio-recorded, transcribed verbatim, and the analysis followed reflexive thematic analysis using NVIVO 12. Six psychiatrists (five designated psychiatrists and one psychiatric resident) participated in the study at two hospitals in urban Japan. The study found that the psychiatrists assessed symptoms, behaviors, and perceptions of the service users together with supports and wishes of their families. The psychiatrists decided on involuntary admission when they saw self-harm or violence, weak insights and judgment abilities, family's wishes, or when they wanted to avoid the service users leaving the hospital with incomplete treatment. The psychiatrists felt that the service users would not understand any explanations, which made their communications minimal. The psychiatrists thought it was hard to imagine a system other than the current involuntary admission mechanism. If it was to change, they felt the essential things were to avoid abuse, clarify who is responsible, make plans medically valid and feasible, and assess and plan through everyday life, not just in crisis. During a crisis, the psychiatrists were most careful about complying with the Mental Health Act and responded to the family's wish. The psychiatrists justified involuntary admission as they believed that people in a psychiatric crisis cannot decide or understand and need protection. Related protocols, laws, and expectations from family members shapes the values and practices of psychiatrists in Japan. The paper concludes with several recommendations to regard people with psychosocial disabilities as equal citizens, and promoting the aim of reducing or ending involuntary admission.

Successful coil embolization for pediatric internal mammary artery aneurysm after the Fontan procedure: A case report and literature review.

We herein describe the first pediatric case of an internal mammary artery (IMA) aneurysm caused by a median sternotomy. He was a 2-year-old with tricuspid atresia who underwent an extracardiac conduit Fontan procedure. On the 36th postoperative day, an asymptomatic left IMA aneurysm was detected via contrast computed tomography, which was successfully treated with coil embolization. The patient had no underlying disease such as vasculitis, connective tissue disease, or other hereditary diseases, and there were no episodes of infection or hypertension before or after the onset of the IMA aneurysm. Because the left IMA ran medially to the periphery and was in a vulnerable position during median sternotomy, we considered the IMA aneurysm was caused by the median sternotomy. We pediatric cardiologists should be aware that IMA aneurysms can occur in pediatric cardiac surgery, and we should be proactive in performing postoperative imaging studies in cases where the preoperative internal thoracic artery runs medially toward the periphery. Learning objective: Internal mammary artery (IMA) aneurysm is a rare vascular disease, especially in children. One-third of adult IMA aneurysms have been reported to be caused by sternotomy, but not in children. We report the first pediatric case of an IMA aneurysm caused by sternotomy. We should recognize that there is a potential risk of IMA aneurysms in pediatric cardiac surgery as well.

Metformin action in the gut-insight provided by [18F]FDG PET imaging.

Suppression of hepatic gluconeogenesis is thought to largely underlie the antidiabetes action of metformin. However, this drug also exerts various effects on the gut, one of which is the enhancement of the uptake of 18F-labeled fluorodeoxyglucose (FDG), a nonmetabolizable glucose derivative, during [18F]FDG positron emission tomography (PET)-computed tomography (CT). Whereas the relevance of this effect to the glucose-lowering action of metformin remains unclear, it is of special interest because it was discovered in humans. Cessation of metformin treatment for several days is required to normalize [18F]FDG uptake in the intestine, suggesting that the enhanced uptake is not a direct effect of the drug in the circulation but rather a prolonged secondary effect. A recent study with state-of-the-art PET-magnetic resonance imaging (MRI), which provides better tissue registration and soft-tissue contrast compared with PET-CT, revealed that metformin-induced accumulation of [18F]FDG occurs primarily in the lumen of the intestine, indicating that the drug promotes excretion of glucose from the circulation into this space. This phenomenon does not necessarily imply that metformin stimulates the removal of glucose from the body in the stool. Instead, it might be related to changes in the abundance and metabolism of the gut microbiota induced by metformin. Further studies of this effect of metformin might shed light on the unanswered questions that still remain concerning the clinical action of this old drug.

Relation of cardiac function to insulin resistance as evaluated by hyperinsulinemic-euglycemic clamp analysis in individuals with type 2 diabetes.

