[Incidental finding of an intestinally differentiated adenocarcinoma in a tailgut cyst after robotic-assisted resection]. / Zufallsbefund eines intestinal differenzierten Adenokarzinoms in einer Tailgut Zyste nach robotisch-assistierter Resektion.

Due to pelvic symptoms, a diagnostic sectional imaging was initiated in a 52-year-old female patient. This revealed a cystic, retrorectal mass, suspected to be a tailgut cyst. Due to the symptoms and the unclear dignity after several frustrating endosonographic punctures, a robotic-assisted resection of the cystic Tumor was performed after careful interdisciplinary consultation.The histological examination confirmed the diagnosis of a tailgut cyst but also revealed parts of an intestinally differentiated adenocarcinoma.Due to the unclear metastatic behaviour, robotic-assisted low anterior resection with total mesorectal excision was performed as oncological resection, similar to rectal carcinomas. No residuals or lymph node metastases were detectable in the histological examination, so that follow- up monitoring was recommended.Retrorectal tumours are an extremely rare entity, worldwide only 28 cases of an intestinally differentiated carcinoma in a tailgut cyst have been described so far. Since there are no clear recommendations in the literature regarding the diagnostic or therapeutic procedure, we would like to discuss a possible algorithm in case of a proven retrorectal mass in our case study.

Safety and Suitability of the SmartPill® after Abdominal Surgery: Results of the Prospective, Two-Armed, Open-Label PIDuSA Trial.

INTRODUCTION: Postoperative ileus (POI) is a common complication after abdominal surgery. Until today, an evidence-based treatment of prolonged POI is still lacking, which can be attributed to the poor quality of clinical trials. Various different surrogate markers used to define POI severity are considered to be the cause of low-quality trials making it impossible to derive treatment recommendation. The SmartPill®, which is able to record pH values, temperature and pressure after ingestion, could be an ideal tool to measure transit times and peristalsis and therefore analyze POI severity. Unfortunately, the device has no approval for postoperative use due to safety concerns. The primary objective of the study is to determine safety of the SmartPill® in patients undergoing surgery. Secondary objectives were the quality of the recorded data and the suitability of the SmartPill® for analyzing intestinal motility after different surgical procedures. METHODS: The PIDuSA Study is a prospective, 2-arm, open-label trial. At the end of surgery, the SmartPill® was applied to 49 patients undergoing abdominal surgery having a high risk for impaired intestinal motility and 15 patients undergoing extra-abdominal surgery. Patients were visited daily to access safety data of the SmartPill® on the basis of adverse and serious adverse events (AEs/SAEs). Suitability and data quality were investigated by analyzing data completeness and feasibility to determine transit times and peristalsis for all sections of the gastrointestinal tract. RESULTS: In total, 179 AEs and 8 SAEs were recorded throughout the study affecting 42 patients in the abdominal (158 AEs) and 9 patients in the extra-abdominal surgery group (21 AEs, p = 0.061); none of them were device related. Primary capsule failure was observed in 5 patients, ultimately resulting in an impossibility of data analysis in only 3 patients (4.4%). 9% of the recorded data were incomplete due to the patient's incompliance in keeping the receiver close to the body. In 3 patients (4.4%), isolated small bowel transit could not be determined due to pH alterations as a result of prolonged POI. DISCUSSION: Our study demonstrates that the use of the SmartPill® is safe after surgery but requires a reasonable patient compliance to deliver meaningful data. An objective analysis of transit times and peristalsis was possible irrespective of type and site of surgery in over 95% indicating that the SmartPill® has the potential to deliver objective parameters for POI severity in future clinical trials. However, in some patients with prolonged POI, analysis of small bowel transit could be challenging.

[Treatment of HPV-associated Anal Lesions in HIV-positive Patients - Comparison of Surgical Treatment and Topical Therapy with Imiquimod]. / Behandlung HPV-assoziierter analer Läsionen bei HIV-positiven Patienten ­ chirurgische Abtragung vs. topische Therapie mit Imiquimod.

