Transcriptional Landscape of Human Tissue Lymphocytes Unveils Uniqueness of Tumor-Infiltrating T Regulatory Cells

Tumor-infiltrating regulatory T lymphocytes (Treg) can suppress effector T cells specific for tumor antigens. Deeper molecular definitions of tumor-infiltrating-lymphocytes could thus offer therapeutic opportunities. Transcriptomes of T helper 1 (Th1), Th17, and Treg cells infiltrating colorectal or non-small-cell lung cancers were compared to transcriptomes of the same subsets from normal tissues and validated at the single-cell level. We found that tumor-infiltrating Treg cells were highly suppressive, upregulated several immune-checkpoints, and expressed on the cell surfaces specific signature molecules such as interleukin-1 receptor 2 (IL1R2), programmed death (PD)-1 Ligand1, PD-1 Ligand2, and CCR8 chemokine, which were not previously described on Treg cells. Remarkably, high expression in whole-tumor samples of Treg cell signature genes, such as LAYN, MAGEH1, or CCR8, correlated with poor prognosis. Our findings provide insights into the molecular identity and functions of human tumor-infiltrating Treg cells and define potential targets for tumor immunotherapy.

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Transcriptome analysis performed on tumor-resident CD4⁺ Th1, Th17, and Treg cells

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Tumor-infiltrating Treg cells are defined by the expression of signature genes

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Treg-specific signature genes correlate with patients’ survival in both CRC and NSCLC

A randomized controlled trial of preoperative oral supplementation with a specialized diet in patients with gastrointestinal cancer

BACKGROUND & AIMS

Perioperative nutrition with specialized enteral diets improves outcome when compared with standard formulas. A post-hoc analysis suggested preoperative administration as the most important period. Thus, we designed a study to understand prospectively whether preoperative supplementation could be as efficacious as the perioperative approach and superior to a conventional treatment (no artificial nutrition) in reducing postoperative infections and length of hospital stay.

METHODS

A total of 305 patients with preoperative weight loss <10% and cancer of the gastrointestinal tract were randomized to receive the following: (1) oral supplementation for 5 days before surgery with 1 L/day of a formula enriched with arginine, omega-3 fatty acids, and RNA, with no nutritional support given after surgery (preoperative group, n = 102); (2) the same preoperative treatment plus postoperative jejunal infusion with the same enriched formula (perioperative group, n = 101); and (3) no artificial nutrition before and after surgery (conventional group; n = 102).

RESULTS

The 3 groups were comparable for all baseline and surgical characteristics. Intention-to-treat analysis showed a 13.7% incidence of postoperative infections in the preoperative group, 15.8% in the perioperative group, and 30.4% in the conventional group (P = 0.006 vs. preoperative; P = 0.02 vs. perioperative). Length of hospital stay was 11.6 +/- 4.7 days in the preoperative group, 12.2 +/- 4.1 days in the perioperative group, and 14.0 +/- 7.7 days in the conventional group (P = 0.008 vs. preoperative and P = 0.03 vs. perioperative).

CONCLUSIONS

Preoperative supplementation is as effective as perioperative administration in improving outcome. Both strategies seem superior to the conventional approach.

Postoperative enteral versus parenteral nutrition in malnourished patients with gastrointestinal cancer: a randomised multicentre trial

BACKGROUND

Although current opinion favours the use of enteral over parenteral nutrition, the clinical benefits of early postoperative nutrition in patients undergoing elective surgery have never been clearly shown. We aimed to test the hypothesis that postoperative enteral nutrition is better (fewer postoperative complications) than parenteral nutrition containing similar energy and nitrogen amounts (112 kJ kg(-1) day(-1) and 1.4 g aminoacid kg(-1) day(-1)).

METHODS

We did a randomised multicentre clinical trial in patients with gastrointestinal cancer who were malnourished and candidates for major elective surgery. 159 patients were assigned to enteral nutrition and 158 to parenteral nutrition. The primary endpoint was the occurrence of postoperative complications, and secondary endpoints were length of postoperative hospital stay, adverse effects, and treatment crossover. Analysis was by intention to treat.

FINDINGS

Postoperative complications occurred in 54 (34%) patients fed enterally versus 78 (49%) fed parenterally (relative risk 0.69, 95% CI 0.53-0.90, p=0.005). Length of postoperative stay was 13.4 days and 15.0 days in the enteral nutrition and parenteral nutrition groups, respectively (p=0.009). Adverse effects occurred in 56 (35%) patients fed enterally versus 22 (14%) patients fed parenterally (2.50, 1.61-3.86, p<0.0001). 14 (9%) patients on enteral nutrition had to switch to parenteral nutrition, whereas none of those fed parenterally crossed over to enteral feeding.

INTERPRETATION

We conclude that early enteral nutrition significantly reduces the complication rate and duration of postoperative stay compared with parenteral nutrition, although parenteral nutrition is better tolerated than enteral nutrition.

Nutritional approach in malnourished surgical patients: a prospective randomized study

HYPOTHESIS

Perioperative administration of a supplemented enteral formula may decrease postoperative morbidity.

DESIGN

Randomized clinical trial.

SETTING

Department of surgery at a university hospital.

PATIENTS

One hundred ninety-six registered malnourished patients (weight loss > or = 10%) who were candidates for major elective surgery for malignancy of the gastrointestinal tract.

