Quality of life and defecative function 10 years or longer after posterior sagittal anorectoplasty and laparoscopic-assisted anorectal pull-through for anorectal malformation.

PURPOSE: In our center, patients with anorectal malformation, including males with recto-vesical (RV)/recto-bladder neck (RBN)/recto-prostatic urethral (RU) fistulas, and females with recto-vaginal (RV) fistulas have been treated by posterior sagittal anorectoplasty (PSARP) before 2000, and by laparoscopic-assisted anorectal pull-through (LAARP) thereafter. We would like to compare the quality of life (QOL) and long-term defecative function between these two groups of patients 10 years after reconstructive surgery. METHODS: Patients who underwent LAARP between 2001 and 2005 were compared with historical controls treated with PSARP between 1996 and 2000. Degrees of continence were graded by the Krickenbeck classification and Kelly's score. QOL was assessed by Hirschsprung's disease/Anorectal Malformation Quality of Life (HAQL) questionnaire. Results were compared using Chi-square test and t test. RESULTS: There were 14 LAARP and 7 PSARP patients. All attained voluntary bowel movements. Moderate to severe soiling (Krickenbeck Grade 2 and 3) was found in 3/14 LAARP (21.4%) and 1/7 PSARP (14.3%) patients, p = 1.00. Constipation requiring use of laxatives was present in 3/14 LAARP (28.6%) and 1/7 PSARP (14.3%) patients, p = 0.62. Mean Kelly's scores were 3.79 ± 0.98 (LAARP) and 4.71 ± 1.25 (PSARP), p = 0.12. No patient required Malone antegrade continence enema (MACE). The QOL scores based on the HAQL questionnaire were comparable between the two groups in all areas except social functioning, in which the LAARP patients attained a significantly lower mean score (26.4 vs 71.7, p = 0.0001). CONCLUSION: The 10-year outcome between LAARP and PSARP patients in terms of QOL and defecative function is comparable. Impairment in social functioning in these patients is reflected by the self-reported lower level of functioning.

Thoracoscopic repair of congenital diaphragmatic hernia: two centres' experience with 60 patients.

INTRODUCTION: Congenital diaphragmatic hernia is a potentially life-threatening neonatal condition which required surgical intervention. With the advances in endosurgical instruments and techniques, thoracoscopic approach is gaining popularity as a standard procedure in the treatment of this condition. In this study, we reviewed our two centres' experience with thoracoscopic repair of congenital diaphragmatic hernia in recent years. METHODS: All patients who underwent thoracoscopic repair of congenital diaphragmatic hernia between 2010 and 2013 at the two tertiary referral centres were identified. Medical records were retrospectively reviewed. Data including patients' demographics, peri-operative outcomes, length of hospitalisation and post-operative complications were extracted and analysed. RESULTS: 60 patients were identified over the study period, with 46 males and 14 females. 48 patients received operation within the first 7 days of life. There were seven patients with delayed presentation and were operated after 1 month old. The average body weight was 3.03 kg. Left-sided hernia was more prevalent (n = 50). The mean operative time was 88.5 min (range 31-194 min). No conversion to open thoracotomy or laparotomy was required in any of the patients. All patients except one were intubated and paralysed in neonatal intensive care units for at least 3 days after operation. Average hospital stay was 14.6 days. There was no mortality in this series. There were five recurrences, one being the patient without post-operative paralysis, and the others with deficient posterior muscle rim. No musculoskeletal deformity was noted on follow-up examination. CONCLUSION: Thoracoscopic repair of congenital diaphragmatic hernia can be performed safely in specialised centres. The post-operative recovery and cosmesis are excellent. Diaphragmatic hernia with large defect remains a challenge for surgeons.

The value of the 24-h delayed abdominal radiograph of barium enema in the diagnosis of Hirschsprung's disease.

AIM OF STUDY: The objective of this study is to determine the diagnostic value of the 24-h delayed film for Hirschsprung's disease (HD). Other features of the barium enema were also examined, in particular the correlation between the radiological transition zone (TZ) and the final pathology. METHODS: All patients with suspected HD from 2003 to 2013 who had undergone barium enema and rectal biopsy were reviewed retrospectively to study the correlation between radiological features of barium enema with the final diagnosis as well as severity. RESULTS: A total of 182 patients were admitted for suspected HD during the study period, of which 82 had both investigations done. 68 patients had radiological features suggestive of the disease and ultimately, 12 patients had the disease confirmed with rectal biopsy. Among those without radiological features of HD, 2 patients were found to have the disease. Thus, the sensitivity of the 24-h delayed film was 85.7 % and the specificity was 17.6 %. The positive predictive value (PPV) of this test was 20.6 % and the negative predictive value (NPV) was 85.7 %. Regarding the level of TZ, it was not detected in the barium enema in 7 (50 %) out of the 14 patients. For those with the presence of TZ, 6 (85.7 %) of them correlated well with the intra-operative findings and 4 (57.1 %) of them correlated well with the final histology. CONCLUSION: The 24-h delayed film of barium enema has a high NPV and is useful to rule out HD. However, rectal biopsy is still suggested for disease confirmation given its low PPV. Lastly, once present, the level of radiological TZ is also a useful predictor for the actual disease involvement.