AIMS: Whereas homeostasis model assessment of insulin resistance (HOMA-IR), an easily measured but limited index of insulin resistance, has been shown to correlate with impairment of cardiac function in individuals without diabetes, the pathological relevance of insulin resistance to the development of cardiac dysfunction in individuals with type 2 diabetes has remained unclear. Here we investigated the relation between left ventricular (LV) function as assessed by echocardiography and insulin resistance as evaluated by hyperinsulinemic-euglycemic clamp analysis, the gold standard for measurement of this parameter, in individuals with type 2 diabetes. METHODS: This retrospective study included 34 individuals with type 2 diabetes who underwent both hyperinsulinemic-euglycemic clamp analysis and echocardiography. Both the insulin sensitivity index (ISI) as determined by glucose clamp analysis as well as HOMA-IR were determined as measures of insulin resistance. The ratio of the peak early- to late-diastolic mitral inflow velocities (E/A) and the LV ejection fraction (LVEF) were determined as measures of diastolic and systolic function, respectively. RESULTS: The ISI was significantly correlated with both the E/A ratio and LVEF (correlation coefficients of 0.480 and 0.360, respectively), whereas HOMA-IR was not correlated with either cardiac parameter. Multivariate analysis revealed that ISI was an independent predictor for both a high log [E/A] (P = 0.031) and a high LVEF (P = 0.045). CONCLUSIONS: Insulin resistance as evaluated by hyperinsulinemic-euglycemic clamp analysis may be causally related to LV diastolic and systolic dysfunction in individuals with type 2 diabetes.

Prednisolone Suppresses the Extracellular Release of HMGB-1 and Associated Inflammatory Pathways in Kawasaki Disease.

Innate immune activity plays an essential role in the development of Kawasaki disease (KD) vasculitis. Extracellular release of high mobility group box-1 (HMGB-1), an endogenous damage-associated molecular pattern protein that can activate the innate immune system and drive host inflammatory responses, may contribute to the development of coronary artery abnormalities in KD. Prednisolone (PSL) added to intravenous immunoglobulin treatment for acute KD may reduce such abnormalities. Here, we evaluate the dynamics of HMGB-1 and therapeutic effects of PSL on HMGB-1-mediated inflammatory pathways on KD vasculitis in vitro. Serum samples were collected prior to initial treatment from patients with KD, systemic juvenile idiopathic arthritis (sJIA), and from healthy controls (VH), then incubated with human coronary artery endothelial cells (HCAECs). Following treatment of KD serum-activated HCAECs with PSL or PBS as a control, effects on the HMGB-1 signaling pathway were evaluated. Compared to that from VH and sJIA, KD serum activation induced HCAEC cytotoxicity and triggered extracellular release of HMGB-1. KD serum-activated HCAECs up-regulated extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK) and, p38 phosphorylation in the cytoplasm and nuclear factor kappa B (NF-κB) phosphorylation in the nucleus and increased interleukin (IL)-1ß and tumor necrosis factor (TNF)-α production. PSL treatment of KD serum-activated HCAECs inhibited extracellular release of HMGB-1, down-regulated ERK1/2, JNK, p38, and NF-κB signaling pathways, and decreased IL-1ß and TNF-α production. Our findings suggest that extracellular HMGB-1 plays an important role in mediating KD pathogenesis and that PSL treatment during the acute phase of KD may ameliorate HMGB-1-mediated inflammatory responses in KD vasculitis.

Dose-dependent accumulation of glucose in the intestinal wall and lumen induced by metformin as revealed by 18 F-labelled fluorodeoxyglucose positron emission tomography-MRI.

AIM: To investigate the relationships between various clinical variables and the metformin-induced accumulation of fluorodeoxyglucose (FDG) in the intestine, with distinction between the intestinal wall and lumen, in individuals with type 2 diabetes who were receiving metformin treatment and underwent 18 F-labelled FDG ([18 F]FDG) positron emission tomography (PET)-MRI. MATERIALS AND METHODS: We evaluated intestinal accumulation of [18 F]FDG with both subjective (a five-point visual scale determined by two experienced radiologists) and objective analyses (measurement of the maximum standardized uptake value [SUVmax ]) in 26 individuals with type 2 diabetes who were receiving metformin and underwent [18 F]FDG PET-MRI. [18 F]FDG accumulation within the intestinal wall was discriminated from that in the lumen on the basis of SUVmax . RESULTS: SUVmax for the large intestine was correlated with blood glucose level (BG) and metformin dose, but not with age, body mass index, HbA1c level or estimated glomerular filtration rate (eGFR). SUVmax for the small intestine was not correlated with any of these variables. Visual scale analysis yielded essentially similar results. Metformin dose and eGFR were correlated with SUVmax for the wall and lumen of the large intestine, whereas BG was correlated with that for the wall. Multivariable analysis identified metformin dose as an explanatory factor for SUVmax in the wall and lumen of the large intestine after adjustment for potential confounders including BG and eGFR. CONCLUSIONS: Metformin dose is an independent determinant of [18 F]FDG accumulation in the wall and lumen of the large intestine in individuals treated with this drug.