INTERVENTION

After randomization (n = 150), one group received postoperative enteral feeding with a standard diet within 12 hours of surgery (control group; n = 50). Another group orally received 1 L/d for 7 consecutive days of a liquid diet enriched with arginine, omega-3 fatty acids, and RNA (preoperative group; n = 50). After surgery, patients were given the same standard enteral formula as the control group. A third group orally received 1 L/d for 7 consecutive days of the enriched liquid diet. After surgery, patients were given enteral feeding with the same enriched formula (perioperative group; n = 50).

MAIN OUTCOME MEASURES

Postoperative complications and length of hospital stay.

RESULTS

The 3 groups were comparable for baseline demographics, biochemical markers, comorbidity factors, and surgical variables. The intent-to-treat analysis showed that the total number of patients with complications was 24 in the control group, 14 in the preoperative group, and 9 in the perioperative group (P =.02, control group vs perioperative group). Postoperative length of stay was significantly shorter in the preoperative (13.2 days) and perioperative (12.0 days) groups than in the control group (15.3 days) (P =.01 and P =.001, respectively, vs the control group).

CONCLUSION

Perioperative immunonutrition seems to be the best approach to support malnourished patients with cancer.

The process of microbial translocation

The process of microbial translocation was studied using Candida albicans, Escherichia coli, or endotoxin instilled into Thiry-Vella loops of thermally injured guinea pigs and rats. Translocation of C. albicans occurred by direct penetration of enterocytes by a unique process different from classical phagocytosis. Translocation between enterocytes was not observed. Internalization was associated with a disturbance of the plasma membrane and brush border, but most internalized organisms were not surrounded by a plasma membrane. Passage of the candida into the lamina propria appeared to be associated with disruption of the basal membrane with extrusion of cytoplasm of the cell and candida. Organisms in the lamina propria were commonly phagocytized by macrophages but also were found free in lymphatics and blood vessels. Translocation of E. coli and endotoxin also occurred directly through enterocytes rather than between them, but translocated endotoxin diffused through the lamina propria and muscular wall of the bowel wall by passing between rather than through the myocytes. These descriptive phenomena provide new insight into the role of the enterocyte and intestinal immune cells in the translocation process.

Preoperative oral arginine and n-3 fatty acid supplementation improves the immunometabolic host response and outcome after colorectal resection for cancer

BACKGROUND

Previous trials showed that perioperative immunonutrition improved outcome in patients with gastrointestinal cancer. This study was designed to appraise the impact of the simple preoperative oral arginine and n-3 fatty acids supplementation on immune response, gut oxygenation, and postoperative infections.

METHODS

Two hundred patients with colorectal neoplasm were randomized to: (a) oral intake for 5 days before surgery of a formula enriched with arginine and n-3 fatty acids (pre-op group; n = 50); (b) same preoperative treatment prolonged after surgery by jejunal infusion (peri-op group; n = 50); (c) oral intake for 5 days before surgery of a standard isoenergetic, isonitrogenous formula (control group; n = 50); and (d) no supplementation before and after operation (conventional group; n = 50). The immune response was measured by phagocytosis ability of polymorphonuclear cells and delayed hypersensitivity response to skin tests. Gut oxygenation and microperfusion were assessed by polarographic probes and laser Doppler flowmetry, respectively.

RESULTS

The 4 groups were comparable for demographics, comorbidity, and surgical variables. The 2 groups receiving immunoutrients (pre-op and peri-op) had a significantly better immune response, gut oxygenation, and microperfusion than the other 2 groups. Intent-to-treat analysis showed an overall infection rate of 12% in pre-op, 10% in peri-op, 32% in control, and 30% in conventional groups (P <.04 pre-op and peri-op vs control and conventional).

CONCLUSION

Preoperative oral arginine and n-fatty acids improves the immunometabolic response and decreases the infection rate. Postoperative prolongation with such supplemented formula has no additional benefit.

Postoperative complications in gastrointestinal cancer patients: the joint role of the nutritional status and the nutritional support

BACKGROUND & AIMS

This study investigated the effects of nutritional support on postoperative complications, in relation with demographic and nutritional factors, intraoperative factors, type and routes of nutritional regimens.

METHODS

A series of 1410 subjects underwent major abdominal surgery for gastrointestinal cancer and received various types of nutritional support: standard intravenous fluids (SIF; n=149), total parenteral nutrition (TPN; n=368), enteral nutrition (EN; n=393), and immune-enhancing enteral nutrition (IEEN; n=500). Postoperative complications, considered as major (if lethal or requiring re-operation, or transfer to intensive care unit), or otherwise minor, were recorded.

RESULTS

Major and minor complications occurred in 101 (7.2%) and 446 (31.6%) patients, respectively. Factors correlated with postoperative complications at multivariate analysis were pancreatic surgery, (p<0.001), advanced age (p=0.002), weight loss (p=0.019), low serum albumin (p=0.019) and nutritional support (p=0.001). Nutritional support reduced morbidity versus SIF with an increasing protective effect of TPN, EN, and IEEN. This effect remained valid regardless the severity of risk factors identified at the multivariate analysis and it was more evident by considering infectious complications only.

CONCLUSIONS

Pancreatic surgery, advanced age, weight loss and low serum albumin are independent risk factors for the onset of postoperative complications. Nutritional support, particularly IEEN, significantly reduced postoperative morbidity.

