Adrenal insufficiency is a contraindication for omalizumab therapy in mast cell activation disease: risk for serum sickness

Omalizumab is an effective therapeutic humanized murine IgE antibody in many cases of primary systemic mast cell activation disease (MCAD). The present study should enable the clinician to recognize when treatment of MCAD with omalizumab is contraindicated because of the potential risk of severe serum sickness and to report our successful therapeutic strategy for such adverse event (AE). Our clinical observations, a review of the literature including the event reports in the FDA AE Reporting System, the European Medicines Agency Eudra-Vigilance databases (preferred search terms: omalizumab, Xolair®, and serum sickness) and information from the manufacturer’s Novartis database were used. Omalizumab therapy may be more likely to cause serum sickness than previously thought. In patients with regular adrenal function, serum sickness can occur after 3 to 10 days which resolves after the antigen and circulating immune complexes are cleared. If the symptoms do not resolve within a week, injection of 20 to 40 mg of prednisolone on two consecutive days could be given. However, in MCAD patients whose adrenal cortical function is completely suppressed by exogenous glucocorticoid therapy, there is a high risk that serum sickness will be masked by the MCAD and evolve in a severe form with pronounced damage of organs and tissues, potentially leading to death. Therefore, before the application of the first omalizumab dose, it is important to ensure that the function of the adrenal cortex is not significantly limited so that any occurring type III allergy can be self-limiting.

Endoscopic full-thickness resection using an over-the-scope device for treatment of recurrent / residual colorectal neoplasia: a single-center case series

Background

Endoscopic mucosal resection (EMR) in piecemeal technique is the treatment standard for larger flat or sessile colorectal lesions. The method is burdened by a high recurrence rate mostly presenting as difficult to resect lesions. In these situations, endoscopic full thickness resection (EFTR) with an over-the-scope device offers the option of complete resection despite scar formation.

Methods

We conducted a retrospective case review of 30 consecutive EFTR interventions on small (< 20 mm), difficult to resect recurrent / residual colorectal neoplastic lesions treated by EFTR.

Results

EFTR was technically feasible in 28/30 (93,3%) of the cases with an R0 resection in 24/30 (80%) and a median procedure time (marking to full thickness resection) of 34,5 min (11–120). After the first 15 procedures, the per-protocol rate increased from 13/15 to 15/15 and the R0 resection rate increased from 9/15 (69,2%) to 15/15 (100,0%; p < 0.01). One patient suffered from a delayed perforation the day after the procedure and needed emergency surgery (3,6%). Minor bleeding occurred in 3/28 patients (10,7%) and post-interventional fever in one patient (3,6%). The 30-day mortality rate was 0%.

Conclusions

EFTR with an over-the-scope device is a useful method for endoscopic resection of difficult to treat recurrent or residual colorectal neoplasia after previous endoscopic therapy. High R0 resection rates were observed after a relatively short learning curve. The complication rate in this series seems acceptable given the complexity of the resected lesions.

Implementation of endoscopic submucosal dissection for early upper gastrointestinal tract cancer after primary experience in colorectal endoscopic submucosal dissection

Background  Current guidelines recommend endoscopic submucosal dissection (ESD) as a treatment option for early cancers of the upper gastrointestinal tract with absent or minimal risk of lymph node metastasis. However, due to the low prevalence of these entities, it is difficult to achieve a competence level for ESD of upper gastrointestinal tract cancers in the Western World. Here, we present single-center data on the implementation of upper gastrointestinal ESD after previous experience with 89 colorectal ESD cases. Methods  Retrospective case series of 39 consecutive patients with early cancers of the esophagus (n = 13) or cardia and stomach (n = 26) treated with ESD over a 4-year period. Results  ESD was technically feasible in all cases with en bloc, R0, and curative resection rates of 100 %, 76.9 %, and 71.8 %, respectively, and a mean procedure time of 100 minutes (30 - 360 minutes). After an initial 20 procedures, the R0 and curative resection rates increased from 65.0 % to 89.5 %, and from 60.0 % to 84.2 %, respectively. Complications were observed in four patients (10.3 %): three perforations, one case of delayed bleeding, and one esophageal stricture. No case required emergency surgery; the 30-day mortality rate was 0 %. Conclusion  In this modest case series from Europe, we observed an effectiveness and complication rate for ESD for early esophageal and gastric cancer that are comparable to other series from Europe but also to more abundant data from Asia. The results indicate that even small numbers of upper gastrointestinal cancers can be managed adequately in centers with expertise in colorectal ESD.

[Surgical interventions in patients with systemic mast cell activation disease : Recommendations for perioperative management]

BACKGROUND

Systemic mast cell activation disease (MCAD, prevalence 5-10%) is a multifactorial, polygenic disease with multisystemic symptoms that is characterized by an unregulated increased release of mast cell mediators and an accumulation of activated mast cells potentially in all organs and tissues. Due to the high prevalence of the disease, physicians involved in surgical, anesthesiological and interventional procedures are often unknowingly faced with MCAD patients experiencing unexpected preoperative, intraoperative and postoperative complications, if no mast cell-specific treatment regimens have been applied.

OBJECTIVE

The findings from a literature search, consensus recommendations of the various international expert groups and extensive own experience in the treatment of MCAD patients enable an empirical and evidence-based care of MCAD patients in association with invasive procedures.

RESULTS AND CONCLUSION

Due to the high prevalence of MCAD in the population, it can be assumed that patients with MCAD are correspondingly frequently represented in the surgical patient collective. When MCAD-specific peculiarities are preventively considered in the anesthesiological and surgical procedures in patients with proven or suspected mast cell disease, MCAD patients should not be classified as being at risk.