OBJECTIVES: In HIV+-patients, routine proctological assessment is warranted due to the high incidence of human papilloma virus (HPV) infection-related anogenital lesions, such as Condylomata acuminata (C. ac.), anal intraepithelial dysplasia (AIN) and anal cancer. For C. ac. and AIN, surgical resection and topical therapy with imiquimod have been discussed as treatment options. BACKGROUND: In this study, we contrasted surgical resection and topical imiquimod therapy of HPV-associated anal lesions in HIV+-patients, with a focus on healing rates and clinical outcome. We also analysed whether a synergistic treatment effect was detectable. METHODS: This was a retrospective analysis of 97 HIV+ patients who underwent proctological evaluation and treatment over a 10-year period (11/2004 - 11/2015) at our centre. Initial success of surgical treatment, topical imiquimod therapy and the combination of the two strategies were compared. RESULTS: In 53/97 patients (54%), HPV-associated anal disease was diagnosed upon the first visit. In approx. 50% of the patients, the HIV infection was adequately controlled (52 patients with viral load < 40 copies [53.6%]) under cART. The mean age was 41.0 ± 11.6 years. In 7/53 patients with macroscopic C. ac., low-grade and in 18/53 patients high-grade AIN were additionally confirmed. Success rates of surgical resection, imiquimod treatment and the combination of the two were compared. Complete remission of C. ac. and AIN four weeks after treatment was considered a therapeutic success. For C. ac., success rates with imiquimod were 5/25 (20.0%) vs. surgery* 30/57 (52.6%, Mann-Whitney U test p < 0.05) vs. surgery+imiquimod 7/15 (46.7%). For AIN, success rates with imiquimod were 4/24 (16.7%) vs. surgery* 47/83 (56.7%, Mann-Whitney U test p < 0.05) vs. surgery+imiquimod 9/21 (42.8%). In 7/92 (13%) of surgical treatments, complications were reported: four minor and two significant bleeding episodes and one perianal thrombosis. No side effects of imiquimod were documented besides skin irritation. CONCLUSION: Surgery is more effective than topical imiquimod as initial therapy of HPV-related anogenital disease in HIV+-patients. A synergistic effect could not be demonstrated. On this basis, we recommend surgical treatment of C. ac. and AIN in HIV+-patients as first line treatment.

[Late Complications of Permanent Intestinal Stomata]. / Spätkomplikationen permanenter intestinaler Stomata.

INTRODUCTION: Complications following the creation of permanent intestinal ostomies are common and lead to serious problems in the stoma care of affected patients. The aim of this prospective, single-centre follow-up study was to record the rate of late complications in our own patient group and to identify potential risk factors. METHODS: All patients who received a permanent intestinal ostomy in our clinic within the period 2006 - 2016 were included in the study. 50 patients gave their informed consent and participated in our follow-up (14 female [28%], 36 male [72%]). The analysis of stoma-associated complications was performed by review of medical records and a systematic follow-up (standardised questionnaire, clinical examination, and ultrasound of the abdominal wall). RESULTS: Indications included malignancy (n = 27; 54%), anastomotic leakage (n = 10; 20%), acute diverticulitis (n = 7; 14%), IBD (n = 5; 10%) and rarer indications. The top 3 late complications were peristomal skin irritation (n = 25, 50%), parastomal hernia (n = 14; 28%) and prolapse (n = 9; 18%). Acute diverticulitis resulted in increased stomal retraction (p = 0.012). Double-barreled stomata were associated with increased herniation rates (p = 0.044) and prolapse (p = 0.047). Ileostomies were associated with peristomal skin irritation (p = 0.021). Age, sex or emergency stoma creation did not constitute independent risk factors for the development of late complications in our group of patients. CONCLUSION: Professional pre- and postoperative stoma therapy and care includes preoperative marking of a stoma site and structured stoma-specific follow-up by stoma therapists, surgeons and general practitioners, as well as stringent and early treatment of structural complications. This can prevent and mitigate late complications of permanent intestinal stomata. Interestingly, stoma placement was not an independent risk factor for late complications in an emergency situation.

Intestinal manipulation affects mucosal antimicrobial defense in a mouse model of postoperative ileus.

