Swee Chye Quek

Prevalence and severity of asthma, rhinitis, and eczema in Singapore schoolchildren.

This study was part of an international effort to evaluate the epidemiology of asthma and allergic diseases around the world. The aim was to assess the prevalence and severity of these disorders in Singapore schoolchildren. The international study of asthma and allergies in childhood (ISAAC) written questionnaire was administered to 6238 schoolchildren. The respondents were parents of a 6-7 year cohort (n = 2030), and schoolchildren aged 12-15 years (n = 4208). The overall cumulative and 12 month prevalence of wheezing were 22% and 12%, respectively. The prevalence of doctor diagnosed asthma was 20%. Rhinitis was reported by 44% and chronic rashes by 12%. Multiple logistic regression analysis showed that a higher prevalence of wheezing and rhinitis was associated with males, and subjects of higher socioeconomic status (based on type of housing and total family income). More severe asthma related symptoms were present in Malays and Indians than in the Chinese. Allergic disorders are common in Singapore and prevalence is comparable to some populations in the West. Demographic and socioeconomic factors appear to influence the prevalence and severity of these disorders.

Immunosuppressive therapy in acute myocarditis: an 18 year systematic review

Background: Immunosuppressive therapy is reportedly ineffective in adults with acute myocarditis. Aims: To systematically review the impact of immunosuppressive therapy on the outcome of acute myocarditis in children. Methods: A literature search for articles published from 1984 to 2003 was conducted with the following keywords: myocarditis, dilated cardiomyopathy, and immunosuppression. The relevant studies were systematically reviewed and comparison of treatment effect was made by calculating the odds ratio (OR) and confidence interval (CI) using the exact method based on the exact discrete reference distribution. Results: Of the 1470 articles found, only nine studies were eligible. The odds for improvement with immunosuppression was between 4.33 (95% CI 0.52 to 52.23) and 2.7 (95% CI 0.59 to 14.21). Addition of a second immunosuppressive agent to prednisolone only proved effective in one randomised controlled trial (OR 0.09, 95% CI 0.01 to 0.52). Heterogeneity of these studies precluded pooled odds ratio. Conclusion: Current data suggest that immunosuppressive therapy does not significantly improve outcomes in children with acute myocarditis and there is insufficient evidence for its routine use. However, statistical power to detect a significant difference in the treatment effect may be limited because of the small number of subjects. This, together with problems of diagnosis, varying treatment practices, and a relative lack of evidence based guidelines would support efforts for a large multicentre, randomised controlled trial to better define the role of immunosuppression in acute myocarditis.

Use of a reformulated Oka strain varicella vaccine (SmithKline Beecham Biologicals/Oka) in healthy children

The first live-attenuated Oka strain varicella vaccines needed to be stored at −20°C. Reformulation of this vaccine by SmithKline Beecham Biologicals has provided a vaccine shelf life of up to 2 years when stored at +2°C to +8°C. In this study the immunogenicity and reactogenicity of two different production lots of this reformulated vaccine at two different titres each, which corresponded to the release and expected expiry titres, were evaluated. A double-blind randomised clinical trial was conducted in healthy children aged from 9 to 24 months. Immunogenicity was assessed by the measurement of varicella specific antibodies in paired serum samples taken before and from 35 to 63 days post vaccination. Reactogenicity was assessed by the evaluation of any untoward reactions occurring up to 42 days post vaccination. In order to assess protective efficacy, parents of these subjects were contacted approximately 6 months after completion of the trial. One hundred and ninety-one subjects were recruited into the study. Of the 181 initially seronegative subjects who completed the trial according to the protocol, 179 showed seroconversion (98.9%). Reactions to the vaccine were minor and observed in 46/191 (24%) of subjects. Rashes were present in 19, fever in 22, and both fever and rashes in 5. Rashes were mainly maculo-papular in nature but were vesicular in 6. Febrile reactions were shortlived. After a 6-month follow up period, attenuated varicella with minor clinical symptoms was diagnosed in 6/52 vacinees who had close contact with natural varicella (attack rate=11.5%).

Outcome of surgical closure of doubly committed subarterial ventricular septal defect.

BACKGROUND From 1986 to March 1997, 128 patients diagnosed to have doubly committed subarterial ventricular septal defects (VSD) were reviewed. Patients with aortic regurgitation (AR), and aortic valve (AV) deformity or a large left-to-right shunt across the VSD were offered operation. Forty-five patients (27 men, 18 women) agreed to surgical closure of their VSDs. METHODS Thirty-eight patients had VSD closure alone, and 7 had an additional AV repair. Other associated defects corrected at operation were closure of atrial septal defects, closure of other ventricular septal defects, ligation of patent ductus arteriosus, and repair of ruptured sinus Valsalva aneurysm. RESULTS There was no mortality nor major morbidity associated with operation. In the 26 patients with AR and AV deformity preoperatively, valve repair was performed in 6 patients. The condition of AR improved in 4, and remained unchanged in 22 patients. In the 10 patients with a deformity of the AV and no AR preoperatively, the condition remained unchanged in 5 patients, from whom 1 had valve operation, but progressed in 5 patients postoperatively at a mean follow-up of 6.4 years. In 9 patients with no deformity of the AV and no AR preoperatively, there was no postoperative AR and no progress of valve deformity. CONCLUSIONS Excellent results were obtained with VSD closure and AV repair. Surgical closure of VSD, if performed before the onset of AV deformity, may prevent progressive AR. If AV repair is performed after the onset of AV deformity, progressive AR may not always be prevented.

