Changes in gastrointestinal permeability in celiac disease

Increased gastrointestinal permeability was found in celiac disease already 20 years ago. Originally a genetical defect was supposed leading to elevated permeability and later to celiac disease. However, patients under long-term gluten-free diet normalized their permeability tests. On the other side, unaffected relatives of patients with celiac disease showed high permeability but not different from patients with irritable bowel syndrome and with a tendency for normalization during follow-up. In active symptomatic celiac disease, permeability is elevated in the gastroduodenum - measured by sucrose test - as well as in the small intestine - measured by lactulose/mannitol ratio. The sensitivity in active celiac disease is high (near 100%), the specificity is low due to high permeability in many intestinal diseases as in acute infectious gastroenteritis, Crohn's disease, nonsteroidal anti-inflammatory drug treatment, etc. In contrast, lactulose/mannitol test permeability is much less sensitive in silent celiac disease without diarrhea (74%). The real importance of permeability disease is established by its use for follow-up of celiac patients under gluten-free diet whereas it is correlated to the degree of mucosal atrophy. In vitro tests also show increased lactulose mucosal to serosal flux in celiac disease, but not correlated to oral permeability test. In conclusion, lactulose/mannitol test is the only noninvasive functional test in celiac disease which has essential importance in active celiac disease and in follow-up under diet.

Broadband ultrasound attenuation of the calcaneus. A tool for assessing bone status in patients with chronic renal failure

PURPOSE

To evaluate broadband ultrasound attenuation (BUA) for the assessment of bone status and to correlate this to dual-energy X-ray absorptiometry (DXA) in haemodialysis patients.

MATERIAL AND METHODS

In 60 patients, BUA (dB/MHz) was determined for the calcaneus. The results were expressed as Z-scores and T-scores, i.e. units of standard deviations respectively from age- and sex-matched normal values and from sex-matched normal mean values in healthy young adults. Ultrasound data were correlated to relevant clinical, biochemical and DXA data (g/cm2), which were examined at the femoral neck and at the lumbar spine in 50 patients.

RESULTS

The BUA Z-score was < -1 in 53% of the patients and < -2 in 22%. The BUA T-score was < -1 in 88% and < -2 in 62%. Moderate correlation was found for calcaneal BUA to DXA in men (r = 0.47-0.48, p < 0.01) and to DXA of the lumbar spine in women (r = 0.51, p < 0.05). The best correlation was observed for BUA to DXA of the femoral neck in women (r = 0.61, p < 0.01).

CONCLUSION

Calcaneal BUA is an additional tool for the surveillance of bone density in haemodialysed patients.

In vitro model of the pathogenesis of celiac disease

The in vitro challenge of duodenal mucosa with gliadin is a useful model to reproduce the immunological features of celiac disease (CD) and allows the study of early pathogenetic events in this disease. With this model it was shown that antigens such as ICAM-1 and HLA-DR are upregulated as early as 1-2 h after gliadin challenge in patients with CD. After 24 h the lamina propria contained CD4+ T cells expressing the IL-2 receptor alpha-chain, which is a sign of activation. Intraepithelial lymphocytes increased in number and showed proliferative activity. After in vitro stimulation with gliadin, endomysial antibodies were found in the supernatant of the cultured mucosa from patients with CD following a gluten-free diet. This supported the notion that endomysial antibodies are at least in part produced locally. The model was also successfully used to identify toxic constituents of gliadin. Presently, organ culture is not commonly used for diagnostic purposes.

Influence of topically and systemically active steroids on circulating leukocytes in Crohn's disease

OBJECTIVE

Budesonide, although only topically active, is effective in the treatment of Crohn's disease. This study was performed to compare the clinical efficacies of budesonide and prednisolone in relation to the activation status of circulating leukocytes.

METHODS

Twenty-four patients with active Crohn's disease were randomized to treatment with either budesonide or 6-methylprednisolone. Clinical response was monitored by the Crohn's disease activity index, C-reactive protein, and orosomucoid. Expression of CD25 and CD71 on T cells and CD64 on neutrophils was determined by flow cytometry. The release of TNF-alpha and IL-1beta by peripheral blood mononuclear cells was measured by ELISA.

