Kim Hung Lee

Initial experience in children using conventional laparoscopic instruments in single-incision laparoscopic surgery

BACKGROUND Single-incision laparoscopic surgery (SILS) has been successfully performed in children using 5-mm reticulating instruments. There are, however, few reports investigating the use of conventional instruments in SILS in the pediatric population. METHODS We conducted a retrospective review of all consecutive children who underwent SILS from October 2009 to January 2010, with the procedure being solely performed by conventional 3- and 5-mm instruments through a standard access technique. RESULTS A total of 19 SILS procedures were successfully performed in children aged 3 to 15 years. They included appendectomy (n = 10), nephrectomy (n = 1), combined cholecystectomy and splenectomy (n = 2), cholecystectomy (n = 1), high ligation for varicocele (n = 2), excision of Meckel diverticulum (n = 1), and staged orchidopexy and exploration for impalpable testis (n = 2). There was one conversion to conventional laparoscopic surgery, and that occurred in our first case of splenectomy. All the patients had smooth recovery from surgery without complications. CONCLUSIONS Using conventional instruments in SILS is technically feasible in children from simple to complex procedures and may have the potential to popularize this approach by eliminating the mandatory demand for specially designed instruments.

Rescue treatment of infants with intestinal failure and parenteral nutrition-associated cholestasis (PNAC) using a parenteral fish-oil-based lipid

Four preterm infants with intestinal failure and severe parenteral nutrition-associated cholestasis (PNAC) received fish-oil-based parenteral lipid as rescue treatment in substitution for the standard soybean-based lipid preparation. The progression of liver disease was halted in 3 infants and they recovered with complete resolution of PNAC. The condition in two of these infants would almost certainly have progressed to end-stage hepatic failure if they had continued to receive long-term parenteral nutrition and <30% of total nutrition enterally. The remaining infant with residual inflamed bowel, protracted feeding intolerance and repeated episodes of sepsis did not respond. Our findings suggest that fish-oil-based parenteral lipid emulsion may contribute to effective treatment of PNAC in selected patients, which should be further evaluated in randomized controlled trials.

Testicular catch-up growth after varicocele correction in adolescents.

Abstract We evaluated retrospectively the outcome of artery-sparing (AS) versus non-artery-sparing (NAS) laparoscopic varicocelectomy and measured any reversal of testicular growth. Twenty patients (13 left and 7 bilateral varicoceles) were evaluated after surgery. A total of 27 varicocelectomies (20 AS and 7 NAS) were performed. The indication for surgery was smaller testicular size on the affected side in all patients and discomfort/pain in 3. The mean age was 12.9 years (range 8–15 years) at surgery. The testicular volumes were determined clinically and by color Doppler sonography (US). The follow-up time was 6–48 months after surgery. There were 4 recurrences out of 27 varicocelectomies (15%), of which 1 has been reoperated. Testicular volumes were equal in both groups after surgery, indicating catch-up growth except in the cases with minor recurrences (2 AS and 2 NAS varicocelectomies). In 12 testes, dilated veins in the pampiniform plexus were revealed by US. No severe intraoperative complications occurred. Three patients had a hydrocele after surgery (11%). These data show that there is testicular catch-up growth after varicocelectomy, but some questions remain unanswered: (1) should the remaining dilated veins detected by Doppler US be tackled; and (2) is an AS operation worthwhile?

A double-blind randomised controlled trial of fish oil-based versus soy-based lipid preparations in the treatment of infants with parenteral nutrition-associated cholestasis.

Background: Infants receiving prolonged parenteral nutrition (PN) are at risk of PN-associated cholestasis (PNAC). This can progress to hepatic failure and death if PN cannot be discontinued. Fish oil-based parenteral lipid preparation (FOLP) has been shown to be beneficial in case studies. Objectives: (1) To evaluate whether FOLP could halt or reverse the progression of PNAC compared with soy-based parenteral lipid preparation (SLP) and (2) to assess the effects of FOLP on liver function and physical growth. Methods: Design: double-blind randomised controlled trial. Setting: level III neonatal intensive care unit. Participants: infants with PNAC (plasma-conjugated bilirubin concentration ≥34 µmol/l or 2 mg/dl) expected to be PN-dependent for >2 weeks. Intervention: to receive either FOLP or SLP at 1.5 g/kg/day. Primary outcome measure: reversal of PNAC within 4 months after commencement of lipid treatment; secondary outcomes: rate of change of weekly liver function tests, infant growth parameters, blood lipid profile and episodes of late-onset sepsis. Results: A total of 9 infants were randomised to the FOLP group and 7 to the SLP group. There was no significant difference in reversal of PNAC at 4 months between groups. Rates of increase of plasma-conjugated bilirubin and alanine aminotransferase in the SLP group were significantly greater than the FOLP group (13.5 vs. 0.6 µmol/l per week and 9.1 vs. 1.1 IU/l per week, respectively, p = 0.03). Increased enteral nutrition was associated with significant improvement of PNAC in infants receiving FOLP compared with SLP (-8.5 vs. -1.6 µmol/l per 10% increase in enteral nutrition, respectively). The study was terminated prematurely. Conclusions: progression of PNAC in PN-dependent infants can be halted by replacing SLP with FOLP and reversed by increasing the proportion of enteral nutrition in infants receiving FOLP. Replacement of SLP with FOLP in PN-dependent infants who develop PNAC may be considered.