Full-thickness resection with an over-the-scope device: possible translocation of adenoma tissue in a case of an incomplete resection at the appendix

Background and study aims  Clip-assisted endoscopic full-thickness resection has great potential for treatment of difficult-to-resect colorectal neoplasia. Here, we report on endoscopic full-thickness resection at the appendiceal orifice with the appendix in situ requiring emergency surgery due to acute appendicitis. Final histopathology showed appendicitis and residual serrated adenoma within the appendiceal stump, but unexpectedly, also a displaced adenoma fragment at the serosal surface of the cecum. Given the transmural placement of the clip prior to snare resection, translocation of neoplastic tissue to the extra luminal site in cases of incomplete adenoma/carcinoma resection could be a concern.

Endoscopic submucosal dissection for flat or sessile colorectal neoplasia > 20 mm: A European single-center series of 182 cases

BACKGROUND AND STUDY AIMS

Colorectal endoscopic submucosal dissection (ESD) is an attractive method for en bloc resection of larger flat neoplastic lesions. Experience with this method is limited in the Western World.

PATIENTS AND METHODS

A total of 182 consecutive flat or sessile colorectal lesions (cecum n = 43; right-sided colon n = 65; left-sided colon n = 11, rectum: n = 63) with a size > 20 mm (mean 41.0 ± 17.4 mm) were resected in 178 patients. The data were recorded prospectively.

RESULTS

ESD was technically feasible in 85.2 % of patients with a mean procedure time of 127.5 min (± 99.8) min and a complication rate of 11.5 % (microperforation 9.3 %, delayed bleeding 2.7 %, no case of emergency surgery, 30-day mortality rate 0 %). For 155 successfully completed procedures the en bloc and R0 resection rates were 88.4 and 62.6 %. Efficacy was better for smaller lesions (20 mm to 49 mm; n = 131) than for larger lesions (50 mm to 140 mm; n = 51) with R0 rates of 70.8 vs. 40.5 % (P < 0.001) and procedure times of 92.7 ± 62.4 minutes vs. 217.0 ± 120.9 minutes (P < 0,001).

CONCLUSIONS

This series confirms the efficacy of ESD for en bloc resection of colorectal lesions > 20 mm. RESULTS are satisfactory for lesions up to 50 mm. ESD for larger lesions was associated with low R0 resection rates and very long procedure times. The clinical consequences of microperforations were minor and do not argue against the spread of ESD in the West. Meeting presentations: The data were presented in part at DDW 2014, Chicago IL, USA (Gastrointest Endosc 2014; 79: AB536).

Endoscopic mucosal resection of colorectal adenomas > 20 mm: Risk factors for recurrence

AIM: To evaluate risk factors for local recurrence after endoscopic mucosal resection of colorectal adenomas > 20 mm.

METHODS: Retrospective data analysis of 216 endoscopic mucosal resections for colorectal adenomas > 20 mm in 179 patients (40.3% female; median age 68 years; range 35-91 years). All patients had at least 1 follow-up endoscopy with a minimum control interval of 2 mo (mean follow-up 6 mo/2.0-43.4 mo). Possible factors associated with local recurrence were analyzed by univariate and multivariate analysis.

RESULTS: Median size of the lesions was 30 mm (20-70 mm), 69.0% were localized in the right-sided (cecum, ascending and transverse) colon. Most of the lesions (85.6%) showed a non-pedunculated morphology and the majority of resections was in piecemeal technique (78.7%). Histology showed carcinoma or high-grade intraepithelial neoplasia in 51/216 (23.6%) lesions including 4 low risk carcinomas (pT1a, L0, V0, R0 - G1/G2). Histologically proven recurrence was observed in 33/216 patients (15.3%). Patient age > 65 years, polyp size > 30 mm, non-pedunculated morphology, localization in the right-sided colon, piecemeal resection and tubular-villous histology were found as associated factors in univariate analysis. On multivariate analysis, only localization in the right-sided colon (HR = 6.842/95%CI: 1.540-30.394; P = 0.011), tubular-villous histology (HR = 3.713/95%CI: 1.617-8.528; P = 0.002) and polyp size > 30 mm (HR = 2.563/95%CI: 1.179-5.570; P = 0.017) were significantly associated risk factors for adenoma recurrence.

CONCLUSION: Meticulous endoscopic follow-up is warranted after endoscopic mucosal resection of adenomas localized in the right-sided colon larger than > 30 mm, with tubular-villous histology.

[Surgical interventions in patients with mast cell activation disease. Aspects relevant for surgery using the example of a cholecystectomy]

BACKGROUND

Systemic mast cell activation disease (MCAD) is characterized by an increased and unregulated release of mast cell mediators which can evoke a multifaceted clinical picture often resembling irritable bowel syndrome or fibromyalgia. Because of the considerable prevalence (~ 17 %) of MCAD surgeons are frequently unwittingly confronted with MCAD patients in whom unexpected intraoperative and postoperative complications may occur. Therefore, knowledge of the particular requirements is of relevance for surgical treatment of MCAD patients.

OBJECTIVE

The present paper outlines a concept of surgical treatment of MCAD patients based on the literature which is illustrated by a case report on emergency laparoscopic cholecystectomy.

CONCLUSIONS

Due to the high prevalence of MCAD in the general population it can be assumed that the frequency in the surgical patient population is similar. If a patient has MCAD, specific characteristics should be taken into account in the surgical procedure to avoid increased operative and complication risks resulting from MCAD.

Endoscopic Submucosal Dissection (ESD) in Colorectal Tumors

Background

Endoscopic submucosal dissection (ESD) – initially developed for the treatment of early gastric cancer in Japan – is an attractive option for en bloc resection of larger sessile or flat colorectal neoplasia.

Methods

A review of the current literature on colorectal ESD was carried out.