Perioperative immunonutrition in patients undergoing cancer surgery: results of a randomized double-blind phase 3 trial

HYPOTHESIS

Perioperative administration of a supplemented enteral formula may reduce the rate of postoperative infections.

DESIGN

Prospective, randomized, double-blind clinical trial.

SETTING

Department of surgery at a university hospital.

PATIENTS

Two hundred six patients with neoplasm of colorectum, stomach, or pancreas.

INTERVENTION

Patients were randomized to drink 1 L/d of either a control enteral formula (n = 104) or the same formula enriched with arginine, RNA, and omega3 fatty acids (n = 102) for 7 consecutive days before surgery. The 2 diets were isoenergetic and isonitrogenous. Jejunal infusion with the same formulas was started 6 hours after operation and continued until postoperative day 7.

MAIN OUTCOME MEASURES

Rate of postoperative infectious complications and length of hospital stay.

RESULTS

Both groups were comparable for age, sex, weight loss, Karnofsky scale score, nutritional status, hemoglobin level, duration of surgery, blood loss, and rate of homologous transfusion. Intent-to-treat analysis showed a 14% (14/102) infectious complication rate in the supplemented group vs 30% (31/104) in the control group (P = .009). In the eligible population, the postoperative infection rate was 11% (9/85) in the supplemented group vs. 24% (21/86) in the control group (P = .02). The mean +/- SD length of postoperative stay was 11.1+/-4.4 days in the supplemented group and 12.9+/-4.6 in the control group (P = .01).

CONCLUSION

Perioperative administration of a supplemented enteral formula significantly reduced postoperative infections and length of stay in patients undergoing surgery for cancer.

Altered microperfusion at the rectal stump is predictive for rectal anastomotic leak

PURPOSE

The aim of this study was to evaluate the reliability of intraoperative laser-Doppler measurements in predicting the occurrence of anastomotic leak in patients with colorectal cancer undergoing stapled straight anastomosis to the rectum.

METHODS

A prospective study was undertaken on 55 patients with rectal cancer or distal sigmoid cancer programmed for elective curative surgery. In all patients transmural colonic blood flow was measured by laser-Doppler flowmetry technique before bowel manipulation (baseline measurement) and after vascular ligation and division. Comorbidities at admission, intraoperative events, associated surgical procedures, and clinical outcome were tested for any association with anastomotic leak.

RESULTS

Postoperative mortality was 1.8 percent (1/55 patients), and the overall morbidity was 21.3 percent. Anastomotic leak occurred in eight patients (14.5 percent). After colonic division a blood flow reduction at the rectal stump was observed in 42 patients (76.3 percent) as compared with baseline measurement. The mean rectal stump flow reduction was 6.2 percent in patients without anastomotic leak, whereas in patients who developed anastomosis breakdown it was 16 percent (P < 0.001). Mean proximal stump flow reduction was 5.1 percent in the uncomplicated patients, whereas in patients who had an anastomosis breakdown it was 12.9 percent (P < 0.01). A positive linear correlation was found between decrease in blood flow and rate of anastomotic leak.

CONCLUSION

Blood flow reduction at the rectal stump is associated with an increased risk of anastomotic leak.

Early postoperative enteral nutrition improves gut oxygenation and reduces costs compared with total parenteral nutrition

OBJECTIVE

To evaluate the potential clinical, metabolic, and economic advantages of enteral nutrition over total parenteral nutrition.

DESIGN

Prospective, randomized clinical trial.

SETTING

Department of surgery in a university hospital.

PATIENTS

Two hundred and fifty-seven patients with cancer of the stomach (n = 121), pancreas (n = 110), or esophagus (n = 26) were randomized to receive postoperative total parenteral nutrition (TPN group, n = 131) or early enteral nutrition (EEN group, n = 126). The nutritional goal was 25 kcal/kg/day. The two nutritional formulas were isocaloric and isonitrogenous, and they were continued until oral intake was at least 800 kcal/day.

MEASUREMENTS

Morbidity, mortality, length of hospital stay, and treatment costs were evaluated in all patients. In 40 consecutive patients, selected nutritional, immunologic and inflammatory variables were studied. Moreover, intestinal oxygen tension was evaluated by micropolarographic implantable probes.

MAIN RESULTS

The nutritional goal was reached in 100/126 (79.3%) patients in the EEN group and in 128/131 (97.7%) patients in the TPN group (p <.001). In the EEN group, hyperglycemia (serum glucose, >200 mg/dL) was observed in 4.7% of the patients vs. 9.1% in the TPN group (p = NS). Alteration of serum electrolyte levels was 3.9% in the EEN group vs. 13.7% in the TPN group (p <.01). No significant difference was found in nutritional, immunologic, and inflammatory variables between the two groups. The overall complication rate was similar (40.4% for TPN vs. 35.7%, for EEN; p =.52). No difference was detected for either infectious or noninfectious complications, length of hospital stay, and mortality. From postoperative day 5, intestinal oxygen tension recovered faster in the EEN group than in the TPN group (43 +/- 5 mm Hg vs. 31 +/- 4 mm Hg at day 7; p <.001). EEN was four-fold less expensive than TPN ($25 vs. $90.60/day, respectively).

CONCLUSION

EEN represents a rational alternative to TPN in patients who undergo upper gastrointestinal tract surgery for cancer and who clinically require postoperative artificial nutrition.

