Improving biliary stent patency by the use of stent coating - a prospective randomized porcine study.

BACKGROUND: Endoscopic stenting of the bile duct is a standard procedure for almost 35 years. In the case of long-term stenting occlusion of the stent is a major concern. Therefore optimizing biliary stents with respect to their patency is of great importance. We tested in an in animal study if coating of self-expanding metal stents with hydrophobin alone or hydrophobin with heparin reduces stent clogging as there were promising results in an in vitro study with this approach. MATERIAL AND METHODS: In a randomized prospective animal study we implanted self-expanding metal stents either native or coated with hydrophobin alone or coated with hydrophobin and heparin into the bile duct of 15 pigs. After a survival period of 6 weeks we measured which part of the stent surface (%) was covered with clogging material using a commercially available image editing program on scanning electron microscopic images. RESULTS: We found no differences between the native self-expanding metals stents and those coated with hydrophobin alone or hydrophobin and heparin. CONCLUSION: There are important differences in the clogging process between in vitro and in vivo models. Coating with hydrophobin with or without heparin is not able to inhibit the clogging process in an animal model.

Frequency, histopathological findings, and clinical significance of cervical heterotopic gastric mucosa (gastric inlet patch): a prospective study in 300 patients.

The frequency and clinical significance of heterotopic gastric mucosa in the upper esophagus is not sufficiently known. Heartburn or dysphagia could result from mucin and/or acid production in this area. We undertook a prospective study in 300 patients with special attention of the endoscopist to this area. Moreover, clinical symptoms were determined by questionnaire before performing endoscopy. A total of 33/300 (11%) of patients had at least one histologically proven gastric inlet patch without gender or age preference. In 20/33 (61%) cases, the heterotopic gastric mucosa was classified as mixed type, in 8/33 (24%) as oxyntic, and in 5/33 (15%) as mucoid. Helicobacter pylori was present in none of the cases. There was no significant association to the presence of a hiatal hernia, reflux esophagitis, Barrett's esophagus, or gastric/duodenal ulcer. Moreover, there was no association to the reported grade of heartburn in the upper or lower part of the esophagus, recurrent hoarseness, or dysphagia. When thoroughly performed, heterotopic gastric mucosa is a quite frequent finding in endoscopy of the upper gastrointestinal tract. The presence of this gastric mucosa in the upper third of the esophagus seems to be rarely the cause of clinical symptoms and little prone to complications.

Gastric fundic gland polyps and colonic polyps - is there a link, really?

BACKGROUND AND AIM: A retrospective analysis of endoscopic investigation was carried out. Gastric fundic gland polyps occur in patients with familial adenomatous polyposis. The aim of our study was to investigate if colonic polyps is present and related to gastric fundic gland polyps. PATIENTS AND METHODS: A 6 years retrospective analysis was carried out. At baseline upper gastrointestinal endoscopy, gastric fundic gland polyps were diagnosed in patients suffered from intestinal bleeding. Subjects received a colonoscopy additionally. A total of 500 patients were enrolled into study: 250 fulfilled the diagnostic criteria for gastric fundic gland polyps and 250 age and sex matched served as controls. RESULTS: Colonic cancer was more frequently observed in 39 (15.5%) patients who met the criteria of gastric fundic gland polyps as compared to 23 (9.2 %) patients of the controls (p <0.05). Patients with gastric fundic gland polyps tended to have more often colonic polyps 122 vs. 111, but these differences were not statistically significant. CONCLUSION: The prevalence of colonic cancer was elevated in patients with gastric fundic gland polyp. Furthermore, this relationship did not differ significantly according to occurrence of colonic polyps. Even tough colonoscopy is prophylactic in preventing colonic cancer; the use of colonoscopy should be encouraged in patients with gastric fundic gland polyps.

Prospective nonrandomized comparison of two modes of argon beamer (APC) tumor desobstruction: effectiveness of the new pulsed APC versus forced APC.

BACKGROUND AND STUDY AIM: Argon plasma coagulation (APC) has become an established noncontact method of tumor palliation in a variety of locations. The present prospective study evaluated a new APC system (APC-2) using amplified power settings and different application modes, such as intermittent energy delivery (pulsed APC) in comparison with the conventional technique (forced APC). PATIENTS AND METHODS: A total of 100 patients with esophageal, gastric, or rectal tumors were alternately (but not randomized) enrolled and treated with either pulsed APC (n = 46) or forced APC (n = 54). Parameters to assess the palliative effect were: amount of lumen restoration ((1/3), (2/3), complete), objective planimetry, stenosis length, treatment time, and number of APC sessions. RESULTS: Overall response rate was similar in both groups (pulsed 83 %, forced 87 %), the same was found in the subgroups with different amounts of lumen restoration and for the other objective parameters. However, the tumor debulking effect was achieved in a significantly shorter median treatment time with forced compared with pulsed APC (13.6 vs. 18.2 minutes, P = 0.03), with a similar number of treatment sessions in both groups. Complications also occurred with similar frequency in both groups. CONCLUSIONS: There was no significant difference in overall local tumor response between the two modes of APC application. However, data from this nonrandomized study suggest a faster achievement of response with forced APC. A combination of both modes may be superior.

