Total colonic Hirschsprung's disease: a 28-year experience

PURPOSE

The aim of this study was to review outcomes after surgical treatment of total colonic Hirschsprung's disease (TCH).

METHODS

Twenty-five records of patients with TCH treated between 1974 and 2002 were reviewed. Follow-up data were collected using a standardized questionnaire. Objective functional outcome was assessed using a scoring system.

RESULTS

Twenty patients had aganglionosis of the colon and distal ileum, 5 of whom had a more extensive condition. One of these 5 patients underwent an endorectal pull-through (ERPT), 1 underwent intestinal transplantation, and 3 died. Four of the remaining 20 patients underwent a primary ERPT, 16 received a stoma as neonates followed by ERPT in 12, and a Martin-Duhamel procedure or Swenson's operation in 3 (median age, 10.5 months); 1 remains with an ostomy. Postoperative complications included enterocolitis (55%), anal stricture (25%), and perineal excoriation (20%). Mean follow-up were 17.5 years (+/-11.1 years). Eighty-nine percent were free of recurrent enterocolitis. Frequency of bowel movements is 1 to 5 per day in 82% of the patients, 18% have 6 or more bowel movements per day. Occasional soiling is noted in 40% (one third of those requiring nighttime diapers). Overall functional outcome was good in 83%. Those patients with the longest follow-up periods had the best stooling scores (P = .04).

CONCLUSIONS

Surgical treatment of TCH is associated with a number of complications including recurrent enterocolitis and anal strictures. Long-term outcome is quite favorable.

The effect of phenol on ingrown toenail excision in children

PURPOSE

Ingrown toenails in children are a common problem with a high recurrence rate. The objective of this retrospective data review was to compare simple excision of the nail matrix with excision plus phenol (EPP) application in the treatment of ingrown toenails.

METHODS

The charts of 69 children who underwent surgical treatment of one or more ingrown toenails from 1994 to 2000 were reviewed. The primary procedure was noted (excision alone [EA] vs EPP) and dates of recurrences and reoperations were recorded. Parents were then surveyed by phone regarding complications, cosmetic outcome, and overall satisfaction with the procedure. Five scale categories, ranging from "strongly agree" to "strongly disagree", were used, with responses of "strongly agree" and "agree" considered as a good outcome. Either Student's t test or the chi2 test (P < .05 considered significant) was used for analysis.

RESULTS

Thirty-one patients (45%) were in the EPP group whereas the remaining 38 had EA. Mean length of follow-up was 4.3 years for the EA group and 2.1 years for the EPP group. There was no difference in age at operation or length of follow-up between the 2 groups. Boys were predominant in both groups. The survey response rate was 50/69 (73%). The recurrence rate of ingrown toenails in the EA group was 42% vs 4% in the EPP group (P = .003). There were no significant differences in parental response with regard to operative experience (P = .31) and the cosmetic result (P = .13), with most of the respondents (78%) indicating a good outcome for both questions.

CONCLUSIONS

The addition of phenol to the surgical excision of ingrown toenail significantly reduced the incidence of recurrence, with similar patient satisfaction and an equivalent cosmetic result.

Oral arginine reduces gut mucosal injury caused by lipopolysaccharide endotoxemia in rat

BACKGROUND

The objective of this study was to evaluate the effects of lipopolysaccharide (LPS) endotoxemia and enteral arginine (ARG) supplementation on intestinal structural changes, enterocyte proliferation, and apoptosis in rat.

METHODS

Male Sprague-Dawley rats, weighing 250-280 g, were divided into three experimental groups: control rats, LPS rats treated with lipopolysaccharide given ip at a dose of 10 mg/kg every 24 h (two injections), and LPS-ARG rats treated with enteral arginine given in drinking water (2%) 72 h before and following injection of LPS. Intestinal structural changes, enterocyte proliferation, and enterocyte apoptosis were determined on day 3 following the first LPS injection.

RESULTS

LPS rats demonstrated a significant decrease in bowel weight in duodenum, mucosal weight in duodenum, jejunum, and ileum, mucosal DNA and protein in jejunum and ileum, and villus height in jejunum and ileum compared to control animals. LPS rats also had a significantly lower cell proliferation index in jejunum and ileum and a higher apoptotic index in jejunum and ileum compared to control rats. LPS-ARG animals demonstrated greater duodenal bowel weight, duodenal and ileal mucosal weight, ileal mucosal DNA and protein, ileal villus height, and jejunal and ileal cell proliferation index compared to LPS animals.

