P K H Tam

Queen Mary Hospital, Hong Kong, Hong Kong

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Publications (53)141.99 Total impact

  • Article: Laparoscopic inguinal hernia repair in premature neonates: is it safe?
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    ABSTRACT: OBJECTIVE: With advances in clinical medicine, many premature babies nowadays can have excellent survival outcomes. As the incidence of inguinal hernias in this group is high and there is scarce data in the literature regarding the optimal timing for repair, this study aims to review our experience in laparoscopic repair in premature infants. METHODS: In our centre, premature neonates with inguinal hernia noted during hospitalization were offered laparoscopic repair when the body weights reached 2.5 kg unless there is contraindication for laparoscopy. A retrospective review was carried out for all premature neonates who underwent laparoscopic inguinal hernia repair from 2001 to 2011. The operative results, complications, incarceration risk and postoperative apnea risk were recorded. RESULT: A total of 79 premature neonates received laparoscopic inguinal hernia repair during this period. The mean gestational age at birth was 31.9 weeks (27-36 weeks) and the mean gestational age at operation was 46.5 weeks (33-92 weeks). One patient had incarceration and required emergency operation while waiting for the elective repair. The mean operative time was 44.9 min (25-93 min). One patient (1.3 %) had recurrence. No postoperative apnea was noted in any patient. CONCLUSION: Laparoscopic hernia repair is safe and feasible in premature neonates when they attain reasonable body size, as long as there is excellent anaesthesia support. Low risk of incarceration was noted in this study and it is worth waiting for the body weight to build up and hence facilitate laparoscopic repair.
    Pediatric Surgery International 01/2013; · 1.25 Impact Factor
  • Article: Thoracoscopic resection of congenital cystic lung lesions is associated with better post-operative outcomes.
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    ABSTRACT: INTRODUCTION: The incidence of congenital cystic lung lesions has been increasing in recent years due to better antenatal detection. With the introduction and maturation of thoracoscopy, the operative management for these lesions has seen advancement in the last decade. In this study, we aimed to compare the post-operative outcomes of patients who had thoracoscopic resection with those who underwent open resection. METHODS: A retrospective review of all patients who underwent surgery for congenital cystic lung lesions between January 1996 and June 2012 in a tertiary referral center was conducted. Patients' demographics, operative procedures and post-operative outcomes were analyzed. RESULTS: Sixty-seven patients were identified over the past 15 years. Thirty-nine patients had thoracoscopic resections and 28 had open resections. Thirteen patients in the thoracoscopic group required conversion. Both groups had similar demographics in terms of age, body weight and laterality of lesions. The mean operative time and blood loss in the two groups were comparable. Patients in the thoracoscopic group had significantly shorter duration of chest tube drainage (4.3 vs. 6.9 days, p = 0.004), shorter intensive care unit stay (2.5 vs. 5.9 days, p = 0.003) and shorter hospital stay (6.9 vs. 12.0 days, p < 0.001). Post-operative complication rate was similar between the two groups. Patients with body weight less than 5 kg showed a significantly higher conversion to open surgery as compared to those with body weight more than 5 kg (62.5 vs. 25.8 %, p = 0.049). CONCLUSION: Successful thoracoscopic resection for congenital cystic lung lesions results in better post-operative outcomes. However, this technique remains technically challenging in patients with body weight less than 5 kg.
    Pediatric Surgery International 01/2013; · 1.25 Impact Factor
  • Article: Thoracoscopic repair of oesophageal atresia: Experience of 33 patients from two tertiary referral centres.
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    ABSTRACT: BACKGROUND: With advances in minimally invasive surgery, thoracoscopic repair of oesophageal atresia has become popular in many centres worldwide and indeed has been described as the pinnacle of neonatal surgery. Here, we report our experience in two tertiary referral centres. METHODS: Thoracoscopic technique was introduced in 2007. Thus, a retrospective review of all patients diagnosed with oesophageal atresia was carried out. Patients who had thoracoscopic repair were included, and those who had open repair due to co-morbidities were excluded. Patient demographics, operative data, complications, and associated anomalies were noted. RESULTS: A total of thirty-three patients underwent thoracoscopic repair during the time period. Thirty-one were successfully repaired thoracoscopically. Two patients had conversions due to intra-operative instability. The mean body weight of the neonates was 2.58kg. The mean operative time was 146min. Three patients suffered from minor anastomotic leaks, which healed on conservative management. Seven patients had anastomotic strictures, which responded successfully to endoscopic dilatation. Two patients died in the post-operative period due to pneumonia. One patient had a recurrent fistula 3months after the primary repair, and he subsequently underwent a successful second repair. CONCLUSIONS: In experienced hands, thoracoscopic repair of oesophageal atresia is at least as good as open surgery but with less surgical trauma. Standard of post-operative care contributes significantly to post-operative outcome. Thoracoscopic technique is now our preferred approach.