Does Cytokeratin7/20 immunoreactivity help to distinguish Barrett's esophagus from gastric intestinal metaplasia? Results of a prospective study of 75 patients.

Barrett's esophagus is a recognized risk factor for the development of esophageal dysplasia and carcinoma. Unfortunately, gastric incomplete intestinal metaplasia arising in Short Segment Barrett's esophagus can be indistinguishable histologically on hematoxylin/eosin stains. Distinct patterns of CK 7 and CK 20 immunohistochemical expression have been demonstrated to be both highly sensitive and specific for Barrett's esophagus, but have not been found in gastric metaplasia. The aim of our study was to test whether immunostaining with CK 7/20 helps to distinguish between Barrett's epithelium and gastric incomplete metaplasia. Cases of long segment Barrett's esophagus, short segment Barrett's esophagus, and cases with a normal gastroesophageal junction, as well as specimens with gastric antral intestninal metaplasia, were examined: three patterns were defined. Barrett's pattern (superficial CK 20 staining; superficial and crypt CK 7 staining); gastric pattern (superficial and crypt staining of both markers); other patterns (different from Barrett and gastric types). Seventy-five patients were enrolled in this study, 26 with long segment Barrett's esophagus, 21 with short segment esophagus, 13 with intestinal metaplasia of the cardia, and 18 with antral intestinal metaplasia. The Barrett pattern showed a high specificity of 97%, but a sensitivity of only 30% in patients with short segment Barrett esophagus. Our results do not confirm the hypothesis that CK 7/20 immunostaining can be used for a reliable differentiation between incomplete intestinal metaplasia and Barrett's epithelium.

[CEUS--a robust method in daily clinical practice? A six month retrospective analysis]. / Ist die Kontrastmittelsonographie im klinischen Alltag eine robuste Methode? Eine retrospektive Analyse über 6 Monate.

BACKGROUND: CEUS is a relatively new imaging method with growing use and broadening applications. It shows excellent accuracy with high negative and positive predictive values under study conditions. It is not well known, whether the study results can be reproduced in daily clinical practice. METHODS: Retrospective analysis of all consecutive CEUS-exams at our institution during a six month period. RESULTS: 68% of CEUS-exams were of the liver. 83% (197 exams) concerned the characterisation of focal lesions. 95% of focal lesions could be clarified via CEUS. In 44% of the exams, CEUS changed the diagnosis of B-mode-US, in 74% of exams, CEUS was the final imaging method. We found a 64% concordance to cross sectional imaging and a 77% concordance to histology, when available. CONCLUSION: CEUS performance in daily clinical practice is comparable to controlled study conditions. CEUS is therefore a robust imaging method.

[Contrast-enhanced ultrasound of focal fatty sparing]. / Kontrastmittelsonografie einer zonalen Minderverfettung.

HISTORY AND CLINICAL FINDINGS: A 52-year-old man went to his family doctor because of nonspecific abdominal complaints. The physical findings were unremarkable. The abdominal ultrasound unexpectedly showed a nonhomogeneous focal fatty sparing around the gallbladder fossa, which was the reason why the patient was referred for contrast-enhanced ultrasonography (CEUS). INVESTIGATIONS: The native ultrasound showed focal fatty sparing around the gallbladder fossa, while the CEUS demonstrated a high-flow hemangioma with subsequent peritumoral fatty sparing caused by arterioportal shunts. MRI of the liver confirmed the hemangioma. CONCLUSION: Focal fatty sparing which is nonspecific and not typical in its localization should be carefully investigated, because it could be a peritumoral fatty sparing. The same is true for nonhomogeneous fatty sparing at a typical position. Special attention should be given to signs of shunting. The CEUS in low-MI mode provides a dynamic real-time examination and is the method of choice in this situation.

Optimizing biliary stent patency by coating with hydrophobin alone or hydrophobin and antibiotics or heparin: an in vitro proof of principle study.

PURPOSE: Although a wide range of biliary plastic and metal stents is on offer nowadays, the ideal cost-effective stent that functions permanently and that is easy to handle regarding its exchange is still not available. Therefore we tested in an in vitro model if the coating of plastic stents with hydrophobin alone or with hydrophobin and antibiotics or heparin in combination leads to an inhibition of the clogging process. METHODS: We coated commercially available biliary plastic stents with hydrophobin alone, as well as with hydrophobin and antibiotics or heparin in combination. After an incubation period of 28 days in human bile, we examined the stents by scanning electron microscopy to see whether the clogging material on its surface was reduced. RESULTS: Coating of plastic stents with hydrophobin led to a reduction in the amount of adherent material on the surface of the stents. Coupling of ampicillin/sulbactam or levofloxacin did not lead to a further reduction of the clogging material, whereas coupling with highly concentrated heparin did reduce the adherent material. CONCLUSIONS: The coating of biliary plastic stents with hydrophobin or with hydrophobin and heparin in combination seems to be a promising option to delay the clogging process.