Prokineticin signaling is required for the maintenance of a de novo population of c-KIT⁺ cells to sustain neuroblastoma progression.

High cellular heterogeneity within neuroblastomas (NBs) may account for the non-uniform response to treatment. c-KIT(+) cells are frequently detected in NB, but how they influence NB behavior still remains elusive. Here, we used NB tumor-initiating cells to reconstitute NB development and demonstrated that c-KIT(+) cells are de novo generated and dynamically maintained within the tumors to sustain tumor progression. c-KIT(+) NB cells express higher levels of neural crest and stem cell markers (SLUG, SOX2 and NANOG) and are endowed with high clonogenic capacity, differentiation plasticity and are refractory to drugs. With serial transplantation assays, we found that c-KIT expression is not required for tumor formation, but c-KIT(+) cells are more aggressive and can induce tumors ninefold more efficiently than c-KIT(-/low) cells. Intriguingly, c-KIT(+) cells exhibited a long-term in vivo self-renewal capacity to sustain the formation of secondary and tertiary tumors in mice. In addition, we showed that Prokineticin signaling and mitogen-activated protein kinase pathways are crucial for the maintenance of c-KIT(+) cells in tumor to promote NB progression. Our results highlight the importance of this de novo population of NB cells in sustainable growth of NB and reveal specific signaling pathways that may provide targets leading to more effective NB therapies.

Dysregulation of Wnt inhibitory factor 1 (Wif1) expression resulted in aberrant Wnt-ß-catenin signaling and cell death of the cloaca endoderm, and anorectal malformations.

In mammalian urorectal development, the urorectal septum (urs) descends from the ventral body wall to the cloaca membrane (cm) to partition the cloaca into urogenital sinus and rectum. Defective urs growth results in human congenital anorectal malformations (ARMs), and their pathogenic mechanisms are unclear. Recent studies only focused on the importance of urs mesenchyme proliferation, which is induced by endoderm-derived Sonic Hedgehog (Shh). Here, we showed that the programmed cell death of the apical urs and proximal cm endoderm is particularly crucial for the growth of urs during septation. The apoptotic endoderm was closely associated with the tempo-spatial expression of Wnt inhibitory factor 1 (Wif1), which is an inhibitor of Wnt-ß-catenin signaling. In Wif1(lacZ/lacZ) mutant mice and cultured urorectum with exogenous Wif1, cloaca septation was defective with undescended urs and hypospadias-like phenotypes, and such septation defects were also observed in Shh(-/-) mutants and in endodermal ß-catenin gain-of-function (GOF) mutants. In addition, Wif1 and Shh were expressed in a complementary manner in the cloaca endoderm, and Wif1 was ectopically expressed in the urs and cm associated with excessive endodermal apoptosis and septation defects in Shh(-/-) mutants. Furthermore, apoptotic cells were markedly reduced in the endodermal ß-catenin GOF mutant embryos, which counteracted the inhibitory effects of Wif1. Taken altogether, these data suggest that regulated expression of Wif1 is critical for the growth of the urs during cloaca septation. Hence, Wif1 governs cell apoptosis of urs endoderm by repressing ß-catenin signal, which may facilitate the protrusion of the underlying proliferating mesenchymal cells towards the cm for cloaca septation. Dysregulation of this endodermal Shh-Wif1-ß-catenin signaling axis contributes to ARM pathogenesis.

Perturbation of Hoxb5 signaling in vagal and trunk neural crest cells causes apoptosis and neurocristopathies in mice.