Enhanced Release of Glucose Into the Intraluminal Space of the Intestine Associated With Metformin Treatment as Revealed by [18F]Fluorodeoxyglucose PET-MRI.

OBJECTIVE: Positron emission tomography (PET)-computed tomography has revealed that metformin promotes the intestinal accumulation of [18F]fluorodeoxyglucose (FDG), a nonmetabolizable glucose derivative. It has remained unknown, however, whether this accumulation occurs in the wall or intraluminal space of the intestine. We here addressed this question with the use of [18F]FDG PET-MRI, a recently developed imaging method with increased accuracy of registration and high soft-tissue contrast. RESEARCH DESIGN AND METHODS: Among 244 individuals with type 2 diabetes who underwent PET-MRI, we extracted 24 pairs of subjects matched for age, BMI, and HbA1c level who were receiving treatment with metformin (metformin group) or were not (control group). We evaluated accumulation of [18F]FDG in different portions of the intestine with both a visual scale and measurement of maximum standardized uptake value (SUVmax), and such accumulation within the intestinal wall or lumen was discriminated on the basis of SUVmax. RESULTS: SUVmax of the jejunum, ileum, and right or left hemicolon was greater in the metformin group than in the control group. [18F]FDG accumulation in the ileum and right or left hemicolon, as assessed with the visual scale, was also greater in the metformin group. SUVmax for the intraluminal space of the ileum and right or left hemicolon, but not that for the intestinal wall, was greater in the metformin group than in the control group. CONCLUSIONS: Metformin treatment was associated with increased accumulation of [18F]FDG in the intraluminal space of the intestine, suggesting that this drug promotes the transport of glucose from the circulation into stool.

Relation between HOMA-IR and insulin sensitivity index determined by hyperinsulinemic-euglycemic clamp analysis during treatment with a sodium-glucose cotransporter 2 inhibitor.

We had aimed to determine whether homeostasis model assessment-insulin resistance (HOMA-IR) reflects insulin resistance-sensitivity during treatment with a sodium-glucose cotransporter 2 inhibitor (SGLT2i). Hyperinsulinemic-euglycemic clamp analysis was performed in 22 patients with type 2 diabetic patients taking dapagliflozin (5 mg/day before or after breakfast). Propensity score matching of these individuals (SGLT2i group) for age, sex, body mass index, and clamp-derived tissue glucose uptake rate with 44 type 2 diabetic patients who had undergone clamp analysis without SGLT2i treatment (control group) identified 17 paired subjects in each group for further analysis of the relation between HOMA-IR and a clamp-derived insulin sensitivity index (ISI). Natural log-transformed HOMA-IR was negatively correlated with ISI in both SGLT2i (r = -0.527, p = 0.030) and control (r = -0.534, p = 0.027) groups. The simple regression lines for log-transformed HOMA-IR and ISI in the two groups showed similar slopes but differed in their intercepts. Multivariate analysis revealed that HOMA-IR for patients with the same ISI in the two groups was related by the formula: HOMA-IRcontrol = HOMA-IRSGLT2i × 2.45. In conclusion, HOMA-IR was well correlated with ISI during SGLT2i treatment, but values corresponding to the same ISI were lower in the SGLT2i group than in the control group.

Reliability and validity of the Japanese version of the Mental Health Self-management Questionnaire among people with mental illness living in the community.