    Journal of Pediatric Surgery 12/2012; 47(12):2224-2227. · 1.45 Impact Factor
  • Article: Fine mapping of the 9q31 Hirschsprung’s disease locus
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    ABSTRACT: Hirschsprung’s disease (HSCR) is a congenital disorder characterised by the absence of ganglia along variable lengths of the intestine. The RET gene is the major HSCR gene. Reduced penetrance of RET mutations and phenotypic variability suggest the involvement of additional modifying genes in the disease. A RET-dependent modifier locus was mapped to 9q31 in families bearing no coding sequence (CDS) RET mutations. Yet, the 9q31 causative locus is to be identified. To fine-map the 9q31 region, we genotyped 301 tag-SNPs spanning 7Mb on 137 HSCR Dutch trios. This revealed two HSCR-associated regions that were further investigated in 173 Chinese HSCR patients and 436 controls using the genotype data obtained from a genome-wide association study recently conducted. Within one of the two identified regions SVEP1 SNPs were found associated with Dutch HSCR patients in the absence of RET mutations. This ratifies the reported linkage to the 9q31 region in HSCR families with no RET CDS mutations. However, this finding could not be replicated. In Chinese, HSCR was found associated with IKBKAP. In contrast, this association was stronger in patients carrying RET CDS mutations with p=5.10×10−6 [OR=3.32 (1.99, 5.59)] after replication. The HSCR-association found for IKBKAP in Chinese suggests population specificity and implies that RET mutation carriers may have an additional risk. Our finding is supported by the role of IKBKAP in the development of the nervous system.
    Human Genetics 04/2012; 127(6):675-683. · 5.07 Impact Factor
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    Article: Association of CD247 with systemic lupus erythematosus in Asian populations.
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    ABSTRACT: Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with complex genetic inheritance. CD247 (CD3Z, TCRZ) plays a vital role in antigen recognition and signal transduction in antigen-specific immune responses, and is known to be involved in SLE pathogenesis. Weak disease association was reported for genetic variants in this gene in Caucasian studies for SLE, Crohn's disease and systemic sclerosis, but its role as a genetic risk factor was never firmly established. In this study, using a collection of 612 SLE patients and 2193 controls of Chinese ethnicity living in Hong Kong in a genome-wide study, single nucleotide polymorphisms (SNPs) in and around CD247 were identified as being associated with SLE. The two most significant SNPs in this locus were selected for further replication using TaqMan genotyping assay in 3339 Asian patients from Hong Kong, Mainland China, and Thailand, as well as 4737 ethnically and geographically matched controls. The association of CD247 with SLE in Asian populations was confirmed (rs704853: odds ratio [OR] = 0. 81, p = 2.47 × 10(-7); rs858543: OR = 1.10, p = 0.0048). Patient-only analysis suggested that rs704853 is also linked to oral ulcers, hematologic disorders and anti-double-stranded DNA (dsDNA) antibody production. A significant association between variants in CD247 and SLE was demonstrated in Asian populations. Understanding the involvement of CD247 in SLE may shed new light on disease mechanisms and development of new treatment paradigms.
    Lupus 01/2012; 21(1):75-83. · 2.34 Impact Factor
  • Article: The potency of allospecific Tregs cells appears to correlate with T cell receptor functional avidity.
