Chi-Di Liang

Two new susceptibility loci for Kawasaki disease identified through genome-wide association analysis

To find new candidate loci predisposing individuals to Kawasaki disease, an acute vasculitis that affects children, we conducted a genome-wide association study in 622 individuals with Kawasaki disease (cases) and 1,107 controls in a Han Chinese population residing in Taiwan, with replication in an independent Han Chinese sample of 261 cases and 550 controls. We report two new loci, one at BLK (encoding B-lymphoid tyrosine kinase) and one at CD40, that are associated with Kawasaki disease at genome-wide significance (P < 5 × 10−8). Our findings may lead to a better understanding of the role of immune activation and inflammation in Kawasaki disease pathogenesis.

The relationship of eosinophilia to intravenous immunoglobulin treatment failure in Kawasaki disease

To investigate the role of eosinophils in Kawasaki disease (KD) and the relationship to initial intravenous immunoglobulin (IVIG) treatment failure. A retrospective analysis of all children who were admitted and met the criteria of KD between 1999 and 2005. The patients were divided into IVIG‐responsive and IVIG‐resistant groups. A total of 185 patients were enrolled during the study period. A series of blood eosinophils and biochemistry studies were correlated to the effectiveness of IVIG. The neutrophils percentage before IVIG treatment (pre‐IVIG), leukocyte counts within 3 days after IVIG treatment (post‐IVIG), liver enzyme, albumin levels, and post‐IVIG eosinophils percentage were all significantly different between the two groups in univariate analysis. Under multivariate analysis with logistic regression, post‐IVIG eosinophilia [peripheral blood (PB) eosinophils ≥4%] had an inverse correlation to KD patients with IVIG‐resistance (p = 0.003). Also, pre‐IVIG hypoalbuminemia (albumin ≤3.0 g/dl) was positively correlated to IVIG‐resistance (p = 0.018). Further analysis showed that the PB eosinophils was markedly increased in the acute stage and returned to normal 3 weeks after IVIG treatment (p < 0.001). Eosinophil levels are highly elevated in the acute stage of KD both before and after the IVIG treatment. Post‐IVIG treatment eosinophilia has an inverse correlation to KD patients with IVIG‐resistance and may indicate IVIG‐responsive. This may be a valuable factor to survey for the necessity of a second dose IVIG treatment.

Serum albumin level predicts initial intravenous immunoglobulin treatment failure in Kawasaki disease

Objectives:  Kawasaki disease (KD) is a systemic vasculitis primarily affecting children who are <5 years old. Intravenous immunoglobulin (IVIG) is the standard therapy for KD. However, many patients with KD still show poor response to initial IVIG treatment. This study was conducted to investigate the risk factors for initial IVIG treatment failure in KD.

ITPKC single nucleotide polymorphism associated with the Kawasaki disease in a Taiwanese population.

Kawasaki disease (KD) is characterized by systemic vasculitis with unknown etiology. Previous studies from Japan indicated that a gene polymorphism of ITPKC (rs28493229) is responsible for susceptibility to KD. We collected DNA samples from 1,531 Taiwanese subjects (341 KD patients and 1,190 controls) for genotyping ITPKC. In this study, no significant association was noted for the ITPKC polymorphism (rs28493229) between the controls and KD patients, although the CC genotype was overrepresented. We further combined our data with previously published case/control KD studies in the Taiwanese population and performed a meta-analysis. A significant association between rs28493229 and KD was found (Odds Ratio:1.36, 95% Confidence Interval 1.12–1.66). Importantly, a significant association was obtained between rs28493229 and KD patients with aneurysm formation (P = 0.001, under the recessive model). Taken together, our results indicated that C-allele of ITPKC SNP rs28493229 is associated with the susceptibility and aneurysm formation in KD patients in a Taiwanese population.

CASP3 gene single-nucleotide polymorphism (rs72689236) and Kawasaki disease in Taiwanese children

Kawasaki disease (KD) is characterized by systemic vasculitis of unknown etiology. A study from Japan reported that G to A substitution of a single-nucleotide polymorphism (SNP) located in the 5′-untranslated region of caspase 3 (CASP3) (rs72689236), which was associated with nuclear factor of activated T cell-mediated T-cell activation, is responsible for susceptibility to KD. This study was conducted to investigate whether the polymorphism of CASP3 is responsible for susceptibility and coronary artery lesion (CAL) formation in KD in the Taiwanese population. A total of 1092 subjects (341 KD patients and 751 controls) were investigated to identify an SNP of rs72689236 using Invader assays (Third Wave Technologies). Our data provided a borderline significant association between the genotypes and allele frequency of rs72689236 in control subjects and KD patients (P=0.0535 under the dominant model; P=0.0575 under the allelic model). The A allele of rs72689236 in KD patients and in patients with CAL and intravenous immunoglobulin resistance was seen in a higher frequency. Importantly, a significant association was obtained between rs72689236 and KD patients with aneurysm formation (P=0.009, under the recessive model). The A allele of rs72689236 is very likely to be a risk allele in the development of aneurysm in patients with KD.

