Bacterial translocation: the influence of dietary variables

A Cross-sectional Survey to Review Food Safety Practices Within Pediatric Oncology and Stem Cell Transplant Centers in the United Kingdom

FOOD SAFETY AND PEDIATRIC CANCER

Neutropenia is a common complication of chemotherapy, which poses a high risk of infection and mortality. Neutropenic diet has historically been recommended for those undergoing chemotherapy. The rationale is to reduce the risk of foodborne infection by avoiding foods considered to be of high microbial risk. However, evidence for this diet is limited, and there is a lack of national consensus guidelines.

AIM

Ascertain food safety advice across specialist centers providing high-dose chemotherapy for malignancy or stem cell transplants in the United Kingdom.

MATERIALS AND METHODS

Dietitians at 22 centers were contacted to complete a questionnaire regarding food safety guidance implemented at their center for pediatric patients undergoing high-dose chemotherapy or stem cell transplants. Questions related to restricted foods, specific guidelines implemented, ward food provision, and timings of food provision.

RESULTS

Sixteen centers responded (73%). Many aspects of neutropenic diet were consistent across centers; avoidance of unpasteurized dairy products (94%), raw/undercooked meat (94%), and unpasteurized pâté (88%). There was a lack of consistency regarding water sources used on wards and unpeeled fruits and vegetables.

CONCLUSIONS

Food safety guidance for neutropenic patients differs across centers, with some practices seeming outdated and nonevidence based. A national review of food safety guidance should be considered to provide a standardized approach.

Listeriosis Risk Model for Cancer Patients Who Consume Ready-to-Eat Salad

The foodborne pathogen Listeria monocytogenes generally infects immunocompromised individuals, such as cancer patients, more frequently and with higher morbidity and mortality than the general population. Because of the anticipated risk associated with L. monocytogenes and other pathogens in produce, immunocompromised individuals are often placed on neutropenic diets that exclude fresh produce, though these risks have not been quantified. Therefore, this study developed a data-driven risk model for listeriosis in cancer patients who consume ready-to-eat (RTE) salads, consisting of leafy greens, cucumbers, and tomatoes, as influenced by kitchen-scale treatments and storage practices. Monte Carlo simulations were used to model the risk of invasive listeriosis during one chemotherapy cycle. Refrigerating all salad components decreased median risk by approximately one-half log. For refrigerated salads with no treatment, the predicted median risk was ≤ 4.3 × 10^-08. When salad ingredients were surface blanched with greens rinsed, the predicted risk decreased to 5.4 × 10^-10. Predicted risk was lowest (1.4 × 10^-13) for a blanched "salad" consisting of solely cucumbers and tomatoes. Interestingly, rinsing, as recommended by FDA only decreased median risk by 1 log. A sensitivity analysis revealed that the highly variable dose-response parameter k strongly influenced risk, indicating that reducing uncertainty in this variable may improve model accuracy. Overall, this study demonstrates that kitchen-scale pathogen reduction approaches have high risk-reduction efficacy and could be considered as an alternative to diets that exclude produce when making risk management decisions.

Interrelationship between endotoxicosis and syndrome of intraabdominal hypertension in pathogenesis of abdominal sepsis

Objective. Studying of mutual role of the main pathogenetic factors of abdominal sepsis – the inflammation origin and intraabdominal hypertension, from the one side, endotoxicosis and the abdominal compression syndrome (ACS), from the other side. Materials and methods. Into the investigation 196 patients with abdominal sepsis were included, in whom after the certain preliminary preparation the operative procedure was done. The levels of neutrophils, macrophages, interleukin–6, interleukin–10 in peritoneal exudate were studied as indices of the inflammation source for abdominal cavity. These indices were characteristic for systemic answer on general reaction, the degree of which have determined the abdominal sepsis course and result. Determination of intraabdominal pressure was applied for estimation the intraabdominal hypertension role in abdominal sepsis. Results. The ratio of the endotoxicosis and the ACS indices in the complications structure, not dependent on some differences due to the complication type present, was practically similar. Conclusion. The results of the investigation conducted, witnesses the presence of interrelationship of roles of endotoxicosis and the abdominal compression syndrome in pathogenesis of abdominal sepsis, their indices changes are characterized by mutual activity strengthening, accompanied by clinical manifestations of the organs dysfunction, determining the severity of course and result of pathological process in the organism.

Gut barrier disruption and chronic disease

The intestinal barrier protects the host against gut microbes, food antigens, and toxins present in the gastrointestinal tract. However, gut barrier integrity can be affected by intrinsic and extrinsic factors, including genetic predisposition, the Western diet, antibiotics, alcohol, circadian rhythm disruption, psychological stress, and aging. Chronic disruption of the gut barrier can lead to translocation of microbial components into the body, producing systemic, low-grade inflammation. While the association between gut barrier integrity and inflammation in intestinal diseases is well established, we review here recent studies indicating that the gut barrier and microbiota dysbiosis may contribute to the development of metabolic, autoimmune, and aging-related disorders. Emerging interventions to improve gut barrier integrity and microbiota composition are also described.

Severe Gastrointestinal Involvement in Pediatric Stevens-Johnson Syndrome: A Case Report and Review of the Literature

Stevens-Johnson syndrome and toxic epidermal necrolysis form a rare but severe disease spectrum characterized by widespread epidermal detachment. Gastrointestinal manifestations of the disease, however, are rarely described in the pediatric literature and have a high mortality among adults. There are limited data on the treatment of these cases, with conflicting evidence regarding the benefit of steroids, IVIG, or other immunosuppressive agents. We review previous instances of gastrointestinal involvement in children and report the case of a previously healthy 13-year-old who presented with the typical ocular and skin findings of Stevens-Johnson syndrome, subsequently developed severe life-threatening diarrhea, and was found to have severe esophagitis, duodenitis, and colitis on endoscopic evaluation. Treatment was initiated with an immediate, short course of steroids along with early introduction of an enteral diet via nasogastric tube, and resulted in full gastrointestinal recovery. This case highlights successful medical treatment of the first reported pediatric case of SJS/TEN with both upper and lower gastrointestinal tract involvement.