AIM: To explore the effects of abdominal surgery and interleukin-1 signaling on antimicrobial defense in a model of postoperative ileus. METHODS: C57BL/6 and Interleukin-1 receptor type I (IL-1R1) deficient mice underwent intestinal manipulation to induce POI. Expression of mucosal IL-1α, IL-1ß and IL-1R1 and several antimicrobial peptides and enzymes were measured by quantitative PCR or ELISA, western blotting or immunohistochemistry. Bacterial overgrowth was determined by fluorescent in-situ hybridization and counting of jejunal luminal bacteria. Translocation of aerobic and anaerobic bacteria into the intestinal wall, mesenteric lymph nodes, liver and spleen was determined by counting bacterial colonies on agar plates 48h after plating of tissue homogenates. Antimicrobial activity against E. coli and B. vulgatus was analyzed in total and cationic fractions of small bowel mucosal tissue homogenates by a flow cytometry-based bacterial depolarization assay. RESULTS: Jejunal bacterial overgrowth was detected 24h after surgery. At the same time point, but not in the early phase 3h after surgery, bacterial translocation into the liver and mesenteric lymph nodes was observed. Increased antimicrobial activity against E. coli was induced within early phase of POI. Basal antimicrobial peptide and enzyme gene expression was higher in the ileal compared to the jejunal mucosa. The expression of lysozyme 1, cryptdin 1, cryptdin 4 and mucin 2 were reduced 24h after surgery in the ileal mucosa and mucin 2 was also reduced in the jejunum. Postoperative IL-1α and IL-1ß were increased in the postoperative mucosa. Deficiency of IL-1R1 affected the expression of antimicrobial peptides during homeostasis and POI. CONCLUSION: Small bowel antimicrobial capacity is disturbed during POI which is accompanied by bacterial overgrowth and translocation. IL-1R1 is partially involved in the gene expression of mucosal antimicrobial peptides. Altered small bowel antimicrobial activity may contribute also to POI development and manifestation in patients undergoing abdominal surgery.

Ileus in Adults.

BACKGROUND: Ileus is one of the more common suspected diagnoses in everyday clinical practice. The term can refer either to mechanical or to functional ileus. Any physician who takes care of patients can be confronted with these entities; thus, all should be familiar with them and competent in their management. METHODS: Recommendations are summarized for the diagnostic evaluation and treatment of ileus of various causes on the basis of a selective literature review. RESULTS: The manifestations of ileus and its degree of severity generally depend on the site of blockage. The rule until recently was that a patient with suspected mechanical ileus should be taken to surgery within 12 hours; today, however, ileus-particularly of the small bowel-can often be successfully treated conservatively. Likewise, functional ileus only rarely requires surgery: supportive measures, depending on the etiology, usually suffice. CONCLUSION: Proper treatment depends on the timely determination of the pathogenesis (mechanical versus functional) and on close interdisciplinary collaboration. A special challenge is posed by patients with peritoneal involvement with cancer who present with symptoms of ileus, in whom a clear distinction between mechanical and functional causation cannot always be drawn.

Incidentally Detected Focal Liver Lesions - A Common Clinical Management Dilemma Revisited.

BACKGROUND: Detection of asymptomatic focal liver lesions (FLL) is increasing because of a widespread use of modern radiologic imaging. Most of these lesions are benign, though malignancy often has to be ruled out, which is posing a diagnostic challenge. AIM: To critically evaluate our treatment strategy in the context of recently published American College of Gastroenterology (ACG) guidelines. PATIENTS AND METHODS: The medical records of patients who underwent surgery for asymptomatic, incidentally detected FLL from 2005-2012 were reviewed. Primary end-points were the congruence of suspected diagnosis and final pathology, as well as the identification of predictors of malignancy. A systematic review was undertaken to help define a standardized management. RESULTS: Eighty patients, 37 male and 43 female with a mean age of 57 years (range=16-83) were included, harboring 39 (49%) malignant and 41 (51%) benign, asymptomatic hepatic lesions. Hepatocellular carcinoma (HCC) (n=24) represented most of malignant FLL, followed by cholangiocellular carcinoma (CCC) (n=10), whereas focal nodular hyperplasia (FNH) (n=19) and liver hemangioma (n=7) were the predominant benign entities. Fifty-one patients (64%) had a correct preoperative diagnosis, while patients with FNH were most commonly misdiagnosed (53%). We identified age (p<0.001) and male sex (p=0.013) as risk factors for malignancy in an asymptomatic FLL. CONCLUSION: Despite recent technical advances of the modern radiology setting a correct preoperative diagnosis in an asymptomatic FLL remains challenging. Male gender and old age seem to correlate with malignancy. In the absence of biomarkers and evidence-based guidelines, a multidisciplinary approach in an experienced tertiary referral center is recommended for an optimized individual management.

