A vascular hypersensitivity model of acute multifocal gastrointestinal infarction

Isolated ACTH deficiency associated with Crohn's disease

We report a case of a 37-yr-old man with a 11-yr history of Crohn's disease (CD), who presented with mucous diarrheas of 1-week duration and a 3-month history of anorexia, increasing fatigue and weight loss of 7 kg. The patient was treated with sulfasalazine 3 g/day until 2 weeks prior to the present admission, when he reduced the dose to half as he considered the drug responsible for his symptoms. Despite aggressive iv rehydration and resolution of diarrheas with an increase in sulfasalazine dose, the patient remained hemodynamically unstable, while laboratory results showed anemia, hypoglycemia, hypertransaminasemia and hyponatremia with marked natriuresis. Thyroid function tests were consistent with primary hypothyroidism, without evidence of autoimmunity. Further laboratory investigation revealed a low basal cortisol and undetectable ACTH with preserved secretory responses of the other trophic pituitary hormones, establishing the diagnosis of isolated ACTH deficiency. Hydrocortisone replacement treatment induced a clinical and laboratory improvement. The autoimmune basis of isolated ACTH deficiency is discussed in association with the presumed contribution of immunologic reactions in the pathogenesis of CD. However more evidence is needed before isolated ACTH deficiency is added to the list of extraintestinal manifestations of CD.

Immunohistochemical expression of FHIT gene product in inflammatory bowel disease: significance and correlation with clinicopathological data

OBJECTIVE

To investigate the expression of Fhit protein in 53 patients with ulcerative colitis and Crohn's disease, as well as in 13 ulcerative-colitis-associated adenocarcinomas, and its eventual relationship with clinicopathological data and response to therapy.

MATERIALS AND METHODS

We performed immunohistochemistry in archival material of formalin-fixed, paraffin-embedded tissues using the anti-Fhit antibody and the streptavidin-biotin peroxidase method.

RESULTS

In 35/38 cases of ulcerative colitis, Fhit protein (pFhit) was absent or reduced. In the remaining three cases, it was expressed normally. In 12/15 cases of Crohn's disease, pFhit was absent or reduced, as it was in 4/13 cases of ulcerative-colitis-associated adenocarcinoma. Statistically significant differences of pFhit expression were observed between the active phase and the chronic healed phase of ulcerative colitis, and between the active phase and the normal colon mucosa. Also, statistically significant differences of pFhit expression were observed between (1) the resolving phase of ulcerative colitis and normal colon mucosa, (2) the chronic healed phase and normal colon mucosa, and (3) Crohn's disease and normal colon mucosa. Interestingly, a statistically very significant difference in pFhit expression was noticed between ulcerative colitis and ulcerative-colitis-associated adenocarcinoma.

CONCLUSIONS

Our results show that immunohistochemical expression of pFhit is completely absent or very reduced in idiopathic bowel disease (IBD) as well as in several ulcerative-colitis-associated adenocarcinomas in north-western Greece. These findings suggest that the FHIT gene might be involved in IBD and in a subgroup of ulcerative-colitis-associated carcinogenesis, although larger series should be tested.

Depressant effects of hypoxia and hypoglycaemia on neuro-effector transmission of guinea-pig intestine studied in vitro with a pharmacological model

1. Since intermittent ischaemia may play an important role in the aetiology of Inflammatory Bowel Disease, particularly Crohn's Disease, a pharmacological model of neuronal ischaemia was applied to guinea-pig isolated intestinal preparations to mimic the acute effects of reduced blood flow on intestinal motility. 2. Neuro-effector transmission and smooth muscle performance were examined in myenteric plexus-longitudinal muscle preparations of guinea-pig ileum exposed to sodium cyanide (NaCN), in order to inhibit oxidative phosphorylation, or to iodoacetic acid (IAA), to block glycolysis. Comparisons were made with the effects due to simple deprivation of oxygen or glucose. 3. Depression of cholinergic neuro-effector transmission induced by hypoxia or NaCN (effective concentration range 0.1-3 mM), given as separate treatments, singly or repetitively over 60-90 min, were apparent within 30 s and were reversible. The maximum inhibition was 90% and the IC50 for NaCN was 0.3 mM. A conspicuous component of these inhibitions was prejunctional. 4. Non-cholinergic neuro-effector contractions were inhibited by up to 90% by anoxia or NaCN but recovery was incomplete and slower than with cholinergic contractions. 5. Glucose-free solutions also caused a reversible failure of cholinergic neuro-effector transmission but of slower onset. In contrast, IAA (0.06-1 mM) abolished contractions irreversibly, apparently by a direct depressant effect on smooth muscle contraction. Unlike NaCN, IAA caused an initial potentiation of electrically-induced contractions, partly by a prejunctional potentiation of cholinergic neuro-effector transmission. 6. It is concluded that a disruption of intestinal activity in pathological conditions associated with intestinal ischaemia may result from disturbances in the function of enteric neurones.

Crohn's disease: pathogenesis and persistent measles virus infection

The Inflammatory Bowel Disease Study Group at the Royal Free Hospital School of Medicine has tested the hypothesis that the primary pathological abnormality in Crohn's disease is in the mesenteric blood supply. Early morphological studies involved arterial perfusion-fixation and either resin casting and scanning electron microscopy or vascular immunostaining of resected intestine affected by Crohn's disease. Granulomatous and lymphocytic damage to intramural blood vessels, even in macroscopically normal areas, was observed. We put forward possible mechanisms by which a chronic ischemic process might account for many of the idiosyncracies of Crohn's disease. It was proposed that persistent viral infection of the mesenteric microvascular endothelium might underly this vasculitic process; based on certain behavioral characteristics of measles virus, including its tropism for the submucosal endothelium of the intestine, this agent was investigated further. This report reviews the preliminary evidence from both epidemiological and basic scientific data for persistent measles virus in the intestine of patients with Crohn's disease. Possible mechanisms for virus persistence and subsequent reactivation are discussed. In conclusion, we believe that Crohn's disease may be a chronic granulomatous vasculitis in reaction to a persistent infection with measles virus within the vascular endothelium. This granulomatous inflammation, perhaps aggravated by either a hypercoagulable state or mechanical stress, results in the clinical features of Crohn's disease.