CONCLUSIONS

LPS endotoxemia impairs the integrity of the gastrointestinal mucosa in rat. Decreased cell proliferation and increased apoptosis may be considered the main mechanisms responsible for the decreased cell mass. Enteral arginine administration decreases the mucosal injury caused by lipopolysaccharide.

Splenic Artery Embolization for Post-Traumatic Splenic Artery Pseudoaneurysm in Children

Although rare, traumatic splenic artery pseudoaneurysm (SAP) can be life threatening. The diagnostic approaches as well as the methods of treatment of SAP are yet to be determined. We present the case of a 10-year-old boy treated conservatively for a grade III blunt splenic injury (BSI). The child was discharged to home after a 5-day uneventful hospitalization but was found on routine follow-up CT scan to have a large SAP. The pseudoaneurysm was successfully angiographically embolized and subsequent abdominal CT demonstrated successful resolution of the pseudoaneurysm with a small residual splenic cyst. We reviewed the eight cases of post-traumatic SAP in children that have been published in the English literature. Unlike SAP in adult patients, the severity of the splenic injury does not have predictive value for development of SAP in children. Abdominal pain was the most frequent symptom of SAP, but three children were asymptomatic at the time of diagnosis. Therefore, the possibility of SAP should be investigated even in the asymptomatic child with mild splenic injury. When a splenic pseudoaneurysm is diagnosed, we believe splenic artery embolization is indicated.

Severe esophageal damage due to button battery ingestion: can it be prevented?

Batteries represent less than 2% of foreign bodies ingested by children, but in the last 2 decades, the frequency has continuously increased. Most ingestions have an uneventful course, but those that lodge in the esophagus can lead to serious complications and even death. Medline was used to search the English medical literature, combining "button battery" and "esophageal burn" as keywords. Cases were studied for type, size, and source of the batteries; duration and location of the battery impaction in the esophagus; symptoms; damage caused by the battery; and outcome. Nineteen cases of esophageal damage have been reported since 1979. Batteries less than 15 mm in diameter almost never lodged in the esophagus. Only 3% of button batteries were larger than 20 mm but were responsible for the severe esophageal injuries in this series. These data suggest that manufacturers should replace large batteries with smaller ones and thus eliminate most of the complications. When the battery remains in the esophagus, endoscopic examination and removal done urgently will allow assessment of the esophageal damage, and treatment can be tailored accordingly. There is a need for more public education about the dangers of battery ingestion; this information should be included as part of the routine guidelines for childproofing the home.

Effect of dietary fat on early morphological intestinal adaptation in a rat with short bowel syndrome

Among factors promoting mucosal hyperplasia after bowel resection, long-chain fatty acids may have a special role. The purpose of the present study was to evaluate the effects of high-fat diet (HFD) on early intestinal adaptation in rats with short bowel syndrome (SBS). Male Sprague-Dawley rats underwent either a bowel transection with re-anastomosis (Sham rats) or 75% small bowel resection (SBS rats). Animals were randomly assigned to one of three groups: Sham rats fed normal chow (Sham-NC); SBS rats fed NC (SBS-NC); and SBS rats fed HFD (SBS-HFD). Rats were killed on days 3 or 14. Body weight and parameters of intestinal adaptation (overall bowel and mucosal weight, mucosal DNA and protein, villus height, and crypt depth) were determined at time of killing. By day 3, SBS-HFD rats demonstrated higher duodenal and jejunal bowel and mucosal weights and ileal villus height and jejunal crypt depth vs SBS-NC rats. By day 14 SBS-HFD rats continued to demonstrate increased duodenal and jejunal bowel weight and duodenal mucosal weight vs SBS-NC animals. We conclude that early exposure to HFD both augmented and accelerated structural bowel adaptation in a rat model of SBS.

Posterior myotomy/myectomy for persistent stooling problems in Hirschsprung's disease

BACKGROUND

Hirschsprung's disease (HD) patients after pull-through (PT) may have recalcitrant constipation or recurrent enterocolitis (EC). Posterior myotomy/myectomy (POMM) are possible options for these problems. This study analyzed the outcome of POMM in HD patients post-PT.

METHODS

Records of 348 HD patients were reviewed, and 32 were found to have undergone a POMM post-PT (1981 to 2002). Outcomes after this procedure were assessed. Statistics used linear and logistic regression.