Small Bowel Intussusception in Symptomatic Pediatric Patients: Experiences with 19 Surgically Proven Cases

Nineteen cases of surgically proven symptomatic pediatric small bowel intussusceptions (SBI) were retrospectively reviewed. Clinical presentations included vomiting (89.5%), abdominal pain and/or irritable crying (89.5%), fever (52.6%), bloody stools (26.3%), palpable abdominal masses (15.8%), hematemesis (10.5%), jaundice (5.3%), and seizures (5.3%). The duration between symptom onset and hospitalization ranged between 20 and 336 hours (average 75.8 hours). Two patients with suspected appendicitis and small bowel obstruction were operated on promptly. Sonograms revealed target lesions (average diameter 2.9 cm) suggestive of intussusception in 13 out of 17 patients, with 10 lesions located in the paraumbilical or left abdominal regions. Barium enemas in 12 of these 13 patients demonstrated no colonic lesions. Diagnosis and surgery were delayed in 16 patients (average delay = 32 hours). The remaining 1 patient with positive sonographic findings underwent early surgery after computed tomographic (CT) confirmation of SBI. Surgery revealed ileoileal intussusceptions in 11 patients, jejunojejunal in 4, jejunoileal in 3, and duodenojejunal in 1. Eight patients had lead points. Bowel complications (ischemia, necrosis, or perforation) occurred in 8 patients. The duration between symptom onset and surgery in patients with bowel complications was significantly longer than for patients without complications (p = 0.0026). In conclusion, delayed diagnosis and surgical treatment in symptomatic pediatric patients with SBI were common, leading to a high rate (42%) of bowel complications. Sonographic demonstration of a 2–3 cm target lesion, especially if paraumbilical or left abdominal, is suggestive of SBI and may obviate the need for a barium enema; however, CT is helpful for confirming SBI. In symptomatic SBI, once diagnosed, early surgical referral is strongly recommended.

Coronary artery fistula associated with Kawasaki disease.

BACKGROUND The aim of this study was to investigate the rate, risks factors, and clinical impact of coronary artery fistula (CAF) in Kawasaki disease (KD). METHODS From February 1999 to December 2007, a total of 325 pediatric patients fulfilled the diagnostic criteria of KD and admitted for intravenous immunoglobulin treatment were enrolled in this study. Patients with and without CAF were designated as group 1 and group 2, respectively. Patients of group 1 were further subdivided as with and without coronary artery lesions (CALs). The clinical presentations, laboratory data, and outcomes were compared among the groups. RESULTS The mean age of the 325 patients was 21.1 months. Group 1 had 17 patients, and group 2 had 308 patients. The rate of CAF in KD was 5.3%. There were significant differences between group 1 and group 2 patients regarding age (11.8 +/- 1.8 vs 21.5 +/- 1.2 months, P = .01), the presence of CAL (64.7% vs 25%, P < .01), white blood cell counts (16.4 +/- 1.3 vs 13.5 +/- 0.3 x 10(3)/mm(3), P = .01), and platelet counts (432.1 +/- 39.1 vs 346.4 +/- 8.4 x 10(3)/mm(3), P = .02). Spontaneous closure of CAF was observed in 7 (41%) of the 17 patients during follow-up (mean 45 months). Group 1 patients without CAL had a more benign clinical course (total fever day 5.8 +/- 0.6 vs 8.6 +/- 0.8, P = .03) and higher spontaneous closure rate (5/6 vs 2/11, P = .035) than patients with CAL. CONCLUSIONS Patients of young age, CAL, high white blood cell counts, and high platelet counts have higher rate of CAF formation. Approximately 5% KD patients may associate with CAF, but most of them have good clinical outcome during follow-up.