RESULTS

After 2 wk of treatment a clinical response was observed in both groups, but it was more accentuated in patients treated with prednisolone. At baseline an upregulation of CD71 and CD64, but not CD25, was found in active patients. Prednisolone significantly decreased the expression of CD64 and the release of TNF-alpha and IL-1beta, but did not alter the expression of CD25 and CD71. Budesonide treatment failed to exert any effect on circulating leukocytes.

CONCLUSIONS

The inability of budesonide to downregulate activated circulating leukocytes may contribute to the somewhat lower clinical efficacy of this topical steroid in the treatment of active Crohn's disease.

[Cyclosporin A therapy in steroid-refractory patients with chronic inflammatory bowel diseases]

About eighty percent of patients with severe ulcerative colitis refractory to steroids are responsive to intravenous cyclosporine therapy within a few days. However, no controlled data are available on intravenous cyclosporine therapy in steroid refractory Crohn's disease. In this study 7 patients with severe ulcerative colitis and 4 patients with active Crohn's disease unresponsive to prednisone were treated with high dose intravenous cyclosporine. A response was estimated by a decrease of Crohn's disease activity index (Best) and colitis activity index (Rachmilewitz). Six of 7 patients with ulcerative colitis showed a significant decrease in colitis activity index (index before therapy: 15 +/- 2; one week later: 7 +/- 1; p < 0.001). In these patients prednisone could be tapered to a dose less than 20 mg/day within 6 months during oral cyclosporine and concomitant azathioprine therapy. Cyclosporine medication was withdrawn within a few weeks and the clinical response could be preserved for another 6 months. In 3 of 4 patients with Crohn's disease intravenous cyclosporine led to a temporary improvement of the Crohn's disease activity index (before treatment: 343 +/- 43, after one week: 194 +/- 20; p < 0.05). Nevertheless, all of these patients had an early relapse under oral cyclosporine therapy. Our data confirm the efficacy of intravenous cyclosporine as a rapid acting drug for severe ulcerative colitis. Maintenance therapy with azathioprine preserved the clinical response for one year. In patients with steroid refractory Crohn's disease intravenous cyclosporine showed only a short term effect.

Chromatographic resolution of ciprofibrate and interaction of the racemate and both enantiomers with rat liver microsomes in vitro

The enantiomers of ciprofibrate may be achieved by enantioselective HPLC separation of its methylesters using a OD - Daicel column. Ciprofibrates (racemate and both enantiomers) bind to oxidized cytochrome P-450 in rat liver microsomes according type II like aniline or most probably as inversed type I, but less pronounced and with a general shift to the left. Ethylmorphine N-demethylation, ethoxycoumarin and ethoxyresorufin O-deethylation are all inhibited by the ciprofibrates, most effectively ethoxyresorufin O-deethylation by S(-)-ciprofibrate even in microM concentrations. Microsomal luminol and lucigenin amplified chemiluminescence indicating the formation of reactive oxygen species, microsomal hydrogen peroxide formation and NADPH/Fe stimulated lipid peroxidation were inhibited in a concentration dependent manner in concentration ranges between mM and microM. This might be due to distinct scavenger activities of all 3 compounds: the zymosan stimulated chemiluminescence of whole blood was completely inhibited in mM concentrations and influenced significantly down to concentrations of 10 microM, whereas burst and phagocytosis tests with human polynuclear leucocytes were not influenced.

Beta interferon is produced by Chlamydia trachomatis-infected fibroblast-like synoviocytes and inhibits gamma interferon-induced HLA-DR expression

Infection of fibroblast-like synovial cells with Chlamydia trachomatis (serotype D strain IC Cal 8) in culture induced the secretion of beta interferon (IFN-beta). Chlamydial infection inhibited IFN-gamma-induced expression of HLA-DR antigen in the cells. Addition of IFN-beta antibody directly to infected cultures mitigated HLA-DR inhibition, suggesting involvement of produced IFN-beta.

