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.     

Increased production of tumour necrosis factor-alpha interleukin-1 beta, and interleukin-6 by morphologically normal intestinal biopsies from patients with Crohn's disease

BACKGROUND: Increasing evidence points to a important role for inflammatory cytokines for the pathogenesis of Crohn's disease. AIM: To compare the secretion rate of tumour necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) by morphologically normal and inflamed intestinal mucosa from patients with Crohn's disease. RESULTS: Organ cultures of intestinal biopsy specimens taken from areas of affected mucosa from patients with Crohn's disease spontaneously produced increased amounts of TNF-alpha, IL-1 beta, and IL-6 compared with controls but also biopsy specimens taken in macroscopically and microscopically unaffected areas in the same patients. Concentrations of IL-1 beta and IL-6 measured in the supernatant fluid of biopsy cultures were positively correlated with the degree of tissue involvement measured by both endoscopic and histological grading. By contrast, TNF-alpha concentrations were not correlated to endoscopic and histological grading. CONCLUSIONS: These consistently raised TNF-alpha, IL-1 beta and IL-6 secretions by normal appearing mucosa from patients with Crohn's disease provide evidence for a sustained immune stimulation in Crohn's disease even in the absence of patent inflammation. The results shed a new light on the role of inflammatory cytokines in the onset of intestinal tissue damage in Crohn's disease and suggest that the range of intestinal lesions in Crohn's disease may be wider than suspected on the basis of regular endoscopic and histological examinations.     

Modulation of intestinal immune system by dietary fat intake: relevance to Crohn's disease

Gut-associated lymphoid tissue is the major inductive site of the mucosal immune system, which is functionally independent of the systemic immune system. Both the amount and type of dietary fat modulate intestinal immune function. Absorption of long-chain fatty acids stimulates lymphocyte flux and lymphocyte blastogenesis in intestinal lymphatics. Long-chain fatty acid absorption also significantly enhances migration of T lymphocytes to Peyer's patches, possibly due to up-regulation of adhesion molecules, such as alpha4-integrin and L-selectin. Lipoproteins are involved in stimulation of lymphocyte function by both receptor-dependent and independent mechanisms. However, unsaturated fatty acids at higher concentrations have a suppressive effect on cell-mediated immunity via eicosanoid release, receptor affinity changes or interactions with intracellular signal transduction. Fat absorption also influences various other cells in the intestinal mucosa: increased cytokine release from intestinal epithelial cells follows long-chain fatty acid absorption. In Crohn's disease, elemental diets and total parenteral nutrition often induce remission, possibly by reducing antigenic load on activated immune cells in the intestine and, thus, down-regulating hyperreactive CD4 cells. Dietary oleic acid supplements caused an immunological reversal effect in the intestinal immune system of animals fed an elemental diet. An excess of long-chain fatty acids in an elemental diet, therefore, may negate its beneficial effect on gut-associated lymphoid tissues in Crohn's disease. In contrast, supplemental dietary fish oil apparently tends to prevent relapse of Crohn's disease. Because dietary fat intake is closely associated with immunological function of the intestinal mucosa, careful manipulation of dietary fat can be important in management of this disease.     

Serum and intestinal fluid immunoglobulins and jejunal IgA secretion in Crohn's disease

Immunoglobulins in serum and proximal intestinal fluids and secretion of IgA by cultured jejunal mucosa were measured in 12 healthy subjects and 36 patients with Crohn's disease. Concentrations of IgA, IgG, IgM, and IgE in serum and intestinal fluids were similar in the two groups, except for increased serum IgA concentrations in the patients. Elevation of IgA and chronicity of disease were correlated, which suggests that the IgA alteration was a response to duration of disease rather than a primary pathogenetic factor. IgA secretion by cultured jejunum was similar in control and patient groups. Thus, no evidence was found that abnormalities of secretory immunoglobulins are pathogenetically involved in Crohn's disease.     