New approach to the diagnosis of growth hormone deficiency in adults

Pyridostigmine (PD), a muscarinic cholinergic agonist, and arginine (ARG) clearly increase the growth hormone (GH) response to growth hormone-releasing hormone (GHRH) in man. The current study was undertaken to investigate the value and safety of PD + GHRH and ARG + GHRH tests as well as the measurement of serum insulin-like growth factor I (IGF-I) in diagnosing GH deficiency in adults. Fifty-four patients considered GH deficient from extensive organic or idiopathic pituitary disease and 326 healthy adults were studied. The IGF-I concentrations were lower than the 3rd percentile of normal values in only 31 of the 54 (57.4%) patients with hypopituitarism. However, the IGF-I levels in hypopituitary patients and in normal subjects overlapped more frequently between 41 and 60 years (50%) and between 61 and 80 years (92.3%) as opposed to between 20 and 40 years (8.6%). In contrast to the IGF-I measurement, the ranges of peak GH responses to PD + GHRH and ARG + GHRH tests were clearly differentiated between the hypopituitary (0.2-6.8 and 0.1-9.5 microg/l, respectively) and normal (17.7-114 and 16.1-119 microg/l, respectively). However, the PD + GHRH test was reliable only in subjects of 20-40 years of age. In conclusion, IGF-I measurement had no value in the diagnosis of GH deficiency in adults aged over 40 years, but is reliable enough when young adults of 20-40 years of age are considered. Both PD + GHRH and ARG + GHRH testing should be considered more reliable biochemical measurements of GH deficiency. In contrast to the PD + GHRH test, the ARG + GHRH test is reliable throughout the adult lifespan and appears to be the most appropriate for patient compliance and safety.

Nutritional support and therapy in pancreatic surgery: A position paper of the International Study Group on Pancreatic Surgery (ISGPS)

BACKGROUND

The optimal nutritional therapy in the field of pancreatic surgery is still debated.

METHODS

An international panel of recognized pancreatic surgeons and pancreatologists decided that the topic of nutritional support was of importance in pancreatic surgery. Thus, they reviewed the best contemporary literature and worked to develop a position paper to provide evidence supporting the integration of appropriate nutritional support into the overall management of patients undergoing pancreatic resection. Strength of recommendation and quality of evidence were based on the approach of the grading of recommendations assessment, development and evaluation Working Group.

RESULTS

The measurement of nutritional status should be part of routine preoperative assessment because malnutrition is a recognized risk factor for surgery-related complications. In addition to patient's weight loss and body mass index, measurement of sarcopenia and sarcopenic obesity should be considered in the preoperative evaluation because they are strong predictors of poor short-term and long-term outcomes. The available data do not show any definitive nutritional advantages for one specific type of gastrointestinal reconstruction technique after pancreatoduodenectomy over the others. Postoperative early resumption of oral intake is safe and should be encouraged within enhanced recovery protocols, but in the case of severe postoperative complications or poor tolerance of oral food after the operation, supplementary artificial nutrition should be started at once. At present, there is not enough evidence to show the benefit of avoiding oral intake in clinically stable patients who are complicated by a clinically irrelevant postoperative pancreatic fistula (a so-called biochemical leak), while special caution should be given to feeding patients with clinically relevant postoperative pancreatic fistula orally. When an artificial nutritional support is needed, enteral nutrition is preferred whenever possible over parenteral nutrition. After the operation, regardless of the type of pancreatic resection or technique of reconstruction, patients should be monitored carefully to assess for the presence of endocrine and exocrine pancreatic insufficiency. Although fecal elastase-1 is the most readily available clinical test for detection of pancreatic exocrine insufficiency, its sensitivity and specificity are low. Pancreatic enzyme replacement therapy should be initiated routinely after pancreatoduodenectomy and in patients with locally advanced disease and continued for at least 6 months after surgery, because untreated pancreatic exocrine insufficiency may result in severe nutritional derangement.

CONCLUSION

The importance of this position paper is the consensus reached on the topic. Concentrating on nutritional support and therapy is of utmost value in pancreatic surgery for both short- and long-term outcomes.

Oral glutamine decreases bacterial translocation and improves survival in experimental gut-origin sepsis

BACKGROUND

Glutamine has been shown to be an important dietary component for the maintenance of gut metabolism. The purpose of this study was to assess the potential benefit of glutamine-enriched diets on experimental gut-derived sepsis.

METHODS

BALB/c mice were fed either 2% glutamine-supplemented or 1% glycine-supplemented (near-isonitrogenous control) AIN-76A diets. Control mice received either nonsupplemented AIN-76A or regular Purina Rodent Laboratory Mouse Chow 5001 diets. After 10 days of feeding, the mice were transfused with allogeneic blood (from C3H/HeJ mice), and the feeding protocols were continued for an additional 5 days. The mice then underwent gavage with 10(10) Escherichia coli labeled with either indium-111 oxine or [14C]glucose followed immediately by a 20% burn injury. Some mice were observed 10 days postburn for survival rates. Others were killed 4 hours after burn, and the mesenteric lymph nodes, liver, and spleen were harvested to determine radionuclide and bacterial colony counts. The percentages of viable translocated E coli were also calculated.

RESULTS

Mice fed glutamine-enriched diets had a lower degree of translocation (as measured by both radionuclide and bacterial counts) to the tissues than did the other groups and had an improvement in the ability to kill translocated E coli (as measured by the percentage of viable bacteria). Survival was significantly higher in the group fed 2% glutamine (81%) compared with the groups fed 1% glycine (36%), AIN-76A (35%), and Purina Rodent Laboratory Mouse Chow 5001 (36%) diets (p < .004).