Microsatellite instability and loss of heterozygosity in gastric carcinoma in comparison to family history

We compared 29 gastric carcinomas from patients with a variably strong family history for gastric cancer (group 1) with 36 gastric carcinomas from patients without a family history of this disease (group 2) for microsatellite instability (MSI) and loss of heterozygosity (LOH) with 12 microsatellite markers. Both study groups had similar proportions of histological types and tumor locations. Widespread MSI (alterations at > or = 6 loci) was seen in 5 of 29 (17%) of the tumors belonging to group 1 and in 4 of 36 (11%) group 2 tumors. MSI at a low level (alterations at 1 to 3 loci) was observed in 12 of 29 (41%) of tumors in group 1 and in 10 of 36 (28%) of tumors in group 2, differences that were not statistically significant. A significant difference with respect to low level MSI was observed between the two groups when considering the overall mutation rate of microsatellites. Seventeen of 281 (6%) analyzed microsatellite loci showed alterations in group 1 and 11 of 381 (2.9%) in group 2 (P = 0.046). Comparison of both types of MSI to the clinicopathological parameters in both groups revealed a significant association of low level MSI with advanced tumor stages (P = 0.046) in the group 2, whereas no such association was observed in group 1. In respect to LOH, a significant difference between the two groups was observed at chromosome 17p12, as 13 of 22 (59%) informative cases of group 1 showed LOH in comparison with 7 of 26 (27%) (P = 0.024) in group 2. No correlation of LOH at chromosome 17p12 to the pathological or clinical data was observed either in the two groups or in the study as a whole. Our data show that gastric carcinomas of patients with a positive family history of gastric cancer in group 1 are characterized by a higher mutation rate in respect to low level MSI, particularly at dinucleotide repeats, and by a higher frequency of LOH at chromosome 17p12, indicating that different genetic pathways are involved in the pathogenesis of gastric carcinomas arising in patients with and without a familial background of this disease.

Conflicting results of ileoscopy and small bowel double-contrast barium examination in patients with Crohn's disease

BACKGROUND AND STUDY AIMS

Ileoscopy has become a routine procedure for the diagnosis of Crohn's disease of the terminal ileum. The aim of this study was to compare the diagnostic accuracy of small bowel barium examination with that of ileoscopy.

PATIENTS AND METHODS

In a retrospective study the two methods were compared in 55 patients with Crohn's disease. First, routine radiology reports and second, reevaluation of the small bowel barium study by gastrointestinal radiologists with scoring of examination quality were compared with the results of ileoscopy.

RESULTS

Using routine radiology reports, 66% sensitivity and 82% specificity were reached for inflammatory changes of the terminal ileum by small bowel barium study. Sensitivity and specificity increased to 68% and 91% with double reading by experienced radiologists. Disagreement between endoscopic and radiologic results changed from 31% to 27% and were mainly because of false-negative barium studies. Sensitivity and specificity of barium studies were influenced by the quality of the examination with a sensitivity of 91% and specificity of 100% when the quality was good.

CONCLUSIONS

In patients in whom the terminal ileum is successfully intubated, ileoscopy is superior to barium examination in the evaluation of Crohn's disease of the terminal ileum. Results of the barium study were strongly influenced by the quality of the examination.

High proportion of granzyme B-positive (activated) intraepithelial and lamina propria lymphocytes in lymphocytic gastritis

Intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LpLs) have not been well studied in gastric mucosa, particularly in lymphocytic gastritis. Therefore, they were immunohistologically characterized with antibodies recognizing CD3, CD8, CD57, T cell-restricted intracellular antigen (TIA-1), and granzyme B (GrB). The TIA-1 labels cytotoxic granules of resting and activated T-cells, whereas GrB decorates activated cytotoxic T cells. Thirty patients with celiac disease, including 20 taking gluten and 10 on a gluten-free diet, 15 patients with nonceliac disease-associated lymphocytic gastritis, and 20 controls were studied. Stained cells were counted and results were given as IELs/100 epithelial cells or percentage of lamina propria cells. Sixty percent to 90% of CD3+ IELs and up to 12% of lamina propria cells contained TIA-1-positive cytotoxic granules. The number of GrB+ IELs and LpLs was increased in Helicobacter pylori-positive controls (p < 0.03 vs. H pylori-negative controls) and celiac disease patients taking gluten (p < 0.05 vs. controls). The highest number of GrB+ IELs and LpLs was found in nonceliac disease-associated lymphocytic gastritis (p < 0.009 vs. controls, p < 0.05 vs. celiac disease). This study shows that a high proportion of gastric IELs and LpLs is potentially cytotoxic in nature. Through stimuli not yet identified, a proportion of them becomes activated after H pylori infestation and in lymphocytic gastritis.