[Benign non-peptic esophageal stenosis: causes, treatment and outcome in routine clinical practice]. / Ursachen, Therapie und Verlauf benigner, nicht-peptischer Osophagusstenosen in der klinischen Routine.

BACKGROUND AND OBJECTIVE: Benign non-peptic esophageal stricture (BNES) is a rare condition in routine clinical practice. The distribution of different diseases causing BNES is not known and the efficacy and safety of endoscopic treatment in this setting has not been established. PATIENTS AND METHODS: All patients with BNES undergoing endoscopic treatment at our hospital between 2000 and 2006 were assessed retrospectively and questioned by telephone. RESULTS: A total of 26 patients with BNES had been treated at our institution (median age 65 years, range 15-90) during this period. Common causes were esophageal intramural pseudodiverticulosis (n=11), caustic ingestion (n=4) and eosinophilic esophagitis (n=3). Other causes were Schatzki (-Gary) ring, incomplete esophageal atresia, heterotopic gastric mucosa, mucosal pemphigoid, spondylotic caused stenosis, epiphrenic diverticulum, unspecified stenosis. Median time until definitive diagnosis was five-and-a-half years. 20 patients were treated by bougienage, 3 were treated by balloon dilatation, 2 by medication alone and one patient did not require treatment. Lasting successful treatment was achieved in all There were no treatment-related complications. CONCLUSIONS: Benign, non-peptic esophageal stricture is a rare condition in routine clinical practice and can be caused by various diseases. Time to exact diagnosis is often very long. When the underlying diagnosis is clear, excellent results of symptomatic endoscopic therapy can be achieved in a gastroenterological center.

A comparative scanning electron microscopic study of biliary and pancreatic stents.

BACKGROUND: Little is known about the similarities and differences in the clogging process of biliary and pancreatic stents. The aim of the study was to elucidate this process using scanning electron microscopy. MATERIALS AND METHODS: Scanning electron microscopy was performed in a consecutive series of 18 biliary and 10 pancreatic endoprostheses. The indication for stenting in the 18 patients (13 men, 5 women) with biliary stents was malignancy (n = 11), benign bile duct stenosis (n = 5), and biliary obstruction by bile duct stones (n = 2). The indication for stenting in the 10 patients (8 men, 2 women) with pancreatic stents was chronic pancreatitis with or without stenosis of the pancreatic duct. RESULTS: The scanning electron microscopy study revealed a quite uniform pattern of the clogging material in biliary and pancreatic stents. The clogging material seemed to adhere to the inner stent surface by numerous tiny threads. The clogging material itself was also stabilized by tiny threads. CONCLUSIONS: The occurrence of the tiny threads constitutes the central point in the clogging process in biliary and pancreatic stents. Inhibiting the formation of these threads or at least preventing adhesion to the inner stent surface might be the best option to improve stent patency.

A rare cause of distal bile duct stenosis.

INTRODUCTION: In a patient with a distal bile duct stenosis a definite diagnosis could not be made preoperatively. DISCUSSION: The histologic evaluation of the surgical resection specimen revealed infiltration of the pancreatic head and the distal bile duct by breast tumor cells. CONCLUSION: The metastasis was the only tumor manifestation after mastectomy 12 years ago.

[In-hospital mortality of acute hemorrhage of esophageal/fundus varices: an analysis of blood glucose level and other risk factors in 99 consecutive patients]. / Krankenhausletalität der akuten Osophagus-/Fundusvarizenblutung: Eine Analyse des Aufnahmeblutzuckers und weiterer Faktoren bei 99 Patienten.

BACKGROUND AND OBJECTIVE: The analysis of risk factors in acute variceal bleeding may help to optimize patient management. The influence of hyperglycemia, which has been demonstrated for different diseases in the intensive care unit, has not been investigated for acute variceal bleeding. PATIENTS AND METHODS: We reviewed a consecutive series of 99 patients with acute variceal bleeding treated in our clinic between 1996 and 2005. Possible risk factors leading to death during the hospital stay were analysed. RESULTS: The in-hospital mortality was increased in patients with a raised Child-Pugh index of cirrhosis, active bleeding during emergency endoscopy and an elevated creatinine concentration. The baseline blood glucose value was of no prognostic value. CONCLUSION: Even in the current management of variceal bleeding the Child-Pugh index for cirrhosis as well as and active bleeding during emergency endoscopy remain decisive factors in the short-term prognosis. In contrast to other diseases occurring in the intensive care unit, hyperglycemia or insulin resistance plays no significant role.