Simplified percutaneous endoscopic transgastric conduit feeding jejunostomy for dysphagia after esophagectomy

Unexpected dysphagia is an important problem affecting life prognosis in patients who have undergone an esophagectomy for esophageal cancer. For nutritional support in patients suffering from dysphagia after a previous esophagectomy, a simplified percutaneous endoscopic transgastric conduit feeding jejunostomy approach was developed that can be performed regardless of the patient's condition. The feasibility of this procedure in 25 patients with esophageal cancer who underwent three-stage esophagectomy with retrosternal gastric conduit reconstruction from April 2009 to December 2016 was evaluated retrospectively. Under fluoroscopy, a percutaneous endoscopic transgastric conduit feeding jejunostomy catheter (9 French) was introduced into the jejunum in the epigastric region using the Seldinger's technique. The following patient data were analyzed retrospectively: operating time, complications, reasons for oral intake difficulty, and clinical data describing patients' nutritional status before and 1 month after percutaneous endoscopic transgastric conduit jejunostomy treatment, such as serum albumin and clinical course. Median patients' age was 68 years (range 50-76 years). Indications for the procedure were late swallowing dysfunction (n = 12), early swallowing dysfunction secondary to surgical complication (n = 8), anastomotic leakage (n = 3), and anorexia (n = 2). Causes of late swallowing dysfunction were radiation injury (n = 8), advanced age (n = 2), or cerebral infarction (n = 2). The median operating time was 29 minutes (range 14-82 minutes). Four patients developed mild erosions at the stoma secondary to bile reflux along the side of the catheter. No patient experienced severe complications such as ileus and peritonitis. Patients were treated for a median of 160 days (range 18-3106 days) with percutaneous endoscopic transgastric conduit jejunostomy. Patient's serum albumin significantly increased from 2.8 to 3.3 g/dl in 1 month. Of the eight patients with early swallowing dysfunction, six successfully regained sufficient oral nutrition after receiving enteral feeding nutritional management. Although all except one late swallowing dysfunction patient could not discontinue tube feeding, five patients were long-term survivors at the time this report was written. This jejunostomy procedure is simple, safe, and useful for patients with unexpected dysphagia and accompanying malnutrition after esophagectomy.

Infection rate among nutritional therapies for acute pancreatitis: A systematic review with network meta-analysis of randomized controlled trials

Background

Infection in acute pancreatitis (AP) is associated with nutritional therapies including naso-gastric (NG), naso-jejunal (NJ), and total parenteral nutrition (TPN). To examine infections among NG, NJ, TPN, and no nutritional support (NNS) in treating patients with AP.

Methods

The investigators completed comprehensive search in the Cochrane library, EMBASE, PubMed, Web of Science, and ClinicalTrials.gov without restriction on language and publication date before January 21, 2019. They also searched the reference lists of relevant studies for randomized controlled trials (RCTs) comparing NG, NJ, TPN, and NNS among patients with AP. Quantitative synthesis was conducted in a contrast-based network meta-analysis. To clarify effects, a network meta-analysis was conducted to calculate the surface under the cumulative ranking curve (SUCRA). Beside of overall infections, the event rates of infected pancreatic necrosis, bacteremia, line infection, pneumonia, urinary tract infection, and other types of infections were measured.

Results

The network meta-analysis of 16 RCTs showed that NJ had significantly lower overall infection rates compared with TPN (risk ratio: 0.59; 95% confidence interval: 0.38, 0.90); and NG had a larger effect size and higher rank probability compared with NJ, TPN, and NNS (mean rank = 1.7; SUCRA = 75.8). TPN was the least preferred (mean rank = 3.2; SUCRA = 26.6).

Conclusions

NG and NJ may be preferred therapies for treating patients with AP. Clinicians may consider NG as a first-line treatment for patients with AP (including severe AP) and even in patients receiving prophylactic antibiotics. In addition, we found that NNS should be avoided when treating patients with severe AP.

Hyperbilirubinemia predicts the infectious complications after esophagectomy for esophageal cancer

Background

Surgical stress and inflammation can cause hyperbilirubinemia, which sometimes occurs after esophagectomy for esophageal cancer (EC). The aim of this study was to elucidate the clinical significance of postoperative hyperbilirubinemia in the management of EC patients.

Materials and methods

We retrospectively reviewed records of 81 EC patients who underwent esophagectomy from 2009 to 2014. We compared the clinicopathological and perioperative factors, including the presence of hyperbilirubinemia (total bilirubin ≥1.5 mg/dL), between patients with postoperative infectious complications (PIC group) and those without (Non-PIC group).

Results

PIC developed in 52 patients (64.2%). There were significant differences in incidence of postoperative hyperbilirubinemia between the PIC group and the non-PIC group (34.6% vs. 3.4%, P = 0.002), as well as the approach of esophagectomy (P = 0.045), the surgical duration (469 vs. 389 min, P < 0.001), the amount of blood loss (420 vs. 300 mL, P = 0.018), the frequency of intraoperative blood transfusions (32.7% vs. 6.9%, P = 0.012) and the peak postoperative C-reactive protein level (17.3 vs. 8.6 mg/dL, P = 0.007). Multivariate analysis revealed hyperbilirubinemia was independently associated with the occurrence of PICs (odds ratio: 38.6, P = 0.010). The median time to the diagnosis of hyperbilirubinemia was significantly shorter than that of PICs (3.0 vs. 4.5 days, P = 0.025).

Conclusions

Postoperative hyperbilirubinemia was associated with the occurrence of PICs and frequently occurred before any PICs become apparent. More attention should be paid to the serum bilirubin level in the management after esophagectomy for EC.

Effects of Prenatal Consumption of Caprine Milk Oligosaccharides on Mice Mono-associated with Bifidobacterium Bifidum (AGR2166)

BACKGROUND

Prenatal consumption of oligosaccharides are associated with changes in the maternal gastrointestinal tract (GIT) microbiota with health consequences for the offspring. It has previously been demonstrated that caprine milk oligosaccharides (CMO) stimulate the growth and fermentation rate of Bifidobacterium bifidum AGR2166.

OBJECTIVE

The objective of this study was to examine the effects of B. bifidum AGR2166 and prenatal consumption of CMO, alone or in combination, on the dam's large intestine, foetal development and ability of B. bifidum to translocate from the gastrointestinal lumen to organs and foetal membranes.

METHOD

Germ-free BALB/c mice, inoculated with B. bifidum AGR2166 or anaerobic phosphate buffer, were fed either diet supplemented with CMO or with galacto-oligosaccharide. Pregnant mice were euthanised 1 to 3 days before the expected delivery date and samples collected for analysis.

RESULTS

Dietary CMO, regardless of bifidobacterial inoculation was shown to increase GIT weight and to reduce foetal weight compared to galacto-oligosaccharide-fed dams. B. bifidum AGR2166 DNA was detected in the mesenteric lymph nodes, liver, plasma and placenta of the dam by amplification of the bifidobacterial 16S rRNA gene.

CONCLUSION

B. bifidum AGR2166 DNA was detected in maternal organs, however there is no indication that live bifidobacteria was able to translocate during pregnancy. Further studies using conventionally-raised mouse models will develop a deeper understanding of the interactions between dietary CMOF, the host, and bacteria.

