A Practical Predictive Index for Intra-abdominal Septic Complications After Primary Anastomosis for Crohn's Disease: Change in C-Reactive Protein Level Before Surgery.

BACKGROUND: Postoperative intra-abdominal septic complications are difficult to manage in Crohn's disease, which makes prevention especially important. OBJECTIVE: The purpose of this study was to examine the risk factors for intra-abdominal septic complications after primary anastomosis for Crohn's disease and to seek a practical predictive index for intra-abdominal septic complications. DESIGN: This was a retrospective study. SETTINGS: The study was conducted in a tertiary referral hospital. PATIENTS: Based on a computerized database of 344 patients with Crohn's disease who underwent primary anastomosis between 2004 and 2013, the patients were placed into an intra-abdominal septic complications group and a group without intra-abdominal septic complications. MAIN OUTCOME MEASURES: Univariate and multivariate analyses were performed to identify risk factors, and the predictive accuracy of possible predictors was assessed using receiver operating characteristic curves. RESULTS: Overall, 39 patients (11.34%) developed intra-abdominal septic complications. Preoperative C-reactive protein level >10 mg/L was found to be an independent risk factor (p < 0.01) for intra-abdominal septic complications. For prediction of intra-abdominal septic complications, receiver operating characteristic curve analysis showed that a C-reactive protein cutoff of 14.50 mg/L provided negative and positive predictive values of 96.84% and 34.07%. In addition, the change in C-reactive protein levels over the 2 weeks before surgery was greater in the intra-abdominal septic complications group than the group with no intra-abdominal septic complications (p < 0.01), and the directions of change were opposite, upward in the former and downward in the latter. Apart from being a risk factor for intra-abdominal septic complications (p < 0.01), receiver operating characteristic curve analysis showed that the change in C-reactive protein levels before surgery had a negative predictive value for intra-abdominal septic complications of 98.66% and a positive predictive value of 76.09%. LIMITATIONS: This was a retrospective study. CONCLUSIONS: Changes in C-reactive protein before surgical treatment of Crohn's disease could serve as a practical predictive index for postoperative intra-abdominal septic complications.

Interleukin-13 and transforming growth factor ß synergise in the pathogenesis of human intestinal fistulae.

OBJECTIVE: Epithelial to mesenchymal transition (EMT) seems to play an important role in the pathogenesis of fistulae, a common clinical complication of Crohn's disease (CD). TGFß and interleukin-13 (IL-13) have been correlated with the onset of EMT-associated organ fibrosis and high levels of TGFß have been shown in transitional cells (TCs) lining CD fistula tracts. This study investigated whether IL-13 could be involved in the pathogenesis of CD-associated fistulae. DESIGN: Protein or mRNA levels in HT29 intestinal epithelial cells (IECs) or colonic lamina propria fibroblasts (CLPFs) were studied by western blotting or real-time PCR. CLPFs were isolated from non-inflammatory disease controls or patients with CD with or without fistulae and IL-13 levels were analysed in surgically removed fistula specimens by immunohistochemistry. RESULTS: TGFß induced IL-13 secretion in CLPFs from patients with fistulising CD. In fistula specimens high levels of IL-13 were detected in TCs covering fistula tracts. In HT29 IEC monolayers, IL-13 induced SLUG and ß6-integrin mRNA, which are associated with cell invasion. HT29 spheroids completely disintegrated when treated with TGFß for 7 days, whereas IL-13-treated spheroids did not show morphological changes. Here, TGFß induced mRNA expression of SNAIL1 and IL-13, whereas IL-13 elevated SLUG and ß6-integrin mRNA. An anti-IL-13 antibody was able to prevent IL-13-induced SLUG expression in HT29 IECs. CONCLUSIONS: TGFß induces IL-13 expression and an EMT-like phenotype of IECs, while IL-13 promotes the expression of genes associated with cell invasion. These findings suggest that TGFß and IL-13 play a synergistic role in the pathogenesis of fistulae and inhibition of IL-13 might represent a novel therapeutic approach for fistula treatment.

