Frank Serge Lehmann

Calretinin as a Marker for Cardiac Myxoma Diagnostic and Histogenetic Considerations

To study the usefulness of calretinin as an immunohistochemistry marker in the diagnosis of cardiac myxoma (CM) and the origin of myxoma cells, we examined 24 CMs and 9 fetal hearts with immunohistochemical methods on formalin-fixed paraffin-embedded tissues. We compared 24 CMs with 10 mural thrombi, 6 jaw myxomas, and 2 papillary fibroelastomas. Calretinin expression was identified in 100% of CMs and was negative in all cases of mural thrombi, jaw myxoma, and papillary fibroelastoma. Calretinin expression by the neoplastic cells in CM was strong and diffuse and had a cytoplasmic and a nuclear pattern. Calretinin expression in fetal hearts was found in autonomic ganglia cells in the subepicardial tissue of the atria and atrial appendages, along the interatrial and atrioventricular sulci, and in the atrial septum. Results clearly indicate that calretinin can be used as a marker for the diagnosis of CM and that it is a powerful tool for the differential diagnosis, most importantly with mural myxoid thrombi. Furthermore, the positive expression of calretinin by the autonomic neurons in the fetal heart and CM supports the concept that myxoma cells may originate from endocardial sensory nerve tissue.

Value of fecal calprotectin in the evaluation of patients with abdominal discomfort: an observational study

BackgroundThe evaluation of patients with abdominal discomfort is challenging and patient selection for endoscopy based on symptoms is not reliable. We evaluated the diagnostic value of fecal calprotectin in patients with abdominal discomfort.MethodsIn an observational study, 575 consecutive patients with abdominal discomfort referred for endoscopy to the Department of Gastroenterology & Hepatology at the University Hospital Basel in Switzerland, were enrolled in the study. Calprotectin was measured in stool samples collected within 24 hours before the investigation using an enzyme-linked immunosorbent assay. The presence of a clinically significant finding in the gastrointestinal tract was the primary endpoint of the study. Final diagnoses were adjudicated blinded to calprotectin values.ResultsMedian calprotectin levels were higher in patients with significant findings (N = 212, median 97 μg/g, IQR 43-185) than in patients without (N = 326, 10 μg/g, IQR 10-23, P < 0.001). The area under the receiver operating characteristics curve (AUC) to identify a significant finding was 0.877 (95% CI, 0.85-0.90). Using 50 μg/g as cut off yielded a sensitivity of 73% and a specificity of 93% with good positive and negative likelihood ratios (10.8 and 0.29, respectively). Fecal calprotectin was useful as a diagnostic parameter both for findings in the upper intestinal tract (AUC 0.730, 0.66-0.79) and for the colon (AUC 0.912, 0.88-0.94) with higher diagnostic precision for the latter (P < 0.001). In patients > 50 years, the diagnostic precision remained unchanged (AUC 0.889 vs. 0.832, P = 0.165).ConclusionIn patients with abdominal discomfort, fecal calprotectin is a useful non-invasive marker to identify clinically significant findings of the gastrointestinal tract, irrespective of age.

The role and utility of faecal markers in inflammatory bowel disease

Crohn’s disease and ulcerative colitis are characterized by periods of symptomatic relapse and remission. Diagnosis and assessment of inflammatory bowel disease has so far been based on clinical evaluation, serum parameters, radiology and endoscopy. Faecal markers such as calprotectin or lactoferrin have emerged as new diagnostic tools to detect and monitor intestinal inflammation. This review focuses on their potential clinical applications and limitations in the management of inflammatory bowel disease.

Progressive development of diffuse liver hemangiomatosis

Diffuse liver hemangiomatosis is extremely rare. The etiology and natural history of the disease are unknown. It is also unclear whether tumor growth is induced or modulated by drug therapy. Tumor recurrence after ablative therapy has not been described in patients with diffuse liver hemangiomatosis. Diffuse hemangiomatosis of the left hepatic lobe was suspected in a 35-year-old woman by ultrasonography, CT and hepatic arteriography, and confirmed by laparotomy and biopsies. The patient denied any drug or estrogen use. The tumor was removed by left hepatectomy. Two and six years later, the patient was again hospitalized with progressive tumor growth into the right hepatic lobe. Although diffuse liver hemangiomatosis is a rare disease, its diagnosis should be considered in patients with progressive tumor growth in one or both hepatic lobes. The absence of drug intake or estrogen use does not exclude the diagnosis.