An Improved Suture Technique for Perform Biliary Reconstruction in Orthotopic Liver Transplantation.

BACKGROUND: The biliary anastomosis remains to be the Achilles' heel of liver transplantation. The incidence of biliary complications (e.g., stenosis and leakage) is immanent and the optimal type of reconstruction is unclear. The aim of this study was to compare 2 different bile duct suture techniques regarding their benefits in the prevention of biliary complications. MATERIAL AND METHODS: From 1992 to 2012, the transplanted patients (n=394) of our center were analyzed retrospectively in terms of suture techniques and consecutive biliary complications. Secondary, possible risk factors (cold ischemic time, donor age, and preoperative liver function) were examined. An end-to-end choledocho-choledochostomy without T-tube was performed during orthotopic liver transplantation whenever possible. In group 1 (n=123) the biliary reconstruction was performed completely by continuous-suture technique. In group 2 (n=164) continuous-suture technique was also performed in posterior wall of the bile duct, but the anterior wall was closed by interrupted-suture technique. RESULTS: The overall biliary complication rate was 19.6%. There were no significant differences in biliary complications between the groups. Analysis of risk factors showed no influence on the complication rate. CONCLUSIONS: The argument for the interrupted-suture technique is a better overview and a lower risk to grab the posterior wall during the anastomotic realization. The threads of the anterior wall can be presented individually and then be knotted.

Biliary intraepithelial neoplasia (BilIN) is frequently found in surgical margins of biliary tract cancer resection specimens but has no clinical implications.

Biliary tract cancers are aggressive tumors of which the incidence seems to increase. Resection with cancer-free margins is crucial for curative therapy. However, how often biliary intraepithelial neoplasia (BilIN) occurs in resection margins and what its clinical and therapeutic implications might be is largely unknown. We reexamined margins of resection specimens of adenocarcinoma of the biliary tree including the gallbladder for the presence of BilIN. When present, it was graded. The findings were correlated with clinicopathological parameters and overall survival. Complete examination of the resection margin could be performed on 55 of 78 specimens (71%). BilIN was detected in the margin in 29 specimens (53%) and was mainly low-grade (BilIN-1; N = 14 of 29; 48%). In resection specimens of extrahepatic cholangiocarcinoma, BilIN was most frequent (N = 6 of 8; 75%). BilIN was found in the resection margin more frequently in extrahepatic cholangiocarcinomas (P = 0.007) and in large primary tumors (P = 0.001) with lymphovascular (P = 0.006) and perineural invasion (P = 0.049). Patients with cancer in the resection margin (R1) had a significantly shorter overall survival than those with resection margins free of tumor (R0) irrespective of the presence of BilIN (R0 vs R1; P < 0.001) or BilIN grade (BilIN-positive vs BilIN-negative, P = 0.6, and BilIN-1 + 2 vs BilIN-3, P = 0.58). BilIN is frequently found in the surgical margin of resection specimens of adenocarcinoma of the biliary tract. Hepatopancreatobiliary surgeons will be confronted with this recently defined entity when an intraoperative frozen section of a resection margin is requested. However, this diagnosis does not require additional resection and in the intraoperative evaluation of resection, the emphasis should remain on the detection of residual invasive tumor.

Postoperative ileus involves interleukin-1 receptor signaling in enteric glia.

