Role of multidetector computed tomography angiography in non-variceal upper gastrointestinal bleeding: A comprehensive review.

Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common gastroenterological emergency associated with significant morbidity and mortality. Upper gastrointestinal endoscopy is currently recommended as the gold standard modality for both diagnosis and treatment, with computed tomography traditionally playing a limited role in the diagnosis of acute NVUGIB. Following the introduction of multidetector computed tomography (MDCT), this modality is emerging as a promising tool in the diagnosis of NVUGIB. However, to date, evidence concerning the role of MDCT in the NVUGIB diagnosis is still lacking. The aim of our study was to review the current evidence concerning the role of MDCT in the diagnosis of acute NVUGIB.

Predicting mortality in non-variceal upper gastrointestinal bleeders: validation of the Italian PNED Score and Prospective Comparison with the Rockall Score.

OBJECTIVES: We sought (i) to validate a new prediction rule of mortality (Progetto Nazionale Emorragia Digestiva (PNED) score) on an independent population with non-variceal upper gastrointestinal bleeding (UGIB) and (ii) to compare the accuracy of the Italian PNED score vs. the Rockall score in predicting the risk of death. METHODS: We conducted prospective validation of analysis of consecutive patients with UGIB at 21 hospitals from 2007 to 2008. Outcome measure was 30-day mortality. All the variables used to calculate the Rockall score as well as those identified in the Italian predictive model were considered. Calibration of the model was tested using the chi2 goodness-of-fit and performance characteristics with receiver operating characteristic (ROC) analysis. The area under the ROC curve (AUC) was used to quantify the diagnostic accuracy of the two predictive models. RESULTS: Over a 16-month period, data on 1,360 patients were entered in a national database and analyzed. Peptic ulcer bleeding was recorded in 60.7% of cases. One or more comorbidities were present in 66% of patients. Endoscopic treatment was delivered in all high-risk patients followed by high-dose intravenous proton pump inhibitor in 95% of them. Sixty-six patients died (mortality 4.85%; 3.54-5.75). The PNED score showed a high discriminant capability and was significantly superior to the Rockall score in predicting the risk of death (AUC 0.81 (0.72-0.90) vs. 0.66 (0.60-0.72), P<0.000). Positive likelihood ratio for mortality in patients with a PNED risk score >8 was 16.05. CONCLUSIONS: The Italian 10-point score for the prediction of death was successfully validated in this independent population of patients with non-variceal gastrointestinal bleeding. The PNED score is accurate and superior to the Rockall score. Further external validation at the international level is needed.

Characterization of intestinal bacteria tightly bound to the human ileal epithelium.

In order to perform selective isolation of bacteria tightly bound to the human gut, ileal biopsies of healthy volunteers were treated to wash out the mucus layer and loosely bound bacterial cells. Rod-shaped anaerobic bacteria that had remained attached to the epithelial cells were isolated and identified at the species level. One isolate was identified as belonging to the Bifidobacterium breve species, while all the others were lactobacilli of only two species, Lactobacillus mucosae and Lactobacillus gasseri. Members of these species were found previously in intestinal samples, but their predominance among bacteria strictly associated with the epithelium was not suspected before and suggests that these species may represent a specific subpopulation of tissue-bound bacteria. Physiological analysis indicated that all isolates were able to produce antimicrobials, grow and form biofilm in simulated intestinal fluid after exposure to gastric conditions. Some isolates were able to degrade mucin while none showed cytotoxicity in vitro on HT29 cells. The tight association of the strains isolated with ileal epithelial cells is presumably indicative of a direct interaction with the host cells. For this reason and for the absence of cytotoxicity in vitro, those isolates can be proposed as potential probiotic strains for human use.

Small intestinal contrast ultrasonography-based scoring system: a promising approach for the diagnosis and follow-up of celiac disease.

BACKGROUND: Small intestinal ultrasonography with anechoic contrast agents (SICUS) has been shown to have a diagnostic accuracy on small bowel morphology similar to X-ray barium follow-through. Although extremely investigated by transabdominal ultrasonography, celiac disease, a common disorder of the small bowel, has been never studied by SICUS. AIM: To asses SICUS characteristics of celiac disease patients. PATIENTS AND METHODS: SICUS was performed using PEG 4000 as contrast agent. Twenty-three patients with celiac disease at the first diagnosis were enrolled and 30 healthy volunteers, matched for sex and age, were selected as control group. Celiac disease diagnosis was based on anti-gluten, anti-endomysium, and anti-transglutaminase positivity as well as jejunal histology. The following seven echographic parameters were considered: liquid endoluminal content before contrast, loop diameter, Kerckring's folds, peristaltic waves, ileal jejunalization, mesenteric lymphoadenomegaly, and Doppler resistance index (RI) of mesenteric superior artery. Statistical analysis was performed by Student's t test for unpaired data; one-way analysis of variance was used to correlate echographic and histologic pictures. RESULTS: Loop diameter, Kerckring's fold number, peristaltic waves, and Doppler RI appeared to be significantly different between celiac disease patients and controls. Additionally, liquid content, ileal jejunalization, and mesenteric lymphoadenomegaly were present only in the celiacs (52.1%, 47.7%, and 95.6%, respectively), but not in controls. Only Doppler RI values significantly correlated with the histologic degree of damage. CONCLUSIONS: SICUS could be a reliable and noninvasive technique to confirm a diagnosis of celiac disease performed using conventional investigations. The possibility of investigating the whole small bowel and the safety of repeating examinations could be useful in the follow-up of celiac patients.