Lymphatic diamine oxidase secretion stimulated by fat absorption is linked with histamine release.

Diamine oxidase (DAO) is abundantly expressed in mammalian small intestine catalyzing the oxidative breakdown of polyamines and histamine. The aim of this study was to determine the relationship between stimulation of intestinal diamine oxidase secretion with intestinal fat absorption and histamine release. Conscious intestinal lymph fistula rats were used. The mesenteric lymph ducts were cannulated and intraduodenal tubes were installed for the infusion of Liposyn II 20% (an intralipid emulsion). Lymphatic DAO activity and protein secretion were analyzed by radiometric assay and Western blot, respectively. Lymphatic histamine concentration was measured by ELISA. Infusion of Liposyn II (4.43 kcal/3 ml) resulted in a ~3.5-fold increase in lymphatic DAO protein secretion and DAO activity, peaking at 1 h and lasting for 3 h. Liposyn II infusion also increased the lymphatic histamine release, a substrate for DAO. To determine the relationship of DAO release with histamine release, histamine was administered intraperitoneally (10 mg/kg) in fasting rats and resulted in a significant doubling in lymphatic DAO activity, supporting a link between histamine and DAO. In addition, ip administration of the histamine H4 receptor antagonist JNJ7777120 significantly reduced the Liposyn II-induced DAO output by 65.9%, whereas H(1) (pyrilamine maleate), H(2) (ranitidine), and H(3) (thioperamide maleate) receptor antagonists had little effect. We conclude that DAO secretion may contribute to the catabolism of histamine released during fat absorption and this is probably mediated through the histamine H(4) receptor.

Metabolic and nutritional support of the enterocutaneous fistula patient: a three-phase approach.

BACKGROUND: The care and outcome of enterocutaneous fistula (ECF) have improved greatly over several decades due to revolutionary advances in nutrition, along with dramatic improvements in the treatment of sepsis and the critically ill. However, as the collective experience with damage control surgery has matured, the frequent development of enteroatmospheric fistula (EAF) in the "open abdomen" patient has emerged as an even more vexing problem. Despite our best efforts, ECF and especially EAF continue to be highly morbid conditions, and sepsis and malnutrition remain the leading causes of death. Aggressive nutritional and metabolic support is the most significant predictor of outcome with ECF and EAF. RESULTS: Discussion of the historical advances in nutritional therapy and their impact on ECF, as well as review of the classification of ECF and EAF, provides a framework for the suggested phased strategy that specifically targets the nutritional and metabolic needs of the ECF/EAF patient. These three phases include (1) diagnosis, resuscitation, and early interval nutrition; (2) definition of fistula anatomy, drainage of collections, nutritional assessment and monitoring, and placement of feeding access; and (3) definitive nutritional management, including pharmacologic adjuncts. Early nutritional support with parenteral nutrition followed by transition to enteral nutrition is advocated, including the merits of delivery of enteral nutrition via the fistula itself, known as fistuloclysis. CONCLUSION: Aggressive nutritional therapy is necessary to reverse the catabolic state associated with ECF/EAF patients. Once established, it allows proper time, preparation, and planning for definitive management of the fistula, and in many cases provides the support for spontaneous closure.

Prospective study of immunological factors in non-inflammatory bowel disease enterocutaneous fistulas.