Bile acid metabolism and plasma protein turnover in Crohn's disease

Postprandial duodenal bile acids, intestinal protein loss, and albumin and IgG turnover were studied in 19 non-operated patients with Crohn's disease. A lesion of the terminal ileum was present in 18 of 19 patients, either alone or associated with regional colitis. Identical bile acid studies were made in a control group of 20 patients with chronic diarrhoea of undetermined origin. Duodenal bile acid concentration was decreased in 9 of 19 patients with Crohn's disease, and in 5 of 20 patients with unexplained diarrhoea. The glycine/taurine-ratio was increased in 8 of 17 patients with Crohn's disease, but in only one of the 20 control patients. Abnormal intestinal protein loss was present in 13 of 14 patients with Crohn's disease. The fractional catabolic rate of albumin and IgG was increased in all 17 cases of Crohn's disease studied, except the patient with no protein loss. A statistically significant and positive correlation was observed between glycine/taurine-ratio and fractional catabolic rate of both albumin and IgG. No patient with Crohn's disease harboured an abnormal bacterial flora in the proximal small intestine. It is concluded that, in the absence of abnormal bacterial flora in the proximal jejunum, the glycine/taurine-ratio is more valuable as an indicator of terminal ileopathy than postprandial duodenal bile acid concentration in nonoperated patients with terminal ileitis. Abnormal intestinal protein loss and increased catabolic rate of albumin and IgG are practically always present in active Crohn's disease and are strong evidence of an organic gastrointestinal lesion in patients with normal radiographic findings.     

Increased cell proliferation characterizes Crohn's disease

Patients with long-standing Crohn's disease (CD), a chronic inflammatory intestinal disease, are at increased risk for intestinal cancer. The neoplasia likely results, in part, from deregulated cell proliferation, which allows mutations to become fixed in the crypt progenitor cells. We postulated that tissues derived from patients with CD would exhibit increased mucosal proliferation. Therefore, we examined specimens from 27 consecutive patients with chronic CD with a monoclonal antibody directed against the proliferation marker, Ki-67. The tissues were evaluated histologically, and the Ki-67 immunostaining patterns were recorded. The antibody to Ki-67 stained the bases of the crypts in both the small and large intestines. The mean number of Ki-67 immunoreactive cells in the normal crypt was 34.1 versus 95.1 in the regenerative mucosa and O in areas of pyloric metaplasia (P < .00001). Ki-67 staining of the mucosa of patients with CD confirmed that cell proliferation is markedly increased and that the replicating compartment of each crypt during regeneration is expanded. We concluded that the increased cell proliferation might predispose the mucosa to mutational events, thereby increasing the cancer risk in these patients. The lack of proliferation in areas of pyloric metaplasia might represent a mucosal adaptive response of the lower crypt that decreases the number of cycling cells vulnerable to genetic damage. Furthermore, growth factors produced by these cells might promote healing of the damaged mucosa.     

Number, fixation properties, dye-binding and protease expression of duodenal mast cells: comparisons between healthy subjects and patients with gastritis or Crohn's disease

There is an accumulation of evidence to suggest that mast cells may play a key role in gastrointestinal inflammation. We have investigated the numbers and heterogeneity in staining properties of mast cells in biopsies of the duodenum of normal subjects (n = 10), and of normal duodenum from patients with Crohn's disease of the ileum and/or colon (n = 7) or with Helicobacter-associated gastritis of the antrum/corpus (n = 6). In normal donors, two subsets of mast cells, one located in the duodenal mucosa and the other in the submucosa, were clearly distinguished by their morphology and dye-binding properties. Whereas submucosal mast cells stained metachromatically with Toluidine Blue after neutral formalin fixation and emitted a yellow fluorescence after staining with Berberine sulphate, those in the mucosa were invisible using these stains. In patients with gastritis or Crohn's disease, there were marked changes in the numbers of mucosal mast cells compared with control subjects even though the duodenal biopsies were from apparently uninvolved tissue. Gastritis was associated with increased mucosal mast cell numbers (controls: 187 +/- 23 cells mm-2; gastritis: 413 +/- 139 cells mm-2; p = 0.0004), but mean mucosal mast cell counts in the uninvolved duodenum of Crohn's patients were actually decreased (34 +/- 30 cells mm-2, p = 0.0147). The clear differentiation between mucosal and submucosal mast cells on the basis of metachromasia with Toluidine Blue was not seen in biopsies from the patients with gastritis or Crohn's disease. Previous studies which have suggested that there are no distinct mucosal and submucosal mast cell subsets in the human intestine may, therefore, have been affected by the use of tissue from diseased subjects. Heterogeneity in the expression of mast cell tryptase and chymase was seen by immunohistochemistry using specific antibodies, but the relative numbers of mast cell subsets were critically dependent on the methods used. Using a sensitive staining procedure, the majority of mucosal mast cells stained positively for chymase as well as for tryptase, an observation confirmed by immunoelectron microscopy and immunoabsorption studies. Our findings suggest that early stages in intestinal inflammation may be reflected in changes in mast cell numbers and in their staining properties, and call for a reappraisal of mast cell heterogeneity in the human intestinal tract.     