Protein Malnutrition During Juvenile Age Increases Ileal and Colonic Permeability in Rats

Protein malnutrition can lead to morphological and functional changes in jejunum and ileum, affecting permeability to luminal contents. Regarding the large intestine, data are scarce, especially at juvenile age. We investigated whether low-protein (LP) diet could modify ileal and colonic permeability and epithelial morphology in young rats. Isocaloric diets containing 26% (control diet) or 4% protein were given to male rats between postnatal days 40 and 60. LP-diet animals failed to gain weight and displayed decreased plasma zinc levels (a marker of micronutrient deficiency). In addition, transepithelial electrical resistance and occludin expression were reduced in their ileum and colon, indicating increased gut permeability. Macromolecule transit was not modified. Finally, LP diet induced shortening of colonic crypts without affecting muscle thickness. These data show that protein malnutrition increases not only ileum but also colon permeability in juvenile rats. Enhanced exposure to colonic luminal entities may be an additional component in the pathophysiology of protein malnutrition.

Changes to the Intestinal Microbiome With Parenteral Nutrition: Review of a Murine Model and Potential Clinical Implications

Parenteral nutrition (PN) dependence, while life sustaining, carries a significant risk of septic complications associated with epithelial barrier dysfunction and translocation of gut-derived microbiota. Increasing evidence suggests that PN-associated changes in the intestinal microbiota play a central role in the breakdown of the intestinal epithelial barrier. This review outlines the clinical and experimental evidence of epithelial barrier dysfunction with PN, the role of gut inflammatory dysregulation in driving this process, and the role of the intestinal microbiome in modulating inflammation in the gut and systemically. The article summarizes the most current work of our laboratory and others and describes many of the laboratory findings behind our current understanding of the PN enteral environment. Understanding the interaction between nutrient delivery, the intestinal microbiome, and PN-associated complications may lead to the development of novel therapies to enhance safety and quality of life for patients requiring PN.

Feeding duodenostomy decreases the incidence of mechanical obstruction after radical esophageal cancer surgery

BACKGROUND

Nutritional support influences the outcome of gastroenterological surgery, and enteral nutrition effectively mitigates postoperative complications in highly invasive surgery such as resection of esophageal cancer. However, feeding via jejunostomy can cause complications including mechanical obstruction, which could be life threatening. From 2009, we began enteral feeding via duodenostomy to reduce the likelihood of complications. In this study, we compared duodenostomy with the conventional jejunostomy feeding, mainly looking at the catheter-related complications.

METHODS

The database records of 378 patients with esophageal cancer who underwent radical esophagectomy with retrosternal or posterior mediastinal gastric tube reconstruction in our department from January 1998 to December 2012 were examined. Of the 378 patients, 111 underwent feeding via duodenostomy (FD) and 267 underwent feeding via jejunostomy (FJ), and their records were reviewed for the following catheter-related complications: site infection, dislodgement, peritonitis, and mechanical obstruction.

RESULTS

Mechanical obstruction occurred in 12 patients in the FJ group but none in the FD group (4.5 % vs. 0 %, P = 0.023). Of the 12 cases, 7 (58.3 %) required surgery of which 2 had bowel resection due to strangulated mechanical obstruction. Catheter site infection was seen in 14 cases in the FJ group, of which 2 (14.2 %) had peritonitis following catheter dislocation, while only one case of site infection was seen in the FD group (5.2 % vs. 0.9 %, P = 0.078).

CONCLUSIONS

Feeding via duodenectomy could be the procedure of choice since neither mechanical obstruction nor relaparotomy was seen during enteral feeding through this technique.

Dark Agouti rat model of chemotherapy-induced mucositis: establishment and current state of the art

Mucositis is a major oncological problem. The entire gastrointestinal and genitourinary tract and also other mucosal surfaces can be affected in recipients of radiotherapy, and/or chemotherapy. Major progress has been made in recent years in understanding the mechanisms of oral and small intestinal mucositis, which appears to be more prominent than colonic damage. This progress is largely due to the development of representative laboratory animal models of mucositis. This review focuses on the development and establishment of the Dark Agouti rat mammary adenocarcinoma model by the Mucositis Research Group of the University of Adelaide over the past 20 years to characterize the mechanisms underlying methotrexate-, 5-fluorouracil-, and irinotecan-induced mucositis. It also aims to summarize the results from studies using different animal model systems to identify new molecular and cellular markers of mucositis.

Inflammation and Nutritional Science for Programs/Policies and Interpretation of Research Evidence (INSPIRE)

An increasing recognition has emerged of the complexities of the global health agenda—specifically, the collision of infections and noncommunicable diseases and the dual burden of over- and undernutrition. Of particular practical concern are both 1) the need for a better understanding of the bidirectional relations between nutritional status and the development and function of the immune and inflammatory response and 2) the specific impact of the inflammatory response on the selection, use, and interpretation of nutrient biomarkers. The goal of the Inflammation and Nutritional Science for Programs/Policies and Interpretation of Research Evidence (INSPIRE) is to provide guidance for those users represented by the global food and nutrition enterprise. These include researchers (bench and clinical), clinicians providing care/treatment, those developing and evaluating programs/interventions at scale, and those responsible for generating evidence-based policy. The INSPIRE process included convening 5 thematic working groups (WGs) charged with developing summary reports around the following issues: 1) basic overview of the interactions between nutrition, immune function, and the inflammatory response; 2) examination of the evidence regarding the impact of nutrition on immune function and inflammation; 3) evaluation of the impact of inflammation and clinical conditions (acute and chronic) on nutrition; 4) examination of existing and potential new approaches to account for the impact of inflammation on biomarker interpretation and use; and 5) the presentation of new approaches to the study of these relations. Each WG was tasked with synthesizing a summary of the evidence for each of these topics and delineating the remaining gaps in our knowledge. This review consists of a summary of the INSPIRE workshop and the WG deliberations.

Association Between Appendectomy and Fibrosis Progression in Nonalcoholic Fatty Liver Disease

Background

A two-hit theory explaining the progression of nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis (NASH) and fibrosis is widely accepted. Endotoxins entering the portal vein from the gut are thought to be one cause of this second hit, and the literature frequently mentions associations between gut-derived endotoxins and progression of fibrosis in NAFLD. The appendix regulates intestinal immunity to protect the gut from the invasion of bacteria and antigens. Appendectomy may thus contribute to progression of fibrosis in NAFLD, but this association has not yet been clarified. We therefore investigated the association between appendectomy and progression of fibrosis in NAFLD.

Methods

Fifty two patients with NAFLD who underwent liver biopsy in our department were included in this study. Based on Brunt’s scores, patients with NAFLD were classified into a mild fibrosis group and advanced fibrosis group.

Results

History of appendectomy was found to be significantly more frequent in patients with advanced fibrosis than in patients with mild fibrosis (P = 0.014). Multivariate logistic analysis was conducted with age, sex, albumin, platelet count, steatosis grade, and history of appendectomy as covariates and advanced fibrosis as the dependent variable. Significant differences were identified for platelet count and history of appendectomy, identifying these as independent risk factors for advanced fibrosis in NAFLD patients. The odds ratio for appendectomy history was 39.415 (P = 0.044).

Conclusions

History of appendectomy was significantly more frequent in NAFLD patients with advanced fibrosis, suggesting that appendectomy may represent a risk factor for advanced fibrosis in NAFLD.