[Carbohydrate-deficient transferrin (CDT) as preoperative alcohol marker in surgical risk patients]

In a prospective study the preoperative risk of alcohol addiction was evaluated in 46 patients with squamous cell carcinoma of the esophagus. In all patients the alcohol marker carbohydrate-deficient transferrin (CDT) was measured prior to esophagectomy and correlated with the incidence of postoperative withdrawal symptoms (yes/no) and the postoperative course (good/moderate/poor/fatal). Withdrawal symptoms were more frequently observed in cases of elevated CDT values (median of CDT with withdrawal 17.0 U/l vs without withdrawal 10.7 U/l; P = 0.0006). CDT values were significantly increased in case of a complicated postoperative course (median of CDT for moderate/poor/fatal postoperative course 14.0 U/l vs good course 10.8 U/l; P = 0.02). The CDT value correlated (P = 0.04) with the patient's history of preoperative alcohol consumption (normal/increased/high). In a multivariate logistic regression analysis CDT and preoperative alcohol consumption were independent parameters to predict significantly the postoperative course and withdrawal. The sensitivity was 71.4% and the specificity 84.4% selecting the parameter "postoperative withdrawal" and a CDT cut-off point of < 15.3 U/l. CDT can effectively identify patients with high alcohol consumption prior to esophagectomy.

Gastroduodenal permeability in Crohn's disease

BACKGROUND

Gastric permeability was prospectively investigated by determination of sucrose excretion in 100 patients with Crohn's disease. Results were compared with histological findings and the lactulose-mannitol ratio as a measure of intestinal permeability.

METHODS

All subjects underwent oesophagogastroduodenoscopy with biopsies of all investigated parts. Thirty-two Helicobacter pylori-positive patients were excluded from further analyses.

RESULTS

Gastroduodenal permeability was significantly higher in patients with Crohn's disease than in control subjects (P < 0.00001). Sucrose excretion alone did not predict microscopic inflammation of the upper gastrointestinal tract. Increased gastroduodenal permeability with a concomitant rise in intestinal permeability predicted histological upper gastrointestinal involvement of Crohn's disease with a likelihood of 86%. The negative predictive value was 43%.

CONCLUSION

In parallel with findings in the small intestine, gastroduodenal permeability is increased in a high proportion of patients with Crohn's disease. In patients with an increased lactulose-mannitol ratio, elevated sucrose excretion is highly predictive of histological gastroduodenal involvement.

Sucrose permeability as a marker for NSAID-induced gastroduodenal injury

OBJECTIVE

To evaluate sucrose permeability as a non-invasive test for the monitoring of upper gastrointestinal mucosal damage (uGMD) in patients treated with NSAIDs.

METHODS

40 patients with non-inflammatory joint pain were enrolled in a prospective study. Before and after 14 days of ibuprofen treatment (3 x 400 mg/day), the rates of urinary sucrose excretion after an oral sucrose load were assessed. Individuals with increased sucrose permeability underwent endoscopy.

RESULTS

8 patients (20%) showed abnormal sucrose permeability before taking any NSAID. In 5/20 patients (25%) who completed 2 weeks of ibuprofen medication, sucrose excretion increased above the normal level. Endoscopic examination and biopsy revealed mild uGMD, but no ulceration in 8/11 (72%) patients with increased permeability to this marker.

CONCLUSION

Sucrose permeability testing is a sensitive procedure for research protocols on NSAID-induced gastropathy. Since this test also seems to detect slight and clinically insignificant mucosal damage, however, its use in clinical decision-making regarding gastroprotective medication is limited.

Increased gastric and intestinal permeability in patients with Crohn's disease

OBJECTIVES

Patients with Crohn's disease exhibit marked changes in intestinal permeability that can be assessed by lactulose and mannitol. Sucrose is a novel marker for gastric permeability. We combined these three sugars to investigate whether patients with Crohn's disease demonstrate changes in gastric permeability and if so, whether these changes are matched with altered intestinal permeability.

METHODS

Fifty patients with Crohn's disease and 30 healthy subjects each drank a solution containing 20 g of sucrose, 10 g of lactulose, and 5 g of mannitol. Patients' and subjects' 5-h sugar urinary excretion levels were determined by high performance liquid chromatography and an enzymatic method (sucrose). Furthermore, patients with Crohn's disease underwent endoscopy of the upper GI tract and were grouped according to endoscopic and histological findings.