BACKGROUND: Enterocutaneous fistulas (ECF) are debilitating and usually result following complex abdominal surgery. While there is an association with inflammatory bowel disease (IBD), a large number of fistulas occur after surgery not related to IBD. The consequences of ECF include short bowel syndrome and the need for long term parenteral nutrition.ECF can heal spontaneously and in the case of IBD can be cured by medical therapy in some instances. Those that do not resolve spontaneously have to be cured by surgery which is complex and associated with a high morbidity. It is not considered traditional treatment to use the same medical therapy as in IBD to cure ECF caused by other conditions.A small case series has reported three patients with persistent ECF not related to IBD to have healed following use of Infliximab which is the treatment commonly used for ECF caused by IBD. Infliximab acts by inhibiting the activity of the inflammatory cytokine TNF- alpha. It is not known if this cytokine is present in ECF tissue in the absence of IBD.The aim of this study is to demonstrate the presence of inflammatory markers in tissue surrounding non-IBD ECF and in particular to quantify the presence of the cytokine TNF- alpha. We hypothesise that TNF - alpha levels are raised in non-IBD ECF. METHODS/DESIGN: Tissue and serum from ECF of IBD and non-IBD patients will be prospectively collected at St. Mark's Hospital Intestinal Failure Unit. The control group will consist of patients undergoing colonoscopy for bowel cancer screening, with normal findings. Biopsies of the terminal ileum will be obtained from this group during colonoscopy. The fistula tract and serum cytokine profiles of interleukins (IL)-1a, IL-1b, IL-2, IL-4, IL-6, IL-8, IL-10, TNF- alpha, IFN-y, MCP-1, EGF and VEGF will be assessed. DISCUSSION: This study aims to assess the presence or absence of TNF- alpha expression in the ECF tissue in non-IBD origin. If our hypothesis is correct we would then be able to study the use of the TNF- alpha inhibitor Infliximab as a therapeutic option in the treatment of non-IBD ECF. Secondary aims include assessing the spectrum of inflammatory cytokines and markers present in tissue and serum of non-IBD ECF when compared with IBD ECF and normal controls. TRIAL REGISTRATION: ISRCTN44000447.

Transplantation of Human Intestine Into the Mouse: A Novel Platform for Study of Inflammatory Enterocutaneous Fistulas.

BACKGROUND AND AIMS: Enteric fistulas represent a severe and medically challenging comorbidity commonly affecting Crohn's disease [CD] patients. Gut fistulas do not develop in animal models of the disease. We have used transplantation of the human fetal gut into mice as a novel platform for studying inflammatory enterocutaneous fistulas. METHODS: Human fetal gut segments were transplanted subcutaneously into mature SCID mice, where they grew and fully developed over the course of several months. We first analysed the resident immune cells and inflammatory response elicited by systemic lipopolysaccharide [LPS] in normal, fully developed human gut xenografts. Thereafter, we used immunostaining to analyse fully developed xenografts that spontaneously developed enterocutaneous fistulas. RESULTS: Resident human innate and adaptive immune cells were demonstrated in gut xenografts during steady state and inflammation. The expression of human IL-8, IL-1ß, IL-6, TNF-α, A20, and IkBα was significantly elevated in response to LPS, with no change in IL-10 gene expression. Approximately 17% [19/110] of fully developed subcutaneous human gut xenografts spontaneously developed enterocutaneous fistulas, revealing striking histopathological similarities with CD fistula specimens. Immunohistochemical analyses of fistulating xenografts revealed transmural lymphocytic enteritis associated with massive expansion of resident human CD4+ lymphocytes and their migration into the intraepithelial compartment. Regionally, mucosal epithelial cells assumed spindle-shaped mesenchymal morphology and formed fistulous tracts towards chronic non-healing wounds in the host mouse skin overlying the transplants. CONCLUSIONS: Inflammation and fistulas developed in human gut xenografts lacking IL-10 gene response. This novel model system will enable systematic studies of the inflamed and fistulating human gut in live animals.

Effects of recombinant human growth hormone on enterocutaneous fistula patients.