Feeding jejunostomy tubes placed during esophagectomy: are they necessary?

BACKGROUND

Jejunostomy tubes (JT) are routinely placed at the time of esophagectomy and can be associated with low--but not insignificant--morbidity. Increased emphasis on evidence-based medicine prompted this critical review of JT use during esophagectomy and factors that predict the absolute need for JT.

METHODS

All esophagectomies performed at one tertiary care institution from 1995 through 2009 were retrospectively reviewed. Statistical analyses were performed to determine preoperative variables that would assist in selecting patients who should receive a JT.

RESULTS

A total of 143 JTs were placed in 151 patients undergoing esophagectomy for carcinoma (83.4%), high-grade dysplasia (13.2%), and perforation (2.6%). Of these, 110 patients (76.9%) had returned to oral intake before discharge (median, 7 days), whereas 33 patients (23.1%) still required tube feedings. Of 8 patients who did not undergo intraoperative JT placement, 6 had resumed oral intake at discharge. Two patients were discharged on total parenteral nutrition. Logistic regression analysis of preoperative variables showed a body mass index of less than 18.5 kg/m2 conferred a likelihood of requiring a JT at discharge (odds ratio, 7.56; p<0.05). Age, sex, albumin level, type of esophagectomy, histology, stage, preoperative neoadjuvant therapy, and type of cancer were not significant predictors of JT need at discharge.

CONCLUSIONS

The only absolute indication for JT placement after esophagectomy was a body mass index of less than 18.5 kg/m2. Other patients may have selective JT placement based on the surgeon's judgment.

Combining enteral with parenteral nutrition to improve postoperative glucose control

The provision of parenteral nutrition (PN) to ‘stressed’ patients often results in hyperglycaemia, which may be detrimental. In animal models limited amounts of enteral nutrition (EN) improve intestinal integrity and stimulate intestinal incretin production, which may lead to improved glucose control. We set out to assess if combining EN with PN results in improved glucose homeostasis rather than PN given alone. We conducted a randomised trial in a university teaching hospital of patients undergoing a ‘curative’ oesophagectomy for adenocarcinoma. Differences between the two intervention groups were assessed for continuous glucose measurement, insulin sensitivity using insulin tolerance tests (ITT) and homeostasis model analysis (HOMA), the incretin glucose-dependent insulinotropic polypeptide (GIP) and intestinal permeability. The combination of PN with EN resulted in lower interstitial glucose concentrations (P = 0·002), reduced insulin resistance, improved insulin sensitivity (HOMA-insulin resistance (IR)P = 0·045; HOMA βP = 0·037; ITTP = 0·006), improved intestinal permeability (P < 0·001) and increased GIP (P = 0·01) when compared with PN alone. The combination of EN with PN, when compared with PN alone, results in reduced glucose concentrations, reduced insulin resistance, increased incretins and improvements in intestinal permeability.

Probiotic acidified formula in an animal model reduces pulmonary and gastric bacterial load

BACKGROUND/PURPOSE

We previously reported that a diet acidified with citric acid effectively reinforces gastric acid protection against bacterial colonization and translocation. In this study, our objective was to examine a biologically acidified formula hypothesized to be more physiologic than formula acidified with free acid. This study was Institutional Animal Care and Use Committee (IACUC) approved and designed to determine whether this diet is better tolerated and equally effective to acidification with citric acid against gut colonization and subsequent bacterial translocation in a premature infant rabbit model.

METHODS

A total of 89 rabbit pups born via cesarean delivery 1 day preterm were randomly assigned to 3 feeding groups: Pelargon Nestle at pH 4.55; NAN Nestle, a control diet at pH 7.0 with similar composition; and NAN Nestle acidified in the laboratory with citric acid at pH 4.55. Pups were gavage fed every 12 hours with Enterobacter cloacae challenges of 10 colony-forming units per milliliter of diet per feed and killed on day 3 of life. Lungs, liver, spleen, mesenteric lymph nodes, stomach, and cecum were cultured and quantitatively analyzed for target organism growth and statistically analyzed using chi(2) and Kruskal-Wallis tests.

RESULTS

Pelargon, compared to acidified NAN and NAN, significantly reduced the incidence of gastric colonization (15/33 [45%], 21/27 [78%], and 25/29 [86%], respectively; P < .01) and pulmonary colonization (10/33 [30%], 19/27 [70%], 21/29 [72%]; P < .01). Comparing the bacterial logs of colonized groups, the same benefit is observed in the lungs (0.77 +/- 1.22, 1.89 +/- 1.41, 2.12 +/- 1.47; P < .01). Gut colonization and bacterial translocation were equivalent between treatment groups (mesenteric lymph nodes: 10/33 [30%], 11/27 [40%], 8/29 [27%]; spleen: 10/33 [30%], 7/27 [26%], 8/29 [27%]; liver: 10/33 [30%], 6/27 [22%], 9/29 [31%]; cecum: 33/33 [100%], 27/27 [100%], 29/29 [100%]).

CONCLUSION

Biologically acidified formula demonstrated superior protection against pulmonary and gastric colonization compared to normal pH and diets acidified with free acid. Its effects may potentially reduce clinical pulmonary infection.

Immunological disturbance and infectious disease in anorexia nervosa: a review

OBJECTIVE

Severely malnourished patients with anorexia nervosa (AN) are reported to show fewer symptomatic viral infections and a poorer response to bacterial infection than controls. They are also reported to show mild immune system changes, although the relevance of these to altered infection disease presentation in AN and AN pathophysiology is unknown. Thus, in this paper, we suggest a range of immune system changes that might underpin these altered responses to common pathogens, and review a number of recent infectious disease findings for their utility in explaining the pathophysiology of AN.

METHODS

A systematic review of the literature pertaining to immunity and infectious disease in AN was performed.

RESULTS

AN is associated with leucopenia, and the increased spontaneous and stimulated levels of proinflammatory cytokines [i.e. interleukin (IL)-1β, IL-6 and tumour necrosis factor α). A range of less consistent findings are also reviewed. Most of these data were not controlled for length of illness, degree of malnutrition, micronutrient or vitamin deficiencies or recent refeeding and starvation.

CONCLUSION

Cytokine disturbances have been suggested to be causally related to AN symptomatology and pathophysiology of AN, although the evidence supporting this assertion is lacking. Immune and cytokine changes in AN do, however, occur in association with a decreased incidence of symptomatic viral infection, decreased clinical response to bacterial infection leading to delayed diagnosis and increased morbidity and mortality associated with the infections.

Use of methylene blue spectrophotometry to detect subclinical aspiration in enterally fed intubated pediatric patients

OBJECTIVE

Enteral feeding is widely used in ventilated patients admitted to pediatric intensive care units. Although studies in adult patients have shown that the site of feeding (stomach vs. small intestine) may be associated with aspiration pneumonia, there are no such reports in critically ill pediatric patients. We hypothesized that in intubated pediatric patients, there was no difference in the frequency of aspiration between nasogastric and postpyloric enteral feeding.