New Molecular Targets for Treatment of Peptic Ulcer Disease

Most patients with peptic ulcer disease are currently treated with proton pump inhibitors or histamine H2 receptor antagonists. The long-term use of these compounds has been associated with two potential problems. Firstly, proton pump inhibitors may induce enterochromaffin-like (ECL) cell hyperplasia. Secondly, ulcers may relapse despite maintenance therapy with histamine H2 antagonists. This has been the rationale for the development of new antisecretory agents, including antagonists against gastrin and gastrin releasing peptide (GRP), as well as ligands to histamine H3 receptors.Several potent, high affinity cholecystokinin (CCK)-2 receptor antagonists have recently been identified such as L-365260, YM-022, RP-73870, S-0509, spiroglumide and itriglumide (CR-2945). Current data suggest that they all have antisecretory and anti-ulcer effects. In addition to reducing acid production, CCK-2 receptor antagonists may possibly also accelerate gastric emptying, a combination of functions which could potentially be beneficial in patients with functional dyspepsia.Receptors for bombesin and its mammalian counterpart GRP have been localised in the brain, spinal cord and enteric nerve fibres of the gut as well as on secretory cells and smooth muscle cells of the intestinal tract. Current data clearly indicate that endogenous GRP is involved in the regulation of basal and postprandial acid secretion. However, at this stage it is not clear whether GRP agonists or GRP antagonists can be developed into useful drugs. The peptide has a wide range of biological effects and it is likely that analogues of GRP or antagonists of the peptide affect not only gastric acid secretion but also induce considerable side effects.Histamine plays a central role in the stimulation of acid secretion. After their detection in the brain, H3 receptors have been identified in a variety of tissues including perivascular nerve terminals, enteric ganglia of the ileum and lung, and ECL cells. Despite many studies, the role of H3 receptors in the regulation of gastric acid secretion is still unclear. Controversial data have been presented, and study results largely depend on the species and experimental models.It seems unlikely that proton pump inhibitors or H2 receptor antagonists will be replaced in the near future by new antisecretory agents. The current shortcomings of the new compounds include mainly their reduced clinical effectiveness and pharmacological limitations. However, the development of these new antisecretory compounds provides interesting tools to assess the physiological and pharmacological role of different receptors within the gastrointestinal tract. The use of CCK-2 receptor antagonists in patients with functional dyspepsia and Zollinger-Ellison syndrome should be examined in randomised, controlled trials.

Comparison of stool immunoassay with standard methods for detecting Helicobacter pylori infection

Helicobacter pylori is the cause of type B gastritis and associated with peptic ulcer disease. Various methods are available for detecting H pylori , but all have limitations.1 H pylori infection can be diagnosed by tests requiring endoscopy (rapid urease test, histology, culture) and by non-invasive tests (carbon-13 urea breath test, serology, stool tests). The urea breath test is currently the most important test for follow up after H pylori treatment.1 Serology is widely used for screening patients for H pylori infection; it has a good sensitivity, is fast, and relatively inexpensive.1 However, the urea breath test is expensive and requires specialised equipment, and serological tests cannot be used after H pylori treatment and may have a lower specificity.nnMost patients infected with H pylori are treated by general practitioners, who need an easy …

Effect of EpCAM, CD44, CD133 and CD166 expression on patient survival in tumours of the ampulla of Vater

Background Carcinomas of the Vaterian system are rare and presumably arise from pre-existing adenomas. According to the cancer stem cell (CSC) hypothesis, only a small subset of tumor cells has the ability to initiate and develop tumor growth. In colorectal cancer, CD44, CD133, CD166 and EpCAM have been proposed to represent CSC marker proteins and their expression has been shown to correlate with patient survival. Aims To evaluate a potential role of these CSC proteins in tumors of the ampulla of Vater, we investigated their expression in 175 carcinoma, 111 adenoma and 152 normal mucosa specimens arranged in a Tissue Microarray format. Materials and methods Membranous immunoreactivity for each protein marker was scored semi-quantitatively by evaluating the number of positive tumor cells over the total number of tumor cells. Median protein expression levels were used as cut-off scores to define protein marker positivity. Clinical data including survival time were obtained by retrospective analysis of medical records, tumor registries or direct contact. Results The expression of all evaluated marker proteins differed significantly between normal mucosa, adenoma and carcinoma samples. In all markers, we found a tendency towards more constant expression from normal to neoplastic tissue. EpCAM expression was significantly correlated with better patient survival. The increased expression of CD44s, CD166 and CD133 from normal mucosa samples to adenoma and carcinoma was linked to tumor progression. However, there was no statistically significant correlation with survival. Conclusion Our findings indicate, that in ampullary carcinomas, loss of expression of EpCAM may be linked to a more aggressive tumor phenotype.

