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Background and Aims: Oxidative stress is presumed to play an important role in Crohn's disease (CD) pathogenesis. Nevertheless, the evaluation of the intestinal antioxidant capacity through the analysis of glutathione peroxidase activity in CD remains to be determined., Methods: 20 CD outpatients and 16 volunteers going through colonic cancer screening were enrolled. Colonoscopy with biopsies was performed in all individuals. Samples from inflamed and non-inflamed mucosa were taken when there was CD endoscopic activity. Spectrophotometric assays were performed to measure tissue glutathione peroxidase (GPx) activity, and total (GSHT) and oxidized (GSSG) glutathione in all samples. Demographics and clinical characteristics were collected from clinical charts., Results: Inflamed CD mucosa presented reduced GPx activity compared to non-inflamed CD mucosa (42.94mU/mg protein vs 79.62mU/mg protein, P<0.05) and control mucosa (42.94mU/mg protein vs 95.08mU/mg protein, P<0.001). GSHT concentration was reduced in inflamed mucosa when compared to non-inflamed CD mucosa (0.78μmol/g vs 1.98μmol/g, P<0.01) and the control group (0.78μmol/g vs 2.11μmol/g, P<0.001). A significant correlation was detected between GPx activity and GSSG (r=-0.599), disease duration (r=0.546), and thiopurine treatment (r=-0.480) in non-inflamed CD mucosa., Conclusion: Our findings suggest that reduced GPx activity is present in inflamed CD mucosa. In addition, endoscopic activity, disease duration and thiopurine therapy could be associated with mucosal decreased antioxidant activity., (Copyright © 2013 European Crohn's and Colitis Organisation. Published by Elsevier B.V. All rights reserved.)

Pseudomelanosis duodeni (PD) is a rare dark speckled appearance of the duodenum associated with gastrointestinal bleeding, hypertension, chronic heart failure, chronic renal failure and consumption of different drugs. We report four cases of PD associated with chronic renal failure admitted to the gastroenterology outpatient unit due to epigastric pain, nausea, melena and progressive reduction of hemoglobin index. Gastroduodenal endoscopy revealed erosions in the esophagus and stomach, with no active bleeding at the moment. In addition, the duodenal mucosa presented marked signs of melanosis; later confirmed by histopathological study. Even though PD is usually regarded as a benign condition, its pathogenesis and clinical significance is yet to be defined.

Forty-five patients with systemic lupus erythematosus (SLE) underwent a cross-sectional study to evaluate intestinal secretory immunity. Peroral jejunal biopsy with histologic and immunohistochemical assessment of the mucosa were carried out in the patients and in 12 healthy volunteers. It was observed that an altered pattern of immunoglobulin-bearing plasma cells distributed in the lamina propria and complementary components were invariably present, mainly in the patients with active disease. The basement membrane of the intestinal crypt epithelium exhibited immunoglobulin and complementary deposits, similar to the lupus band test. None of the immunologic findings correlated with the medical treatment and with the peripheral blood analysis. The local changes in humoral immunity in patients with SLE did not correlate with gastrointestinal symptoms and may reflect the systemic effects of the disease.

Objective: The objective of this study was to examine mononuclear cell subpopulations and evidence of cellular activation in unaffected jejunal mucosa in Crohn's disease., Design: A cross-sectional study was performed in patients with Crohn's disease from the ambulatory unity of the University Hospital, UFRJ., Methods: Mucosal samples from 20 patients with Crohn's colitis or ileitis were obtained by peroral jejunal biopsy. Patients with jejunal involvement or pregnant women were excluded from the study. Specimens were analysed histologically and by indirect immunoperoxidase method using anti-monoclonal antibodies to CD2, CD4, CD8, CD25, CD45RO, RFDR1, RFD1 and RFD7 by two 'blind' observers. Seven patients with non-inflammatory bowel disorders and two healthy volunteers were studied as controls., Results: Lamina propria CD2-positive (CD2+) cells were reduced in Crohn's disease (P < 0.004) whether clinically active (P < 0.02) or clinically inactive (P < 0.008). CD4+ and CD8+ cells were also reduced in Crohn's disease (P < 0.003), whereas the CD4:CD8 ratio did not differ from that in controls. CD25+, CD45RO+ and HLA-DR+ cells were not significantly increased in patients with Crohn's disease. RFD7+ cells were decreased in Crohn's disease (P < 0.02), whereas RFD1+ cells were not significantly different from the control group., Conclusion: No evidence of cellular activation was found in the unaffected mucosa of Crohn's disease. The reduction in T-cell and macrophage-like cell numbers may result from cell migration to inflamed areas. It is also possible that this finding represents a primary defect which may have a role in the pathogenesis of Crohn's disease.

1. The purpose of the present study was to evaluate the intestinal secretory immunity of HIV-infected patients. Jejunal biopsies were obtained with a Watson capsule from 52 HIV-infected patients and compared to a control group consisting of 12 healthy subjects, matched for age and sex. IgA- and IgM-containing plasma cells were studied by immunofluorescence by two independent observers who had no knowledge of the history of the slides. 2. The IgA and IgM plasma cell density was significantly decreased in HIV-infected patients when compared to the controls (31/52 for IgA and 42/52 for IgM in the HIV group and normal density in all controls). The depletion of intestinal plasma cells was an early feature of HIV disease and did not correlate with diarrhea, enteropathogens or mucosal atrophy. Although IgA plasma cell depletion has been described in HIV infection, this is the first report of IgM cell density reduction. 3. A peripheral fluorescence pattern was observed in the intestinal cells of HIV-infected patients, contrasting with the normal cytoplasmic fluorescence pattern seen in controls. The cells presenting a rim of peripheral fluorescence in HIV disease might correspond to immature B lymphocytes. 4. The intestinal plasma cell depletion may result in hampered mucosal defense in HIV disease, and is likely to be a direct consequence of T lymphocyte function impairment. 5. The data indicate that the intestinal secretory immune system is altered in AIDS and also in the early stages of HIV disease.

Forty-nine HIV-infected patients were submitted to peroral jejunal biopsy in order to evaluate the presence of microorganisms and the histomorphometric aspects of the enteric mucosa with subsequent correlation of these findings to the appropriate clinical stage of the disease. Thirty-seven patients fulfilled the CDC criteria for AIDS, of whom 23 presented with diarrhea. Of the 12 patients who had not yet been given an AIDS diagnosis. 3 had persistent generalized lymphadenopathy and 9 were asymptomatic carriers. Flat mucosa was observed in two patients (8.7%) with diarrhea and coccidea. Subtotal villous atrophy and severe lamina propria (LP) mononuclear infiltrate (13%) were found only in patients with diarrhea. Moderate to severe histologic changes were more frequently observed in this group, not always related to the presence of microorganisms. Crypt hyperregeneration was a constant finding. Intraepithelial lymphocyte (IEL) count was decreased in patients with diarrhea. Specific infectious agents were unexpectedly rare for the tropical developing country population studied. The organism most commonly associated with diarrhea was Cryptosporidium sp. (21.7%). The etiology of diarrhea in a significant number of patients remains unclear.