Duodenal bulb biopsies in celiac disease: a multicenter study.

OBJECTIVES: Celiac disease (CD)-related lesions have been reported in duodenal bulb biopsies, sometimes the bulb mucosa being the only one affected. The aim was to verify in a significant series whether histological lesions are always present in the bulb of celiac patients, what is the prevalence of lesions when isolated to the bulb, and if similar lesions are present in nonceliac subjects. METHODS: We studied 665 children with CD (241 males, range 9 months-15 years, 8 months), at diagnosis on a gluten-containing diet, and 348 age- and sex-matched gastroenterological controls submitted to upper endoscopy for gastroenterological complaints. During endoscopy, multiple biopsies (1 bulb and 4 distal duodenum samples) were taken. Anti-endomysium antibodies were evaluated by immunofluorescence method, anti-human tissue-transglutaminase antibodies by an enzyme-linked immunosorbent assay or radioimmunoassay. Human leukocyte antigen-DRB1, -DQA1, and -DQB1 genes were typed by polymerase chain reaction sequence-specific primers repeat method. RESULTS: In all of the patients with CD, histological lesions were present in the bulb sample; in 16 of them, the lesions were present only in the bulb. Patchy villous atrophy was found in 20 children. All of the patients with CD were anti-endomysium and/or antitransglutaminase positive. The controls showed neither autoantibody positivity nor mucosal changes compatible with CD. CONCLUSIONS: This study demonstrated that CD-related histological lesions are always present in the bulb; sometimes this specific site is the only one affected. Therefore, we suggest taking 2 biopsies from the bulb and 2 from the distal duodenum for CD diagnosis.

Central effects of selective NK1 and NK3 tachykinin receptor agonists on two models of experimentally-induced colitis in rats.

Peripheral tachykinins (TKs) are believed to play a role in the pathogenesis of inflammatory bowel diseases (IBD). In this study we investigated changes induced by central administration of two natural TK receptor agonists, NK(1) (PG-SPI) and NK(3) (PG-KII), on trinitrobenzene sulphonic acid (TNBS)- and dextran sodium sulphate (DSS)-induced experimental colitis in rats. Colitis was induced by instilling a single intracolonic dose of TNBS 50 mgkg(-1) (0.5 ml in 50% ethanol) or by oral administration of 5% DSS for 7 days. Each group of rats was intracerebroventricularly injected daily with PG-SPI and PG-KII (0.5, 5, and 50 microgkg(-1)). On day 3, TNBS-treated animals were killed and the severity of gut inflammation was evaluated by measuring myeloperoxidase (MPO) activity, interleukin-1beta (IL-1beta) production and by scoring macroscopic and histologic colonic damage. DSS-treated animals were checked daily for the length of survival and for stool consistency and faecal blood. In the TNBS group, PG-SPI and PG-KII increased scores for the severity of colonic damage, stimulated the production of IL-1beta and increased granulocyte infiltration into the colon (MPO activity). In the DSS group, PG-SPI and PG-KII decreased the percentage of surviving animals, and increased the number of rats that developed loose stools and blood in the faeces and the MPO activity. These results indicate that centrally injected NK(1) and NK(3) tachykinin receptor agonists play a proinflammatory role in experimentally-induced colitis in rats.

Expression of NK-1 and NK-3 tachykinin receptors in pancreatic acinar cells after acute experimental pancreatitis in rats.

Activation of neurokinin (NK)-1 receptors but not of NK-3 stimulates amylase release from isolated pancreatic acini of the rat. Immunofluorescence studies show that NK-1 receptors are more strongly expressed than NK-3 receptors on pancreatic acinar cells under basal conditions. No studies have examined the expression of the two NK receptor populations in pancreatic acini during pancreatitis in rats. We therefore investigated the relationships between expression of these two tachykinin receptors and experimental acute pancreatitis induced by stimulating pancreatic amylase with caerulein (CK) in rats. Hyperstimulation of the pancreas by CK caused an increase in plasma amylase and pancreatic water content and resulted in morphological evidence of cytoplasmic vacuolization. Immunofluorescence analysis revealed a similar percentage of NK-1 receptor antibody immunoreactive acinar cells in rats with pancreatitis and in normal rat tissue but a larger percentage of NK-3 receptor immunoreactive cells in acute pancreatitis than in normal pancreas. Western blot analysis of NK-1 and NK-3 receptor protein levels after CK-induced pancreatitis showed no change in NK-1 receptors but a stronger increase in NK-3 receptor expression in pancreatic acini compared with normal rats thus confirming the immunofluorescence data. These new findings support previous evidence that substance P-mediated functions within the pancreas go beyond sensory signal transduction contributing to neurogenic inflammation, and they suggest that substance P plays a role in regulating pancreatic exocrine secretion via acinar NK-1 receptors. The significant increase in NK-3 receptors during pancreatic stimulation suggests that NK-3 receptors also intervene in the pathogenesis of mild acute pancreatitis in rats.

Nonspecific chronic proctitis: clinical evaluation and morphological aspects

A proctite inespecifica foi encontrada, no mais das vezes, na presenca de outras patologias do canal anal. Seus aspectos clinicos e morfologicos foram investigados para identificar a afeccao adequadamente. Os sinais clinicos sao inespecificos e constituem de secrecao mucosa, sangramento retal e tenesmo e foram frequentemente observados, inclusive apos o tratamento cirurgico de afeccoes benignas do canal anal. O estudo acabou por definir a "proctite cronica inespecifica" como doenca inflamatoria do canal anal. O uso de topicos ou de medicamentos anti-inflamatorios nesses pacientes nao modifica os aspectos endoscopicos e histopatologicos, mas controla a sintomatologia.