Cellular immunity in patients with non-specific inflammatory bowel disease for an extended period after surgery

The study was aimed at investigating the expression of HLA-DR, CD4, CD8, CD56 surface antigens on peripheral blood lymphocytes in patients with non-specific inflammatory bowel diseases in the period of 1-5 years after the surgical procedure. The percentage of rosette forming T-cells in the theophylline test and skin reaction to mycotic and bacterial antigens were assessed simultaneously. The experiment included group of 12 patients (aged 5-55), treated surgically because of Crohn's disease or ulcerative colitis. The lymphocytes' surface antigens were examined by means of monoclonal antibodies and the APAAP procedure. Significantly increased (p < 0.001) percentage of lymphocytes with HLA-DR surface antigens and significantly decreased (p < 0.002) percentage of lymphocytes with CD8 surface antigens were observed in patients with non-specific inflammatory bowel diseases. In 6 of 12 patients the skin test results were negative. The clinical symptoms, which may suggest the maintaining inflammation of the intestinal mucosa were found in 50% of patients examined after surgical procedure because of Crohn's disease. The results suggest there are significant disturbances of cellular immunoreactivity parameters in patients with non-specific inflammatory bowel diseases. It may be one of the causes, which maintain the chronic inflammation of the intestinal mucosa and favour disease recurrence. The cellular immunoreactivity disturbances demonstrated in this study may be the result of the still persisting intestinal mucosa. Inflammation, in spite of deficiency of synonymous clinical symptoms indicating the disease recurrence.     

Oral contraceptive use and myocardial infarction

Inflammatory bowel disease (IBD) denotes chronic inflammatory disorders of gastrointestinal tract of unknown etiology that comprises 2 major groups: ulcerative colitis (UC) and Crohn's disease (CD). Disregulation of the intestinal immune system both at humoral and cellular level constitutes an important element in the multifactorial pathogenesis of IBD. The expression of pro-inflammatory cytokines, most notably IL-1, IL-6, TNF-alpha and chemokines (IL-8, ENA-78, MCP-1, RANTES) in intestinal mucosa from IBD patients is markedly enhanced, however, it is not always accompanied by increases in cytokines' serum levels. In IBD also significant changes occur in the tissue expression of immunoregulatory cytokines: increased levels of IL-2 mRNA and IFN-gamma mRNA, and decreased expression of IL-4 were found in affected intestinal mucosa. Chronic intestinal lesions of patients with Crohn's disease are associated with a Th1 type cytokine profile. The clinical effectiveness of anti-TNF-alpha antibodies and of IL-10 has been demonstrated in steroid-refractory Crohn's disease patients. The data demonstrating the role of cytokines in the pathogenesis of IBD should be carefully analyzed because of limitations imposed by the patient- and sample-related parameters. Further investigations will clarify the significance of the impairments in cytokine network for the initiation and progression of the IBD.     

Tumour necrosis factor alpha and interleukin 1beta in relapse of Crohn's disease

BACKGROUND: Concentrations of proinflammatory cytokines are increased in the intestinal mucosa of patients with active Crohn's disease. Experimental immunotherapeutic interventions with anticytokine agents in refractory Crohn's disease show that tumour necrosis factor alpha (TNF alpha) may be an important mediator of inflammation. We investigated the relation between production of TNF alpha and interleukin 1beta by mononuclear cells of the colonic lamina propria in patients with remitting Crohn's disease and the risk of relapse. METHODS: We followed up 137 patients with Crohn's disease in steroid-induced remission for 1 year. Secretion of proinflammatory cytokines (tumour necrosis factor alpha [TNF alpha] and interleukin 1beta) was assessed after short-term culture of human lamina propria mononuclear cells. FINDINGS: Increased secretion of TNF alpha and interleukin 1beta were predictive for acute relapses within the next year. Site and extent of disease, baseline demographics, and serum acute-phase proteins had little predictive value. INTERPRETATION: TNF alpha is important as a target molecule for immune interventions in Crohn's disease. The capacity to produce TNF alpha or interleukin 1beta may identify patients who would benefit from anti-inflammatory remission maintenance.     