RESULTS

Of the 32 patients, 29 had complete records for analysis. Of those with pure constipation (12), 6 had aganglionosis post-PT. Of those with recurrent EC (17) only 1 had aganglionosis post-PT. POMM was performed at a mean of 3.1 years post-PT (11 myotomy, 18 myectomy). Average follow-up was 8.6 years (range, 0.7 to 21). Type of POMM had no correlation with overall functional outcome (P =.44). Of those with chronic constipation, 60% had good results after POMM; the remainder required a redo-PT or colostomy. Interestingly, most patients with retained aganglionosis and chronic constipation did not respond after POMM (83%). Of those with recurrent EC, 75% became free of symptoms; none of the patients not responding have required redo-PT.

CONCLUSIONS

POMM to treat chronic constipation or recurrent EC in patients with HD post-PT is moderately successful. Because of the unsuccessful outcome with POMM in patients with a combination of constipation and aganglionosis, one should defer to a redo-PT in this group.

Effects of lipid administration on liver apoptotic signals in a mouse model of total parenteral nutrition (TPN)

Lipids are an important component of total parenteral nutrition (TPN), contributing the largest caloric load per volume of solution and providing essential fatty acids necessary for survival. However, lipids are known to be causative factors in oxidative stress, which are expressed via the Bcl-2 family of proteins and/or Fas-mediated apoptosis in several tissues. Interestingly, we have recently observed an increase in hepatocyte apoptosis with administration of TPN. To address the mechanism of this apoptosis, we investigated the effects of parenteral lipid administration on apoptotic signaling in a mouse model. C57BL/6J male mice received physiologic saline and standard chow (control) or standard TPN solution with (TPN+L) or without lipid (TPN-L) emulsion. After 7 days of infusion, apoptosis increased in the TPN+L at a significantly higher rate compared with control and TPN-L groups ( p<0.05). Both TPN, with and without lipids, suppressed the pro-apoptotic signals Bid and Bcl-xs ( p<0.05). In contrast, TPN with lipid increased the expression of Fas and both the pro-apoptotic factor Bad and the anti-apoptotic factor Bcl-xl ( p<0.05). These changes may contribute to TPN-induced hepatocyte injury (apoptosis) or suppress the ability of liver hepatocytes to regenerate.

A novel approach to the management of late-onset liver failure in biliary atresia

PURPOSE

Late-onset hyperbilirubinemia in patients who have undergone a successful portoenterostomy (PE) for biliary atresia (BA) is usually considered evidence of ongoing severe liver failure. The authors recently have treated 2 patients who had acute hyperbilirubinemia years and months after a successful PE and had dilated intrahepatic cysts. A combined operative and percutaneous approach reestablished drainage and a reduction in their bilirubin levels.

METHODS

Data from 2 cases of BA and late-onset hyperbilirubinemia from obstruction were reviewed and analyzed.

RESULTS

Two patients (15-year-old boy and a 2.5-year-old girl) presented with increasing serum bilirubin after a PE for BA in infancy. Both had extensive preoperative workup, which showed intrahepatic biliary dilatation in one and a large bile lake in the other. They underwent attempted percutaneous transhepatic cholangiography and stenting, followed by an intraoperative transhepatic approach in which the dilated ducts were connected to the PE. A rapid and sustained reduction in the serum bilirubin level was noted in these patients.

CONCLUSIONS

When patients with BA after a successful PE present with sudden onset of hyperbilirubinemia, imaging for biliary obstruction should be carried out. If biliary dilatation is found, then a combined radiologic and operative approach may help improve the bile flow and delay the need for liver transplant.

Delayed versus immediate surgery in acute appendicitis: do we need to operate during the night?

BACKGROUND/PURPOSE

Over the last 4 years, the authors changed their management of acute nonperforated appendicitis from emergent surgery within the first 2 to 6 hours of admission to initiation of antibiotic therapy with operation within 24 hours of admission in those seen in the late evening or early morning. They examined, therefore, whether a delay in operation for acute appendicitis would affect outcome measures of patient morbidity and resource use.

METHODS

The medical records of 126 patients with acute appendicitis occurring between 1998 and 2001 were retrospectively reviewed. Incidence of perforation at surgery, length of stay (LOS), hospital charges, operating time, and complications as a function of duration between emergency room (ER) triage and operation (ER-OR) or admission and operation (Admit-OR) were analyzed by Student's t test, and regression analysis with P less than.05 considered significant.