Results

In contrast to conventional endoscopic mucosal resection (EMR), ESD for larger colorectal neoplasia yields high en bloc resection rates and very low recurrence rates. The frequency of delayed bleeding is similar for EMR and ESD. Higher perforation rates during ESD are mostly due to microperforations identified and treated during the intervention, and are therefore of minor clinical relevance. A major disadvantage of ESD is the necessity for high-level endoscopic skills and long procedure times. ESD also has the potential to replace laparoscopic surgery or transanal endoscopic microsurgery mainly due to its lower complication rates.

Conclusion

ESD for the resection of larger flat or sessile colorectal lesions has potential advantages over conventional EMR or minimally invasive surgery. Due to the low incidence of early gastric cancer, experience with ESD will remain limited in Western countries. The spread of colorectal ESD will depend on adequate training opportunities and also on modifications yielding a reduction in procedure time.

Selective downregulation of retinoic acid-inducible gene I within the intestinal epithelial compartment in Crohn's disease

BACKGROUND

A defective innate immune response may contribute to the pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC). Employing a global gene expression analysis, this study was aimed at identifying specifically regulated genes within the epithelial compartment in inflammatory bowel disease (IBD).

METHODS

The epithelial fraction of human ileal mucosa samples from surgical specimens was obtained by laser microdissection. Gene expression was examined by global expression profiling (n = 18, Affymetrix), quantitative reverse-transcription polymerase chain reaction (RT-PCR) (n = 35), immunoblot analysis (n = 9), and immunohistochemistry (n = 25).

RESULTS

Global expression profiling revealed a pronounced downregulation of the retinoic acid-inducible gene I (RIG-I) within the epithelial layer of the ileum in patients with CD but not with UC. The downregulation of RIG-I was confirmed by quantitative RT-PCR, immunoblot analysis, and immunohistochemistry.

CONCLUSIONS

Epithelial downregulation of RIG-I, a known pattern recognition receptor for viral components, might contribute to alterations of the innate mucosal immune response, particularly in CD.

Functional characterisation of decoy receptor 3 in Crohn's disease

AIMS

Both epithelial barrier dysfunction and apoptosis resistance of immune cells contribute to the pathogenesis of Crohn's disease. The soluble decoy receptor 3 (DcR3) acts in an anti-apoptotic manner by neutralising the death ligand CD95L. Here, we investigated the possible involvement of DcR3 in Crohn's disease.

METHODS

The epithelial fraction of human small intestinal mucosa samples was obtained by laser microdissection. Expression of DcR3 was examined by global gene expression profiling, quantitative reverse transcription polymerase chain reaction, immunoblot analysis, and immunohistochemistry. DcR3 concentrations in the serum of patients with Crohn's disease were measured by enzyme-linked immunosorbent assay. Apoptosis assays were performed to study the effects of DcR3 in intestinal epithelial cells and lamina propria T cells.

RESULTS

DcR3 is over-expressed in the epithelial layer of ileum specimens in patients with Crohn's disease, both at actively inflamed and non-active sites. DcR3 serum levels are significantly elevated in patients with active and non-active Crohn's disease as compared to healthy controls. The expression of DcR3 in intestinal epithelial cells is induced by tumour necrosis factor alpha. Increased DcR3 expression is associated with activation of nuclear factor kappa B (NF-kappaB) and results in protection of intestinal epithelial cells and lamina propria T cells from CD95L-induced apoptosis.

CONCLUSIONS

DcR3 may promote inflammation in Crohn's disease by inhibiting CD95L-induced apoptosis of epithelial and immune cells as well as by inducing NF-kappaB activation.

Up-regulation of the phosphoinositide 3-kinase pathway in human lamina propria T lymphocytes

Human intestinal lamina propria T lymphocytes (LPT), when investigated ex vivo, exhibit functional properties profoundly different from those of peripheral blood T lymphocytes (PBT). One prominent feature represents their enhanced sensitivity to CD2 stimulation when compared to PBT. Given that LPT are hyporesponsive to T cell receptor (TCR)/CD3 stimulation, an alternative activation mode, as mimicked by CD2 triggering in vitro, may be functional in mucosal inflammation in vivo. This study provides insight into signalling events associated with the high CD2 responsiveness of LPT. When compared to PBT, LPT show an increased activation of the phosphoinositide 3/protein kinase B/glycogen synthase kinase 3beta (PI3-kinase/AKT/GSK-3beta) pathway in response to CD2 stimulation. Evidence is provided that up-regulation of this pathway contributes to the enhanced CD2-induced cytokine production in LPT. Given the importance of TCR-independent stimulation for the initiation of intestinal immune responses analysis of signalling pathways induced by 'co-stimulatory' receptors may provide valuable information for therapeutic drug design.

A prominent role for mucosal cystine/cysteine metabolism in intestinal immunoregulation

BACKGROUND & AIMS

T-cell receptor reactivity of intestinal lamina propria T cells (LP-T) critically depends on the capacity of local accessory cells to secrete cysteine. For T cells, cysteine is the limiting precursor for glutathione synthesis, a prerequisite for antigen-dependent proliferation. We aimed to determine the role of the redoxactive microenvironment for hyporeactivity of LP-T in normal human gut vs hyperreactivity of LP-T in inflammatory bowel disease.

METHODS

Parameters relevant to cysteine production, determined as acid-soluble thiol, by intestinal lamina propria macrophages (LP-MO) vs peripheral blood monocytes were investigated (L-[(35)S]cystine uptake via system x(c)(-), messenger RNA, and protein expression of the cystine transporter subunit xCT). Glutathione levels in LP-T and peripheral blood T cells were analyzed both spectrophotometrically and by immunofluorescent staining in situ and in vitro.

RESULTS

LP-MO from normal gut, unlike peripheral blood monocytes, are unable to take up cystine, which is due to a deficient expression of the transporter xCT in situ and in vitro. As a consequence, LP-MO do not secrete cysteine. The glutathione content in LP-T from normal gut is <50% of that in autologous peripheral blood T cells. In contrast, in inflammatory bowel disease, CD14(+)CD68(+) LP-MO express xCT and secrete substantial amounts of cysteine upon stimulation, which results in high glutathione levels and full T-cell receptor reactivity in LP-T.