RESULTS

Patients with Crohn's disease showed higher gastric and intestinal permeability compared with healthy control subjects. Gastric permeability was correlated with intestinal permeability. Patients with granuloma had more pronounced changes in both gastric and intestinal permeability than patients with various endoscopic and histological lesions. Patients with normal mucosa had normal permeability.

CONCLUSIONS

Alterations in gastric mucosa caused by Crohn's disease are reflected by changes in gastric permeability and can be used to noninvasively screen for Crohn's disease involvement of the upper GI tract.

No evidence of activated blood coagulation in Crohn's disease

BACKGROUND

Thromboembolism seems to be a significant and serious complication in Crohn's disease (CD), and multifocal microvascular infarction of the intestinal mucosa may be an important effector mechanism in the pathogenesis of CD. Therefore, it has been hypothesized that an increased activation of the blood coagulation system may favour thromboembolic complications.

OBJECTIVES

To assess the activity of blood coagulation as a potential index of thromboembolic risk in CD using thrombin-antithrombin III complex (TAT).

DESIGN

Prospective evaluation of TAT.

SETTING

Out-patients at the gastroenterological department of a university hospital.

PATIENTS

Eighty patients with CD, 47 with inactive (Crohn's disease activity index (CDAI) < 150) and 33 with active disease, and 80 healthy controls were investigated in this study.

METHODS

TAT and fibrinogen were used as parameters of blood coagulation. C-reactive protein and orosomucoid were used as serum inflammatory parameters.

RESULTS

Fibrinogen was significantly higher in patients with active CD (median 535 mg/dl; interquartile range 402-620 mg/dl) than in patients with inactive CD (357 mg/dl; 300-467 mg/dl) or controls (268 mg/dl; 231-299 mg/dl). Fibrinogen correlated with CDAI, C-reactive protein and orosomucoid. TAT did not show any difference between patients with active CD (3.2 ng/ml; 2.5-4.6 ng/ml), inactive CD (3.0 ng/ml; 2.4-3.9 ng/ml) and controls (3.1 ng/ml; 2.3-3.6 ng/ml). Correspondingly, TAT correlated neither with serum inflammatory parameters and CDAI nor with fibrinogen.

CONCLUSION

We could not find evidence of activation of the blood coagulation system as determined by TAT plasma levels in CD, not even in patients with active disease. TAT is not, therefore, a potential index of thromboembolic risk in CD and of microvascular infarction as an effector mechanism in the pathogenesis of CD.

25-hydroxyvitamin D absorption in patients with Crohn's disease and with pancreatic insufficiency

Vitamin D malabsorption could be one possible reason for the high prevalence of vitamin D deficiency and osteopenia in patients with Crohn's disease (CD) and pancreatic insufficiency (PI). Hence, we performed a modified 25-hydroxyvitamin D (25-OHD) absorption test Stamp in 15 healthy controls, 31 patients with CD and 10 patients with PI. Serum 25-OHD levels were measured before, and 2, 4, 8, and 24 hours after oral administration of 5 micrograms 25-OHD/kg body weight. Basal 25-OHD levels were below the normal range of 12-36 ng/ml in 68% of patients with CD (median: 10; interquartile range: 4-12 ng/ml) and 70% of patients with PI (median: 3; interquartile range: 2-14 ng/ml). Peak levels were reached at 4 or 8 hours after ingestion of 25-OHD. Three patients with CD (10%) and 5 patients with PI (50%) showed decreased 25-OHD absorption. 25-OHD levels normalized in all but two patients with PI after 24 hours. Pattern of involvement or previous resections did not show a significant influence on 25-OHD absorption. Vitamin D malabsorption may be one reason for vitamin D deficiency in many patients with PI, but there is little evidence of vitamin D malabsorption in patients with CD. Oral 25-OHD administration seems to be a useful therapeutic alternative to native vitamin D in patients with possible malabsorption and vitamin D deficiency.