CONCLUSIONS

Glutamine-supplemented enteral diets may exert important benefits in preventing gut-origin sepsis after trauma.

Perioperative nutrition: Recommendations from the ESPEN expert group

BACKGROUND & AIMS

Malnutrition has been recognized as a major risk factor for adverse postoperative outcomes. The ESPEN Symposium on perioperative nutrition was held in Nottingham, UK, on 14-15 October 2018 and the aims of this document were to highlight the scientific basis for the nutritional and metabolic management of surgical patients.

METHODS

This paper represents the opinion of experts in this multidisciplinary field and those of a patient and caregiver, based on current evidence. It highlights the current state of the art.

RESULTS

Surgical patients may present with varying degrees of malnutrition, sarcopenia, cachexia, obesity and myosteatosis. Preoperative optimization can help improve outcomes. Perioperative fluid therapy should aim at keeping the patient in as near zero fluid and electrolyte balance as possible. Similarly, glycemic control is especially important in those patients with poorly controlled diabetes, with a stepwise increase in the risk of infectious complications and mortality per increasing HbA1c. Immobilization can induce a decline in basal energy expenditure, reduced insulin sensitivity, anabolic resistance to protein nutrition and muscle strength, all of which impair clinical outcomes. There is a role for pharmaconutrition, pre-, pro- and syn-biotics, with the evidence being stronger in those undergoing surgery for gastrointestinal cancer.

CONCLUSIONS

Nutritional assessment of the surgical patient together with the appropriate interventions to restore the energy deficit, avoid weight loss, preserve the gut microbiome and improve functional performance are all necessary components of the nutritional, metabolic and functional conditioning of the surgical patient.

ESPEN guideline on clinical nutrition in acute and chronic pancreatitis

Both acute and chronic pancreatitis are frequent diseases of the pancreas, which, despite being of benign nature, are related to a significant risk of malnutrition and may require nutritional support. Acute necrotizing pancreatitis is encountered in 20% of patients with acute pancreatitis, is associated with increased morbidity and mortality, and may require artificial nutrition by enteral or parenteral route, as well as additional endoscopic, radiological or surgical interventions. Chronic pancreatitis represents a chronic inflammation of the pancreatic gland with development of fibrosis. Abdominal pain leading to decreased oral intake, as well as exocrine and endocrine failure are frequent complications of the disease. All of the above represent risk factors related to malnutrition. Therefore, patients with chronic pancreatitis should be considered at risk, screened and supplemented accordingly. Moreover, osteoporosis and increased facture risk should be acknowledged in patients with chronic pancreatitis, and preventive measures should be considered.

Effect of route of delivery and formulation of postoperative nutritional support in patients undergoing major operations for malignant neoplasms

OBJECTIVE

To study the effect of the route of delivery and formulation of postoperative nutritional support on host defense, protein metabolism, infectious complications, and outcome.

DESIGN

Prospective, randomized, clinical trial.

SETTING

Department of Surgery at a university hospital.

PATIENTS

Two hundred sixty candidates for pancreaticoduodenectomy or gastrectomy for cancer.

INTERVENTIONS

Patients were randomly allocated into 3 groups during surgery. Starting 6 hours after operation, the first group received a standard enteral formula (standard group; n = 87); the second, the same enteral formula enriched with arginine, omega-3 fatty acids, and RNA (immunonutrition group; n = 87); and the third, total parenteral nutrition (parenteral group; n = 86). The 3 regimens were isocaloric and isonitrogenous. The nutritional goal was 105 kJ/kg per day.

MAIN OUTCOME MEASURES

Immune response by phagocytosis ability of polymorphonuclear cells, interleukin (IL)-2 receptor levels, and delayed hypersensitivity response; protein synthesis by IL-6 and prealbumin; tolerance of enteral feeding; incidence of postoperative complications; and length of hospital stay.

RESULTS

The immunonutrition group had a significantly better recovery of the immune parameters on postoperative day 8 compared with the other groups. Linear regression analysis showed an inverse correlation between IL-6 and preambulin levels (r = 0.766) only in the immunonutrition group. Only 11 patients (6.3%) in both enteral groups did not reach the nutritional goal. Postoperative infection rate was 14.9% (13/87) in the immunonutrition group, 22.9% (20/87) in the standard group, and 27.9% (24/86) in the parenteral group (P = .06). Mean +/- SD length of hospital stay was 16.1 +/- 6.2, 19.2 +/- 7.9, and 21.6 +/- 8.9 days in the immunonutrition, standard, and parenteral groups, respectively (P = .01 vs standard group; P = .004 vs parenteral group).

CONCLUSIONS

Early postoperative enteral feeding is a valid alternative to parenteral feeding in patients undergoing major surgery. Immunonutrition enhances the host response, induces a switch from acute-phase to constitutive proteins, and improves outcome.

Laparoscopic versus open colorectal surgery: a randomized trial on short-term outcome

OBJECTIVE

The primary endpoint was to compare the impact of laparoscopic and open colorectal surgery on 30-day postoperative morbidity. Lymphocyte proliferation to mitogens and gut oxygen tension were surrogate endpoints.