AIM: To explore the effects of recombinant human growth hormone (rhGH) on intestinal mucosal epithelial cell proliferation and nutritional status in patients with enterocutaneous fistula. METHODS: Eight patients with enterocutaneous fistulas received recombinant human growth hormone (10 microg/d) for 7 d. Image analysis and immunohistochemical techniques were used to analyse the expression of proliferating cell nuclear antigen (PCNA) in intestinal mucosal epithelial cells in biopsy samples from the patients who had undergone an endoscopic biopsy through the fistula at day 0, 4 and 7. Body weights, nitrogen excretion, serum levels of total proteins, albumin, prealbumin, transferrin and fibronectin were measured at day 0, 4 and 7. RESULTS: Significant improvements occurred in the expression of PCNA in the intestinal mucosal epithelial cells at day 4 and 7 compared to day 0 (24.93 +/- 3.41%, 30.46 +/- 5.24% vs 12.92 +/- 4.20%, P < 0.01). These changes were accompanied by the significant improvement of villus height (500.54 +/- 53.79 microm, 459.03 +/- 88.98 microm vs 210.94 +/- 49.16 microm, P < 0.01), serum levels of total proteins (70.52 +/- 5.13 g/L, 74.89 +/- 5.16 g/L vs 63.51 +/- 2.47 g/L, P < 0.01), albumin (39.44 +/- 1.18 g/L, 42.39 +/- 1.68 g/L vs 35.74 +/- 1.75 g/L, P < 0.01) and fibronectin (236.3 +/- 16.5 mg/L, 275.8 +/- 16.9 mg/L vs 172.5 +/- 21.4 mg/L, P < 0.01) at day 4 and 7, and prealbumin (286.38 +/- 65.61 mg/L vs 180.88 +/- 48.28 mg/L, P < 0.05), transferrin (2.61 +/- 0.12 g/L vs 2.41 +/- 0.14 g/L, P < 0.05) at day 7. Nitrogen excretion was significantly decreased at day 7 (3.40 +/- 1.65 g/d vs 7.25 +/- 3.92 g/d, P < 0.05). No change was observed in the body weight. CONCLUSION: Recombinant human growth hormone could promote intestinal mucosal epithelial cell proliferation and protein synthesis in patients with enterocutaneous fistula.

Metabolism and recycling of urea in man.

The rate of breakdown and reutilization of urea in man has been measured in five normal and two septic patients using 15N and 13C labeled ureas. The labeled molecules of the 15N urea dose were distinguished from the labeled molecules of the recycled urea by analyzing in a mass spectrometer the isotopic nitrogens produced when the recrystalized urine urea was treated with a hypobromite solution. In a normal subject with regular nitrogen intake, it was found that only 4/5 of the produced urea was excreted in urine and the rest was endogenously degraded. Seventy percent of the nitrogen and 63% of the carbon of the degraded urea were returned to the urea pool. On a nitrogen-free diet or after neomycin treatment with regular diet in the normal, the extent of urea splitting is considerably reduced. In the septic patients, breakdown, as well as recycling of urea was almost eliminated. It appears that the reate of endogenous catabolism of urea depends mainly on the activity of the gut flora which may be affected by dietary intake and clinical status of the subject. The method developed here could be applied for the quantitation of urea dynamics under different physiological and pathological conditions.

Parenteral nutrition in the septic patient: nitrogen balance, limiting plasma amino acids, and calorie to nitrogen ratios.

A series of eight septic patients was provided varying levels of beef fibrin protein hydrolysate by central vein in the presence of adequate calories for evaluation of nitrogen retention under septic conditions. The mean nitrogen intake to achieve nitrogen equilibrium was 240 mg/kg of body wt per day. This represents a 40% increase over that required to produce nitrogen equilibrium in normal adults. The mean caloric intake of these patients was 43.3 kcal/kg of body wt per day. The calorie to nitrogen ratio based on the above intake was calculated to be 180:1. In order to utilize effectively calorie to nitrogen ratios in the nutritional care of patients, it is suggested that ratios be standardized using daily total coloric expenditures. Correcting the mean measured resting calorie expenditures of these patients for minimal daily activity, a caloric to nitrogen ratio of 138:1 was obtained. The plasma amino acid ratios in these septic patients confirm the finding that valine and phenylalnine are limiting amino acids in a beef fibrin hydrolysate at infusion levels below 240 mg of N/kg of body wt per day. Analysis of the urinary excretion of total nitrogen, urea, and amino acids in two patients suggests that 30 to 50% of the infused peptides of a beef fibrin hydrolysate are lost in the urine in these septic patients.