Neural crest cells (NCCs) migrate from different regions along the anterior-posterior axis of the neural tube (NT) to form different structures. Defective NCC development causes congenital neurocristopathies affecting multiple NCC-derived tissues in human. Perturbed Hoxb5 signaling in vagal NCC causes enteric nervous system (ENS) defects. This study aims to further investigate if perturbed Hoxb5 signaling in trunk NCC contributes to defects of other NCC-derived tissues besides the ENS. We perturbed Hoxb5 signaling in NCC from the entire NT, and investigated its impact in the development of tissues derived from these cells in mice. Perturbation of Hoxb5 signaling in these NCC resulted in Sox9 downregulation, NCC apoptosis, hypoplastic sympathetic and dorsal root ganglia, hypopigmentation and ENS defects. Mutant mice with NCC-specific Sox9 deletion also displayed some of these phenotypes. In vitro and in vivo assays indicated that the Sox9 promoter was bound and trans-activated by Hoxb5. In ovo studies further revealed that Sox9 alleviated apoptosis induced by perturbed Hoxb5 signaling, and Hoxb5 induced ectopic Sox9 expression in chick NT. This study demonstrates that Hoxb5 regulates Sox9 expression in NCC and disruption of this signaling causes Sox9 downregulation, NCC apoptosis and multiple NCC-developmental defects. Phenotypes such as ENS deficiency, hypopigmentation and some of the neurological defects are reported in patients with Hirschsprung disease (HSCR). Whether dysregulation of Hoxb5 signaling and early depletion of NCC contribute to ENS defect and other neurocristopathies in HSCR patients deserves further investigation.

Thoracoscopic resection of congenital cystic lung lesions is associated with better post-operative outcomes.

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.

Laparoscopic inguinal hernia repair in premature neonates: is it safe?

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.

Krüppel-like factor 4 (KLF4) suppresses neuroblastoma cell growth and determines non-tumorigenic lineage differentiation.

Neuroblastoma (NB) is an embryonal tumor and possesses a unique propensity to exhibit either a spontaneous regression or an unrestrained growth. However, the underlying mechanism for this paradoxical clinical outcome remains largely unclear. Quantitative RT-PCR analysis on 102 primary NB tumors revealed that lower Krüppel-like factor 4 (KLF4) expression is frequently found in the unfavorable NB (Mann-Whitney test, P=0.027). In particular with the high-risk factors such as age of patient >1 year, MYCN amplification and low TRKA expression, the decreased expression of KLF4 was significantly associated with an unfavorable NB outcome. Despite knockdown of KLF4 alone is not sufficient to increase tumorigenicity of NB cells in vivo, stable expression of KLF4 short hairpin RNA in Be(2)-C cells significantly promoted growth of NB cells and inhibited cell differentiation toward fibromuscular lineage. In concordant with these observations, overexpression of KLF4 in SH-SY-5Y cells profoundly suppressed cell proliferation by direct upregulation of cell-cycle inhibitor protein p21(WAF1/CIP1), and knocking down p21(WAF1/CIP1) could partially rescue the suppressive effect of KLF4. Importantly, KLF4 overexpressing cells have lost their neuroblastic phenotypes, they were epithelial-like, strongly substrate-adherent, expressing smooth muscle marker and became non-tumorigenic, suggesting that KLF4 expression is crucial for lineage determination of NB cells, probably, favoring spontaneous tumor regression. Subsequent global gene expression profiling further revealed that transforming growth factor beta (TGFß) and cell-cycle pathways are highly dysregulated upon KLF4 overexpression, and myogenic modulators, MEF2A and MYOD1 were found significantly upregulated. Taken together, we have demonstrated that KLF4 contributes to the favorable disease outcome by directly mediating the growth and lineage determination of NB cells.

Thoracoscopic repair of oesophageal atresia: experience of 33 patients from two tertiary referral centres.

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 2.58 kg. The mean operative time was 146 min. 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 3 months 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.

Association of CD247 with systemic lupus erythematosus in Asian populations.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

The potency of allospecific Tregs cells appears to correlate with T cell receptor functional avidity.

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.

Two missense variants in UHRF1BP1 are independently associated with systemic lupus erythematosus in Hong Kong Chinese.

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.

Performing Kasai portoenterostomy beyond 60 days of life is not necessarily associated with a worse outcome.

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.

Fine mapping of the 9q31 Hirschsprung's disease locus.

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.

The first report of a single-port laparoscopic nephrectomy in a child.

There has been an exponential rise in the use of minimally invasive procedures in surgery, with obvious benefits to patients. Recently, transumbilical single-port laparoscopic surgery has been championed as the next major technical advance. In this article, we report the first case where single-port laparoscopic surgery has been used to manage a paediatric problem in the region.

Clinical experience in managing pediatric patients with ultra-short bowel syndrome using omega-3 fatty acid.

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.