[Space-occupying lesions in the liver: incidence of adenocarcinoma metastases of unknown primary site]. / Unklare hepatische Raumforderungen: Häufigkeit von Adenokarzinom-Metastasen eines unbekannten Primärtumors.

BACKGROUND AND OBJECTIVE: The diagnostic approach to newly detected space-occupying lesions in the liver can be difficult and a histogenetic classification of the primary tumor is impossible in some cases. Such cases of metastatic disease without a detectable primary tumor are classified as cancer of unknown primary site (CUP). The incidence of this diagnosis depends on the clinical and histochemical methods used. It was the main aim of this study to analyze the true incidence of adenocarcinoma metastases of the liver with an unknown primary cancer after application of a standardized protocol of clinical and immunhistochemical diagnostic tests and a long-term follow-up. PATIENTS AND METHODS: Between January 2000 and January 2003 127 consecutive patients underwent diagnostic ultrasound-guided biopsy of a space-occupying lesion in the liver. Based on the histopathology and immunochemistry a well defined and individually adapted diagnostic algorithm was employed (endoscopy, imaging). RESULTS: 44 females and 83 males, median age 66.8 years, were enrolled into the study. Primary tumors of the liver were found in 21 cases and non-hepatocellular tumors (metastases) were documented in 106 patients, 82 of the latter (77%) had metastases of an adenocarcinoma. The further diagnostic approach was based on histochemistry, immunhistochemistry and imaging techniques, making possible a full diagnosis of primary tumor in a further 59 (72%) cases. Thus the incidence of an adenocarcinoma of the liver of unknown primary site was 23 of 127 cases (18%). CONCLUSIONS: Although there is a wide variety of modern diagnostic methods today, the histogenetic classification of hepatic metastases is not always possible. However, in the last few years diagnostic advances have occurred based on modern immunhistochemical methods. This immunhistochemical definition has made it possible to avoid an oppressive "overdiagnosis" and offer patients early and appropriate therapeutic options.

[The management of bleeding ulcers]. / Management der Ulkusblutung.

Bleeding peptic ulcers are responsible for about half of all upper gastrointestinal hemorrhages, one of the most frequent gastroenterological emergencies. In its pathogenesis, infection with Helicobacter pylori and the use of ulcerogenic drugs play a dominant role. Endoscopy has to be performed urgently when a decline in hemoglobin and/or hemodynamic instability occurs. The indications for local endoscopic therapy depend on the Forrest criteria, which include bleeding and the presence or absence of a blood clot or visible vessel. Local endoscopic therapy comprises injections and mechanical or thermal procedures. The efficacy of these procedures has been demonstrated. Additionally, proton pump inhibitors are administered. The prognosis for bleeding ulcers depends on the endoscopic findings as well as the age and comorbidity of the patients.

[Space-occupying lesion of the pancreas--how frequently not due to a suspected ductal adenocarcinoma?]. / Solide Pankreasraumforderung -- Wie häufig ist die erste Assoziation "duktales Adenokarzinom" falsch?

In patients with a space-occupying lesion of the pancreas at first a primary ductal adenocarcinoma is considered as the cause. Other tumours or metastases are assumed to occur very rarely. Therapy and prognosis of other pancreas tumours differ from therapy and prognosis of a primary ductal adenocarcinoma. We therefore examined the question of how frequently a space-occupying lesion of the pancreas was not due to a ductal adenocarcinoma in our case materials. Retrospectively 70 patients who had undergone a percutaneous puncture of a space-occupying mass of the pancreas under ultrasonographic control were included in the study (34 women, 36 men). In 62 patients a clear histological diagnosis was possible on the basis of the biopsy. In 53 cases (76 %) a primary adenocarcinoma of the pancreas could be diagnosed. In 5 patients (7 %) these masses turned out to be metastases of a previously known malignant tumour disease (2 x mammary carcinoma, 2 x gastric carcinoma, 1 x sigmoid carcinoma). Other tumours could be detected in 4 cases (6 %) including a tuberculoma, an endocrine tumour, a fusocellular sarcoma with partial neurogenic differentiation and a large-cell and pleomorphic-cell anaplastic, partly sarcomatoid carcinoma. In patients with a space-occupying lesion of the pancreas, tumours other than a ductal adenocarcinoma are not rare. In particular, in cases of a previously known malignant tumour disease a space-occupying lesion of the pancreas can also turn out to be a metastasis. Every other individual tumour entity is rare. Other tumour entities at large, however, are found in daily routine. The preoperative biopsy of space-occupying lesions of the pancreas, therefore, still has a clinical importance for the further therapy planning.