Macrophages from rat livers with micronodular and macronodular cirrhosis differ with respect to mediator release and DNA-synthesis

BACKGROUND/AIMS

Liver macrophages play an essential role in necro-inflammatory liver damage which leads to fibrosis and cirrhosis. The aim of the present study was to compare the mediator release and the DNA synthesis of macrophages at an early and at a later stage of liver cirrhosis induced by thioacetamide.

METHODS

Liver macrophages were isolated by an enzymic digestion method, followed by elutriation. The release of reactive oxygen species and cytokines, and the synthesis of DNA were measured in cultivated cells.

RESULTS

The vitality of isolated macrophages from cirrhotic livers was always higher than 98%. The total yield of macrophages was less in micronodular cirrhotic livers and was markedly higher in macronodular cirrhotic livers when compared with age-matched controls. The cellular granules measured by sideward light scattering showed a shift to larger sizes in macrophages from micronodular cirrhotic livers when compared with the controls and the other experimental group. Macrophages from both cirrhosis groups exhibited a markedly higher unstimulated and lipopolysaccharide-stimulated IL-6 production than the controls. The release of TNF-alpha did not differ between controls and the experimental groups. Macrophages from macronodular cirrhotic livers produced higher amounts of nitric oxide but less superoxide anion radicals than the controls. DNA synthesis was 10-12-fold and 3-10-fold higher in macrophages from micronodular and macronodular cirrhotic livers, respectively, when compared with the age-matched controls.

CONCLUSIONS

The data presented provide evidence that it is possible to isolate and to cultivate macrophages from livers with high yield and vitality at different stages of cirrhogenesis. Our results clearly demonstrate functional differences between macrophages from livers with micro- or macronodular cirrhosis; this finding may be important for the pathogenesis or perpetuation of the cirrhogenetic process.

[Safe handling of the laryngeal mask airway in eye surgery]

BACKGROUND

We prospectively used the laryngeal mask airway (LM) in eye surgery to evaluate: 1) the limits of safe handling; 2) the feasibility of its use in long operative procedures, and 3) whether patients with higher anaesthetic risk (hypertension, asthma, children) may profit from the LM.

METHODS

In 792 patients leak pressure, cuff volume, duration of anaesthesia, and complications were noted; 33 were children under 10 years of age, 100 had hypertension or severe asthma. In 54 patients cuff volume was increased to measure its influence on leak pressure; in 241 leak pressure was also measured at the end of the procedure; in 31 cuff pressure was measured under standard conditions over time; in 7 dead space was evaluated with the BANALYZER program; and in 300 blind endotracheal suction was attempted through the LM.

RESULTS

Limits for the safe use of the LM were a leak pressure < 12 cm H2O combined with insufficient spontaneous ventilation (CO2et > 7 vol.%; n = 14), dislocation with gastric inflation (n = 2), and bronchial secretions (n = 1), as blind suctioning of the trachea through the LM was possible in only 1 out of 300 attempts. These limits could be recognised before the start of the operation in most cases. Laryngospasm or closure of the glottis (n = 36, 4.5%) was treatable and did not necessitate abandoning the use of the LM. Mean leak pressure was 17.7 +/- 4.8 cm H2O, showing a comparable distribution in adults and in children and being improved mainly by position changes of the LM, but not by changes in cuff volume. No gas leak occurred when the individual peak inspiratory pressure was equal to or lower than the measured leak pressure except in children. Dead space was almost halved by the LM compared to a face mask (90 +/- 13 vs. 162 +/- 31 ml; P < 0.05), allowing spontaneous breathing to be adequate even when manual assistance of ventilation was not possible (n = 14, 1.8%). In patients with sufficiently high leak pressures, the LM was safely used for long operations (up to 240 min), as leak pressure did not change over time. When only a low leak pressure could be achieved, deep breaths could be delivered by prolongation of the inspiratory time, thereby preventing atelectasis if tidal volume was limited. Cuff pressure rose to about 100 cm H2O within 60 min and should be monitored. In children, air was aspirated intermittently out of the stomach in procedures longer than 30 min; in adults, we monitored and buffered gastric contents where necessary. In patients at risk, the LM stimulates the circulation and bronchial reactivity less than an endotracheal tube. Children could be discharged earlier from the recovery room (0.45-1.5 h vs. > or = 2 h after neuromuscular relaxation and intubation).