DESIGN

Randomized, prospective clinical study.

SETTING

Single pediatric intensive care unit of a tertiary care children's hospital.

PATIENTS

Forty-four intubated patients (< or = 18 yrs old).

INTERVENTIONS

Intubated patients were randomized to receive either nasogastric (n = 27) or postpyloric (n = 17) enteral feeding. Feeding tube placement by the bedside nurse was confirmed by abdominal radiograph. Methylene blue was added at a standard dilution to an age-appropriate formula. Tracheal secretions were suctioned every 8 hrs, tested for blue color by observation, and analyzed via spectrophotometry. Patients were followed until feeds were stopped for anticipated extubation. Aspiration pneumonia was defined using criteria of the Centers of Disease Control and Prevention (CDC).

MEASUREMENTS AND MAIN RESULTS

Methylene blue was detected in two patients in the postpyloric group by spectrophotometry. None of the patients met the CDC criteria for aspiration. There was no difference in the frequency of aspiration between the two groups (p < .07). The time until beginning feedings in the postpyloric group was greater than that for the nasogastric group (18-24 hrs vs. 6 hrs, p < .05). The postpyloric group required more abdominal radiographs compared with the nasogastric group (three radiographs vs. one, p < .05).

CONCLUSIONS

Use of nasogastric feeding shortens the time needed to reach nutritional goals and reduces the number of radiographic studies. Nasogastric feeding demonstrates no increase in aspiration compared with postpyloric feeding in intubated pediatric patients.

Infection prophylaxis of gunshot wounds using probiotics

OBJECTIVE

To report a new method of surgical infection prophylaxis for postoperative gunshot wounds to the extremities.

METHOD

Gunshot wounded animals were divided into three groups: treatment (probiotic Sporobacterin), antibiotic (cephalosporin cefamezin) and control (no treatment). Histological studies of wound-bed tissue were taken on days 1, 3, 5 and 10 of the study.

RESULTS

The probiotic administered per os was more effective than antibiotics for prophylaxis of surgical infection.

CONCLUSION

The probiotic's effect is based on the natural defence mechanism activated after injury--the bacterial translocation of saprophytic bacteria from the gut to the wound.

DECLARATION OF INTEREST

None.

Effects of immunonutrition on intestinal mucosal apoptosis, mucosal atrophy, and bacterial translocation in head injured rats

BACKGROUND

Immunonutrition has been demonstrated to modulate gut function, reduce infectious complications, hospital stay, and ventilator days in the critical patients.

AIM OF THE STUDY

We assessed the effect of immunonutrition for the prevention of intestinal mucosal atrophy, apoptosis, and bacterial translocation in head injured rats.

METHODS

Thirty five rats were randomised into 5 groups. Following moderate closed head injury, in Group 1; Standard Enteral Nutrition, Group 2; Immunonutrition, Group 3; TPN, Group 4; pe. saline were applied. Group 5 was control group (chow-fed). The rats were sacrificed and segments of the ileum were removed for histologic examination, and samples of tissues taken for microbiologic evaluation.

RESULTS

Both intestinal apoptosis and mucosal atrophy were significantly lower in Group 2 and Group 5 (p<0.008). Bacterial translocation was significantly lower in Group 2 than Group 1 (p<0.008).

CONCLUSION

The enteral immunonutrition prevents intestinal barrier function in brain injured rats.

Dietary fructo-oligosaccharides dose-dependently increase translocation of salmonella in rats

Prebiotics, such as fructo-oligosaccharides (FOS), stimulate the protective gut microflora, resulting in an increased production of organic acids. This may result in increased luminal killing of acid-sensitive pathogens. However, host defense against invasive pathogens, like salmonella, also depends on the barrier function of the intestinal mucosa. Rapid fermentation of prebiotics leading to high concentrations of organic acids may impair the barrier function. Therefore, we determined the dose-dependent effect of dietary FOS on the resistance of rats to Salmonella enteritidis. Male Wistar rats were fed restricted quantities of a "humanized" purified diet supplemented with 0, 3 or 6 g/100 g of FOS (n = 7 in the 6% FOS group and n = 8 in the other diet groups). After an adaptation period of 2 wk, rats were orally infected with 1.7 x 10(10) colony-forming units of S. enteritidis. Supplement-induced changes in the intestinal microflora and fecal cation excretion were determined before and after infection. Cytotoxicity of fecal water was determined with an in vitro bioassay, and fecal mucins were quantified fluorimetrically. Colonization of S. enteritidis was determined by quantification of salmonella in cecal contents and mucosa. Translocation of S. enteritidis was quantified by analysis of urinary nitric oxide metabolites in time. Before infection, FOS decreased cecal and fecal pH, increased fecal lactic acid concentration and increased bifidobacteria and enterobacteria. FOS also increased cytotoxicity of fecal water and fecal mucin excretion, indicating mucosal irritation. Remarkably, FOS dose-dependently increased salmonella numbers in cecal contents and mucosa and caused a major increase in infection-induced diarrhea. In addition, FOS enhanced translocation of salmonella. Thus, in contrast to most expectations, FOS dose-dependently impairs the resistance to salmonella infection in rats. These results await verification by other controlled animal and human studies.

Role of the gut in the course of severe acute pancreatitis

INTRODUCTION

The pathogenesis of acute pancreatitis remains elusive. Sepsis and multiple organ failure continue to cause death (overall mortality rate, approximately 10%) despite immense improvements in supportive, radiologic, and surgical therapy. The gut appears to play a key role in the development of these complications.

AIM

To critically review the evidence implicating the gut in the pathogenesis of acute pancreatitis.

METHODS

Relevant English-language literature or abstracts cited in the MEDLINE database were reviewed.

RESULTS AND CONCLUSION

Gram-negative enteric organisms account for most infections of pancreatic necrosis and subsequent sepsis, which suggests the gut as a source. Intestinal permeability is increased early in patients with severe acute pancreatitis and correlates with endotoxemia, which suggests translocation as a possible mechanism. The pathogenesis of the deranged function of the gut mucosal barrier and the possible sites of increase in intestinal permeability are discussed. The gut also plays a role in priming neutrophils and the release of inflammatory cytokines, which initiate and propagate nearly all the detrimental consequences of severe inflammation and sepsis. Future research avenues and potential therapeutic measures that may restore and preserve gut barrier function are explored.

Inosine modulates gut barrier dysfunction and end organ damage in a model of ischemia-reperfusion injury

INTRODUCTION

Gut barrier failure is an important source of morbidity in critically ill patients, and patients undergoing aortic cross-clamp. Inosine, an endogenous purine nucleoside without known side effects, formed from the breakdown of adenosine by adenosine deaminase, has been shown to modify the effects of hypoxia on various tissues, including the heart and the brain.