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    ABSTRACT: CD4(+) CD25(+) regulatory T cells (T(reg) cells) are an attractive adoptive cell therapy in mediating transplantation tolerance. T-cell receptor (TcR) activation is critical for T(reg) function, suggesting that the TcR avidity of T(reg) cells used in therapy may affect the therapeutic outcome. To address this, we compared the regulatory capacity of T(reg) lines expressing TcRs derived from two TcR transgenic mice shown to have the same specificity but different functional avidities. T(reg) lines generated from CD4(+)CD25(+) T cells from C57BL/6 mice were transduced with one of either of these TcRs. The antigen specificity of the transduced T(reg) lines was confirmed in vitro. T(reg) lines expressing the TcR with higher functional avidity showed stronger suppressive capacity in a linked suppression model in vitro. Furthermore, the same T(reg) lines demonstrated a stronger proliferation in vivo following antigen exposure. Pretreatment of recipient BL/6 mice with these T(reg) cells, together with anti-CD8 antibody and Rapamycin therapies, prolonged survival of BALB/c skins, as compared with mice that received T(reg) lines with lower TcR avidity. Taken together, these data suggest that the TcR functional avidity may be important for T(reg) function. It highlights the fact that strategies to select T(reg) with higher functional avidity might be beneficial for immunotherapy in transplantation.
    American Journal of Transplantation 08/2011; 11(8):1610-20. · 6.39 Impact Factor
  • Article: Two missense variants in UHRF1BP1 are independently associated with systemic lupus erythematosus in Hong Kong Chinese.
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    ABSTRACT: UHRF1BP1 encodes a highly conserved protein with unknown function. Previously, a coding variant in this gene was found to be associated with systemic lupus erythematosus (SLE) in populations of European ancestry (rs11755393, R454Q, P=2.22 x 10⁻⁸, odds ratio=1.17). In this study, by a combination of genome-wide study and replication involving a total of 1230 patients and 3144 controls, we confirmed the association of this coding variant to SLE in Hong Kong Chinese. We also identified another coding variant in this gene that independently contributes to SLE susceptibility (rs13205210, M1098T, P=4.44 x 10⁻⁹, odds ratio=1.49). Cross-population confirmation establishes the involvement of this locus in SLE and indicates that distinct alleles are contributing to disease susceptibility.
    Genes and immunity 02/2011; 12(3):231-4. · 4.22 Impact Factor
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    Article: Performing Kasai portoenterostomy beyond 60 days of life is not necessarily associated with a worse outcome.
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    ABSTRACT: The introduction of Kasai portoenterostomy has dramatically improved the management and survival of children with biliary atresia. The success rate of this operation worldwide varies with different centers. In this respect, many authors have studied the correlation of a successful outcome with various factors, such as the experience and workload of the surgical center, the use of postoperative steroids, the underlying biliary anatomy, as well as the age of patients at the time of the operation. Indeed, the age of 60 days has been used by clinicians as a critical time beyond which the rate of success of the Kasai operation markedly reduces. Despite this worldwide adoption, clear evidence supporting this critical operative time is still lacking. We undertook a review of our experience in the management of children with biliary atresia and focused specifically on the issue of the timing of operation. We showed that performing the Kasai operation beyond the age of 60 days was not associated with a worse outcome and that a high percentage of patients could still achieve good bile flow with normal bilirubin postoperatively. Thus, we believe that until the age of 100 days, the age of the patients does not play a significant role in determining the success of the Kasai operation.
    Journal of pediatric gastroenterology and nutrition 11/2010; 51(5):631-4. · 2.18 Impact Factor
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    Article: Fine mapping of the 9q31 Hirschsprung's disease locus.
    [show abstract] [hide abstract]
    ABSTRACT: Hirschsprung's disease (HSCR) is a congenital disorder characterised by the absence of ganglia along variable lengths of the intestine. The RET gene is the major HSCR gene. Reduced penetrance of RET mutations and phenotypic variability suggest the involvement of additional modifying genes in the disease. A RET-dependent modifier locus was mapped to 9q31 in families bearing no coding sequence (CDS) RET mutations. Yet, the 9q31 causative locus is to be identified. To fine-map the 9q31 region, we genotyped 301 tag-SNPs spanning 7 Mb on 137 HSCR Dutch trios. This revealed two HSCR-associated regions that were further investigated in 173 Chinese HSCR patients and 436 controls using the genotype data obtained from a genome-wide association study recently conducted. Within one of the two identified regions SVEP1 SNPs were found associated with Dutch HSCR patients in the absence of RET mutations. This ratifies the reported linkage to the 9q31 region in HSCR families with no RET CDS mutations. However, this finding could not be replicated. In Chinese, HSCR was found associated with IKBKAP. In contrast, this association was stronger in patients carrying RET CDS mutations with p = 5.10 x 10(-6) [OR = 3.32 (1.99, 5.59)] after replication. The HSCR-association found for IKBKAP in Chinese suggests population specificity and implies that RET mutation carriers may have an additional risk. Our finding is supported by the role of IKBKAP in the development of the nervous system.