Amplatzer Septal Occluder Closure of Atrial Septal Defect: Evaluation of Transthoracic Echocardiography, Cardiac CT, and Transesophageal Echocardiography

OBJECTIVE The purpose of this study was to compare transthoracic echocardiography (TTE), cardiac CT, and transesophageal echocardiography (TEE) in the evaluation of secundum atrial septal defect (ASD) for closure with an Amplatzer septal occluder in pediatric patients. SUBJECTS AND METHODS The cases of 28 children with ASD initially diagnosed with TTE who were scheduled for cardiac CT for evaluation for insertion of an Amplatzer septal occluder under TEE guidance were reviewed. The patients were divided into a group with small ASD (long axis < 1.5 cm) and a group with large ASD (long axis > or = 1.5 cm). Measurements of the ASD obtained at TTE, cardiac CT, and TEE were compared. Kappa statistics were used to correlate the diagnostic value of cardiac CT assessed by two independent reviewers. RESULTS After cardiac CT, six patients were excluded from occluder implantation; therefore, 22 patients (seven boys, 15 girls; mean age, 4.95 years; range, 2-11 years) were included in the study. There were no significant differences in the ages and sexes of the patients in the two groups, but pulmonary-to-systemic blood flow ratio in the large-ASD group was significantly greater than that in the small-ASD group (3.54 +/- 1.43 vs 1.89 +/- 0.36; p = 0.001). With respect to long- and short-axis lengths of the ASD, interatrial septum, and four rims and to detection of rim deficiency, neither group had a significant difference between cardiac CT findings at ventricular end-systole and TEE findings. The long axis of the ASD in the large-ASD group measured at cardiac CT at end-systole and TEE was significantly longer than the long axis measured at TTE (p = 0.012). A high diagnostic score with good interobserver correlation (kappa = 0.674-0.750) validated the feasibility of cardiac CT in the assessment of ASD for closure with an Amplatzer septal occluder. CONCLUSION The long axis of a large ASD can be underestimated at TTE. Cardiac CT seems comparable with TEE in the assessment of ASD and is helpful in noninvasive evaluation for Amplatzer septal occluder implantation, especially for large ASD.

Myocarditis Complicated by Complete Atrioventricular Block: Nine Years' Experience in a Medical Center

BACKGROUND Myocarditis complicated with complete atrioventricular block (CAVB) is rare in children. The purpose of this study was to report the outcome of myocarditis with CAVB in our institution. METHODS Between June 1998 and June 2007, nine pediatric patients (aged from 1.5 to 16 years) were admitted, presenting with acute myocarditis with CAVB. We analyzed their clinical presentations, biochemistry and serology studies, chest X-rays, electrocardiograms, echocardiography, complications and outcomes. RESULTS Hypotension and Stokes-Adams seizures occurred in five and four of our patients, respectively. Cardiomegaly of chest X-ray was common in eight (89%) of our patients. Echocardiography revealed impaired left ventricular performance in three patients. Six patients suffered ventricular tachycardia (VT). Three cases of VT occurred before pacemaker implantation and the others occurred afterwards. Eight patients survived. Six of them regained sinus rhythm within 12 days (range 1-12 days), and two had a right bundle branch block at follow-up. Two patients had persistent CAVB, and one received permanent pacemaker implantation; the other received supportive care. One patient died due to persistent low cardiac output and a new onset of VT on the 4th admission day. During a follow-up period of 56+/-27 months, all eight surviving patients remained asymptomatic. CONCLUSIONS The outcome of CAVB complicated with myocarditis is variable. Most of our patients resumed normal heart function. The incidence of persistent CAVB was 22%. VT is a common and serious complication, but it can be effectively treated medically. Persistent low cardiac output after pacemaker implantation and late onset VT should be considered as risk factors of mortality.

Glyceraldehyde-3-phosphate dehydrogenase is a reliable internal control in Western blot analysis of leukocyte subpopulations from children.

To study differences in the development of immunity, leukocytes from cord blood are often compared with those from adult peripheral blood. Western blot analysis is a common method for detecting proteins. In this study, we investigated the reliability of using different housekeeping proteins (β-actin, β-tubulin, and glyceraldehyde-3-phosphate dehydrogenase [GAPDH]) as internal controls for different leukocyte subpopulations from infants, children, and adults. Our results showed that the expression levels of β-actin and β-tubulin were much lower in cord blood leukocytes than in adult leukocytes, and this expression pattern persisted in children up to 3 years old. Further study revealed that the β-actin expression level in newborns was especially lower in CD14-positive monocytes. However, cord blood and adult peripheral blood monocytes had similar expression levels of β-actin messenger RNA (mRNA). Further experiments showed that posttranslational regulation was responsible for the low β-actin expression level in neonatal monocytes. Thus, researchers should carefully assess the appropriate use of housekeeping gene-encoded proteins as internal standards to normalize samples for comparisons of different leukocyte populations from subjects of different ages. In this study, we determined that GAPDH was a more reliable internal control than others in Western blot analysis for comparing the development of immunity among infants, children, and adults.