BACKGROUND & AIMS: Postoperative ileus (POI) is a common consequence of abdominal surgery that increases the risk of postoperative complications and morbidity. We investigated the cellular mechanisms and immune responses involved in the pathogenesis of POI. METHODS: We studied a mouse model of POI in which intestinal manipulation leads to inflammation of the muscularis externa and disrupts motility. We used C57BL/6 (control) mice as well as mice deficient in Toll-like receptors (TLRs) and cytokine signaling components (TLR-2(-/-), TLR-4(-/-), TLR-2/4(-/-), MyD88(-/-), MyD88/TLR adaptor molecule 1(-/-), interleukin-1 receptor [IL-1R1](-/-), and interleukin (IL)-18(-/-) mice). Bone marrow transplantation experiments were performed to determine which cytokine receptors and cell types are involved in the pathogenesis of POI. RESULTS: Development of POI did not require TLRs 2, 4, or 9 or MyD88/TLR adaptor molecule 2 but did require MyD88, indicating a role for IL-1R1. IL-1R1(-/-) mice did not develop POI; however, mice deficient in IL-18, which also signals via MyD88, developed POI. Mice given injections of an IL-1 receptor antagonist (anakinra) or antibodies to deplete IL-1α and IL-1ß before intestinal manipulation were protected from POI. Induction of POI activated the inflammasome in muscularis externa tissues of C57BL6 mice, and IL-1α and IL-1ß were released in ex vivo organ bath cultures. In bone marrow transplantation experiments, the development of POI required activation of IL-1 receptor in nonhematopoietic cells. IL-1R1 was expressed by enteric glial cells in the myenteric plexus layer, and cultured primary enteric glia cells expressed IL-6 and the chemokine monocyte chemotactic protein 1 in response to IL-1ß stimulation. Immunohistochemical analysis of human small bowel tissue samples confirmed expression of IL-1R1 in the ganglia of the myenteric plexus. CONCLUSIONS: IL-1 signaling, via IL-1R1 and MyD88, is required for development of POI after intestinal manipulation in mice. Agents that interfere with the IL-1 signaling pathway are likely to be effective in the treatment of POI.

Functional assessment of intestinal motility and gut wall inflammation in rodents: analyses in a standardized model of intestinal manipulation.

Inflammation of the gastrointestinal tract is a common reason for a variety of human diseases. Animal research models are critical in investigating the complex cellular and molecular of intestinal pathology. Although the tunica mucosa is often the organ of interest in many inflammatory diseases, recent works demonstrated that the muscularis externa (ME) is also a highly immunocompetent organ that harbours a dense network of resident immunocytes.(1,2) These works were performed within the standardized model of intestinal manipulation (IM) that leads to inflammation of the bowel wall, mainly limited to the ME. Clinically this inflammation leads to prolonged intestinal dysmotility, known as postoperative ileus (POI) which is a frequent and unavoidable complication after abdominal surgery.(3) The inflammation is characterized by liberation of proinflammatory mediators such as IL-6(4) or IL-1ß or inhibitory neurotransmitters like nitric oxide (NO).(5) Subsequently, tremendous numbers of immunocytes extravasate into the ME, dominated by polymorphonuclear neutrophils (PMN) and monocytes and finally maintain POI.(2) Lasting for days, this intestinal paralysis leads to an increased risk of aspiration, bacterial translocation and infectious complications up to sepsis and multi organ failure and causes a high economic burden.(6) In this manuscript we demonstrate the standardized model of IM and in vivo assessment of gastrointestinal transit (GIT) and colonic transit. Furthermore we demonstrate a method for separation of the ME from the tunica mucosa followed by immunological analysis, which is crucial to distinguish between the inflammatory responses in these both highly immunoactive bowel wall compartments. All analyses are easily transferable to any other research models, affecting gastrointestinal function.

Differential molecular and cellular immune mechanisms of postoperative and LPS-induced ileus in mice and rats.