    Human Genetics 04/2010; 127(6):675-83. · 5.07 Impact Factor
  • Article: Clinical experience in managing pediatric patients with ultra-short bowel syndrome using omega-3 fatty acid.
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    ABSTRACT: Total parenteral nutrition (TPN) remains an important component of the management of short bowl syndrome in pediatric patients. However, prolonged TPN is known to be associated with cholestasis. Recently, the use of omega-3-fatty acid (Omegaven) has been proposed to improve TPN cholestasis. We present the early outcome after administration of Omegaven in four patients with ultra-short bowel syndrome. Based on our experience, it appears that omega-3 fatty acid can reverse and prevent the advent of TPN-related cholestasis, thereby significantly improving the process of intestinal adaptation. We suggest that clinicians consider this treatment option before proceeding to invasive surgery to reverse cholestasis. Prospective randomized trials are necessary to define a standard protocol and elucidate other potential benefits of this novel agent.
    European Journal of Pediatric Surgery 02/2010; 20(2):139-42. · 0.81 Impact Factor
  • Article: Management of choledochal cyst: 30 years of experience and results in a single center.
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    ABSTRACT: Choledochal cyst is usually diagnosed in childhood. Early treatment can prevent further complication. We report on our series of patients over the past 30 years. A retrospective study was performed on all pediatric patients who presented with choledochal cyst from January 1978 to December 2008. The main outcome measures recorded were the clinical presentation, management, and long-term outcome of the patients. Eighty-three patients presented to us during the caption period with a mean age at diagnosis of 45 months (0 month to 16 years). Diagnoses were made antenatally in 15 patients. The most common symptoms were abdominal pain (n = 39) and jaundice (n = 35). Seventy-five patients had surgery, in which 72 patients had resection of the cyst and Roux-en-Y hepaticojejunostomy. Ten were performed by laparoscopic means. We categorized the cysts based on the Todani classification. There was no mortality. No malignant change was documented. For those 4 who had Caroli disease, 2 underwent liver transplantation and 2 had hepatectomy. Overall early complication rate was 5.3% (4/75). Complete excision of cyst with Roux-en-Y hepaticojejunostomy is the treatment of choice, and the late result is good. Laparoscopic surgery is feasible. Long-term follow-up is necessary. There is no evidence to suggest that some type IV cysts are the result of disease progression from type I cysts.
    Journal of Pediatric Surgery 12/2009; 44(12):2307-11. · 1.45 Impact Factor
  • Article: Hirschsprung disease, associated syndromes and genetics: a review.
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    ABSTRACT: Hirschsprung disease (HSCR, aganglionic megacolon) represents the main genetic cause of functional intestinal obstruction with an incidence of 1/5000 live births. This developmental disorder is a neurocristopathy and is characterised by the absence of the enteric ganglia along a variable length of the intestine. In the last decades, the development of surgical approaches has importantly decreased mortality and morbidity which allowed the emergence of familial cases. Isolated HSCR appears to be a non-Mendelian malformation with low, sex-dependent penetrance, and variable expression according to the length of the aganglionic segment. While all Mendelian modes of inheritance have been described in syndromic HSCR, isolated HSCR stands as a model for genetic disorders with complex patterns of inheritance. The tyrosine kinase receptor RET is the major gene with both rare coding sequence mutations and/or a frequent variant located in an enhancer element predisposing to the disease. Hitherto, 10 genes and five loci have been found to be involved in HSCR development.
    Journal of Medical Genetics 02/2008; 45(1):1-14. · 6.36 Impact Factor
  • Article: Correlation between genetic variations in Hox clusters and Hirschsprung's disease.