Helicobacter pylori and gastric erosions. Results of a prevalence study in asymptomatic volunteers.

Background/Aims: Helicobacter pylori is considered to be the primary cause of most forms of gastritis, but its role as a causative agent in gastric erosions is unclear. The aim of this study was to estimate the prevalence of gastric erosions and H. pylori infection in asymptomatic volunteers. Methods: 175 asymptomatic subjects underwent upper gastrointestinal endoscopy. Antral biopsies were taken for bacterial cultures, histology and quick urease (CLO) test. A 13C-urea breath test was performed after endoscopy. NSAID intake, alcohol consumption and smoking habits were also recorded in each subject. Results: 33 (19%) of 175 asymptomatic volunteers had macroscopic lesions on upper gastrointestinal endoscopy, 7 were H. pylori positive, 26 were H. pylori negative. Gastric erosions occurred in 8% (14 subjects) of all volunteers. 10 subjects were H. pylori negative and 4 H. pylori positive. In 11 volunteers, gastric erosions were restricted to the prepyloric antrum. Only 1 of 14 subjects had a history of NSAID intake and 6 subjects were alcohol abstainers. Conclusion: We conclude that gastric erosions occur in a considerable amount of asymptomatic volunteers. They are predominantly localized in the prepyloric antrum and are most likely not associated with H. pylori infection, NSAID intake, smoking or alcohol consumption.

Monoclonal antibody testing for fecal calprotectin is superior to polyclonal testing of fecal calprotectin and lactoferrin to identify organic intestinal disease in patients with abdominal discomfort.

BACKGROUND AND AIMSnFecal calprotectin and lactoferrin are sensitive markers of mucosal inflammation. We compared three different assays in their ability to identify patients with organic intestinal disease.nnnMETHODSnIn a post-hoc analysis of a prospective study, we examined 405 unselected patients with abdominal complaints referred for endoscopy to the University Hospital Basel, Switzerland. Calprotectin (EK-CAL, Bühlmann Laboratories, Switzerland; PhiCal, Calpro AS, Norway) and lactoferrin (IBD-Scan, Techlab, USA) were measured using enzyme-linked immunosorbent assays. The presence of a clinically significant endoscopic finding was the primary endpoint of the study. Final diagnoses were adjudicated blinded to calprotectin values.nnnRESULTSnThe prevalence of organic intestinal disease was 35.3%. Receiver operating characteristics analysis calculated an area under the curve (AUC) for EK-CAL of 0.918, which was significantly better than for PhiCal (AUC 0.842, P<0.001) and IBD-Scan (AUC 0.830, P=0.003) to identify patients with organic intestinal disease. Overall test accuracy was 88.1% for EK-CAL, 83.7% for PhiCal, and 81.3% for IBD-Scan. Optimal cut-off value calculated for PhiCal and IBD-Scan were lower than recommended by the manufacturer.nnnCONCLUSIONSnMonoclonal testing of calprotectin is superior to both polyclonal calprotectin testing and fecal lactoferrin in identifying symptomatic patients with organic intestinal disease.

Prognostic value of cell cycle and apoptosis regulatory proteins in mismatch repair-proficient colorectal cancer: a tissue microarray-based approach.

Cell cycle and apoptosis regulatory proteins are markers of tumor progression in colorectal cancer. In a series of 1,274 mismatch repair-proficient colorectal cancers, immunohistochemical analysis of p21, p27, p53, and bcl-2 expression was performed using the tissue microarray technique. In univariate analysis, p21 expression was associated with tumor location and pN0; p27 expression with tumor location, lower tumor grade, early pT, and pN; p53 expression with tumor location; and bcl-2 with early pT and pN. Expression of p27 identified subgroups with worse prognosis in pT3 N0 and pT3 N+ patients. None of the 4 tumor markers were independent prognostic indicators of survival. The multimarker phenotypes p21/p27/p53 and p21/p27/bcl-2 were associated with survival. In mismatch repair-proficient colorectal cancer, p27 expression is associated with a better prognosis, and pT, pN, and vascular invasion are independent prognostic factors. In addition, multimarker phenotypes are useful to identify colorectal cancer subgroups with different prognoses.