MATERIALS AND METHODS

This study examined the effect of inosine on ischemia-reperfusion-induced gut barrier dysfunction and on the associated lung injury. Twenty-four male Sprague-Dawley rats were divided into three groups. Eight were subjected to 60 min of superior mesenteric artery occlusion followed by 4 h of reperfusion. Eight had 100 mg/kg inosine prior to ischemia-reperfusion and 8 had sham laparotomy with encircling but not occlusion of the superior mesenteric artery.

RESULTS

Rats treated with inosine had significantly less gut barrier dysfunction. Rats subjected to SMAO sustained a substantial lung injury and this was attenuated by inosine treatment. Serum cytokine levels were also significantly lower.

CONCLUSIONS

We conclude that inosine has a beneficial effect in modulating both gut barrier dysfunction and distant organ injury in response to gut ischemia-reperfusion.

Key nutrients and growth factors for the neonatal gastrointestinal tract

The nutritional support of gastrointestinal growth and function is an important consideration in the clinical care of neonatal infants. In most health infants, the provision of either breast milk or formula seems to support normal intestinal mucosal growth, but the most significant advantages of breast milk may be for host defense or gut barrier-related functions that are involved in reducing infection. The specific effects of various milk-borne growth factors on key mucosal immune and barrier functions are likely to provide valuable new clues to the advantages of human milk. A substantial number of preterm, low-birth weight babies or those suffering from compromised intestinal function, however, often cannot tolerate oral feedings and instead receive TPN. The consequences of TPN on gastrointestinal function and how this contributes to morbidity of these infants warrants further study, with respect to both clinical and basic research questions. Although enteral nutrition seems to be a critical stimulus for intestinal function, the minimal amounts and composition of nutrients necessary to maintain specific intestinal functions remain to be established. The experimental tools exist to start defining the specific nutrient requirements for the infant gut and some of these nutrients are known (e.g., glutamate, glutamine, and threonine). Peptide growth factors and gut hormones clearly play a role in gut growth and in several ways mediate the trophic actions of enteral nutrition. Although a number of these growth factors are good candidates for therapeutic use, their clinical application in the management of gastrointestinal insufficiency and disease has been slow. The emergence of GLP-2 as a trophic peptide that seems to target the gut is a promising candidate on the horizon.

Late hematogenous infection of subcutaneous implants in rats

Late biomaterial-centered infection is a major complication associated with the use of biomaterial implants. In this study biomaterials that had been implanted subcutaneously in rats were hematogenously challenged with bacteria 4 weeks after implantation. Bacteria were spread either by intravenous injection or by stimulation of bacterial translocation. It was found that none of the biomaterials was infected by hematogenous spread, whereas 5% of the implants were infected by perioperative contamination. We conclude that late hematogenous infection of subcutaneous biomaterials does not occur in the rat. For humans as well, there are growing doubts whether implants actually become infected through hematogenous routes; it is thought that late infections may be caused by delayed appearance of perioperatively introduced bacteria.

Does the supplementation of the formula with fibre increase the risk of gastro-oesophageal reflux during enteral nutrition? A human study

BACKGROUND & AIMS

Fibre-supplements in enteral feeding could increase the risk of gastro-oesophageal reflux (GOR). The aim of this study was to assess in humans the physiological effects of the supplementation of the enteral diet with different types of dietary fibre on gastro-oesophageal reflux episodes, gastric acidity and gastric emptying.

METHODS

pH profiles were compared in 12 healthy volunteers between three different formula (500 kcal, 250 mL x h-1) delivered in a random order and containing either no fibre, either soy polysaccharide fibre only or mixed fibre from pea and inuline. Enteral diets were instilled through a nasogastric tube. Oesophageal and gastric pH recordings were combined with the ultrasound measurement of gastric antral area during the infusion.

RESULTS

More GOR were observed with a fibre-free diet (median 4, range 1-10) than with a mixed (median 1.5, range 0-5) (P=0.04) or soy polysaccharide fibre (median 1.5, range 0-5) (P=0.04) diet. The median duration of GOR was longer with the mixed fibre (median 3.6, range 1.8-7.2) than with the fibre-free diet (mean 1.8 min, range 1-3.6) (P<0.05). The number of GOR episodes lasting more than 5 min, the duration of the longest GOR and the percent of time under pH 4 were not significantly different with the three diets. The intragastric pH profile and the ultrasound antral area were not different with all three diets.

CONCLUSIONS

Addition of fibre to the enteral formula had limited effects on the onset of GOR episodes. It decreased the number of GOR but increased their duration. These effect were more pronounced with the formula containing soluble fibre. At variance, the addition of fibre had no significant effect on gastric emptying and gastric acid secretion.

Small intestine epithelial barrier function is compromised in pigs with low feed intake at weaning

Compromising alterations in gastrointestinal architecture are common during the weaning transition of pigs. The relation between villous atrophy and epithelial barrier function at weaning is not well understood. This study evaluated in vitro transepithelial transport by Ussing metabolic chambers, local alterations in T-cell subsets and villous architecture at low energy intake level and their relation with lactose/protein ratios in the diet. Pigs (n = 66, 26 d old) were sampled either at weaning (d 0), d 1, 2 or 4 postweaning. Piglets received one of three diets at a low energy intake level, which differed in lactose and protein ratio as follows: low lactose/high protein (LL/HP), control (C), or high lactose/low protein (HL/LP). Mean digestible energy intake was 648 kJ/pig on d 1, 1668 kJ/pig on d 2, 1995 kJ/pig on d 3 and 1990 kJ/pig on d 4 postweaning. The CD4(+)/CD8(+) T-lymphocytes ratio decreased after weaning (P < 0.05). Decreased paracellular transport (P < 0.01), greater villous height (P < 0.01), shallower crypts and lower villus/crypt ratios (P < 0.01) were observed on d 2 compared with d 0. Piglets consuming the HL/LP diet tended to have less paracellular transport (P < 0.10) and greater villous height (P < 0.10) compared with piglets fed the other diets. During the first 4 d postweaning, the effect of diet composition on mucosal integrity was not as important as the sequential effects of low energy intake at weaning. Stress and diminished enteral stimulation seem to compromise mucosal integrity as indicated by increased paracellular transport and altered T-cell subsets.

Adaptation of bacteria to the intestinal niche: probiotics and gut disorder

The gastrointestinal tract is a complex ecosystem host to a diverse and highly evolved microbial community composed of hundreds of different microbial species. The interactions that occur between this complex microbial community and the human host have become the focus of scientific research due to increases in the incidence of illnesses associated with deficient or compromised microflora (e.g., gastrointestinal tract infections, inflammatory bowel disease (Crohn's disease and ulcerative colitis), irritable bowel syndrome, antibiotic-induced diarrhea, constipation, food allergies, cardiovascular disease, and certain cancers). Effective multidisciplinary research programs now complement conventional microbiology with molecular ecology techniques to provide culture-independent analysis of the gastrointestinal ecosystem. Furthermore, as we acquire an understanding of gut microflora composition and processes such as intestinal adherence, colonization, translocation, and immunomodulation, we are also elucidating mechanisms by which these can be influenced. This knowledge not only allows scientists to define the activities and interactions of "functional food"-borne beneficial bacteria in the gut, but will also provide the scientific basis for the development of innovative biotechnology-based products tailored to prevent specific diseases and promote overall human gastrointestinal health.