The role of the mts1 gene in the metastatic process

The operation notes and pathology records of 294 consecutive patients who had right hemicolectomy for Crohn's disease were reviewed. A Meckel's diverticulum was found in 17 (5.8%) of these patients, 2-3 times the expected rate in the general population. At least 50% of diverticula in the normal population contain heterotopic mucosa, but none was found in those diverticula that were examined from this group. The increased prevalence of Meckel's diverticulum in patients with Crohn's disease confirms previous anecdotal reports, but the cause for the increased frequency remains unexplained. The significance of this finding is discussed.     

Science, technology and health literacy for the 21st century. A future for dentistry. Percy T. Phillips Memorial Lecture

Group II phospholipase A2 has been proposed to play an important role in the pathophysiology of inflammatory bowel diseases. This enzyme has also been linked to host defence mechanisms against bacteria. The current study aimed at measuring the mass concentrations of group II phospholipase A2 in serum and colonic mucosa of patients with Crohn's disease of different severity and of appropriate control patients without any inflammatory disease. The activity of the disease was determined by clinical factors (the simple index score) and endoscopic and histological scoring. The mass concentration of group II phospholipase A2 was measured by a time-resolved fluoroimmunoassay. The mass concentrations of group II phospholipase A2 in serum and colonic mucosa were significantly higher both in patients with active and inactive Crohn's disease when compared with controls. There was statistically significant difference in the mass concentration of group II phospholipase A2 in colonic mucosa but not in serum between inactive and active Crohn's disease. The current results indicate that the mass concentration of group II phospholipase A2 is increased in serum and colonic mucosa of patients with Crohn's disease and that the latter is associated with the degree of the inflammatory activity in the intestinal wall. These results support the idea that group II phospholipase A2 is involved in the local and generalised pathological processes of Crohn's disease.     

Photoaddition of ruthenium(II)-tris-1,4,5,8-tetraazaphenanthrene to DNA and mononucleotides

The purpose of this study was to show if inflammatory cells within healthy or diseased human intestinal mucosa produce some regulatory neuropeptides. First, inflammatory cells were isolated from the intestinal lamina propria of 11 patients with ulcerative colitis or Crohn's disease. Also collected were cells from anatomically normal intestine derived from five patients requiring bowel resection for diseases not related to inflammatory bowel disease. Extracts of these isolated cells contained authentic substance P (SP) and vasoactive intestinal peptide (VIP) as shown by RIA and their elution profiles on HPLC. Immunostaining of cells from nine of 13 additional patients localized immunoreactive SP and VIP to secretory granules within most mucosal eosinophils. No other cell types stained positive. Messenger RNA encoding SP and VIP was localized to lamina propria eosinophils by in situ hybridization. Mucosa inflammatory cells, from eight of nine more patients, cultured in vitro, released detectable amounts of VIP, but not SP. It is concluded that intestinal eosinophils produce SP and VIP. Since the eosinophils store and release more VIP than SP, it is possible that VIP is the preferred secretory product.     

Interleukin-12 expression is focally enhanced in the gastric mucosa of pediatric patients with Crohn's disease

The stomach is frequently involved in children suffering from Crohn's disease (CD). Diagnosis of specific gastritis may be difficult when granulomas are absent. We have used in situ hybridization to examine the expression of interleukin (IL)-12, a key cytokine in the Th1 response. IL-12 p35 and p40 antisense probes were used to examine ileal specimens from 9 children with CD and gastric biopsies from 24 children (13 with CD, 6 with Helicobacter pylori chronic gastritis, and 5 with a normal gastric mucosa). In all patients with CD, many clusters of IL-12-positive cells were present in the lamina propria. This was the case in the ileal specimens as well as in gastric mucosa showing granulomatous gastritis or nongranulomatous gastritis. The same distribution patterns were found for the IL-12 p35 and p40. In three patients with Helicobacter pylori gastritis, few scattered IL-12-positive cells were found. No positive cells were found in the normal gastric mucosa. The focally enhanced IL-12 expression in the gastric mucosa of pediatric patients with CD, with or without specific lesions, suggests that both are indeed linked to the disease and supports the major part of IL-12 in initiating and maintaining of the cascade resulting in the Th1 responses.     