CONCLUSIONS

The antioxidative microenvironment of LP-T in inflammatory bowel disease and the prooxidative microenvironment in normal gut explain the differential T-cell receptor reactivities.

Low intestinal glutamine level and low glutaminase activity in Crohn's disease: a rational for glutamine supplementation?

Intestinal glutamine utilization is integral to mucosal regeneration. We analyzed the systemic and intestinal glutamine status in Crohn's disease (CD) and evaluated the therapeutic effect of glutamine supplementation in an animal model of ileitis. In CD, glutamine concentrations were decreased systemically and in noninflamed and inflamed ileal/colonic mucosa. Mucosal glutaminase activities were depressed in the ileum independent of inflammation but were not different from controls in the colon. In experimental ileitis, oral glutamine feeding prevented macroscopic inflammation, enhanced ileal and colonic glutaminase activities above controls, and normalized the intestinal glutathione redox status. However, glutamine supplementation enhanced myeloperoxidase activity along the gastrointestinal tract and potentiated lipid peroxidation in the colon. In conclusion, glutamine metabolism is impaired in CD. In experimental ileitis, glutamine supplementation prevents inflammatory tissue damage. In the colon, however, which does not use glutamine as its principal energy source, immune enhancement of inflammatory cells by glutamine increases oxidative tissue injury.

Management of a rare case of fulminant hemobilia due to arteriobiliary fistula following total pancreatectomy

Hemobilia is a rare cause of acute upper gastrointestinal bleeding and is often associated with a history of hepatic or biliary tract injury, tumor growth, hepatic artery aneurysm, cholecystitis, or hepatic abscess. We report a case of a 76-year-old patient with massive hemobilia due to intrahepatic bleeding from the segment 8 hepatic artery without evidence of a true aneurysm, abscess, or metastatic disease 4 weeks following pylorus-preserving total pancreatectomy for pancreatic cancer. Gastroduodenoscopy suggested hemorrhage from the duodenojejunostomy but failed to achieve hemostasis, and the patient underwent exploratory laparotomy. It was realized intraoperatively that the bleeding originated from the intrahepatic biliary tract. Bleeding was controlled by blocking the right hepatic bile duct with a Fogarty catheter and subsequent transarterial embolization. Computed tomography did not reveal any local liver or vascular pathology. Retrospectively, the cause of delayed profuse hemobilia was most likely a traumatic intrahepatic pseudoaneurysm following endoscopic bile duct stenting 3 weeks before the pancreatectomy. The reported case is exceptional and of particular interest because of the absence of a typical history or cause of hemobilia, preoperative misleading diagnostic results in an altered anatomic situation, and the operative management to achieve bleeding control in this emergency setting.

Molecular characterisation of non-absorptive and absorptive enterocytes in human small intestine

BACKGROUND AND AIMS

Perturbation of differentiation of the crypt-villus axis of the human small intestine is associated with several intestinal disorders of clinical importance. At present, differentiation of small intestinal enterocytes in the crypt-villus axis is not well characterised.

SUBJECTS AND METHODS

Expression profiling of microdissected enterocytes lining the upper part of crypts or the middle of villi was performed using the Affymetrix X3P arrays and several methods for confirmation.

RESULTS

A total of 978 differentially expressed sequences representing 778 unique UniGene IDs were found and categorised into four functional groups. In enterocytes lining the upper part of crypts, cell cycle promoting genes and transcription/translation related genes were predominantly expressed, whereas in enterocytes lining the middle of villi, high expression of cell cycle inhibiting genes, metabolism related genes, and vesicle/transport related genes was found.

CONCLUSION

Two types of enterocytes were dissected at the molecular level, the non-absorptive enterocyte located in the upper part of crypts and the absorptive enterocyte found in the middle of villi. These data improve our knowledge about the physiology of the crypt-villus architecture in human small intestine and provide new insights into pathophysiological phenomena, such as villus atrophy, which is clinically important.

Carcinoid of the ampulla of Vater

Endocrine neoplasms only rarely occur at the ampulla of Vater, comprising mostly carcinoids and malignant carcinoids, as well as few cases of poorly differentiated endocrine carcinomas (small cell carcinomas). Only 105 cases are reported in the literature, most as single case reports. For many years, the neoplasms of the disseminated neuroendocrine cell system of the gastrointestinal tract have been subsumed as 'carcinoids'. Instead, in the latest World Health Organization (WHO) classification published in 2000, it is recommended to distinguish between (i) well-differentiated endocrine tumors (carcinoids); (ii) well-differentiated endocrine carcinomas (malignant carcinoids); and (iii) poorly differentiated endocrine carcinomas (small cell carcinomas). Patients with carcinoid tumors of the ampulla of Vater are very often free of clinical and laboratory findings that belong to the carcinoid syndrome. Approximately 26% of all patients with carcinoid tumor reported in the literature had neurofibromatosis. Besides endoscopic retrograde cholangiopancreatography, endosonography, computed tomography or magnetic resonance imaging may complete the staging approach of this tumor. The Kausch-Whipple procedure or pylorus-preserving pancreaticoduodenectomy is considered the treatment of choice for ampullary, well-differentiated carcinoids >2.0 cm and for ampullary neuroendocrine carcinomas. However, it should be considered that long-term survival of patients with ampullary carcinoids is also reported after local tumor excision (5-year survival rate of 90%). The dilemma is that the differentiation of neuroendocrine tumors cannot be assessed intraoperatively in most cases. Therefore, considering that the 5-year survival rate in patients with neuroendocrine carcinomas of the ampulla of Vater is very low without radical resection, neuroendocrine tumors of the ampulla of Vater without definite histological differentiation should undergo extended surgery.

