Nitric oxide inhibitors ameliorate indomethacin-induced enteropathy in rats.

The role of nitric oxide (NO) synthase inhibitors in indomethacin (INDO) -induced enteropathy was investigated in male Sprague-Dawley rats. Rats were subcutaneously administered 5% sodium bicarbonate (controls), two doses of INDO 7.5 mg/kg, and three different inducible NO synthase (iNOS) inhibitors at various concentrations 24 hr, apart; aminoguanidine (AG), guanidinoethyldisulfide (GED), and n-(3-aminomethyl)benzylacetamidine (1400W). Rats were killed four days after the initial injection and small intestinal mucosa was assayed for myeloperoxidase (MPO) activity and iNOS expression by western blot analysis. Serum nitrite/nitrate (NOx) concentration was measured colorimetrically. INDO produced acute ulcers along the mesenteric border from the ileum to proximal jejunum. Rats treated with AG (25 and 50 mg/kg), GED (2.5 mg/kg), and 1400W (0.1 mg/kg) showed decreased total ulcer length and MPO activity by 51, 72, 53, and 61% and by 58, 88, 68, and 70%, respectively, compared to INDO alone. All inhibitors similarly reduced INDO-enhanced serum NOx concentrations to its basal levels. Significant iNOS expression was detected in INDO-treated rats, but the inhibitors did not alter iNOS expression. Our data suggest that NO derived from iNOS may be a key factor in the pathogenesis of acute INDO-induced enteropathy in rats.

Expandable metal stents in achalasia--is there a role?

OBJECTIVE: Achalasia is treated with pneumatic dilation or myotomy, and botulinum toxin injections are occasionally used. We review our community's experience with expandable metal stents in six patients who failed medical treatment or were poor surgical candidates. METHODS: Eight stents were placed in six patients between July 1995 and November 1997. Four patients had achalasia and two pseudoachalasia. Four patients underwent successive botulinum toxin injections. One patient only agreed to periodic Maloney dilatations or a stent. Pneumatic dilation was performed in one patient and considered high risk in the rest. All were poor surgical candidates. Three different stents were used: Gianturco Rosch Z stent, Wallstent I, and Wallstent II. RESULTS: One-month mortality and morbidity were 33% and 50%, respectively. Two patients were asymptomatic on a liquid diet for > or =6 months but required repeat endoscopy for recurrent dysphagia because of food bolus impaction and proximal stent migration in each. CONCLUSIONS: Expandable metal stents in achalasia or pseudoachalasia do not provide sustained symptom relief, and their use is associated with unacceptably high morbidity and mortality. We do not recommend the use of these devices in patients who have failed medical therapy or who are poor surgical candidates.

Smoking and peptic ulcer in the Helicobacter pylori era.

Before the recent understanding of the central importance of Helicobacter pylori in the pathogenesis of peptic ulcer disease, smoking had been regarded as an important contributor to the cause and perpetuation of the disease. In this review, we find that (1) clinical observations indicate that smokers are more likely to develop ulcers, ulcers in smokers are more difficult to heal, and relapse of ulcer disease is more likely in smokers, (2) smoking adversely affects the gastroduodenal mucosal protective mechanisms, thus predisposing to ulcer disease, (3) smoking adversely affects gastroduodenal motility, allowing reflux of harmful duodenal contents into the stomach, (4) smokers appear to be at higher risk of becoming infected with H. pylori and this increased risk may be due to the adverse effects of smoking on antioxidants or the immune system that may interfere with the normal protection against H. pylori, and (5) once H. pylori is eradicated in smokers, they appear to be at no greater risk of peptic ulcer disease. We conclude that smoking in itself appears not to be an independent ulcerogen, but may act by augmenting the harmful effects of H. pylori, both by adversely affecting upper gastrointestinal mucosal protection and physiology and by increasing the risk of H. pylori infection. Thus, we recommend that appropriate advice to ulcer patients who smoke continues to be: stop smoking.

Extraintestinal non-Hodgkin's lymphoma presenting as obstructive jaundice in a patient with Crohn's disease.

We report the case of a 58-yr-old woman, previously diagnosed with Crohn's disease of the duodenum, who presented with jaundice and an epigastric mass. Diagnostic studies revealed an extraintestinal non-Hodgkin's lymphoma located near the head of the pancreas and causing obstructive jaundice. A review of the literature indicates the rarity of this association. We discuss the etiology, pathogenesis, and management of extraintestinal lymphomas in patients with Crohn's disease.

Immunoproliferative small intestinal disease in a 16-year-old boy presenting as severe malabsorption with excellent response to tetracycline treatment.

Immunoproliferative small intestinal disease (IPSID) is a rare lympho-proliferative disorder of the upper small intestine. It is considered a special form of MALT lymphoma with propensity to malignant transformation. This disorder is rare in pediatric literature. We report a case of IPSID in a 16-year-old boy with low-grade malignant transformation, presenting as severe malnutrition and a possible association with Helicobacter pylori. The patient responded well to an extended treatment with tetracycline and eradication of H. pylori.