SUMMARY BACKGROUND DATA

Evidence-based proof of the effect of laparoscopic colorectal surgery on immunometabolic response and clinically relevant outcome variables is scanty. Further randomized trials are desirable before proposing laparoscopy as a superior technique.

METHODS

Two hundred sixty-nine patients with colorectal disease were randomly assigned to laparoscopic (n = 136) or open (n = 133) colorectal resection. Four trained members of the surgical staff who were not involved in the study registered postoperative complications. Lymphocyte proliferation to Candida albicans and phytohemagglutinin was evaluated before and 3 and 15 days after surgery. Operative gut oxygen tension was monitored continuously by a polarographic microprobe.

RESULTS

In the laparoscopic group the conversion rate was 5.1%. The overall morbidity rate was 20.6% in the laparoscopic group and 38.3% in the open group. Postoperative infections occurred in 15 of the 136 patients in the laparoscopic group and 31 of the 133 patients in the open group. The mean length of hospital stay was 10.4 +/- 2.9 days in the laparoscopic group and 12.5 +/- 4.1 days in the open group. On postoperative day 3, lymphocyte proliferation was impaired in both groups. Fifteen days after surgery, the proliferation index returned to baseline values only in the laparoscopic group. Intraoperative gut oxygen tension was higher in the laparoscopic than in the open group.

CONCLUSIONS

Laparoscopic colorectal surgery resulted in a significant reduction of 30-day postoperative morbidity. Lymphocyte proliferation and gut oxygen tension were better preserved in the laparoscopic group than in the open group.

Arginine-supplemented diets improve survival in gut-derived sepsis and peritonitis by modulating bacterial clearance. The role of nitric oxide

OBJECTIVE

The effect of arginine on survival rates and host defense mechanisms was studied using two clinically relevant models of infection that included transfusion-induced immunosuppression.

SUMMARY BACKGROUND DATA

Dietary arginine will improve resistance to infection but its role in transfusion-induced immunosuppression and bacterial translocation (gut-derived sepsis) has not been defined.

METHODS

Balb/c mice were fed for 10 days with either a defined AIN-76A diet, an AIN-76A diet supplemented with 2% arginine, an AIN-76A diet supplemented with 4% glycine, or standard laboratory chow. In most experiments, the mice were then transfused with allogeneic blood and allowed to feed for an additional 5 days before undergoing either cecal ligation and puncture (CLP) or gavage with 10(10) Escherichia coli and a 20% burn injury. Additional animals fed with the arginine supplemented diet were treated with the nitric oxide inhibitor N omega-Nitro-L-arginine (NNA) before gavage and burn. The effect of these diets and NNA on the degree of translocation of 14C-radiolabeled E. coli from the intestine and the ability of the host to kill translocated organisms was also investigated. Mice were fed and received transfusion, gavage, and burn as above. Mesenteric lymph nodes (MLN), liver and spleen were harvested 4 hours postburn.

RESULTS

Survival after CLP was 56% in the arginine-supplemented group versus 28% in the AIN-76A group and 20% in the chow group (p < 0.02). After gavage and burn, survival was 100% in the arginine-supplemented group versus 50% in both the glycine-supplemented and chow groups and 35% in the AIN-76A group (p < 0.01). In animals receiving the arginine-supplemented diet, treatment with NNA decreased survival from 95% to 30.5% (p < 0.0001). Greater translocation, as measured by radionuclide counts, was observed to the MLN of the AIN-76A group. However, there was no difference in translocation to the liver and spleen related to dietary group. Quantitative colony counts and the calculated percentage of remaining viable bacteria showed that the ability to kill translocated organisms was significantly enhanced in animals receiving arginine. Treatment with NNA reversed the beneficial effects of arginine on immune defense.

CONCLUSIONS

The benefit of arginine appears to be mediated by improved bactericidal mechanisms via the arginine-nitric oxide pathway.

A randomized double-blind trial on perioperative administration of probiotics in colorectal cancer patients

AIM: To investigate whether probiotic bacteria, given perioperatively, might adhere to the colonic mucosa, reduce concentration of pathogens in stools, and modulate the local immune function.

METHODS: A randomized, double-blind clinical trial was carried out in 31 subjects undergoing elective colorectal resection for cancer. Patients were allocated to receive either a placebo (group A, n = 10), or a dose of 10⁷ of a mixture of Bifidobacterium longum (BB536) and Lactobacillus johnsonii (La1) (group B, n = 11), or the same mixture at a concentration of 10⁹ (group C, n = 10). Probiotics, or a placebo, were given orally 2 doses/d for 3 d before operation. The same treatment continued postoperatively from day two to day four. Stools were collected before treatment, during surgery (day 0) and 5 d after operation. During the operation, colonic mucosa samples were harvested to evaluate bacterial adherence and to assess the phenotype of dendritic cells (DCs) and lymphocyte subsets by surface antigen expression (flow cytometry). The presence of BB536 and La1 was evaluated by the random amplified polymorphism DNA method with specific polymerase chain reaction probes.