Das Abdominaltrauma

Blunt abdominal trauma is much more frequent than penetrating abdominal trauma in Europe. As a consequence of improved quality of computed tomography, even complex liver injuries are increasingly being treated conservatively. However, missed hollow viscus injuries still remain a problem, as they considerably increase mortality in multiply injured patients. Laparoscopy decreases the rate of unnecessary laparotomies in perforating abdominal trauma and helps to diagnose injuries of solid organs and the diaphragm. However, the sensitivity in detecting hollow viscus injuries is low and the role of laparoscopy in blunt abdominal injury has not been defined. If intra-abdominal bleeding is difficult to control in hemodynamically unstable patients, damage control surgery with packing of the liver, total splenectomy, and provisional closure of hollow viscus injuries is of importance. Definitive surgical treatment follows hemodynamic stabilization and restoration of hemostasis. Injuries of the duodenum and pancreas after blunt abdominal trauma are often associated with other intra-abdominal injuries and the treatment depends on their location and severity.

Carcinoid of the ampulla of Vater

Endocrine neoplasms only rarely occur at the ampulla of Vater, comprising mostly carcinoids and malignant carcinoids, as well as few cases of poorly differentiated endocrine carcinomas (small cell carcinomas). Only 105 cases are reported in the literature, most as single case reports. For many years, the neoplasms of the disseminated neuroendocrine cell system of the gastrointestinal tract have been subsumed as 'carcinoids'. Instead, in the latest World Health Organization (WHO) classification published in 2000, it is recommended to distinguish between (i) well-differentiated endocrine tumors (carcinoids); (ii) well-differentiated endocrine carcinomas (malignant carcinoids); and (iii) poorly differentiated endocrine carcinomas (small cell carcinomas). Patients with carcinoid tumors of the ampulla of Vater are very often free of clinical and laboratory findings that belong to the carcinoid syndrome. Approximately 26% of all patients with carcinoid tumor reported in the literature had neurofibromatosis. Besides endoscopic retrograde cholangiopancreatography, endosonography, computed tomography or magnetic resonance imaging may complete the staging approach of this tumor. The Kausch-Whipple procedure or pylorus-preserving pancreaticoduodenectomy is considered the treatment of choice for ampullary, well-differentiated carcinoids >2.0 cm and for ampullary neuroendocrine carcinomas. However, it should be considered that long-term survival of patients with ampullary carcinoids is also reported after local tumor excision (5-year survival rate of 90%). The dilemma is that the differentiation of neuroendocrine tumors cannot be assessed intraoperatively in most cases. Therefore, considering that the 5-year survival rate in patients with neuroendocrine carcinomas of the ampulla of Vater is very low without radical resection, neuroendocrine tumors of the ampulla of Vater without definite histological differentiation should undergo extended surgery.

Intrapulmonal dislocation of a totally implantable venous access device

Background

Totally implantable venous access devices are widely used for infusion of chemotherapy or parenteral nutrition. Device associated complications include technical operative problems, infections, paravasal infusions and catheter or punction chamber dislocation.

Case presentation

We present the case of a 49-year-old patient with the rare complication of a intrapulmonal catheter dislocation of a totally implantable venous access system. Treosulfane for chemotherapy of metastatic breast cancer was infused via the catheter causing instant coughing and dyspnoea which lead to the diagnosis of catheter dislocation. The intrapulmonal part of the catheter was removed under thoracoscopic control without further complications.

Conclusion

Intrapulmonal catheter dislocation is a rare complication of a totally implantable venous access device which can not be avoided by any prophylactic measures. Therefore, the infusion system should be tested before each use and each new symptom, even when not obviously related to the catheter should be carefully documented and evaluated by expert physicians to avoid severe catheter-associated complications.

Potential role of thioredoxin in immune responses in intestinal lamina propria T lymphocytes

Thioredoxin (TRX) is a ubiquitous oxidoreductase with strong co-cytokine, chemoattractant and anti-apoptotic activities. TRX expression was found to be particularly elevated in the intestinal mucosa, where its physiologic function is entirely unknown. Here, we demonstrate a high level of TRX expression in lamina propria T cells (LP-T) as opposed to autologous peripheral blood T lymphocytes (PB-T). Addition of recombinant human TRX (rhTRX) to PB-T enhances TRX gene expression. This autoregulation involves the calcineurin signaling pathway, as rhTRX antagonizes the cyclosporine A (CsA)- and tacrolimus-mediated suppression of TRX gene expression. Similarly, rhTRX reverses the suppression of IL-2 mRNA production by CsA and enhances cytokine production preferentially in prestimulated cells. The differential TRX expression in LP-T versus PB-T may thus contribute to the high-level, CsA-resistant IL-2 production characteristic for CD2-stimulated LP-T. Inversely, inactivation of TRX in LP-T through inhibition of TRX reductase abolishes cytokine gene expression. TRX may play a key role in the specialized intestinal microenvironment in amplifying immediate immune responses of LP-T whenever appropriate costimulation of LP-T is provided.

Inflammatory response after abdominal surgery

Surgical manipulation of the gut elicits an inflammatory cascade within the intestinal muscularis that contributes to postoperative bowel dysmotility. A range of cytokines is sequentially released into the peritoneal fluid following abdominal surgery, their concentrations reflecting the magnitude of surgical trauma. The overproduction of inflammatory mediators might have detrimental effects on organ function and contribute to the enhanced risk of anastomotic leakage in the presence of sepsis. Specific cellular immune functions such as the microbicidal activity of peritoneal phagocytes are depressed after elective surgery, imposing a risk of infectious complications. Laparoscopic surgery decreases the local and systemic production of cytokines and acute-phase reactants, and better preserves peritoneal immunity compared with open surgery. As concluded from animal studies, the gas used for the pneumoperitoneum may possess substantial immunomodulatory activity.