Immunoregulatory Protein Profiles of Necrotizing Enterocolitis versus Spontaneous Intestinal Perforation in Preterm Infants

Necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) are the most common acute surgical emergencies associated with high morbidity and mortality in preterm infants. We aimed to compare the profiles of immunoregulatory proteins and identify novel mediators in plasma of NEC and SIP infants. We also investigated the expression of target genes in resected intestinal tissues and an enterocyte cell line. Using Cytokine Antibody Array assay, we reported the first comparative profiles of immunoregulatory proteins in plasma of NEC and SIP infants, and showed that dysregulated proteins belonged to functionally diversified categories, including pro- and anti-inflammation, angiogenesis, cell growth, wound healing, anti-apoptosis, cell adhesion and extracellular matrix reorganization. Validation by ELISA confirmed significantly higher concentrations of interleukin (IL)-6, angiopoietin (Ang)-2, soluble type II interleukin-1 receptor (sIL-1RII), and soluble urokinase-type plasminogen activator receptor (suPAR) in NEC infants compared with gestational age-matched control, and a lower level of an epidermal growth factor receptor, secreted form of receptor tyrosine-protein kinase ErbB3 (sErbB3), compared with SIP infants. mRNA expressions of IL1-RII and uPAR were up-regulated in resected bowel tissues from NEC infants, indicating that immunoregulation also occurred at the cellular level. In FHs-74 Int cells, Ang-2, IL1-RII and uPAR mRNA expressions were significantly induced by the combined treatment with lipopolysaccharide (LPS) and platelet activating factor (PAF). Our study provided plasmatic signatures of immunoregulatory proteins in NEC and SIP infants, and demonstrated involvement of multiple functional pathways. The magnitude of changes in these proteins was significantly more extensive in NEC infants, reflecting the different nature of injury and/or severity of inflammation. We speculate that dysregulation of IL-6, Ang-2, IL-1RII and uPAR occurred at both systemic and cellular levels, and probably mediated via LPS and endogeneous PAF signals. Such exaggerated immunologic responses may account for the high morbidity and mortality in NEC compared with SIP patients.

Genome-wide expression profiles of necrotizing enterocolitis versus spontaneous intestinal perforation in human intestinal tissues: dysregulation of functional pathways.

Objective:To provide a comprehensive database of gene regulation and compare differentially regulated molecular networks in human tissues of necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP). Background:Both NEC and SIP are devastating surgical emergencies associated with high morbidity and mortality in preterm infants. Their pathophysiology and molecular mechanisms remain unclear. Methods:Differential whole genome microarray analysis was performed on intestinal tissues collected from NEC (n = 15) and SIP (n = 12) infants and compared with tissues collected from surgical-control patients with noninflammatory intestinal conditions (n = 14). Validation of 52 target gene expressions was performed by quantitative polymerase chain reaction. Regulatory networks of significantly affected genes were constructed according to functional pathways. Results:Extensive and significant changes of gene expression were observed in NEC tissues, which comprised multiple pathways of angiogenesis, arginine metabolism, cell adhesion and chemotaxis, extracellular matrix remodeling, hypoxia and oxidative stress, inflammation, and muscle contraction. These dysregulated genes could be networked downstream of key receptors, TLR2, TLR4, and TREM1, and mediated via NF-&kgr;B, AP-1, and HIF1A transcription factor pathways, indicating predominant microbial and inflammatory involvement. In contrast, SIP tissues exhibited much milder and less diversified expressional changes, with target genes significantly associated with G-protein–mediated muscle contraction and extracellular matrix remodeling. Conclusions:The molecular evidence suggests that NEC and SIP are likely 2 different diseases caused by distinct etiology and pathophysiology. This first comprehensive database on differential gene expression profiles of human NEC and SIP tissues could lead to development of disease-specific diagnostic and prognostic biomarkers and new therapeutic strategies for improving outcomes.

Helicobacter pylori-positive versus Helicobacter pylori-negative idiopathic peptic ulcers in children with their long-term outcomes.