Abdominal Coarctation and Alagille Syndrome

Structural cardiac defects such as peripheral pulmonary stenosis are well-described in Alagille syndrome (AS), which is transmitted in an autosomal dominant inheritance. The genetic defect, with incomplete penetrance and variable expression, is localized to the short arm of chromosome 20. Abdominal coarctation is an uncommon congenital anomaly, with a spectrum of symptoms that may range from hypertension, intermittent claudication to abdominal pain. The association of abdominal coarctation with AS is rarely described. We report such a patient who also had aberrations of the visceral vascular supply involving the celiac, splenic, and superior mesenteric arteries. The indications to treat the coarctation, and in the context of a patient with AS, in whom liver transplantation may be contemplated at some stage, merit discussion.

Influence of surgery on aortic valve prolapse and aortic regurgitation in doubly committed subarterial ventricular septal defect

Doubly committed subarterial ventricular septal defects should be closed surgically once aortic valve deformity is present before the onset of aortic regurgitation.

The effect of Kawasaki disease on childhood allergies – a sibling control study

To cite this article: Liew WK, Lim CWT, Tan TH, Wong KY, Tai BC, Quek SC, Bever HV. The effect of Kawasaki disease on childhood allergies – a sibling control study. Pediatr Allergy Immunol 2011; 22: 488–493.

A systematic review on the efficacy and safety of transcatheter device closure of ventricular septal defects (VSD).

BACKGROUND Advances in interventional techniques now allow for transcatheter treatment of some ventricular septal defects (VSD), although there remain concerns about adverse events. We performed a systematic review to look at outcomes and complications associated with transcatheter closure of VSD. METHOD A PubMed search for series in English on device closure of VSD from 2003 to June 2012 was performed. We excluded small series that were included in multicenter studies and patients who had acquired VSD following myocardial infarction. The random effects model was used to obtain pooled estimates of success and complications. RESULTS A total of 37 publications comprising 4,406 patients with VSD (perimembranous = 3,758, muscular = 419, intracristal = 47, doubly committed subarterial = 36, multiple = 16, postsurgical = 123, unclassified = 7) were included in this analysis. The age of patients ranged from 3 days to 84 years. The pooled estimate of successful device implantation was 96.6% (95% CI: 95.7-97.5). The most common complication is residual shunt (pooled estimated 25.5%; 95% CI: 18.9-32.1). Others included valvular defects (pooled estimate 4.9%; 95% CI: 3.4-6.4) and arrhythmias (pooled estimate 10.6%; 95% CI: 8.4-12.7). DISCUSSION AND CONCLUSION Our analysis suggests that transcatheter device closure of VSD is safe and yields good results. The limitations of this study are difficulties in analyzing different devices individually, and segregating the different VSD types. Further stratification by type of VSD, age of patients, and prevention of complications is needed before this can be recommended for routine treatment.

Transcatheter embolization of coronary artery fistula with controlled release coils

ABSTRACT The treatment for large congenital coronary cameral fistulas has been surgical but with advances in interventional catheterization techniques transcatheter embolization of these fistulas with coils or detachable balloons is now possible. This report describes occlusion of a congenital coronary arteriovenous fistula in a 6‐year‐old girl.

The Effects of Three Factor VII Polymorphisms on Factor VII Coagulant Levels in Healthy Singaporean Chinese, Malay and Indian Newborns

Factor VII (FVII) is an independent risk factor for coronary artery disease. Three polymorphisms of the factor VII gene (F7) were studied in a group of healthy newborns comprising 561 Chinese, 398 Malays and 226 Asian Indians from Singapore. The allele frequencies of 3 polymorphisms (R353Q, Promoter 0/10bp Del/Ins and Intron 7) in the FVII gene were ascertained through genotyping by polymerase chain reaction and restriction digestion of amplified fragments. In Chinese the minor allele frequencies are Q: 0.04, Ins: 0.03, R7: 0.44; Malays, Q: 0.06, Ins: 0.10, R7: 0.41; and Indians, Q: 0.25, Ins: 0.23, R7: 0.43. Strong linkage disequilibrium (Δ > 0.7) is observed between the 0/10bp and the R353Q sites in all ethnic groups. We conclude that: (i) the prevalence of the minor Q and Ins alleles of the R353Q and 0/10 bp polymorphisms are significantly higher in the Indian newborns than the Chinese and Malays; (ii) the Q allele is significantly associated (p = 0.01) with a lower plasma FVII coagulant level in the Indian and Malay neonates; and this polymorphism explains up to 3.8% of the variance in FVII coagulant levels; (iii) there is no significant difference in allele frequencies of the three polymorphisms between neonates with and without family histories of CAD.