Abnormal mucosal glycoprotein synthesis in inflammatory bowel diseases is not related to cigarette smoking

Patients with ulcerative colitis are usually non- or ex-smokers in contrast to Crohn's disease where smoking is common. Abnormalities of quantity and quality of intestinal mucus have been postulated in the pathogenesis of these diseases. It is possible that smoking habit may exert its effects via changes in mucus in inflammatory bowel disease. We have therefore studied incorporation of N-acetylglucosamine into synthesized colonic mucin in explants from 85 controls with normal colonoscopic appearances and histology, including 27 smokers and 58 nonsmokers, 36 patients with ulcerative colitis and 19 with ileocolonic Crohn's disease over 24 h in tissue culture. Incorporation of N-acetylglucosamine into normal explants was 31.3 +/- (SD) 7.1 dpm/microgram biopsy protein, incorporation was increased in patients with active Crohn's disease (mean 41.2 +/- (SD) 10.4 dpm/microgram biopsy protein, p = 0.003), decreased in inactive ulcerative colitis (mean 24.1 +/- 7.8 dpm/microgram biopsy protein, p = 0.0006) but normal in active ulcerative colitis (mean 35.0 +/- 13.8 dpm/microgram biopsy protein, p = 0.44). No significant relationship was found between cigarette smoking habits and mucus synthesis in controls with normal mucosa (nonsmokers, n = 58, mean 31.0 +/- (SD) 7.52 dpm/microgram biopsy protein; smokers, n = 27, mean 31.8 +/- (SD) 6.1 dpm/microgram biopsy protein, p = 0.9). This study shows that mucus glycoprotein synthesis is reduced in inactive ulcerative colitis, rising to normal levels in active disease and that synthesis is increased in Crohn's disease. There is no effect of smoking on mucus synthesis by control biopsies suggesting that the differences seen in inflammatory bowel disease are not related to cigarette smoking.     

Expression of adhesion molecules and HLA-DR by macrophages and dendritic cells in aphthoid lesions of Crohn's disease: an immunocytochemical study

The phenotypes and ultrastructure of macrophages and dendritic cells in aphthoid lesions of the colon were immunocytochemically observed in patients with Crohn's disease. Biopsy specimens were endoscopically obtained from both aphthoid and advanced lesions in Crohn's disease patients. Biopsy specimens obtained from patients with infectious colitis and from normal individuals served as controls. Aphthoid lesions contained densely aggregated CD68+ macrophages, which were surrounded by numerous ID-1+ dendritic cells. In the normal controls and infectious colitis patients, however, a few scattered CD68+ macrophages and ID-1+ dendritic cells were noted beneath the surface epithelium. CD3+ lymphocytes were significantly increased in both aphthoid and advanced lesions of Crohn's disease, but the CD4/CD8 ratio was similar in all groups studied. The double immunoperoxidase staining method revealed that both CD68+ macrophages and ID-1+ dendritic cells in the aphthoid lesions simultaneously expressed ICAM-1 and HLA-DR antigens. Electronmicroscopic observation revealed that CD68+ macrophages had numerous vesicles and lysosomal granules and few projections, and that ID-1+ dendritic cells had appreciable cytoplasmic protrusions with a few vacuoles. These findings suggested that the colonic mucosa in Crohn's disease contained two types of macrophage/dendritic cells in the same lineage that expressed intercellular adhesion molecules and class-II MHC antigens. It also appeared that the aphthoid lesions of Crohn's disease featured an increase in macrophages and dendritic cells consistent with immunological activation.     

Changes in plasma and colonic mucosa fatty acid profiles in rats with ulcerative colitis induced by trinitrobenzene sulfonic acid

Polyunsaturated fatty acids have a key role in the pathogenesis of inflammatory bowel disease since some of the arachidonic acid-derived eicosanoids have been found to be increased in inflamed intestinal mucosa in the acute phase of human disease. The aim of this study was to prospectively assess plasma and colon mucosa fatty acid patterns in rats with experimental ulcerative colitis. Twenty rats were treated with trinitrobenzene sulfonic acid and 20 with NaCl; two groups were killed after one week and two after two weeks to evaluate colon damage. Plasma was obtained by aortic puncture and colonic mucosa was scraped off and the fatty acid pattern was determined by gas-liquid chromatography. Total, saturated, and monounsaturated plasma fatty acids were significantly higher in both periods of ulcerative colitis as compared to controls. Plasma n-6 fatty acids were increased after treatment, but no significant changes were observed concerning to n-3 fatty acids. With regard to colon mucosa, saturated and monounsaturated fatty acids did not change because of the disease; however, n-6 fatty acids decreased in the first week and increased in the second week and n-3 fatty acids were increased. Changes on the fatty acid distribution in plasma did not parallel to those of colonic mucosa except for 22:6(n-3). We have also found that experimental ulcerative colitis induced by trinitrobenzene sulfonic acid reproduces many of the features related to changes in plasma and colon mucosa fatty acids observed in the human disease.     