CONCLUSION

Limits for the use of the LM in eye surgery are delineated. Within these limits, the LM offers control over the airway comparable to that of an endotracheal tube with less stimulation. The LM has to be applied by an experienced user, and has advantages in eye surgery.

Focally enhanced gastritis: a frequent type of gastritis in patients with Crohn's disease

BACKGROUND & AIMS

Gastric histology is not well studied in patients with Crohn's disease. The aim of this study was to analyze the histological appearance of gastric mucosa in patients with Crohn's disease.

METHODS

In a prospective study, biopsy specimens taken from the antrum and body of 75 patients with known Crohn's disease of the large and/or small bowel and 200 Crohn's disease-free controls were evaluated by histology and immunohistochemistry.

RESULTS

Helicobacter pylori-associated gastritis was found in 25 patients with Crohn's disease (33.3%) and 78 controls (39%). In H. pylori-negative patients with Crohn's disease, a characteristic type of gastritis was found in antral biopsy specimens of 36 patients (48%) and in body biopsy specimens of 18 patients (24%). It was characterized by a focal infiltration of CD3+ lymphocytes, CD68R+ histiocytes, and, in 80% of cases, of granulocytes. Granulomas were found in 11 patients. Overall, granulomas and/or focally enhanced gastritis were observed in 76% of H. pylori-negative patients with Crohn's disease and in 0.8% of controls. There were no correlations between the occurrence of focally enhanced gastritis and clinical and laboratory findings.

CONCLUSIONS

Focally enhanced gastritis is common in Crohn's disease. Its recognition should guide the clinician into further investigations in patients not yet known to have Crohn's disease.

Whipple's disease: comparison of histology with diagnosis based on polymerase chain reaction in four consecutive cases

BACKGROUND

Polymerase chain reaction (PCR) based detection of species specific sequences of the 16S rRNA gene of Tropheryma whippelii is a recently described method for diagnosis of Whipple's disease.

AIMS

Comparison of histology with PCR in mucosal samples of patients with Whipple's disease before, during, and after treatment. Detection of T whippelii in peripheral blood mononuclear cells as a non-invasive test for infection.

METHODS

Four consecutive patients with histologically proven Whipple's disease were studied prospectively.

RESULTS

In untreated patients biopsy specimens taken from regions with PAS positive macrophages gave a positive result with PCR for T whippelii; however, a PCR signal was also found in tissue biopsy specimens from mucosal regions with negative histology. In two of the patients the PCR performed with nucleic acids extracted from peripheral blood mononuclear cells was positive. After treatment with sulfamethoxazole/trimethoprim the PCR became negative after one month in two patients and after two months in the third patient treated, whereas PAS positive macrophages were found throughout the treatment period in two patients and disappeared in only one of them thereafter.

CONCLUSIONS

Detection of T whippelii specific sequences based on the PCR is useful to confirm the diagnosis, is able to detect a positive signal in samples taken from histologically negative mucosal areas, and can be used to monitor treatment. The PCR can sometimes be positive in peripheral blood mononuclear cells, but this cellular compartment cannot be taken as a substitute for duodenal biopsy specimens in the diagnosis of Whipple's disease.

Analysis for microsatellite instability and mutations of the DNA mismatch repair gene hMLH1 in familial gastric cancer

We examined 30 gastric-cancer patients with a varying degree of family history of stomach cancer and/or synchronous gastric tumors for microsatellite instability. We observed microsatellite instability at at least 1 of 8 loci tested in tumors of 14/30 patients; of these 14, 8 had single locus alterations and 6 had alterations at at least half of the 8 loci. Among the patients with microsatellite instability at > or = 4 loci, 3 patients showed a strong familial clustering of gastric cancer. Mutation analysis of the DNA mismatch repair gene hMLHl on paired non-tumorous and tumor DNA from 10 patients, 6 with microsatellite instability at > or = 4 loci and 4 with an alteration at one locus, revealed a novel missense mutation, present in the normal and tumor DNA of one patient with microsatellite instability at multiple loci in his tumor. His family history of cancer included one second-degree relative affected with gastric cancer. These data suggest that germline mutations in the hMLHl gene occur in some gastric-cancer patients and that in the majority of cases microsatellite instability in gastric tumors may be due to defects in other genes responsible for DNA replication fidelity than the hMLHl.