Ultra high magnification endoscopy: Is seeing really believing?

Endoscopy is an indispensible diagnostic and therapeutic instrument for gastrointestinal diseases. Endocytoscopy and confocal endomicroscopy are two types of ultra high magnification endoscopy techniques. Standard endoscopy allows for 50 × magnification, whereas endocytoscopy can magnify up to 1400 × and confocal endomicroscopy can magnify up to 1000 ×. These methods open the realm of real time microscopic evaluation of the GI tract, including cellular and subcellular structures. Confocal endomicroscopy has the additional advantage of being able to visualize subsurface structures. The use of high magnification endoscopy in conjunction with standard endoscopy allows for a real-time microscopic assessment of areas with macroscopic abnormalities, providing "virtual biopsies" with valuable information about cellular and subcellular changes. This can minimize the number of biopsies taken at the time of endoscopy. The use of this technology may assist in detecting pre-malignant or malignant changes at an earlier state, allowing for earlier intervention and treatment. High magnification endoscopy has shown promising results in clinical trials for Barrett's esophagus, esophageal adenocarcinoma, esophageal squamous cell cancer, gastric cancer, celiac disease, colorectal cancer, and inflammatory bowel disease. As the use of high magnification endoscopy techniques increases, the clinical applications will increase as well. Of the two systems, only confocal endomicroscopy is currently commercially available. Like all new technologies there will be an initial learning curve before operators become proficient in obtaining high quality images and discerning abnormal from normal pathology. Validated criteria for the diagnosis of the various gastrointestinal diseases will need to be developed for each method. In this review, the basic principles of both modalities are discussed, along with their clinical applicability and limitations.

Crohn's Disease Exacerbation Induced by Edwardsiella tarda Gastroenteritis.

Exacerbations of Crohn's disease are not infrequently associated with bacterial gastroenteritis. The recognition of synchronous infections in such patients is vital for the initiation of appropriate antimicrobial therapy. Furthermore, the detection of active bacterial infections may lead the clinician to delay starting biological therapy. We report here a man presenting with an exacerbation of his Crohn's disease during a trip to Thailand. Stool cultures were positive for the unusual gut pathogen Edwardsiella tarda. The patient's symptoms resolved with concurrent antibiotic and steroid therapy. This finding demonstrates the value of performing stool culture in all patients presenting with exacerbations of inflammatory bowel diseases.

Long-term use of inhaled corticosteroids and the risk of pneumonia in chronic obstructive pulmonary disease: a meta-analysis.

BACKGROUND: Recent studies have suggested a possible association between pneumonia and the use of inhaled corticosteroids. We aimed to ascertain the risk of pneumonia with long-term inhaled corticosteroid use among patients with chronic obstructive pulmonary disease (COPD). METHODS: We performed systematic searches with no date restrictions through June 30, 2008, of MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews, regulatory documents, and trial registries. We included randomized controlled trials of any inhaled corticosteroid vs a control treatment for COPD, with at least 24 weeks of follow-up and reporting of pneumonia as an adverse event. Outcomes evaluated included any pneumonia, serious pneumonia, pneumonia-related mortality, and overall mortality. RESULTS: Eighteen randomized controlled trials (n = 16 996) with 24 to 156 weeks of follow-up were included after a detailed screening of 97 articles. Inhaled corticosteroids were associated with a significantly increased risk of any pneumonia (relative risk [RR], 1.60; 95% confidence interval [CI], 1.33-1.92 [P < .001]; I(2) = 16%) and serious pneumonia (1.71; 1.46-1.99 [P < .001]; I(2) = 0%) but without a significantly increased risk of pneumonia-related mortality (1.27; 0.80-2.03 [P = .31]; I(2) = 0%) or overall mortality (0.96; 0.86-1.08 [P = .51]; I(2) = 0%). Inhaled corticosteroids were associated with a significantly increased risk of serious pneumonia when compared with placebo (RR, 1.81; 95% CI, 1.44-2.29 [P < .001]) or when the combination of inhaled corticosteroids and long-acting beta-agonists was compared with long-acting beta-agonists (1.68; 1.20-2.34 [P = .002]). CONCLUSION: Among patients with COPD, inhaled corticosteroid use for at least 24 weeks is associated with a significantly increased risk of serious pneumonia, without a significantly increased risk of death.

Clonogenic analysis reveals reserve stem cells in postnatal mammals. II. Pluripotent epiblastic-like stem cells.

Undifferentiated cells have been identified in the prenatal blastocyst, inner cell mass, and gonadal ridges of rodents and primates, including humans. After isolation these cells express molecular and immunological markers for embryonic cells, capabilities for extended self-renewal, and telomerase activity. When allowed to differentiate, embryonic stem cells express phenotypic markers for tissues of ectodermal, mesodermal, and endodermal origin. When implanted in vivo, undifferentiated noninduced embryonic stem cells formed teratomas. In this report we describe a cell clone isolated from postnatal rat skeletal muscle and derived by repetitive single-cell clonogenic analysis. In the undifferentiated state it consists of very small cells having a high ratio of nucleus to cytoplasm. The clone expresses molecular and immunological markers for embryonic stem cells. It exhibits telomerase activity, which is consistent with its extended capability for self-renewal. When induced to differentiate, it expressed phenotypic markers for tissues of ectodermal, mesodermal, and endodermal origin. The clone was designated as a postnatal pluripotent epiblastic-like stem cell (PPELSC). The undifferentiated clone was transfected with a genomic marker and assayed for alterations in stem cell characteristics. No alterations were noted. The labeled clone, when implanted into heart after injury, incorporated into myocardial tissues undergoing repair. The labeled clone was subjected to directed lineage induction in vitro, resulting in the formation of islet-like structures (ILSs) that secreted insulin in response to a glucose challenge. This study suggests that embryonic-like stem cells are retained within postnatal mammals and have the potential for use in gene therapy and tissue engineering.

Management of foreign bodies of the upper gastrointestinal tract.

The use of flexible endoscopes had made removal of foreign bodies in the upper gastrointestinal tract easier and safer. We describe our experience of 49 cases of foreign bodies of the upper gastrointestinal tract. Majority (67%) of the patients were children and only 4 patients (8%) were above 45 years of age. The most common foreign bodies encountered were coins (25), fruit stones (4) and dentures (3). In 29 patients foreign bodies were lodged in the oesophagus and in 15 cases in the stomach. Forty one patients were considered for endoscopic removal of the foreign bodies and 40 could be managed successfully. There were no procedure related complications. We conclude that endoscopic removal of the foreign bodies of the upper gastrointestinal tract is a safe and effective technique.