Cytokine/chemokine messenger-RNA expression profiles in ulcerative colitis and Crohn's disease

To define mediator profiles in inflamed and noninflamed areas in inflammatory bowel disease (IBD) we analyzed the expression of 35 messenger-RNAs (mRNAs) encoding cytokines, chemokines, and some related molecules in transmural gut tissues (n=138) from patients with ulcerative colitis (UC), Crohn's disease (CD), and inflammatory and normal controls by real-time quantitative reverse transcription polymerase chain reaction. Using sample collectives with a comparable degree of inflammation, most parameters investigated showed similarly increased mRNA expression levels in both active UC and CD. This included proinflammatory cytokines, but also interferon (IFN) gamma and several IFN-gamma inducible chemokines. Only macrophage inflammatory protein (MIP)-2alpha mRNA was expressed at higher levels in inflamed UC vs. CD. IH revealed that MIP-2alpha protein was produced mainly by intestinal epithelial cells. Importantly, in histologically noninflamed/inactive IBD samples mRNAs for several mediators were significantly enhanced, accompanied by elevated levels of migration-inhibition factor related protein (MRP) 14 transcripts. CD14 positive macrophages were found especially in noninflamed/inactive UC, many of which coexpressed the RFD-7 antigen. Our results indicate a substantial overlap in cytokine/chemokine mRNA expression in UC and CD. Elevated mediator expression is evident in noninflamed/inactive areas in both diseases. Local recruitment of MRP-14 positive leukocytes might contribute to this phenomenon. In inactive UC a phenotypically altered population of macrophages expressing CD14 might play an additional role.

Expression of osteopontin (Eta-1) in Crohn disease of the terminal ileum

BACKGROUND

The causes of Crohn disease (CD) are still regarded as unknown, but impaired mucosal immunoregulation with activation of T-helper-1 (Th-1) cytokine responses is probably involved and may contribute to the morphological changes. We investigated a possible role of osteopontin (Opn) in the pathogenesis of CD. This glycoprotein has been suggested to be involved in the generation of Th-1-type immune responses; moreover, it carries anti-inflammatory activities.

METHODS

Ileal samples from CD patients--both actively inflamed and inactive areas as well as unaffected intestinal specimens from controls (normal ileum)--were investigated by Western blot analysis, immunohistochemistry and in situ hybridization.

RESULTS

In normal gut, Opn was found to be regularly expressed by plasma cells (CD 38) and a subset of lamina propria mononuclear cells (MNC) as well as by intestinal epithelial cells (IEC). In active CD, immunohistochemistry and in situ hybridization analysis revealed a loss of Opn expression by IEC adjacent to ulcerative lesions, whereas especially plasma cells (CD 38) in the vicinity of such lesions were found to express the molecule. In addition, a slight overexpression of Opn protein was found in metaplastic crypts. However, quantitative analysis of total Opn protein in the ileal mucosa of CD patients did not reveal any difference vis-à-vis control tissues.

CONCLUSIONS

The constitutive expression of Opn in normal gut indicates that it is involved in intestinal immune homeostasis. Downregulation of Opn expression in IEC might favour the disintegration of the epithelial barrier. The expression of Opn in lamina propria plasma cells could contribute to disease chronification, probably by affecting cell survival.

[Desmosis coli in adults. Differential diagnosis of chronic constipation]

Desmosis coli is a disturbance of the intramural connective tissue mesh network of the colonic wall which can lead to a hypoperistalsis syndrome with chronic constipation in the absence of any anomaly of the vegetative gut innervation. The condition typically occurs in infants and adolescents; however, as an incomplete form, desmosis coli can also cause chronic constipation in adults, as demonstrated in this case report.

Intraoperative evaluation of big-endothelin plasma levels during liver transplantation in different vascular compartments

Endothelin-1 (ET) is derived from its precursor big-ET, secreted by endothelial cells of multiple origin. The role of ET peptides in the physiological responses after orthotopic liver transplantation (OLT) was investigated. Venous big-ET plasma levels were analysed by RIA in 28 patients before and after OLT. Samples for analysis were taken intraoperatively from 12 patients from the caval, portal and hepatic veins and the radial artery at multiple time points. Highest caval levels were found during the anhepatic period and 60 min after reperfusion, followed by a drop and subsequent increase postoperatively. Highest levels in the hepatic and portal veins were detected during explanation and reperfusion. A different pattern was found in the radial artery. Values during rejection and infection were elevated compared with preoperative and postoperative levels. The heterogeneity of the kinetics points to different sites of ET generation, including liver and splanchnic circulation. It suggests a predominant paracrine secretion mode of ET peptides with various stimuli involved. Big-ET levels could reflect endothelial cell damage, as big-ET is generated intracellularly and biological activity is rather weak.

Thiol-mediated redox regulation of intestinal lamina propria T lymphocytes

Intestinal lamina propria T lymphocytes (LP-Ts) have a markedly low proliferative potential both in vivo and in vitro. Here, we have identified that the capacity of antigen-presenting cells to release cysteine upon receptor-ligand interactions represents a critical parameter for proliferation of LP-Ts. The availability of cysteine is limiting for the intracellular production of glutathione, which in turn is essential for cell cycle progression. When cysteine is provided either directly or by addition of the reducing agent 2-mercaptoethanol to cystine-containing culture medium, proliferation of LP-T is fully restored. Importantly, coculture with peripheral blood monocytes that easily take up cystine, reduce cystine, and secrete cysteine also restores reactivity of LP-Ts to T cell receptor/CD3 stimulation. In marked contrast, lamina propria macrophages lack this capacity to elaborate cysteine, and thereby secure physiological unresponsiveness to antigen exposure in the intestinal microenvironment. The well-documented local recruitment of blood monocytes in inflammatory bowel disease (IBD) may thus represent an important parameter underlying hyperresponsiveness of T cells, an essential component of the pathogenesis of IBD.