Pyostomatitis vegetans and Crohn's disease. A specific association of 2 diseases

HISTORY AND CLINICAL FINDINGS: A 27-year-old man was referred to the dermatological out-patient clinic because of inflammatory changes in the oral mucosa of unknown cause. 5 months earlier he had been diagnosed as having Crohn's disease of the terminal ileum. On both sides of the buccal mucosa there were rough erythematous vegetations and disseminated miliary abscesses, which extended to the labial gingiva and the soft palate. Further physical examination was unremarkable. INVESTIGATIONS: Several inflammatory parameters were increased: C-reactive protein 100 mg/l, erythrocyte sedimentation rate 55/88 mm, eosinophilic cationic protein 35.8 ng/ml (normal range 2.3-16 ng/ml). White cell count was normal (7,25/nl), with a lymphocytopenia of 11.9%. There was no eosinophilia. Haemoglobin was reduced to 11.6 g/dl and the platelets raised to 526/nl. Smears of the oral mucosa showed no fungal, viral or bacterial infection. Biopsy revealed leucocytic microabscesses in the epithelium, granulation tissue and flat ulcerations with adjoining superficial necrotic zones. DIAGNOSIS, TREATMENT AND COURSE: The clinical and histological picture as well as the association with Crohn's disease (CD) suggested pyostomatitis vegetans (PV). The PV was treated with disinfectant mouth washes which improved the subjective findings. Budesonide was given for CD. CONCLUSION: PV is a rare and usually isolated condition, but it can also occur in association with a chronic gastrointestinal disease such as ulcerative colitis and Crohn's disease. The diagnosis of PV indicates a thorough gastroenterological investigation.     

Metabolism of 109Cd in rats fed normal and low-calcium diets

Growing male rats were fed purified diets that contained either 0.6% or 0.1% calcium to investigate the relationship of calcium intake to the uptake, tissue distribution, and excretion of 109Cd. An equal number of rats were fed either the 0.6 or 0.1% calcium diets for 4 wk before they were used for experiments. In the first experiment 11 rats from each dietary group were administered 5 muCi 109Cd by stomach tube and were then maintained in metabolism cages for 72 hr. Animals fed the low-calcium diet took up more 109Cd, as significantly higher levels of radioactivity were found in the intestinal mucosa, serum, lungs, liver, kidneys, and urine and a significantly lower level was found in the feces. Higher levels of 109Cd, associated with low-molecular-weight proteins that may be related to the absorption process, were found in the intestinal mucosa of the low-calcium group. In the second experiment 10 rats from each dietary group were administered 5 muCi 109Cd by subcutaneous injection and then maintained in a metabolism cage for 72 hr. No significant differences were found in the distribution or excretion of 109Cd except for the lungs where radioactivity was greater in the low-calcium group. The results of the study indicate that the enhanced cadmium toxicity observed in calcium-deficient animals exposed to the heavy metal is the result of an increased uptake from the small intestine.     

Tuberculous colitis mimicking Crohn's disease

Intestinal tuberculosis is a rare disease in western countries and may mimic a variety of gastrointestinal disorders. Here, we report the case of a 63-yr-old patient who presented with profuse bleeding from a deep rectal ulcer. Similar lesions were found in different parts of the colon. Multilocular colorectal carcinoma was suspected based on the macroscopic appearance. Histology, however, suggested Crohn's disease. Intestinal tuberculosis was initially ruled out by negative staining for acid-fast bacilli, mycobacterial culture, and polymerase chain reaction analysis. A treatment for Crohn's disease was started. Endoscopic reexamination revealed progressive disease with extensive ulcerations of the terminal ileum. Histopathological examination then revealed acid-fast bacilli in the colonic mucosa typical for mycobacterium tuberculosis infection. This case emphasizes the need to include intestinal tuberculosis in the initial differential diagnosis of ulcerative colorectal lesions also in the western population.