RESULTS: The three groups were balanced for baseline and surgical parameters. BB536 was never found at any time-points studied. At day 0, La1 was present in 6/10 (60%) patients in either stools or by biopsy in group C, in 3/11 (27.2%) in group B, and none in the placebo group (P = 0.02, C vs A). There was a linear correlation between dose given and number of adherent La1 (P = 0.01). The rate of mucosal colonization by enterobacteriacae was 30% (3/10) in C, 81.8% (9/11) in B and 70% (7/10) in A (P = 0.03, C vs B). The Enterobacteriacae count in stools was 2.4 (log10 scale) in C, 4.6 in B, and 4.5 in A (P = 0.07, C vs A and B). The same trend was observed for colonizing enterococci. La1 was not found at day +5. We observed greater expression of CD3, CD4, CD8, and naive and memory lymphocyte subsets in group C than in group A with a dose response trend (C > B > A). Treatment didnot affect DC phenotype or activation, but after ex vivo stimulation with lipopolysaccharides, groups C and B had a lower proliferation rate compared to group A (P = 0.04). Moreover, dendritic phenotypes CD83-123, CD83-HLADR, and CD83-11c (markers of activation) were significantly less expressed in patients colonized with La1 (P = 0.03 vs not colonized).

CONCLUSION: La1, but not BB536, adheres to the colonic mucosa, and affects intestinal microbiota by reducing the concentration of pathogens and modulates local immunity.

Artificial nutrition after major abdominal surgery: impact of route of administration and composition of the diet

OBJECTIVE

To evaluate the impact of the route of administration of artificial nutrition and the composition of the diet on outcome.

DESIGN

Prospective, randomized, clinical trial.

SETTING

Department of surgery, university hospital.

PATIENTS

One hundred sixty-six consecutive patients undergoing curative surgery for gastric or pancreatic cancer.

INTERVENTIONS

At operation, the patients were randomized into three groups to receive: a) a standard enteral formula (control group; n = 55); b) the same enteral formula enriched with arginine, RNA, and omega-3 fatty acids (enriched group; n = 55); and c) total parenteral nutrition (TPN group; n = 56). The three regimens were isocaloric and isonitrogenous. Enteral nutrition was started within 12 hrs following surgery. The infusion rate was progressively increased to reach the nutritional goal (25 kcal/kg/day) on postoperative day 4.

MEASUREMENTS AND MAIN RESULTS

Tolerance of enteral feeding, rate and severity of postoperative complications, and length of hospital stay were recorded. Early enteral infusion was well tolerated. Side effects were recorded in 22.7% of the patients, but only 6.3% did not reach the nutritional goal. The enriched group had a lower severity of infection than the parenteral group (4.0 vs. 8.6; p < .05). In subgroups of malnourished (n = 78) and homologous transfused patients (n = 42), the administration of the enriched formula significantly reduced both severity of infection and length of stay compared with the parenteral group (p < .05). Moreover, in transfused patients, the rate of septic complications was 20.0% in the enriched group, 38.4% in the control group, and 42.8% in the TPN group.

CONCLUSIONS

Early enteral feeding is a suitable alternative to TPN after major abdominal surgery. The use of the enriched diet appears to be more beneficial in malnourished and transfused patients.

Increased interleukin-10 serum levels in patients with solid tumours

In 40 out of 99 patients (40.4%) with solid tumours of different tissue, but the same stage (IV), elevated serum levels of interleukin-10 were observed. The mean levels of the cytokine in patients with malignant melanoma (24.3 ng/ml), pancreatic (6.8 ng/ml) or gastric (6.3 ng/ml) adenocarcinoma were significantly higher than in healthy subjects (3.4 ng/ml) or in patients with uterine fibroma (1.7 ng/ml). Patients with colon (6.8 ng/ml) and renal (5.7 ng/ml) carcinoma had similar values of interleukin-10 but did not significantly differ from controls. Interleukin-10 is known to suppress the functions of both T lymphocytes and macrophages, working as a general dampener of the immune and inflammatory responses. The observation of increased circulating levels of interleukin-10 in cancer patients may have important implications for future investigations, immunological monitoring and therapeutic intervention on neoplastic patients, and suggests a mechanism for tumour cells escaping from immune surveillance.

A prospective, randomized clinical trial on perioperative feeding with an arginine-, omega-3 fatty acid-, and RNA-enriched enteral diet: effect on host response and nutritional status

BACKGROUND

The use of immune-enhancing enteral diets in the postoperative period has given contrasting results. The purpose of this prospective, randomized, double-blinded clinical study was to evaluate the effect of immunonutrition given perioperatively on cytokine release and nutritional parameters.

METHODS

Patients with cancer of the stomach or colo-rectum were eligible. Subjects consumed 1 L/d of either a control enteral formula (n = 25; control group) or a formula supplemented with arginine, omega-3 fatty acids, and RNA (n = 25; verum group) for 1 week before surgery. Both formulas were given by mouth. Six hours after the operation, jejunal infusion with the same diets was started and maintained for 7 days. Blood was drawn at different time points to assess albumin, prealbumin (PA), transferrin, cholinesterase activity, retinol binding protein (RBP), interleukin-2 receptors alpha (IL-2Ralpha), IL-6, and IL-1 soluble receptors (IL-1RII). The composite score of delayed hypersensitivity response (DHR) to skin test also was determined (the higher the score, the lower the immune response).

RESULTS

During the 7 days of presurgical feeding, none of the above parameters changed in either group. Eight days after operation, in the control group, the concentration of PA and RBP was lower than in the verum group (0.18 vs 0.26 g/L for PA and 30.5 vs 38.7 mg/L for RBP; p < .05). IL-2Ralpha concentration was 507 pg/mL in the verum group vs 238 pg/mL in the control group (p < .001), whereas IL-6 and IL-1RII were higher in the control group than in the verum group (104 vs 49 and 328 vs 183 pg/mL, respectively; p < .01). The DHR score was 0.68 in the control group vs 0.42 in the verum group (p < .05).