Prolonged allograft survival but no tolerance induction by modulating CD28 antibody JJ319 after high-responder rat heart transplantation

BACKGROUND

Allograft rejection depends on T cell immune responses requiring antigen recognition and costimulatory signals through accessory T cell receptors, including CD28. Inhibition of CD28 signaling with a CTLA-4-immunoglobulin (Ig) fusion protein has resulted in immunosuppression and occasional T cell anergy in mouse transplant models, but not in rats. Because this approach also inhibits a potentially tolerizing signal through CTLA-4, selective blockade of CD28 ligation might induce more profound immunosuppression and transplant tolerance.

METHODS

The effects of escalating doses of the rat CD28 monoclonal antibody JJ319 on allograft survival were studied after vascularized heterotopic heart transplantation in a high responder strain combination (DA to Lewis). CD28 antigen modulation and circulating antibody levels were monitored by flow cytometry.

RESULTS

CD28 antibody JJ319 markedly prolonged cardiac graft survival compared with untreated controls (7 days, range: 6-8). A strictly dose-dependent increase in median graft survival time was demonstrated with a maximum of 36 days (range: 30-40; p <0.001) after the administration of 8 x 1 mg JJ319 i.p. (days -1 to +6 before/after transplantation). However, indefinite graft survival and tolerance could not be induced by JJ319 treatment. At the maximal dose, flow cytometry showed complete down modulation of the CD28 receptor for 10-14 days without T cell depletion in close temporal relation to antibody presence in serum. In vitro, CD28-modulated T cells showed significantly reduced responses to activation.

CONCLUSIONS

CD28 antibody JJ319 induces profound immunosuppression after rat heart transplantation, however without development of transplant tolerance. The underlying mechanism seems to be receptor modulation during primary alloantigen recognition. While still potentially applicable clinically, there are no qualitative or quantitative differences to the treatment with CTLA-4/lg or the blockade of CD2 or LFA-1, as reported elsewhere. Thus, a CD28-modulating approach seems not to allow therapeutic exploitation of a tolerizing signal delivered by CTLA-4 but may still be clinically applicable, especially in combined immune interventions.

Differential immunosuppressive activity of monoclonal CD2 antibodies on allograft rejection versus specific antibody production

CD2 is a co-stimulatory receptor involved in T cell activation. Here we report on immunosuppressive effects of three mouse CD2 monoclonal antibodies (OX34, OX54, OX55) directed against non-overlapping epitopes of the rat CD2 receptor on various modes of T cell activation in vitro and in vivo. Although non-ligand-blocking OX54 and OX55, in concert, activated T cells through CD2 in vitro, they individually suppressed the mixed lymphocyte reaction (MLR) and significantly prolonged allograft survival after rat heart transplantation in vivo. Phenotype analysis revealed that OX55 significantly down-modulated CD2 in vivo, whereas OX54 depleted T cells. Graft rejection coincided with re-expression of CD2 and clearance of OX55 from serum, whereas T cell depletion by OX54 outlasted the period of graft survival. The most suppressive antibody, OX34, down-modulated CD2 and inhibited T cell activation through the TCR or CD2 and the MLR and prolonged median allograft survival time from 7 days in controls to 45 days in the absence of any additional treatment. Graft survival was clearly dose dependent and correlated with the duration of CD2 down-modulation and the presence of circulating CD2 antibody in serum. Importantly, the specific antibody production to a T cell-dependent antigen as demonstrated by immunization with keyhole limpet hemocyanin in vivo remained unaffected after treatment with OX34. These results demonstrate the pivotal role of CD2 signaling in mediating allogeneic immune reactions after vascularized organ transplantation while allowing specific humoral immune responses in vivo.

Impairment of intestinal glutathione synthesis in patients with inflammatory bowel disease

BACKGROUND

Reactive oxygen species contribute to tissue injury in inflammatory bowel disease (IBD). The tripeptide glutathione (GSH) is the most important intracellular antioxidant.

AIMS

To investigate constituent amino acid plasma levels and the GSH redox status in different compartments in IBD with emphasis on intestinal GSH synthesis in Crohn's disease.

METHODS

Precursor amino acid levels were analysed in plasma and intestinal mucosa. Reduced (rGSH) and oxidised glutathione (GSSG) were determined enzymatically in peripheral blood mononuclear cells (PBMC), red blood cells (RBC), muscle, and in non-inflamed and inflamed ileum mucosa. Mucosal enzyme activity of gamma-glutamylcysteine synthetase (gamma GCS) and gamma-glutamyl transferase (gamma GT) was analysed. Blood of healthy subjects and normal mucosa from a bowel segment resected for tumor growth were used as controls.

RESULTS

Abnormally low plasma cysteine and cystine levels were associated with inflammation in IBD (p < 10(-4)). Decreased rGSH levels were demonstrated in non-inflamed mucosa (p < 0.01) and inflamed mucosa (p = 10(-6)) in patients with IBD, while GSSG increased with inflammation (p = 0.007) compared with controls. Enzyme activity of gamma GCS was reduced in non-inflamed mucosa (p < 0.01) and, along with gamma GT, in inflamed mucosa (p < 10(-4)). The GSH content was unchanged in PBMC, RBC, and muscle.

CONCLUSIONS

Decreased activity of key enzymes involved in GSH synthesis accompanied by a decreased availability of cyst(e)ine for GSH synthesis contribute to mucosal GSH deficiency in IBD. As the impaired mucosal antioxidative capacity may further promote oxidative damage, GSH deficiency might be a target for therapeutic intervention in IBD.