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    ABSTRACT: Interactions between migrating neural crest cells and the environment of the gut are crucial for the development of the enteric nervous system (ENS). A key signalling mediator is the RET-receptor-tyrosine-kinase which, when defective, causes Hirschprung's disease (HSCR, colon aganglionosis). RET mutations alone cannot account for the variable HSCR phenotype, invoking interactions with as yet unknown, and probably inter-related, loci involved in ENS development. Homeobox (HOX) genes have a major role in gut development as depicted by the enteric Hox code. We investigated whether DNA alterations in HOX genes, either alone or in combination with RET, are implicated in HSCR. Genotyping effort was minimized by applying the HapMap data on Han Chinese from Beijing (CHB). 194 HSCR patients and 168 controls were genotyped using Sequenom technology for 72 tag, single nucleotide polymorphisms (SNPs) distributed along the HOX clusters. The HapMap frequencies were compared to those in our population and standard statistics were used for frequency comparisons. The multifactor-dimensionality-reduction method was used for multilocus analysis, in which RET promoter SNP genotypes were included. Genetic interactions were found between two HOX loci (5'-HOXA13 and 3'UTR-HOXB7) and the RET loci tested. Minor allele frequencies (MAF) of the SNPs tested in our sample were not significantly different from those reported by HapMap when the sample sizes of the populations compared were considered. This is the first evaluation of the HOX genes in HSCR and the first application of HapMap data in a Chinese population. The interacting HOX loci may affect the penetrance of the RET risk allele. HapMap data for the CHB population correlated well with the general Chinese population.
    Annals of Human Genetics 08/2007; 71(Pt 4):526-36. · 2.57 Impact Factor
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    Article: Inhibition of tumor growth and metastasis in vitro and in vivo by targeting macrophage migration inhibitory factor in human neuroblastoma.
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    ABSTRACT: Macrophage migration inhibitory factor (MIF) has been defined as a novel oncogene. Our previous results have shown that MIF may contribute to the progression of neuroblastoma by (a) inducing N-Myc expression and (b) upregulating the expression of angiogenic factors. The aim of this study was to test whether tumor growth could be inhibited by reduction of endogenous MIF expression in neuroblastoma and clarify the molecular mechanisms underlying MIF reduction on the control of neuroblastoma growth. We established human neuroblastoma cell lines stably expressing antisense MIF (AS-MIF) cDNA. These stable transfectants were characterized by cell proliferation, gene expression profile, tumorigenicity and metastasis in vitro and in vivo. Decreased MIF expression was observed after transfection with AS-MIF in neuroblastoma cells and downregulation of MIF expression significantly correlated with decreased expression of N-Myc, Ras, c-Met and TrkB at protein level. Affymetrix microarray analysis revealed that expression of IL-8 and c-met was inhibited and neuroblastoma-favorable genes such as EPHB6 and BLU were upregulated in MIF reduced cells. Neuroblastoma cell growth exhibited a nearly 80% reduction in AS-MIF transfectants in vitro. Furthermore, mice in which tumors formed after subcutaneous injection of AS-MIF transfectants showed a 90% reduction in tumor growth compared to control. Metastasis in mice was also suppressed dramatically. Our data demonstrate that targeting MIF expression is a promising therapeutic strategy in human neuroblastoma therapy, and also identifies the MIF target genes for further study.
    Oncogene 07/2006; 25(25):3501-8. · 6.37 Impact Factor
  • Article: A simple and secure method to fix laparoscopic trocars in children.
    K F Yip, P K H Tam, M K W Li
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    ABSTRACT: We introduce a simple method of fixing trocars to the abdominal wall in children. Before anchoring the trocar, a piece of Tegaderm polyurethrane adhesive (3M Healthcare, St. Paul, Minnesota) is attached to the trocar. A silk stitch is anchored to neighboring skin, and then transfixed over the shaft of the trocar through the adhesive. Both inward and outward movement of the trocar can be restrained. This method is simple, fast, secure, and can be applied to trocars of any size.
    Journal of Laparoendoscopic & Advanced Surgical Techniques 05/2006; 16(2):188-90. · 1.40 Impact Factor
  • Article: Meconium peritonitis: prenatal diagnosis, postnatal management and outcome.