CONCLUSIONS

Perioperative feeding with a supplemented enteral diet modulates cytokine production and enhances cell-mediated immunity and the synthesis of short half-life proteins.

Metabolic and functional results after laparoscopic colorectal surgery: a randomized, controlled trial

PURPOSE

This study was designed to compare metabolic and functional results after laparoscopic and open colorectal resection.

METHODS

Seventy-nine patients were randomly assigned to laparoscopic (n = 40) or open (n = 39) colorectal resection. Before and after operation, the following parameters were determined: respiratory function (spirography and blood gas); serum level of cortisol, lactate, and C-reactive protein; total lymphocyte count; and CD4 and CD8 lymphocyte subsets. Intraoperative core temperature was measured by a bladder probe. Postoperative pain and analgesic consumption were also monitored.

RESULTS

Mild operative hypothermia, a trend to postoperative reduction of total lymphocyte count, and significant impairment of respiratory function early after surgery were found in both groups. Laparoscopy showed a higher CD4/CD8 ratio (P = 0.01) on postoperative Day 1 and a faster return of C-reactive protein to preoperative values (P = 0.01) than in the open colorectal resection group. Morphine consumption in the first 48 hours after surgery was lower in the laparoscopic than in the open group (P = 0.02).

CONCLUSIONS

Laparoscopy was associated with a less pronounced immunosuppression and inflammatory response and a lower consumption of analgesic drugs than open surgery. Moreover, our data did not show any additional detrimental effect of laparoscopy on either operative core temperature or early postoperative respiratory function.

Role of early enteral feeding and acute starvation on postburn bacterial translocation and host defense: prospective, randomized trials

OBJECTIVES

To investigate the effect of: a) starvation during the preburn period and b) immediate postburn enteral nutrition on the permeability of the gut to microorganisms and the ability of the host to kill translocated bacteria.

DESIGN

Prospective, randomized, experimental trials.

SETTING

Laboratory.

SUBJECTS

Balb/c mice and Hartley guinea pigs.

INTERVENTIONS

In the first experiment, mice were starved for 0, 6, 12, 18, or 24 hrs before receiving gavage with 10(10) 14C-labeled Escherichia coli and a 20% burn injury. In the second experiment, guinea pigs received a 40% burn injury and were randomized to receive a complete enteral diet (175 kcal/kg/day) or infusion of an equal volume of lactated Ringer's solution via a previously placed gastrostomy for 6, 24, or 48 hrs. After each feeding period, 10(10) 14C Escherichia coli were infused intragastrically. In both experiments, the animals were killed 4 hrs after gavage, and mesenteric lymph nodes, spleen, liver, lungs, peritoneal fluid, and blood were harvested aseptically.

MEASUREMENTS

For each tissue or fluid, the number of viable E. coli and radionuclide counts of the 14C E. coli were measured and the percentage of translocated bacteria that remained alive was calculated.

MAIN RESULTS

In mice, 18 and 24 hrs of preburn starvation increased translocation only to the mesenteric lymph nodes, but it also enhanced bacterial killing in all tested tissues. Guinea pigs that were fed enterally for 6, 24, and 48 hrs postburn had significantly lower bacterial translocation in all tissues compared with animals infused with lactated Ringer's solution. Additionally, enhanced killing of translocating organisms was observed after 24 and 48 hrs of feeding.

CONCLUSIONS

Starvation preburn has different consequences than starvation postburn on translocation and bacterial killing. Postburn enteral nutrition decreases the load of viable bacteria in the tissues via a double mechanism: an initial decreased translocation and a subsequent improved ability to kill bacteria that do translocate.

Feeding the gut early after digestive surgery: results of a nine-year experience

BACKGROUND AND AIMS

Early enteral nutrition (EEN) after surgery should be preferred to parenteral feeding, but its clinical use is limited for concerns about possible gastrointestinal (GI) adverse effects and feeding tube-related complications. Thus we evaluated our experience focusing on safety and tolerance of early postoperative jejunal feeding and possible risk factors for gastrointestinal adverse effects.

METHODS

650 subjects treated with EEN after major digestive surgery for cancer were prospectively studied. EEN was started within 12 hours after operation via a naso-jejunal (NJ) feeding tube or a catheter-feeding jejunostomy. The rate of infusion was progressively increased to reach the nutritional goal (25 kcal/kg/day) within the 4th postoperative day. Rigorous treatment protocols for diet delivery and EEN-related GI adverse effects were applied.

RESULTS

402 patients had a jejunostomy and 248 patients a NJ tube. EEN-related GI adverse effects were observed in 194/650 patients (29.8%). In 136/194 patients, these events were successfully handled by treatment protocols. Overall the nutritional goal was achieved in 592/650 patients (91.1%). Fifty-eight (8.9%) subjects had to be switched to parenteral feeding because of refractory intolerance to EEN. Intra-abdominal surgical complications and low serum albumin (<30 g/L) were the two major factors affecting tolerance. Severe jejunostomy-related complications occurred in 7/402 (1.7%) patients. EEN-related mortality was 0.1% (1/650).

CONCLUSIONS

The use of the gut early after surgery is safe and well-tolerated and it should represent the first choice for nutritional support in this type of patients.