BACKGROUND: Self-management is an important factor in maintaining and promoting mental health and recovery from mental health challenges. Thus, it is important to assess and support mental health self-management. In this study, we aimed to develop the Japanese version of the Mental Health Self-management Questionnaire (MHSQ-J), a scale to assess mental health self-management strategy, and clarify its psychometric properties among people with mental illness living in Japan. METHODS: An anonymous self-administered survey including MHSQ-J was conducted for psychiatric outpatient users (N = 295), and 104 of the participants completed MHSQ-J again about two weeks later. Internal consistency was assessed with Cronbach's α, and test-retest reliability was confirmed by the intraclass correlation coefficient (ICC). Construct validity was assessed based on structural validity with confirmatory factor analysis (CFA) and exploratory factor analysis (EFA), and hypotheses testing. The Self-management Skill Scale, the University of Tokyo Health Sociology version of the Sense of Coherence Scale ver1.2, the Japanese version of Self-identified Stage of Recovery Part-B, the Japanese version of the Flourishing Scale, and the Japanese version of the WHO Disability Assessment Scale 2.0 were used for hypotheses testing. RESULTS: Data from 243 respondents were analyzed. The result of CFA, the goodness-of-fit indices showed marginal fit (AGFI = .830, CFI = .852, RMSEA = .072). EFA identified three factors (Clinical, Empowerment, and Vitality), and the results suggested that the factor structure of the Japanese version of MHSQ was similar to the original 3-factor structure. Significant correlations were found with the hypotheses testing variables related to self-management and recovery, especially on the total score, the Empowerment subscale, and the Vitality subscale. Cronbach's α (Clinical: .65, Empowerment: .81, Vitality: .75, Total: .83) and ICC (Clinical: .75, 95% confidence interval (CI) [.62, .84], Empowerment: .81, 95% CI [.70, .88], Vitality: .62, 95% CI [.44, .75], Total: .84, 95% CI [.75, .90]) indicated good reliability. CONCLUSION: The results show that MHSQ-J has acceptable reliability and validity to measure the use of self-management strategies for mental health among community living people with mental illness in Japan.

Circulating platelet-neutrophil aggregates play a significant role in Kawasaki disease.

BACKGROUND: Circulating platelet-neutrophil aggregates play a crucial role in amplifying acute inflammation and could promote adverse effects involving vascular injury. The aim of this study was to evaluate the role of platelet-neutrophil aggregates in Kawasaki disease (KD). METHODS AND RESULTS: Forty patients with KD (30 intravenous immunoglobulin [IVIG] responders and 10 IVIG non-responders), 7 febrile patients with bacterial infections, and 9 normal volunteers were analyzed. Thirty-three patients with KD were treated with IVIG, and 7 were treated with IVIG plus prednisolone. We evaluated the rate of platelet-neutrophil aggregates and measured the platelet factor 4 (PF4) and ß-thromboglobulin (ß-TG) levels. The rate of platelet-neutrophil aggregates was significantly higher in patients with KD than those with bacterial infection and normal volunteers. The rate of platelet-neutrophil aggregates was significantly higher in patients with coronary artery abnormalities (CAA) than in those without CAA, and was correlated with PF4 and ß-TG levels in patients with KD. Comparing time-course analysis, the rate of platelet-neutrophil aggregates was significantly decreased in patients treated with IVIG plus prednisolone than in those treated with IVIG alone. CONCLUSIONS: The findings demonstrate that platelet-neutrophil aggregates are significantly present in higher rates and are closely related to pathological developments of CAA in KD. Additional prednisolone treatment for patients in the acute phase of KD could suppress platelet-neutrophil aggregates, indicating that platelet-neutrophil aggregates would inhibit amplified reciprocal vascular inflammatory activation.

Immunoglobulin G values before treatment are correlated with the responsiveness to initial intravenous immunoglobulin therapy for Kawasaki disease.

BACKGROUND: Low levels of serum immunoglobulin G (IgG) before intravenous immunoglobulin (IVIG) therapy for Kawasaki disease (KD) have been reported as one of the risk factors for coronary artery abnormalities (CAAs). This risk factor needs to be re-evaluated because the dosage of IVIG has changed from 0.2-0.4 g/kg/day for 5 days to a single high dose of 2 g/kg. METHODS: We reviewed the clinical records of KD patients admitted to our hospital from January 2001 to August 2011. Patients who were given a single high dose of IVIG within 7 days of illness, and who had blood collected for serum immunoglobulin values before treatment, were selected. The serum immunoglobulin levels and coronary artery diameters measured by echocardiogram were transformed to z-scores. RESULTS: The subjects were 197 KD patients, including 22 IVIG nonresponders and 16 patients with CAAs. Of these, 150 (76%) had a z-score for IgG (IgGz) of ≤0. There were no differences in IgGz values between patients with CAAs and those without CAAs. However, nonresponders had higher IgGz values than responders (median, 25th percentile and 75th percentile: -0.26, -0.83 and 0.34 vs. -0.79, -1.40 and -0.03; p = 0.020). Logistic regression analysis showed that the IgGz value was an independent risk factor for resistance to IVIG (OR 1.36, 95% CI 1.002-1.849; p = 0.048). CONCLUSIONS: Low IgGz values were not a risk factor for CAAs in this study. However, KD patients with relatively high IgGz values before treatment may have an increased risk of resistance to initial IVIG therapy. © 2014 S. Karger AG, Basel.

