Complications included 1 patient requiring a transfusion and another pa- tient leaking around the tube for 4 days. Conclusion: PEG tubes are safe and effective and allows these patients to continue therapy or be discharged to hospice without the discomfort of a nasogastric tube. 306 Anti-tissue transglutaminase antibodies (TTGAb): Relevance of quantitative assay Segato S. Bisso G., Ferraris L., Gianfrate L., Bonecco S., Curzio M. Unita’ Operativa di Gastroenterologia—Ospedale di Varese—Italy. Antibodies anti-tissue TransGlutaminase have been recently proposed as an accurate test for the diagnosis and follow-up of Celiac Disease (CD). Aim of this study was to verify the reliability of the test in a clinical setting. Materials: 30 untreated celiac patients (M:F ratio = 4:26; age range 13– 65 yrs; mean age 36.5; group A) were studied along with 46 celiac patients on gluten-free diet for at least 2 years (M:F = 8 –38; age range 17– 68; mean age 35.3; group B) and 38 control patients (M:F = 20 –18; age range 25– 89; mean age 62.4; group C). None had IgA deficiency. We examined serum samples for Ab anti TTG with commercial ELISA test (Genesis Diagnostics). Optical density was considered positive if 10 U/ml as suggested by the producer. For all patients we obtained endoscopic duo- denal biopsies for morphologic evaluation of the mucosa. Results: In group A 28 patients were positive for Ab anti TTG and 2 were negative, in all cases duodenal biopsy showed various degrees of villous atrophy. In group B of 18 positive patients, 10 had normal histology and 8 some degree of alteration. All these 8 patients admitted poor compliance with gluten free diet and had mean optical densities 20 U/ml. In group C 34 patients had ELISA mean optical density 10 U/ml and 4  10 U/ml all with normal histology, none had values 20 U/ml. When we compared the results of ELISA tests with histology using a cut-off value of 10 U/ml the sensibility was 95% and the specificity 86% with a positive predictive value of 76% and a negative predictive value of 97%. Moving the cut off to 20 u/ml sensibility was 76%, specificity 100%, positive predictive value 100% and negative predictive value 88%. Conclusions: Ab anti TTG have high sensibility. The specificity of the test is high only for high concentrations. Values between 10 and 20 U/ml are not closely correlated to histological lesions. 307 Expression of antimicrobial peptides in the duodenal mucosa Shen B, MD, Ormsby A, MD, Dumot J, DO, Ghosh D, PhD, Lashner B, MD, FACG, Achkar, J-P, MD, Brzeinski A, MD, FACG, Bevins C, MD, FACG. The Cleveland Clinic Foundation, Cleveland, OH. Gastric acid is held as largely responsible for antimicrobial defense of the upper gut. However, with the wide use of proton pump inhibitors there is little evidence for increased risk of microbial infection, suggesting other defense mechanisms are present in the upper gut. Aim: To identify possible expression of antimicrobial peptides in the duodenal mucosa. Methods: Surgically resected or endoscopically biopsied specimens from the proximal duodenum (N = 10) and terminal ileum (TI) (N = 10) were studied by human defensin-5 (HD5), lysozyme, and secretory phos- phalipase A 2 (sPLA 2 ) immunohistochemistry. Selected specimens were studied by Northern blot analysis for mRNA. Results: Lysozyme was present in both duodenal crypts and Brunner’s glands. HD5 and sPLA 2 were detected at the base of duodenal crypts in majority of cases (Table). The synthesis of the antimicrobial peptides in the duodenum was confirmed by demonstration of mRNAs by Northern blot analysis. Paneth cells of the distal small intestine which also express HD5, lysozyme, and sPLA 2 appeared morphologically distinct by H&E staining compared to the crypt cells in the duodenum (Table). Conclusion: HD5, lysozyme, and sPLA are produced in crypts of the duodenum. Lysozyme is also produced in the Brunner’s glands. These factors contribute to host defense of upper gut, similar to their proposed role in the TI. Proximal Duodenum Terminal Ileum Crypt Gland Crypt Number of Cases 10 10 10 HD5 positive staining 10 0 10 Lysozyme positive staining 10 10 10 SPLA 2 positive staining 7 0 10 Cytoplasmic secretory granules absent absent present 308 Human defensin-5 immunohistochemistry and Paneth cell morphology helps to differentiate Crohn’s colitis from active ulcerative colitis Shen B, MD, Lashner B, MD, FACG, Achkar J-P, MD, Brzezinski A, MD, FACG, Ghosh D, PhD, Seidner D, MD, Porter, E, MD, Ganz T, MD, Fazio V, MD, Bevins C, MD, FACG. The Cleveland Clinic Foundation, Cleveland, OH and UCLA, Los Angeles, CA. Background: Distinguishing Crohn’s disease (CD) from ulcerative colitis (UC) is sometimes difficult. Approximately 15% of cases defy clear cat- egorization. Current biologic markers lack adequate sensitivity and speci- ficity. Human defensin-5 (HD5) is an antimicrobial peptide, produced by Paneth cells in the crypts of the distal ileum. However, HD5 expression in the terminal ileum (TI) of CD and UC has not been previously studied. Aim: To assess whether HD5 immunoreactivity in conjunction with Paneth cell histology may be useful to differentiate CD from UC. Methods: Consecutive patients with active CD colitis (N = 6), active UC (N = 17), inactive UC (N = 6), and normal controls (N = 16) were enrolled in the study. Disease activity of CD and UC was classified based on endoscopic and histologic findings. Endoscopically biopsied (N = 28) or surgically resected (N = 17) specimens of the TI were studied by HD5 immunohistochemistry and Paneth cell histochemistry (phloxine-tartrazine stain to enhance visualization of the cytoplasmic eosinophilic granules normally present in Paneth cells). Results: HD5 immunoreactivity was detected in crypt cells of the TI in all specimens. The HD5-expressing cells in all normals, all CD colitis and all inactive UC had typical eosinophilic cytoplasmic granules. In contrast, these granules were absent in HD5-expressing cells in 82.4% cases of active UC (P  0.05). By combining HD5 immunoreactivity and Paneth cell histology, we were able to differentiate active UC from the other groups with sensitivity of 82.4% and specificity of 100%. Conclusion: The presence of cytoplasmic secretory granules in HD5- expressing cells in the TI was characteristic of normal, CD colitis, and inactive UC, whereas the absence of these granules was characteristic of active UC. The feature may be useful in distinguishing active CD colitis from active UC. 309 Upregulation of human defensin-5 in acute pouchitis suggests an infectious etiology Shen B, MD, Achkar J-P, MD, Lashner B, MD, FACG, Brzezinski A, MD, FACG, Ghosh D, PhD, Remzi F, MD, Goldblum J, MD, Fazio V, MD, Seidner D, MD, Ganz T, MD, Bevins C, MD, FACG. The Cleveland Clinic Foundation, OH, and UCLA, CA. Pouchitis is the most common long term complication of ileal pouch anal anastomosis (IPAA) after total proctocolectomy (TPC), but its pathogen- esis is not clear. Most cases of acute pouchitis respond to antibiotic therapy, suggesting an infectious etiology. 2501 AJG – September, 2000 Abstracts