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    ABSTRACT: Prenatal ultrasonography (USS) is a routine screening test for fetal abnormalities. Its accuracy for detecting meconium peritonitis (MP), which may carry high mortality, is important for prenatal counseling. The aim of this study was to assess the accuracy of prenatal USS for diagnosing MP and predicting patient outcomes. The prenatal and postnatal medical records of all patients referred to our institutions with confirmed MP were reviewed, with emphasis on prenatal USS findings, results of postnatal investigations, operative findings, outcomes, and possible causes of MP. From January 2000 to November 2004, seven fetuses were confirmed to have MP at birth. Three MP patients (3/7, 43%) were diagnosed prenatally because of USS showing ascites and calcification/dilated or hyperechoic bowel loops. One (1/7, 14.3%) suspected cystic MP was confirmed by prenatal MRI. In the other three cases, USS showed only ascites. All patients had postnatal contrast CT scans. Two patients' CT scans showed persistent intestinal perforation not visible with prenatal USS, and required emergency operations. All patients survived and prospered, and were sweat test negative. Prenatal USS allows suspected MP babies to be transferred to a tertiary centre for delivery and appropriate management. In this way, the chances of survival of these babies can be excellent if they are not associated with cystic fibrosis (CF). Prenatal MRI can improve the low diagnostic yield of prenatal USS for MP. Postnatal contrast CT scan is required to define persistent intestinal perforation invisible with prenatal USS.
    Prenatal Diagnosis 09/2005; 25(8):676-82. · 2.11 Impact Factor
  • Article: Prospective randomized single-center, single-blind comparison of laparoscopic vs open repair of pediatric inguinal hernia.
    K L Chan, W C Hui, P K H Tam
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    ABSTRACT: The repair of indirect inguinal hernia (IH) is one of the most common pediatric surgical procedures, and open surgery (OS) is the standard treatment. The aim of this study was to determine whether the recently developed laparoscopic repair (LR) of IH is superior to OS. Between February 2003 and February 2004, we randomly assigned 97 consecutive IH patients at our institution into OS and LR groups. Fourteen patients were excluded from the study for various reasons, leaving study population of 83 patients. After operation, multiple dressings were placed to blind observers to the operation type. Two pain scales, the children and Infants Postoperative Pain were used to assess postoperative pain. Acetaminophen (15 mg/kg/dose every 6 h) was given at a fixed pain score. Analgesic doses were compared. Parents also provided assessments of their children's recovery and wound appearance. The amount of acetaminophen taken by the OS group (n = 42) was 1.05 +/- 1.248 doses per patient, whereas the amount taken by the LR group (n = 41) was 0.54 +/- 0.84 dose per patient (p = 0.032; 95% confidence interval 0.45-0.976). Laparoscopy detected 11 more bilateral hernias (p = 0.006). Although the operative times did not differ significantly for bilateral hernias (39.08 +/- 13.37 min vs 34.0 +/- 11.31 min, p = 0.623), it did differ for unilateral hernias (18.38 +/- 5.71 vs 23.25 +/- 6.26 min, p = 0.001). Five contralateral hernias were detected in the OS group on follow-up, but none were found in the LR group (p = 0.026). The scores given by parents for recovery and wound appearance were higher in the LR group (p = 0.05). As compared with IH patients who undergo open surgery, those who have a laparoscopic repair suffer less pain, and their recovery and wound cosmesis are more satisfactory. With LR, contralateral hernias can be detected and repaired in a single operative procedure. This procedure takes slightly longer for unilateral than for bilateral hernias.
    Surgical Endoscopy 08/2005; 19(7):927-32. · 4.01 Impact Factor
  • Article: Up-regulation of macrophage migration inhibitory factor in infants with acute neonatal necrotizing enterocolitis.
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    ABSTRACT: To investigate the role of macrophage migration inhibitory factor (MIF) and its downstream cytokine cascade in necrotizing enterocolitis (NEC). The expression of MIF mRNA and protein in NEC guts was assayed by in situ hybridization and immunohistochemistry, respectively. Concentrations of MIF, interleukin (IL)-6 and IL-8 in the serum and in the supernatant of macrophage cultures were examined by ELISA. Increased expression of MIF mRNA and protein was observed in the NEC guts, mainly in the infiltrating macrophages in the mucosa and submucosal layers. Up-regulation of MIF was associated with the accumulation of macrophages and T cells. In addition, serum levels of MIF, IL-6 and IL-8 in NEC patients during the acute stage of the disease were significantly increased. The expression of MIF decreased both locally and systemically after the disease was resolved. MIF was also found to increase the secretion of IL-6 and IL-8 by macrophages isolated from healthy individuals in vitro in NEC. MIF acts by stimulating macrophage production of IL-6 and IL-8. This further aggravates the inflammatory process by increasing the infiltration of neutrophils and activating inflammatory cells. The results of this study suggest that MIF plays an important role in the pathogenesis of NEC and may serve as a target for therapeutic intervention in NEC.