RESULTS

Thirty-eight children (26%) were operated on within 6 hours of ER triage, whereas the remaining 88 children (74%) were operated on between 6 and 24 hours from ER triage. No significant difference was noted in perforation rate, LOS, costs, or operative time, nor were substantial changes in complications noted between those with an ER-OR < or =6 hours and greater than 6 hours. Likewise, no significant differences in these outcome measures were noted for Admit-OR greater than 6 when compared with < or =6 hours. Only costs with ER-OR greater than 12 hours and LOS with Admit-OR greater than 6 hours were significantly (without Bonferroni correction) different than < or = 6 hours. Multivariable linear regression analysis identified only LOS as a significant predictor of time to OR.

CONCLUSIONS

In children with acute appendicitis, delaying surgery until the daytime hours did not significantly affect operating time, perforation rate, or complications. Delayed management allows greater efficiency and effective use of physician and hospital resources, including decreased resident involvement in operations during the night.

Use of radiofrequency ablation of the lower esophageal sphincter to treat recurrent gastroesophageal reflux disease

PURPOSE

Recurrent gastroesophageal reflux disease (GERD) after gastroesophageal surgery is a troublesome problem. Reoperative surgery often is complicated by adhesions and recurrence. Radiofrequency ablation or energy delivery (RF or the Stretta procedure) is a new method for treating GERD. This study is the first report describing the use of the Stretta procedure in pediatric patients.

METHODS

Six patients who underwent previous gastroesophageal surgery presented with recurrent GERD. Medical records were reviewed and the severity of reflux graded using a modified scoring system. All underwent RF and were graded for GERD at 6 months postprocedure.

RESULTS

Mean operating time was 80 +/- 12 minutes. Mean age at initial operation was 12 +/- 4 years and for the RF, 18.0 +/- 3.4 years. All patients were discharged as outpatients. Early complications occurred in one child with self-resolving acute gastric distension. Five of 6 patients were completely asymptomatic at 3 months after the procedure, and 3 stopped anti secretory agents. One patient was improved but still symptomatic and needed a redo fundoplication. Another required a repeat application of RF 10 months after the initial one. Mean GERD score pre-Stretta was 5.2 +/- 1.0, which improved to 1.6 +/- 1.9 at 6 months postprocedure (P <.05; paired t test).

CONCLUSIONS

Use of RF treatment of the lower esophageal sphincter is a potentially successful modality to treat recurrent GERD in children. Long-term follow-up is required.

Effect of dietary fat on fat absorption and concomitant plasma and tissue fat composition in a rat model of short bowel syndrome

The aim of this study was to investigate the effect of dietary fat on the time course of changes in fat absorption and tissue and plasma lipid composition in a rat model of short bowel syndrome (SBS). Male Sprague-Dawley rats underwent either a bowel transection with re-anastomosis (Sham rats) or 75% small bowel resection (SBS rats). Animals were randomly assigned to one of three groups: Sham rats fed normal chow (Sham-NC), SBS rats fed normal chow (SBS-NC), or SBS rats fed a high-fat diet (SBS-HFD). Rats were sacrificed on day 3 or 14. Body weight, food intake, food clearance (dry fecal mass), and fat clearance (total fecal fat) were measured twice a week. Fat and energy intakes were calculated according to the amount of ingested food. Food and fat absorbability were calculated as intake minus clearance and were expressed as percent of intake. Serum cholesterol, triglyceride, and albumin were measured. Total lipid composition of the liver, epididymal adipose tissue, and the small intestine was determined. Statistical analysis was performed by a Student's test, with p values <0.05 considered significant. Both food and fat absorbability diminished after bowel resection in rats fed NC. This was accompanied by a decrease in body weight gain, plasma triglyceride and protein levels, and total lipid content of the liver at day 3 and of a decrease in adipose tissue at day 14 following operation. SBS-HFD rats experienced a significant increase (p<0.05) in food absorbability after 7 days and fat absorbability after 3 days compared with Sham-NC and SBS-NC rats (p<0.05), as well as increases in serum cholesterol, triglycerides, and glucose compared with SBS-NC rats. On day 14, plasma lipid levels in SBS-HFD rats were not different from SBS-NC or control rats; however, albumin levels were higher. A high-fat diet increased total fat content of the liver early after operation. In conclusion, in a rat model of SBS, an early high-fat diet increased the absorptive capacity of the intestinal remnant as seen by increased food and fat absorbability. These findings suggest a benefit of a high-fat diet on intestinal adaptation in general and on lipid absorption in particular.