Nasogastric feeding in severe acute pancreatitis may be practical and safe

BACKGROUND

Severe acute pancreatitis may be protracted and some form of nutritional support is frequently required to maintain the patient's nutritional status. Recent work has suggested that enteral feeding via a jejunal route of delivery may reduce the magnitude of the inflammatory response. Insertion of nasojejunal (NJ) tubes in the patient with severe acute pancreatitis involves both delay and inconvenience. We undertook a prospective, feasibility study to assess the safety and practicability of nasogastric (NG) feeding in patients with severe acute pancreatitis.

PATIENTS AND METHODS

Twenty-six patients with objective evidence of severe acute pancreatitis received nasogastric feeding within 48 h of admission to our unit.

RESULTS

Etiology was identified as cholelithiasis (18 patients), ethanol (5), and miscellaneous (3). The median Glasgow score was 4 (range 2-7), APACHE II score 10 (4-28), and C-reactive protein concentration 286 mg/L (79-469). Fifteen patients had pancreatic and/or peripancreatic necrosis. Eleven patients developed severe organ failure, necessitating ventilatory support. Six developed multiple organ system failure, requiring inotropic support and/or renal dialysis. There were four deaths (15.3%). Nine patients underwent early, and nine late, ERCP, respectively; six necrosectomy (5 proven infected necrosis, 1 continued deterioration despite maximal support) and 4 patients internal drainage of a pseudocyst. The feed was well-tolerated in 22 patients. In 3 patients gastric stasis proved troublesome. There was no evidence of clinical or biochemical deterioration on commencing nasogastric feeding.

CONCLUSION

It would appear that early NG feeding is usually possible in severe acute pancreatitis. In most patients it appears safe, well-tolerated, and worthy of further study.

Enteral feeding in the critically ill: comparison between the supine and prone positions: a prospective crossover study in mechanically ventilated patients

INTRODUCTION

Prone position is effective in mechanically ventilated patients to improve oxygenation. It is unknown if prone position affects gastric emptying and the ability of continued enteral feeding.

AIM

To determine tolerance of enteral feeding by measuring gastric residual volumes in enterally fed patients during supine and prone positions.

METHODS

Consecutive mechanically ventilated intensive care patients who were turned to prone position were included. All patients were studied for 6 hours in supine position, immediately followed by 6 hours in prone position, or vice versa. The rate of feeding was unchanged during the study period. Gastric residual volume was measured by suctioning the naso-gastric tube after 3 and 6 hours in the same position. Wilcoxon test and regression analysis were used for analysis.

RESULTS

The median volume of administered enteral feeds was 95 ml after 6 hours in supine position and 110 ml after 6 hours in prone position (P = 0.85). In 10 patients, a greater gastric residual volume was found in prone position. In eight others a greater volume was found in supine position. In 18 of 19 patients, gastric residual volumes in both positions were > or = 150 ml in 6 hours or < or = 150 ml in 6 hours. Significantly more sedatives were used in prone position. Regression analysis excluded dopamine dose and the starting position as confounders.

CONCLUSION

Our results suggest that enteral feeding can be continued when a patient is turned from supine to prone position or vice versa. The results indicate that patients with a clinically significant gastric residual volume in one position are likely to have a clinically significant gastric residual volume in the other position.

How do fiber-supplemented formulas affect antroduodenal motility during enteral nutrition? A comparative study between mixed and insoluble fibers

BACKGROUND

Fiber supplementation during enteral nutrition has been recommended, but the effect of soluble compared with insoluble fiber supplements on antroduodenal motility is unknown.

OBJECTIVE

The objective of this study was to compare antroduodenal motor patterns in 8 healthy volunteers during and after gastric infusion of 3 different diets: a fiber-free diet, an insoluble-fiber diet, and a mixed-fiber diet (50% soluble fiber and 50% insoluble fiber).

DESIGN

Manometric studies with the 3 different diets (2100 kJ) were performed in random order. Antroduodenal motility was monitored continuously for 6 h by using a pneumohydraulic system to calculate the number, amplitude, and duration of the pressure waves; the area under the curve (AUC); and the percentage of time occupied by motor activity before, during, and after each type of infusion. Variations in antral areas were measured by ultrasonography.

RESULTS

The gastric motor response was significantly higher, whatever the diet, in the distal antral recording site than in the 2 more proximal sites. In the proximal but not the distal antrum, the number of waves, the AUC, and the percentage of time occupied by motor activity were higher (P: < 0.04) with the mixed-fiber than with the insoluble-fiber diet. No significant differences in variations of antral area were observed among the 3 diets. In the duodenum, motor variables were not significantly different among the 3 diets.

CONCLUSIONS

A gastric infusion induced a greater motor response in the distal than in the proximal antrum. A mixed-fiber diet was associated with significantly greater proximal antral motility than was an insoluble-fiber diet. There was no significant difference among the 3 formulas in duodenal motor variables or in variations in antral area as measured by ultrasound.

Nasogastric feeding in severe acute pancreatitis may be practical and safe

BACKGROUND

Severe acute pancreatitis may be protracted and some form of nutritional support is frequently required to maintain the patient's nutritional status. Recent work has suggested that enteral feeding via a jejunal route of delivery may reduce the magnitude of the inflammatory response. Insertion of nasojejunal (NJ) tubes in the patient with severe acute pancreatitis involves both delay and inconvenience. We undertook a prospective, feasibility study to assess the safety and practicability of nasogastric (NG) feeding in patients with severe acute pancreatitis.

PATIENTS AND METHODS

Twenty-six patients with objective evidence of severe acute pancreatitis received nasogastric feeding within 48 h of admission to our unit.

RESULTS

Etiology was identified as cholelithiasis (18 patients), ethanol (5), and miscellaneous (3). The median Glasgow score was 4 (range 2-7), APACHE II score 10 (4-28), and C-reactive protein concentration 286 mg/L (79-469). Fifteen patients had pancreatic and/or peripancreatic necrosis. Eleven patients developed severe organ failure, necessitating ventilatory support. Six developed multiple organ system failure, requiring inotropic support and/or renal dialysis. There were four deaths (15.3%). Nine patients underwent early, and nine late, ERCP, respectively; six necrosectomy (5 proven infected necrosis, 1 continued deterioration despite maximal support) and 4 patients internal drainage of a pseudocyst. The feed was well-tolerated in 22 patients. In 3 patients gastric stasis proved troublesome. There was no evidence of clinical or biochemical deterioration on commencing nasogastric feeding.