    Histopathology 07/2005; 46(6):659-67. · 3.08 Impact Factor
  • Article: Prospective randomized single-center, single-blind Comparison of laparoscopic vs open repair of pediatric inguinal hernia
    K.L. Chan, W.C. Hui, P.K.H. Tam
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    ABSTRACT: BackgroundThe repair of indirect inguinal hernia (IH) is one of the most common pediatric surgical procedures, and open surgery (OS) is the standard treatment. The aim of this study was to determine whether the recently developed laparoscopic repair (LR) of IH is superior to OS.MethodsBetween February 2003 and February 2004, we randomly assigned 97 consecutive IH patients at our institution into OS and LR groups. Fourteen pateints were excluded from the study for various reasons, leaving study population of 83 patients. After operation, multiple dressings were placed to blind observers to the operation type. Two pain scales, the children and Infants Postoperative Pain were used to assess postoperative pain. Acetaminophen (15 mg/kg/dose every 6 h) was given at a fixed pain score. Analgesic doses were compared. Parents also provided assessments of their children’s recovery and wound appearance.ResultsThe amount of acetaminophen taken by the OS group (n = 42) was 1.05 1.248 doses per patient, whereas the amount taken by the LR group (n = 41) was 0.54 0.84 dose per patient (p = 0.032; 95% confidence interval 0.45–0.976). Laparoscopy detected 11 more bilateral hernias (p = 0.006). Although the operative times did not differ significantly for bilateral hernias (39.08 13.37 min vs 34.0 11.31 min, p = 0.623), it did differ for unilateral hernias (18.38 5.71 vs 23.25 6.26 min, p = 0.001). Five contralateral hernias were detected in the OS group on follow-up, but none were found in the LR group (p = 0.026). The scores given by parents for recovery and wound appearance were higher in the LR group (p = 0.05).ConclusionsAs compared with IH patients who undergo open surgery, those who have a laparoscopic repair suffer less pain, and their recovery and wound cosmesis are more satisfactory. With LR, contralateral hernias can be detected and repaired in a single operative procedure. This procedure takes slightly longer for unilateral than for bilateral hernias.
    Surgical Endoscopy 06/2005; 19(7):927-932. · 4.01 Impact Factor
  • Article: Post-operative magnetic resonance evaluation of children after laparoscopic anorectoplasty for imperforate anus.
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    ABSTRACT: Laparoscopic anorectoplasty (LAR) is a relatively new procedure in the treatment of imperforate anus. Using magnetic resonance imaging (MRI), we evaluated the anatomical features of the anorectal region of children treated with LAR and compared this with conventional posterior sagittal anorectoplasty (PSARP). The findings were correlated with functional outcome. A retrospective review of ten children with the high/intermediate types of imperforate anus underwent LAR between May 2000 and December 2002. MRI of the pelvis was performed post-operatively and a semi-quantitative score was used to assess the degree of sphincter symmetry, peri-rectal fibrosis, and the position of the pull-through rectum. The defecation status of these patients was also recorded. Eight historical patients who had undergone PSARP served as a control group. When compared with PSARP patients, a significantly lower proportion of LAR patients had sphincter asymmetry (40 vs. 100%, p < 0.05) and peri-rectal fibrosis (40 vs. 87.5%, p < 0.05). The positioning of the rectum was, however, central for both groups (90 vs. 87.5%). No statistical correlation was found between defecation status and the degree of sphincter asymmetry or peri-rectal fibrosis. LAR allows more optimal anatomical reconstruction for patients with the high/intermediate types of imperforate anus. However, additional factors that are not correctable by surgery, such as intrinsic innervation deficiency, also influence the clinical outcome.
    International Journal of Colorectal Disease 02/2005; 20(1):33-7. · 2.38 Impact Factor