Objectives:The aim of this study is to investigate the differences in the characteristics between Helicobacter pylori–positive and H pylori–negative primary ulcers in Chinese children. Patients and Methods:We conducted a retrospective review of children with primary peptic ulcers. Demographic data, clinical presentations, endoscopic features, histological findings, H pylori prevalence, and ulcer recurrences were studied. Results:Forty-three Chinese children with primary peptic ulcers were diagnosed over 8 years and were reviewed. There were 31 boys and 12 girls (median age 12 years, range 3–16 years). Thirty children (70%) presented with acute gastrointestinal bleeding, whereas only 19 had a history of epigastric pain. Twenty-three patients (53.5%) were H pylori positive. H pylori–positive ulcers developed in older children (median age 12 vs 10 years, P < 0.05) and affected more males (91.3% vs 50%, P < 0.01) than the H pylori–negative group. The annual ulcer recurrence rates were estimated to be 5.2% (95% CI 4.2–6.3) and 11.4% (95% CI 9.1–13.6) for positive and negative groups, respectively (P < 0.05). Multivariate logistic regression suggested H pylori–negative status and ulcer size >1 cm were independent risk factors for recurrence. Conclusions:Our report suggests that H pylori–negative primary ulcers exist in children with their own distinct features. In contrast to H pylori–positive ulcers, H pylori–negative ulcers develop in younger children, affect both sexes equally, and carry a higher recurrence risk.

A population-based study of Helicobacter pylori infection in Chinese children resident in Hong Kong: prevalence and potential risk factors.

Background:  Data of Helicobacter pylori prevalence in children and its risk factors provide clues to the health authority to estimate burden of H. pylori‐associated diseases usually encountered in adulthood and facilitate healthcare planning.

Laparoscopic hernia repair in children by the hook method: a single-center series of 433 consecutive patients

BACKGROUND The relatively high recurrence rate reported in laparoscopic hernia repair in children using intracorporeal suturing technique remains a concern. We aimed to investigate the effectiveness of the hook method during hernia repair that allows extraperitoneal passage of suture to close the hernia sac without creating any tension or skip areas and does not require laparoscopic suturing skills. METHODS A retrospective review was conducted on 433 consecutive children who underwent laparoscopic hernia repair using the hook method by 1 of 4 surgeons from July 2004 to June 2007. RESULTS A total of 572 successful laparoscopic hernia repairs were performed among the 433 children with an age range of 1 week to 15 years (mean = 56 months). Conversion rate was 1.04%. Contralateral patent processus vaginalis was found in 26.8%. Mean operating time was 23.8 and 40.2 minutes for unilateral and bilateral repair, respectively. At a median follow-up of 20 months, there were 2 recurrences (0.35%), 2 hydroceles, 1 ascending testis, and 1 instance of testicular atrophy. No serious complications were associated with the procedure. CONCLUSIONS Medium-term results suggest that laparoscopic hernia repair with the hook method is a sound alternative to open herniotomy in children.

Socioenvironmental Factors Associated With Constipation in Hong Kong Children and Rome III Criteria

Objective: Data regarding the prevalence of constipation in the general population of Asian children using internationally standardized definitions are scarce. Environmental factors surrounding a childs day to day living may trigger or perpetuate constipation and encourage postponement of defecation. Methods: A territory-wide cross-sectional questionnaire survey was conducted in 2318 Hong Kong Chinese elementary school students. Constipation was defined by pediatric Rome III criteria. Results: The mean age of the children was 9 ± 1.9 years; 51% were boys. Two hundred eighty-two children (12.2%, 95% confidence interval [CI] 10.9%–13.5%) were found to have constipation. Children ages 6 to 7 years had the highest prevalence (16.8%, 95% CI 13.8%–19.8%). There was no difference in prevalence between boys and girls (11.6% vs 12.3%; P > 0.05) and between obese and nonobese children (11.5% vs 11.1%; P > 0.05). In univariate analysis, constipation was found to be significantly more prevalent among those children who lived with neither parent, had inadequate company of parents at home, refused to pass bowel movements in school, spent long hours doing homework, had inadequate sleep, and had decreased fiber intake and frequent consumption of fast food (P < 0.05). Multivariate analysis identified refusal to pass bowel movements in school toilets (odds ratio [OR] 1.97, 95% CI 1.42%–2.74%), having dinner with one/both parents <50% of time (OR 1.52, 95% CI 1.01%–2.31%), nighttime sleep <7 hours (OR 1.87, 95% CI 1.04%–3.33%), and frequent consumption of fast food (OR 1.14, 95% CI 1.03%–1.26%) to be independent factors associated with constipation. Conclusions: Socioenvironmental factors are associated with childhood constipation, and bringing them to the awareness of the public may help prevent or stop the progression of childhood constipation at its early stages.