CONCLUSION

It would appear that early NG feeding is usually possible in severe acute pancreatitis. In most patients it appears safe, well-tolerated, and worthy of further study.

Nutritional support of the cancer patient: issues and dilemmas

Malnutrition in cancer patients results from multifactorial events and is associated with an alteration of quality of life and a reduced survival. A simple nutritional assessment program and early counselling by a dietitian are essential to guide nutritional support and to alert the physician to the need for enteral (EN) or parenteral nutrition (PN). A daily intake of 20-35 kcal/kg, with a balanced contribution of glucose and lipids, and of 0.2-0.35 g nitrogen/kg is recommended both for EN and PN, with an adequate provision of electrolytes, trace elements and vitamins. EN, always preferable for patients with an intact digestive tract, and PN are both safe and effective methods of administering nutrients. The general results in clinical practice suggest no tumor growth during nutritional support. The indiscriminate use of conventional EN and PN is not indicated in well-nourished cancer patients or in patients with mild malnutrition. EN or PN is not clinically efficacious for patients treated with chemotherapy or radiotherapy, unless there are prolonged periods of GI toxicity, as in the case of bone marrow transplant patients. Severely malnourished cancer patients undergoing major visceral surgery may benefit from perioperative nutritional support, preferably via enteral access. Nutritional support in palliative care should be based on the potential risks and benefits of EN and PN, and on the patient's and family's wishes. Research is currently directed toward the impact of nutritional pharmacology on the clinical outcome of cancer patients. Glutamine-supplemented PN is probably beneficial in bone marrow transplant patients. Immune diets are likely to reduce the rate of infectious complications and the length of hospital stay after GI surgery. Further studies are needed to determine the efficacy of such novel approaches in specific populations of cancer patients, and should also address the question of the overall cost-benefit ratio of nutritional pharmacology, and the effect of nutritional support on length and quality of life.

Management of cholestasis in infants with very low birth weight

Infants with very low birth weight (VLBW) are at increased risk of cholestasis when compared with older infants and children. Factors associated with this increased risk of cholestasis include immaturity of the biliary excretory system, a diminished immune response to sepsis, an increased incidence of necrotizing enterocolitis and short bowel syndrome, as well as an increased exposure to parenteral nutrition (PN). The current literature on cholestasis in VLBW infants and the factors that mediate the initiation and progression of cholestatic liver damage is reviewed. A protocol for managing infants with cholestatic jaundice is presented, and a case report is included that shows use of the protocol to normalize the bilirubin in a VLBW infant with severe cholestatic jaundice.

Small amount of low-residue diet with parenteral nutrition can prevent decreases in intestinal mucosal integrity

OBJECTIVE

To investigate the suitable combination ratio of low-residue diet (LRD) and parenteral nutrition (PN) for nutritional support of surgical patients.

SUMMARY BACKGROUND DATA

Bacterial translocation (BT) is a severe complication of total parenteral nutrition (TPN). However, it is sometimes impossible to supply sufficient amounts of nutrients to surgical patients by the enteral route. The authors reported previously that concomitant use of LRD with PN provided preferable nutritional support for patients undergoing surgery for colorectal cancer.

METHODS

Ninety male Donryu rats were used for three experiments. In experiment 1, rats were divided into two groups to receive TPN or total enteral nutrition with LRD. In experiment 2, rats were divided into six groups, receiving variable amounts of LRD. In experiment 3, rats were divided into five groups to receive isocaloric nutritional support with variable proportions of PN and LRD. Intestinal permeability was assessed by monitoring urinary excretion of phenolsulfonphthalein. BT was assessed in tissue cultures of mesenteric lymph nodes and spleen.

RESULTS

In experiment 1, increases in intestinal permeability and BT were observed in rats maintained on 7-day TPN, but not in those maintained on total enteral nutrition for up to 14 days. In experiment 2, the changes in body weight of rats were correlated with the dose of LRD. However, the intestinal permeability was increased only in rats receiving LRD at 15 kcal/kg per day. In experiment 3, additive LRD corresponding to 15% of total caloric intake prevented increases in intestinal permeability and BT.

CONCLUSION

Combined nutritional therapy consisting of PN and small amounts of LRD can provide better nutritional support than TPN for surgical patients.

Gut mucosa morphology and microflora changes in malnourished mice after renutrition with milk and administration of Lactobacillus casei

Nutrition plays a key role in maintaining the balance of the intestinal microflora. Malnutrition disturbs the ecological barrier and induces histological damage. We evaluated modifications induced by renutrition with nonfat milk (NFM) and Lactobacillus casei administration (for 2 days) on the bacterial gut population and structural and ultrastructural gut modifications in malnourished mice. Balb/c mice suffering from a malnutrition process immediately after weaning (for 21 days) were divided into four groups and were given NFM for 0, 7, 14, and 21 days. Another group was treated in a similar way, but after different periods of NFM administration, mice in this group received L. casei for two consecutive days. All experimental animals were sacrificed by cervical dislocation, and both the microflora and the histological structure of the intestine were studied. In malnourished animals, a decrease in the numbers of Lactobacillus and anaerobic microorganisms was observed, whereas there was an increase in the number of Enterobacteriaceae. In animals treated with NFM and NFM plus L. casei, we could observe an important improvement in the microflora in the small and large intestines but no differences between both treatments. Structural and ultrastructural studies showed a slight improvement 7 days after treatment with NFM, and for 14 and 21 days after renutrition, the mice showed normal intestinal villi, whereas the additional feeding with L. casei for two consecutive days, after different periods of renutrition, yielded an earlier improvement (7 days).

Mucosal barrier injury: biology, pathology, clinical counterparts and consequences of intensive treatment for haematological malignancy: an overview

Mucositis is an inevitable side-effect of the conditioning regimens used for haematopoietic stem cell transplantation. The condition is better referred to as mucosal barrier injury (MBI) since it is primarily the result of toxicity and is a complex and dynamic pathobiological process manifested not only in the mouth but also throughout the entire digestive tract. A model has been proposed for oral MBI and consists of four phases, namely inflammatory, epithelial, ulcerative and healing phases. A variety of factors are involved in causing and modulating MBI including the nature of the conditioning regimen, the elaboration of pro-inflammatory and other cytokines, translocation of the resident microflora and their products, for example, endotoxins across the mucosal barrier, exposure to antimicrobial agents and whether or not the haematopoietic stem cell graft is from a donor. Neutropenic typhlitis is the most severe gastrointestinal manifestation of MBI, but it also influences the occurrence of other major transplant-related complications including acute GVHD, veno-occlusive disease and systemic infections. The pathobiology, clinical counterparts and the means of measuring MBI are discussed together with potential approaches for prevention, amelioration and, perhaps, even cure. Bone Marrow Transplantation (2000) 25, 1269-1278.