The Kasai portoenterostomy for biliary atresia: A review of a 27-year experience with 81 patients

PURPOSE

The aim of this study was to utilize clinical outcome methodology through multivariable analysis of perioperative factors to predict a successful Kasai-portoenterostomy (PE).

METHODS

Records of 81 patients treated for biliary atresia (BA) were reviewed. Outcome was defined as successful if the patient was alive and had no liver transplant (LT). To predict future successful or failed PE, patients were categorized at 6 months post-PE into 2 groups: Success: direct bilirubin (DB) less than 2.0 mg/dL; Failure: DB greater than 2 mg/dL, or the patient was listed/had undergone LT, or had died. Groups were analyzed for positive or negative predictive values (PPV, NPV) at 2 and 5 years after PE. Cox regression was used to determine risk factors for PE.

RESULTS

PE was successful in 38% and failed in 62%. PPV of future success was 96% at 2 years post-PE and 95% at 5 years post-PE, NPV of failure was 76% and 74%, respectively. Bridging liver fibrosis at the time of PE and postoperative cholangitic episodes were interdependent risk factors for a failed PE (P <.05). Other covariates showed no significant relationship for PE outcome.

CONCLUSION

Classifying of patients 6 months postoperatively allowed us to determine a successful PE outcome. Bridging liver fibrosis at the time of the Kasai, and the increased number of postoperative cholangitic episodes were predictive of a poor PE outcome.

A new operative technique for restorative proctocolectomy: the endorectal pull-through combined with a double-stapled ileo-anal anastomosis

BACKGROUND

In children, restorative proctocolectomy is usually accomplished by a rectal mucosectomy followed by a hand-sewn ileo-anal anastomosis+/-ileal pouch. In certain patients, a hand-sewn anastomosis can be technically difficult. This led us to develop a new technique that combines endorectal mucosectomy with a double-stapled ileo-anal anastomosis.

METHODS

After colectomy, an ileal J-pouch is constructed. The head of the circular stapler is placed in the apex of the pouch and secured. An endorectal mucosectomy is completed from the abdomen to approximately 1.5 cm above the dentate line. The rectal mucosal/submucosal tube is everted onto the perineum. A transverse stapler is positioned 1.5 cm above the dentate line on the perineum and fired. The circular stapler is inserted transanally and the trocar advanced through the transverse staple line until the head and anvil are mated and then fired. A loop ileostomy is constructed.

RESULTS

Thirteen patients, with a mean age of 12.3 years, have undergone endorectal mucosectomy with a double-stapled anastomosis without major complication. The operative time averaged 280+/-70 minutes. The mean 24-hour stool frequency, with 9 months' follow-up, was 6.8+/-3.2, of which 1+/-0.7 were at night.

CONCLUSIONS

The combination of endorectal mucosectomy with a double-stapled anastomosis is a new approach for patients requiring restorative proctocolectomy. In our early experience, this technique was completed with a low complication rate and excellent functional results.

Low-fat diet impairs postresection intestinal adaptation in a rat model of short bowel syndrome

BACKGROUND

Low-fat diets (LFD) are utilized frequently in patients with short bowel syndrome (SBS). The purpose of this study was to investigate the effects of LFD on intestinal adaptation, enterocyte proliferation, and enterocyte cell death in a rat model of SBS.

METHODS

Adult male Sprague-Dawley rats were divided into 3 experimental groups: Sham-NC rats underwent bowel transection and reanastomosis and were fed normal chow (NC), SBS-NC rats underwent 75% small bowel resection and were fed NC, and SBS-rats were fed a low-fat diet (SBS-LFD). Parameters of intestinal adaptation, enterocyte proliferation, and enterocyte apoptosis were determined on day 14 after operation.