Ileus is caused by the initiation of a complex cascade of molecular and cellular inflammatory responses within the intestinal muscularis, which might be species specific. Our objective was to investigate a possible immunological divergence in the mechanisms of postoperative- and endotoxin-induced ileus in C57BL/6 mice and Sprague-Dawley rats. Gastrointestinal transit (GIT) was measured at 24 h after the injurious stimulus. MPO-staining and F4/80 immunohistochemistry were used to quantify polymorphonuclear and monocyte infiltration of jejunal muscularis whole-mounts, and intestinal muscularis MCP-1, ICAM-1 and iNOS gene expression was assessed by RT-PCR. Intestinal muscularis subjected to in vivo surgical manipulation (SM) or LPS treatment was cultured for 24 h, and the liberation of nitric oxide and chemokines/cytokines into the culture medium was analyzed by Griess reaction and Luminex multiplex assay. Intestinal SM and lipopolysaccharide (LPS) (15 mg/kg) caused a significant delay in gastrointestinal transit, which was more severe in mice compared to rats in both injury models. Both SM- and LPS-triggered neutrophil and monocytic extravasation into the rat jejunal muscularis exceeded the cellular infiltration seen in mice. These results correlated with significantly greater increases in rat muscularis MCP-1 (syn. CCL2), ICAM-1 and iNOS message with more subsequent NO production after SM or LPS compared to mouse. The cultured muscularis obtained from SM mice released significantly more inflammatory proteins such as TNF-α, IL-1-α, IL-4 and GM-CSF compared to the manipulated rat muscularis. In contrast, LPS initiated the secretion of significantly more IL-1ß by the inflamed rat muscularis compared to the mouse, but GM-CSF (syn. CSF2) liberation from mouse muscularis was markedly higher compared to LPS-treated rat muscularis. The data indicate that mechanistically the development of ileus in rat is mediated predominately through a leukocytic pathway consisting of chemotaxis, cellular extravasation and NO liberation. Whereas, the more intense mouse ileus evolves via a potent but injury-specific local cytokine response.

Immune mediators of postoperative ileus.

UNLABELLED: CLINICAL BACKGROUND: In all patients undergoing abdominal surgery, a transient phase of interruption of bowel motility, named postoperative ileus (POI) occurs. POI is often accepted as an unavoidable "physiological" response and a self-limiting complication after surgery although it has a significant impact on patient morbidity with prolonged hospitalization and increased costs. Annual economic burden has been estimated as much as US $1.47 billion in the USA (Iyer et al. in J Manag Care Pharm 15(6):485-494, 2009). PATHOPHYSIOLOGY: The pathophysiology has been elucidated within the last decades, demonstrating that both, neurogenic and inflammatory mechanisms are involved in response to the surgical trauma. It is now generally accepted that POI pathogenesis processes in two phases: a first neurogenic phase is accountable for the immediate postoperative impairment of bowel motility. This is followed by a second immunological phase that can last for days and mainly affects strength and length of POI. More recent findings demonstrate a bidirectional interaction between the nervous and the immune system, and this interaction significantly contributed to our present understanding of POI pathophysiology. Although nerval mechanisms have a significant impact in the early phase of POI, the contribution of the immune system and subsequently its manipulation has risen as the most promising strategy in prevention or treatment of the clinically relevant prolonged form of POI. AIMS: The present manuscript will give an update on the inflammatory responses, the involved cell types, and participating immune mediators in POI.

Effects of immunosuppressive therapy after experimental small bowel transplantation in rats.

Significant improvements of graft and patient survival have been achieved over the past 20 years in the field of intestinal transplantation. Tacrolimus monotherapy with corticosteroids, or in combination with sirolimus is the most commonly used immunosuppressive regimen. Early (24h) after experimental allogenic small bowel transplantation in rats, sirolimus reduces the cellular and molecular inflammatory response with subsequent graft dysmotility more efficiently than tacrolimus, with contrary effects at 7 days after transplantation. This study evaluates three immunosuppressive strategies in the post-acute phase after intestinal transplantation - tacrolimus or sirolimus monotherapy and the combination therapy of tacrolimus with infliximab. After orthotopic intestinal transplantation between Brown Norway and Lewis rats, animals received 14 days of immunosuppressive treatment. Histology, infiltration of neutrophils, monocytes and macrophages, cytokine and mediator mRNA expression (real time RT-PCR) and smooth muscle function in a standard organ bath were assessed at 14 days after transplantation in all treatment groups and isogenic controls. Allogenic transplanted rats without immunosuppressive therapy and non-transplanted animals served as further control. Tacrolimus prevented acute rejection and graft dysmotility more effectively (p ≥ 0.05) than sirolimus. Reduced mRNA expression levels of CD4, IFN-γ, IL-6, IL-10, iNOS, NFκB, TNF-α and MCP-1 (p ≤ 0.05) were observed in tacrolimus treated animals compared to sirolimus. Additional infliximab application did not influence the cellular and molecular inflammatory response in the post-acute phase after transplantation. In conclusion, the severe cellular and molecular inflammatory response in allogenic transplanted grafts without immunosuppressive therapy is ameliorated by all three immunosuppressive regimens, but tacrolimus was found to be more efficient than sirolimus at 14 days after transplantation. Our findings do not rule out the usage of sirolimus as single immunosuppressive therapy, but indicate and confirm the potency and effectivity of tacrolimus as basis immunosuppressant in the field of intestinal transplantation.