An elevated value on drug-induced lymphocyte stimulation test for immunoglobulin is an immunological abnormality of Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is an acute febrile vasculitis in childhood. Currently, treatment with 2 g/kg of intravenous immunoglobulin (IVIG) is recommended. Previously we had encountered a patient with KD who showed persistent fever and a severe eruption after IVIG treatment. Using a drug-induced lymphocyte stimulation test (DLST), he was positive for an immunoglobulin product. The aim of this study was to clarify the importance of a positive value for the DLST for immunoglobulin products in KD patients. METHODS: Subjects were 30 confirmed KD patients treated with IVIG at the Kagoshima Medical Association Hospital. DLST values were compared between patients with additional events and those without additional events using the stimulation index (SI = value of (3)H-thymidine absorption with antigen/without antigen). Additional events were defined as symptoms observed after IVIG that were considered unexplainable by the symptoms of KD alone. RESULTS: DLST results were evaluated in 13 patients with additional events and 17 patients without additional events. Elevated DLST values were observed not only in patients with additional events but also in those without additional events. Elevated SI values were observed in the initial 14 days after IVIG and the SI values in this period were significantly higher than those after day 14 (initial 14 days, n = 20, 194 +/- 112%; after day 14, n = 10, 117 +/- 66%, p = 0.010). CONCLUSIONS: Elevated SI values of DLST for immunoglobulin products are not related with additional events. Our results show they may represent one of the immunological abnormalities of KD.

Decrease in glomerular filtration rate by plasma low-density lipoprotein cholesterol in subjects with normal kidney function assessed by urinalysis and plasma creatinine.

OBJECTIVE: It has not been well defined whether plasma low-density lipoprotein cholesterol (LDL-C) progresses arteriolosclerosis (arteriosclerosis of small arteries) or not. Estimated glomerular filtration rate (e-GFR) is an indicator of the function of renal arterioles and capillaries of glomeruli. The relationship between e-GFR and plasma LDL-C was studied to estimate the effect of plasma LDL-C on the function of renal arterioles and capillaries of glomeruli to speculate the effect of plasma LDL-C on arteriolosclerosis. METHODS AND RESULTS: Major coronary risk factors; blood pressure, plasma lipids, and fasting plasma glucose were compared among 4 groups of examinees of a health evaluation and promotion center separated by e-GFR, namely, Control group, Group 1, 2, 3 from highest e-GFR to lowest e-GFR. Numbers of total male and female subjects were 4602 and 2920, respectively. Plasma LDL-C levels were significantly high in Group 2 and 3 in all male subjects and high in Group 1, 2, and 3 in male subjects with age of fifties, compared with Control group. Plasma LDL-C levels were significantly high in Group 1, 2, and 3 in all female subjects and high in Group 2 and 3 in female subjects with age of fifties, compared with Control group. Plasma levels of LDL-C were not significantly different at each years of age in subjects with age of fifties in both sex. BMI and waist circumference were higher in male subjects with low e-GFR but not in female subjects. Blood pressure and fasting plasma glucose were not high in subjects in Group 1, 2, and 3, compared with Control group in all subjects and subjects with age of fifties in both sex. CONCLUSIONS: We concluded that the high plasma level of LDL-C was the major risk factor among coronary risk factors to reduce GFR probably due to impairing the function of renal arterioles and capillaries of glomeruli in subjects with normal kidney function assessed by urinalysis and plasma creatinine.

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.

Platelet vascular endothelial growth factor is a useful predictor for prognosis in Kawasaki syndrome.

Kawasaki syndrome (KS) is an acute febrile vasculitis of childhood. Coronary artery abnormalities (CAA) are a significant problem in KS patients. High dose intravenous immunoglobulin (IVIG) is effective for reducing the occurrence of CAA. Clinical and histopathological findings suggest that vascular endothelial growth factor (VEGF) is involved in CAA. In circulating blood, newly activated platelets are the major source of VEGF, which is released in large amounts in vascular inflammation. The present study analysed 80 KS patients (69 IVIG responders and 11 IVIG non-responders) and evaluated the role of platelet VEGF in KS vasculitis. Serum VEGF and platelet VEGF levels were significantly higher in KS patients than controls (P < 0.001). Platelet VEGF reflected the reactivity of IVIG treatment and was decreased in responders (P < 0.001), but remained increased in non-responders (P = 0.01). Platelet VEGF levels, but not serum VEGF levels, before IVIG were significantly correlated with the maximum CAA z-score (r = 0.524, P = 0.02). Our findings demonstrate that platelet VEGF may reflect the severity of vasculitis related to the pathological development of CAA in KS. Platelet VEGF may be an important feature of KS pathophysiology.