RESULTS

SBS-NC rats showed a significant increase (v Sham-NC) in jejunal and ileal bowel and mucosal weight, mucosal DNA and protein, villus height, and crypt depth. A significant 67% increase in crypt cell proliferation rate and 265% increase in villus enterocyte apoptosis was seen in the ileum of SBS-NC rats compared with control animals (P <.05). SBS-LFD animals showed lower ileal mucosal weight (29%; P <.05), jejunal crypt depth (20%; P <.05), and ileal villus height (21%; P <.05). A significant decrease in villus apoptosis in jejunum (74%; P <.05) and ileum (67%; P <.05) and a decrease in cell proliferation in ileum (35%; P <.05) was seen also after exposure to LFD compared with SBS-NC.

CONCLUSIONS

In a rat model of SBS, early LFD appears to inhibit parameters of intestinal adaptation. A possible mechanisms for this effect may be decreased cell proliferation. Decreased enterocyte loss via apoptosis, found in this study, may reflect a reduced number of enterocyte.

Interleukin-6 changes tight junction permeability and intracellular phospholipid content in a human enterocyte cell culture model

Proinflammatory cytokines and secretory phospholipase A(2) (sPLA(2)) are elevated in patients with inflammatory bowel disease (IBD). We previously reported that the proinflammatory cytokine IL-6 increased the expression of sPLA(2) (a hydrolyzer of phosphatidylcholine) and decreased membrane integrity in an intestinal epithelial cell culture model. To determine the physiological effects of the IL-6 mediated increase in sPLA(2) on decreased epithelial layer integrity, we investigated alterations of intracellular/secretory phospholipid (PL) composition in a cell culture model. In addition, since other PLs may also mediate epithelial membrane activity, we investigated the effect of IL-6 on PL activity in a Caco-2 enterocyte culture model. Caco-2 cells were incubated for 72 h with IL-6 or media alone (control). Both media and cell lysate were analyzed for PL composition using thin-layer chromatography. The PL composition in the media did not show any differences between the two groups ( p>0.1). Total intracellular PL contents were also unchanged; however, IL-6 led to significant changes in PL composition including an increase in phosphatidylethanolamine (PE) and sphingomyelin (SM) and a decrease in phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) ( p<0.05). Both PE and SM are known as inflammatory signaling factors involved in human IBD. Our study suggests that the decreased membrane integrity seen with IL-6 application may occur via intracellular PL alterations, rather than through the direct effects of sPLA(2).

[Medico-surgical consensus for management of children with gastroesophageal reflux Acapulco, Mexico 2002]

Gastroesophageal reflux (GER) is a common disease in children less one year old. It is present around 10% of unselected infant population. 40-50% have abnormal 24 h pH monitoring. An early diagnosis and treatment should be done in order to avoid complications.

AIM

To establish the consensus for the diagnosis and treatment of children with GER, to rule out similar diseases avoid the use of unnecessary drugs and the secondary side effects as well as unnecessary surgery.

METHOD

The consensus was done with the participation of general pediatricians, pediatrics gastroenterologist, pediatric surgeons, radiologist and endoscopist. An initial paper was done by pediatric surgeon and pediatric gastroenterologist who submitted to the rest of participants. Second stage: the paper was review through E-mail for all participants who send their suggestions and modifications. A new paper was done and discussed by medical and surgery area. During the Congress of Pediatric Surgery, in an open session was discuss again with the participation of the main authors and all the audience present. Finally, a paper was done and review for the main authors.

The effect of hypoxia on permeability and bacterial translocation in Caco-2 adult and I-407 fetal enterocyte cell culture models

Hypoxia has been implicated in the breakdown of the intestinal epithelial barrier in animals, leading to bacterial translocation (BT); however, the mechanism of this hypoxic insult is unknown. To determine the effects of hypoxic injury in vitro on epithelial membrane integrity, transepithelial electrical resistance (TEER), mannitol permeability (Ma-Pm), and BT were measured in both an adult (Caco-2) and fetal (I-407) intestinal epithelial cell culture model. Caco-2 adult and I-407 fetal epithelial cell monolayers were treated with or without bacteria (1 x 10(7) Escherichia coli. C-25), and then incubated under either normoxic (5% CO(2) in room air) or hypoxic (5% CO(2) and 95% N(2)) conditions at 37 degrees C for 6 h. Hypoxia caused a 10% increase in Ma-Pm in the I-407 fetal cell model independent of the bacterial challenge. In contrast, a bacterial challenge in the Caco-2 adult model caused a 485% increase in Ma-Pm independent of hypoxia. Neither hypoxia, nor C-25 bacteria, for 6 h caused BT in either cell culture model. In the adult cell culture model, bacteria appear to mediate changes in epithelial barrier function, with hypoxia having no effect. On the other hand, hypoxia is the major factor in the loss of epithelial barrier function in fetal epithelium, but has no effect on adult epithelium. The data suggest that the breakdown of barrier function caused by a hypoxic insult is the primary stimulus for subsequent BT in neonates.