Colonic anastomotic healing in the context of altered macrophage function and endotoxemia.

PURPOSE: Prevention of perioperative activation of intestinal muscularis macrophages is a promising intervention to avoid post-traumatic gastrointestinal tract dysfunction. However, impaired macrophage function could have deleterious consequences on anastomotic healing, especially in complications aggravating the healing process itself, such as infectious problems either as preexisting local inflammation or infection (e.g., complicated diverticulitis) or endotoxemia due to early postoperative infections (e.g., pneumonia). Aim of this study was to investigate colonic anastomotic healing in macrophage-depleted mice in the presence of endotoxemia. METHODS: Colonic anastomoses were performed, and mice were randomized into six groups (wild type; wild type with endotoxemia; pharmacological depletion of macrophages; pharmacological depletion with endotoxemia; genetically conditioned within the gut muscularis macrophage-deficient osteopetrotic mice; osteopetrotic mice with endotoxemia). Anastomotic tissues were removed 2, 5, and 10 days after surgery and used for functional, histological, biochemical, and molecular investigations. RESULTS: After pharmacological pretreatment, an almost complete depletion of macrophages was found in the muscularis up to 24 h postoperatively. Bursting pressure was significantly lower than 10 days after anastomotic procedure in osteopetrotic mice during endotoxemia, in marked contrast to transient pharmacologically macrophage-depleted mice. Pharmacological depletion during endotoxemia did not affect hydroxyproline concentration. Finally, in osteopetrotic mice during endotoxemia, collagen-3 expression was significantly lower compared to controls. CONCLUSIONS: In our current model, we demonstrate that perioperative pharmacological macrophage depletion and inactivation transiently diminishes muscularis macrophages and does not affect intestinal anastomotic healing in the presence of endotoxemia. However, a long-lasting macrophage absence or dysfunction impairs anastomotic healing and could be a risk factor for postoperative anastomotic leakage.

IL-10 deficiency augments acute lung but not liver injury in hemorrhagic shock.

In hemorrhagic shock and trauma, patients are prone to develop systemic inflammation with remote organ dysfunction, which is thought to be caused by pro-inflammatory mediators. This study investigates the role of the immuno-modulatory cytokine IL-10 in the development of organ dysfunction following hemorrhagic shock. Male C57/BL6 and IL-10 KO mice were subjected to volume controlled hemorrhagic shock for 3h followed by resuscitation. Animals were either sacrificed 3 or 24h after resuscitation. To assess systemic inflammation, serum IL-6, IL-10, KC, and MCP-1 concentrations were measured with the Luminex multiplexing platform; acute lung injury (ALI) was assessed by pulmonary myeloperoxidase (MPO) activity and lung histology and acute liver injury was assessed by hepatic MPO activity, hepatic IL-6 levels, and serum ALT levels. There was a trend towards increased IL-6 and KC serum levels 3h after resuscitation in IL-10 KO as compared to C57/BL6 mice; however this did not reach statistical significance. Serum MCP-1 levels were significantly increased in IL-10 KO mice 3 and 24 h following resuscitation as compared to C57/BL6 mice. In IL-10 KO mice, pulmonary MPO activity was significantly increased 3 h following resuscitation and after 24 h histological signs of acute lung injury were more apparent than in C57/BL6 mice. In contrast, no significant differences in any liver parameters were detected between IL-10 KO and C57/BL6 mice. Our data indicate that an endogenous IL-10 deficiency augments acute lung but not liver injury following hemorrhagic shock.