Modulation of the CD2 receptor and not disruption of the CD2/CD48 interaction is the principal action of CD2-mediated immunosuppression in the rat

CD48, the murine homolog of human CD58, binds to CD2 in rats and mice. Whereas inhibition of CD2 signaling leads to profound immunosuppression, no information is available on CD48-targeted therapy in the rat. We could show that anti-CD2 treatment (OX34) efficiently inhibited TCR-driven as well as CD2-mediated proliferation, whereas blocking of ligand binding (OX45) remained completely uneffective. Inhibition of allogeneic MLR by OX45 turned out to be due to induction of unspecific suppressive mechanisms. In vivo, OX45 failed to prolong rat heart allograft survival in contrast to that seen with OX34. Grafts were rejected despite persistent and complete downmodulation of CD48 on lymphocytes without any cell depleting effect, rendering receptor/ligand interactions physically impossible. Combined application of CD2 and CD48 mAb did not enhance immunosuppression induced by CD2 mAb alone. Provided that there is no alternative CD2 ligand in the rat, we conclude that CD2-directed immunotherapy is mediated by suppressive events induced by modulation of the CD2 receptor ("negative signaling") rather than by mere disruption of the CD2-CD48 interaction.

[Perspectives of immunosuppressive therapy]

The goal of immunosuppressive therapy in organ transplantation is the achievement of transplant-specific immune tolerance. Elucidation of the molecular basis of the functions of human lymphocytes is a step towards the development of novel, more specific and less harmful measures for clinical immune intervention.

Prolonged allograft survival by the inhibition of costimulatory CD2 signals but not by modulation of CD48 (CD2 ligand) in the rat

The CD2 receptor is an important costimulatory molecule in T cell activation. Its ligand CD48 in rodents is supposed to be a homologue of human CD58, because of its similarities in structure and distribution. We evaluated the immunosuppressive activity of CD2/CD48-directed therapy in vitro and in vivo for the efficacy in prolonging rat heart allograft survival in a high responder transplant model. CD2-directed monoclonal antibody (mAb) therapy significantly prolonged median survival time to 45 days (P < 0.001). Suppression was mediated by down-modulation of CD2 below 20% on lymph node cells without considerable cell depletion. In contrast, CD48 mAb could not prolong graft survival. Rejection occurred in the presence of complete CD48 modulation and, therefore, despite disruption of the CD2-CD48 interaction. CD48 mAb failed to inhibit lymphocyte activation via a mitogenic pair of CD2 mAbs and inhibited mixed lymphocyte reaction (MLR) only by an unspecific mechanism. In conclusion, our results suggest a negative regulatory signal transduction by inhibitory CD2 mAbs and argue against a pivotal role of mere disruption of the CD2-CD48 interaction in CD2-mediated immunosuppression.

Soluble thrombomodulin--a marker of reperfusion injury after orthotopic liver transplantation

Thrombomodulin is an endothelial cell membrane protein that is released into the blood in soluble forms (soluble thrombomodulin [sTM]) in response to endothelial cell damage. We evaluated intraoperative sTM as a marker of reperfusion injury in 29 liver transplant recipients using an ELISA. Preoperative sTM levels were significantly elevated, as compared with healthy control subjects (75 +/- 61 ng/ml vs. 17 +/- 10 ng/ml; P < 0.001) and remain unchanged at the end of the anhepatic phase (58 +/- 40 ng/ml). There is an increase to 194 +/- 182 ng/ml 3 min after reperfusion (P < 0.001). Post-reperfusion sTM levels correlate significantly with the early liver enzyme release (aspartate transaminase) (P < 0.001). Patients with pronounced reperfusion injury (postreperfusion arterial sTM > 138 ng/ml, n = 16) present significantly higher maximum aspartate transaminase levels within the first 24 postoperative hr, as compared with patients with less reperfusion injury (arterial sTM < 138 ng/ml, n = 12) (P = 0.001). Released sTM is derived from the graft, since patients with pronounced reperfusion injury present significantly higher sTM levels in the hepatic vein 3 min after reperfusion compared with the portal vein (P < 0.001) and artery (P = 0.025), respectively. In patients with higher reperfusion injury, we found significantly more adherent intrasinusoidal granulocytes in the liver biopsy taken 1 hr after reperfusion (P = 0.006), indicating an interrelation of endothelial damage and the important phenomenon of "leukocyte sticking" in reperfusion injury. Thus the postreperfusion increase of sTM as a marker of reperfusion injury correlates with the early liver enzyme release and the accumulation of intrasinusoidal granulocytes.

Expression of receptors for advanced glycation end products in peripheral occlusive vascular disease

The cellular interactions of advanced glycation end products (AGEs), which have been hypothesized to contribute to the development of vascular lesions, occur, at least in part, through their binding to a novel integral membrane protein, the receptor for AGEs (RAGE). Studies of human vascular segments show that endothelial RAGE expression at the antigen and mRNA level was variable and usually at low levels in samples from healthy individuals. In contrast, patients with a range of peripheral occlusive vascular diseases, with or without underlying diabetes, demonstrated prominent enhancement of endothelial RAGE expression. Smooth muscle cells and nerves in the vessel wall showed constitutively high levels of RAGE expression that were unchanged with aging (from 1 to 92 years) or by the presence of vascular disease. These data suggest that RAGE is likely to have ligands other than AGEs, and that multiple factors in addition to AGEs impact on its expression. Taken together, our findings suggest that RAGE may contribute to the pathogenesis of a range of vascular disorders.

[Effect of blood transfusions on rate of recurrence of Crohn disease]

The effect of perioperative blood transfusions on recurrence has been investigated in 261 patients with Crohn's disease who underwent a "curative" operation since 1981. Reoperations were necessary with a rate of approximately 3% per year. By Kaplan-Meier-analysis no difference could be detected between 120 patients with transfusion and 141 without (p = 0.407, log rank test). Statistical analysis of potentially interfering covariables revealed a significant effect of age and type of operation on postoperative recurrences. Even after stratification for these parameters it was impossible to confirm the protective influence of transfusions reported by others. However, in some subgroups there was a trend towards an association of blood transfusions with earlier reoperations.