Effects of enteral arginine supplementation on the structural intestinal adaptation in a rat model of short bowel syndrome

The nitric oxide precursor L-arginine (ARG) has been shown to influence intestinal morphology and intestinal absorptive function. The purpose of the present study was to determine the effect of enteral ARG supplementation on structural intestinal adaptation, cell proliferation, and apoptosis in a rat model of short bowel syndrome (SBS). Thirty male Sprague-Dawley rats were divided into three experimental groups: Sham rats underwent bowel transection, SBS rats underwent 75% small bowel resection, and SBS-ARG rats underwent bowel resection and were treated with ARG given in the drinking water (2%). Parameters of intestinal adaptation, enterocyte proliferation and enterocyte apoptosis were determined on day 14 following operation. We have demonstrated that SBS-ARG animals had a lower jejunal and ileal mucosal weight, jejunal mucosal DNA and protein, ileal mucosal protein, jejunal villus height, jejunal and ileal crypt depth, and enterocyte proliferation index and a greater enterocyte apoptosis compared to SBS untreated animals. We conclude that in a rat model of SBS enteral L-arginine inhibits structural intestinal adaptation. Possible mechanism for this effect may be decreased cell proliferation and increased cell apoptosis.

Gene alteration of intestinal intraepithelial lymphocytes in response to massive small bowel resection

BACKGROUND

The intestinal adaptive response [increased epithelial cell (EC) proliferation and apoptosis] after massive small bowel resection (SBR) is partially controlled by intraepithelial lymphocytes (IEL). To identify IEL factors contributing to EC adaptation post-SBR we utilized microarray assays.

METHODS

Mice underwent a 70% SBR (SBR1w/SBR4w) or sham operation (Sham1w/Sham4w). After 1 or 4 weeks (1w, 4w) small bowel was harvested, and IEL isolated. Determination of the EC-proliferation rate used BrdU incorporation, and of the EC-apoptotic rate used Annexin V staining. Affymetrix system microarrays (12,491 genes) were performed to examine IEL-mRNA expression. Results were considered significant if fold-change (FC) between groups was >2 and P<0.05 (F-test), or FC>3 and 0.05> P >0.01, or FC>4 and P>0.05. Significant genes were confirmed by conventional RT-PCR.

RESULTS

The SBR EC-proliferation rate increased significantly in both 1w and 4w groups compared to Sham: SBR1w 0.24+/-0.07 vs. Sham1w 0.12+/-0.02 (P=0.03); SBR4w 0.35+/-0.04 vs. Sham4w 0.19+/-0.02 ( P<0.01). The EC-apoptotic rate was unchanged in the 1w group, but significantly differed from controls after 4 weeks: SBR4w 39.92+/-6.78 vs. Sham4w 12.56+/-6.44 ( P<0.01). Microarray results were analyzed to identify potential growth-modifying IEL genes. The following were identified (function in parenthesis; A, apoptosis; P, proliferation): lipocalin 2 (promotes A), angiotensin converting enzyme (increases A), Rap2 interacting protein (reduces A, promotes P), amphiregulin (promotes P) and leucine-rich-alpha2-glycoprotein (promotes A, reduces P). Based on RT-PCR results these genes showed significant changes between groups. The increase in ACE at 1w preceded the observed apoptotic changes. The alterations in lipocalin 2, Rap2 and amphiregulin at 4w coincided with the marked changes in growth and apoptosis in the SBR mice.

CONCLUSIONS

IEL undergo temporal changes after SBR. These findings provide profound insight into potential IEL-dependent regulation of EC homeostasis post-SBR.