Proinflammatory role of leukocyte-derived Egr-1 in the development of murine postoperative ileus.

BACKGROUND & AIMS: Early growth response gene-1 (Egr-1) is an important inflammatory transcription factor. We hypothesize that leukocyte-derived Egr-1 plays a key inflammatory role in causing postoperative ileus. METHODS: Wild-type, Egr-1 knockout, and chimera mice (constructed by irradiation followed by injection with Egr-1(+/+) or Egr-1(-/-) bone marrow) were subjected to surgical manipulation of the gastrointestinal tract to induce ileus. Reverse-transcription polymerase chain reaction, Western blot, and immunohistochemistry quantified and localized Egr-1. Lumenal transit of nonabsorbable fluorescein isothiocyanate-labeled dextran and in vitro organ bath techniques measured functional gastrointestinal motility. Inflammatory mediator expressions were measured by Griess reaction, enzyme-linked immunosorbent assay, and multiplex Luminex assay. RESULTS: Intestinal manipulation rapidly and significantly induced Egr-1 messenger RNA and protein within the inflamed muscularis externa. Egr-1 was colocalized early to smooth muscle and enteric neurons and later in extravasated monocytes after surgery when postoperative ileus was functionally prominent. The functional severity of postoperative ileus was significantly ameliorated in mice deficient in Egr-1(-/-) and chimera wild-type mice transplanted with Egr-1(-/-) bone marrow, whereas knockout mice with Egr-1(+/+) bone marrow again displayed significant ileus. Motility was mechanistically associated in Egr-1(-/-) gene deficiency with a down-regulation in the release of nitric oxide, prostanoids, monocyte chemoattractant protein-1, macrophage inflammatory protein-1alpha, interleukin-6, interleukin-1, and granulocyte colony-stimulating factor, as well as a decrease in the recruitment of leukocytes into the manipulated muscle wall of the intestine compared with wild-type mice. CONCLUSIONS: Leukocyte-derived Egr-1 plays an early critical inflammatory role in the initiation of the postoperative inflammatory response, which leads to a prolonged decreased in gastrointestinal motility after intestinal surgery.

A single intraperitoneal dose of carbon monoxide-saturated ringer's lactate solution ameliorates postoperative ileus in mice.

Treatment with inhaled carbon monoxide (CO) has been shown to ameliorate bowel dysmotility caused by surgical manipulation of the gut in experimental animals. We hypothesized that administration of CO dissolved in lactated Ringer's solution (CO-LR) might provide similar protection to that observed with the inhaled gas while obviating some of its inherent problems. Postoperative gut dysmotility (ileus) was induced in mice by surgical manipulation of the small intestine. Some mice were treated with a single intraperitoneal dose of CO-LR immediately after the surgical procedure, whereas other mice received only the LR vehicle. Twenty-four hours later, intestinal transit of a nonabsorbable marker (70-kDa fluorescein isothiocyanate-labeled dextran) was delayed in mice subjected to intestinal manipulation but not the sham procedure. Gut manipulation also was associated with increased expression within the muscularis propria of transcripts for interleukin-1beta, cyclooxygenase-2, inducible nitric-oxide synthase, intracellular adhesion molecule-1, and Toll-like receptor-4, as well as infiltration of the muscularis propria with polymorphonuclear leukocytes and activation of mitogen-activated protein kinases and nuclear factor-kappaB. All of these effects were attenuated by treatment with CO-LR. The salutary effect of CO-LR on gut motility, as well as many of the anti-inflammatory effects of CO-LR, was diminished by treatment with a soluble guanylyl cyclase (sGC) inhibitor, suggesting that the effects of CO are mediated via activation of sGC. These data support the view that a single intraperitoneal dose of CO-LR ameliorates postoperative ileus in mice by inhibiting the inflammatory response in the gut wall induced by surgical manipulation, possibly in a sGC-dependent fashion.