Effect of a high fat diet on lipid absorption and fatty acid transport in a rat model of short bowel syndrome

Long chain fatty acids (LCFAs) appear to be powerful stimulants for small bowel adaptation in patients with short bowel syndrome (SBS). However, the dietary lipid content may alter intestinal lipid transport. The aim of this study was to investigate the effects of a high fat diet (HFD) on in vivo lipid absorption and molecular and cellular mechanisms of LCFAs uptake by the remaining bowel. Male Sprague-Dawley rats (240-280) were randomly assigned to one of three groups: sham rats fed normal chow (sham-NC), SBS rats fed NC (SBS-NC) and SBS rats fed HFD (SBS-HFD). SBS rats underwent a 75% small bowel resection. Rats were sacrificed on day 3 or 14. Body weight, fat intake and fat clearance (total fecal fat) were measured twice a week. Fat absorbability was calculated as intake minus clearance and was expressed as percent of intake. Total RNA from the mucosa of duodenum, jejunum and ileum was extracted using TRIZOL Reagent. Northern blot analysis was performed to determine FAT/CD36 mRNA levels. Enterocyte LCFA transport was measured on day 14. LCFA uptake was determined by measuring cellular [3H]-oleate uptake over time (4-120 s). Mean (+/-SE) FAT/CD36 mRNA levels and oleate uptake kinetic parameters were analyzed using ANOVA. Fat absorbability diminished after bowel resection, suggesting fat malabsorption. Remaining bowel in SBS-NC rats responded by an increase in FAT/CD36 mRNA levels in the duodenum and ileum on day 3, and the duodenum and jejunum on day 14 compared to sham-NC animals, and was accompanied by an increase in enterocyte LCFA transport in all segments. Exposure to a HFD for 14 days resulted in significantly increased fat absorbability after 3 days compared to SBS-NC rats. However, FAT/CD36 mRNA levels (vs. SBS-NC) decreased in all segments on day 3. On day 14, FAT/CD36 mRNA levels were decreased in the duodenum and ileum and were accompanied by reduced oleate uptake by isolated enterocytes in the ileum (vs. SBS-NC). In a rat model of SBS, early high fat diet increased lipid absorptive capacity of the intestinal remnant as seen by increased fat absorbability. The main mechanisms of this effect may be an acceleration of structural intestinal adaptation resulting in an increased number of enterocytes. However, at molecular and cellular levels HFD decreased mucosal FAT/CD36 mRNA levels and oleic acid uptake by isolated enterocytes.

Primary pull-through for Hirschsprung’s disease

The first report of a successful primary pull-through for Hirschsprung's disease using the endorectal pull-through (ERPT) was by So et al. (J. Pediatr. Surg. 15 (1980) 470; J. Pediatr. Surg. 33 (1998) 673). Subsequently, because of the simplified nature of this approach and the potential for cost savings, several groups have reported excellent results with this procedure. In addition to the ERPT, both the Duhamel and Swenson procedures have been performed in a one-stage fashion. More recently, primary laparoscopic approaches for each of these techniques have been utilized. The purpose of this review is to discuss the technique of primary pull-through, the peri-operative management and a summary of clinical results.

Increased respiratory symptoms following surgery in children exposed to environmental tobacco smoke

OBJECTIVE

The aim of this study was to determine if children exposed to environmental tobacco smoke (ETS) via parental smoking (ETS+) developed more respiratory symptoms resulting in longer recovery times following surgical outpatient procedures compared with children of nonsmoking parents (ETS-).

METHODS

One hundred and forty six children (4.9 +/- 3 years) undergoing inguinal hernia repair were prospectively studied. Parental smoking behaviour was determined by survey and urine analysis. Seven respiratory symptoms were evaluated during induction and emergence from anaesthesia and during the recovery room (RR) stay.

RESULTS

Fifty-seven (39%) families admitted a smoking history while 89 (61%) denied it. This strongly correlated with the cotinine/creatinine ratio (Pearson correlation coefficient = 0.76; P = 0.01). ETS exposure was associated with an increased frequency of RR symptoms (ETS+: 56%; ETS-: 31%; P = 0.007).

CONCLUSIONS

In children undergoing general anaesthesia for inguinal hernia repair, ETS exposure was associated with an increased frequency of respiratory symptoms during emergence from anaesthesia and during postoperative recovery.

Reoperative surgery for Hirschsprung's disease

Most patients who undergo a pull-through procedure for Hirschsprung's disease typically do well. A small number of patients have persistent stooling problems, often manifesting with either constipation or recurrent enterocolitis. A group of these patients will not respond to conservative medical management and may need to undergo another operative procedure. Reoperative surgery for Hirschsprung's disease typically falls into 2 categories, those who require a myectomy and those who need a redo pull-through. This article reviews the workup, indications, and techniques for these procedures and discusses previously published, as well as the authors' outcome, with these 2 procedures.