Angioedema of the small bowel caused by lisinopril

In conjunction with BMJ Case Reports, DTB will feature occasional drug-related cases that are likely to be of interest to readers. These will include cases that involve recently marketed drugs for which there is limited knowledge of adverse effects and cases that highlight unusual reactions to drugs that have been marketed for several years.

Successful treatment of ileal ulcers caused by immunosuppressants in two organ transplant recipients

Although gastroduodenal ulcers are common in solid organ transplant patients, there are few reports on multiple giant ulcers in the distal ileum and ileocecal valve caused by immunosuppressants Herein, we report on a liver transplant recipient and a renal transplant recipient with multiple large ulcers in the distal ileum and ileocecal valve who rapidly achieved ulcer healing upon withdrawal of sirolimus or tacrolimus and administration of thalidomide. In case 1, a 56-year-old man with primary hepatocellular carcinoma had received a liver transplantation. Tacrolimus combined with sirolimus and prednisolone was used as the anti-rejection regimen. Colonoscopy was performed because of severe abdominal pain and diarrhea at post-operative month 10. Multiple giant ulcers were found at the ileocecal valve and distal ileum. The ulcers healed rapidly with withdrawal of sirolimus and treatment with thalidomide. There was no recurrence during 2 years of follow-up. In case 2, a 34-year-old man with end-stage kidney disease received kidney transplantation and was put on tacrolimus combined with mycophenolate mofetil and prednisolone as the anti-rejection regimen. Twelve weeks after the operation, the patient presented with hematochezia and severe anemia. Colonoscopy revealed multiple large ulcers in the ileocecal valve and distal ileum, with massive accumulation of fresh blood. The bleeding ceased after treatment with intravenous somatostatin and oral thalidomide. Tacrolimus was withdrawn at the same time. Colonoscopy at week 4 of follow-up revealed remarkable healing of the ulcers, and there was no recurrence of bleeding during 1 year of follow-up. No lymphoma, tuberculosis, or infection of cytomegalovirus, Epstein-Barr virus, or fungus was found in either patient. In post-transplantation cases with ulcers in the distal ileum and ileocecal valve, sirolimus or tacrolimus should be considered a possible risk factor, and withdrawing them or switching to another immunosuppressant might be effective to treat these ulcers.

The Impact of Resveratrol on Oxidative Stress Induced by Methotrexate in Rat Ileum Tissue: Evaluation of Biochemical and Histopathological Features and Analysis of Gene Expression

OBJECTIVE

The aim of this study was to assess the impact of resveratrol (RST) on oxidative stress induced by methotrexate in rat ileum tissue.

MATERIALS AND METHODS

Twenty-four rats were divided into 4 groups with 6 in each group. Each rat was orally administered the following every day for 30 days: group 1 (MTXG), methotrexate (MTX; 5 mg/kg); group 2 (RMTXG), MTX (5 mg/kg) plus RST (25 mg/kg/day); group 3 (RSTG), RST alone (25 mg/kg/day), and group 4 (controls), distilled water. After the rats had been sacrified, the ilea were removed for the assessment of malondialdehyde (MDA), total glutathione (tGSH) and glutathione peroxidase (GSH-Px). Gene expression analyses for interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and myeloperoxidase (MPO) were also performed. Hematoxylin and eosin-stained paraffin-embedded sections of the ileum were analyzed under a light microscope and the findings were recorded. Statistical analyses of the data were performed using one-way ANOVA.

RESULTS

The administration of MTX in group 1 yielded a higher level of MDA (8.33 ± 2.5 μmol/g protein, p < 0.001) and lower levels of tGSH (0.97 ± 0.29 nmol/g protein) and GSH-Px (5.22 ± 0.35 U/g protein, p < 0.001) compared to the other groups. MTX also increased IL-1β (40.33 ± 5.43 gene expression levels), TNF-α (6.08 ± 0.59) and MPO gene expression (9 ± 1.41) in group 1 compared to the controls (11.33 ± 2.07, 2.15 ± 0.33 and 3.43 ± 0.48, respectively, p < 0.001). The impact of RST on IL-1β, TNF-α and MPO gene expression induced by MTX was observed as a reversal of these findings (p < 0.05). Severe inflammation, damage to the villus epithelium and crypt necrosis was observed histopathologically in the MTXG group, whereas only mild inflammation was seen in the RMTXG group.

CONCLUSION

In this study, ileal damage caused by MTX was inhibited by RST.

Effect of bifidobacterium on defensin-5 expression in intestinal injury of preweaning rats

AIM: To investigate the protective effect of bifidobacterium in endotoxin-induced intestinal injury in preweaning rats.

METHODS: Preweaning rats were randomly divided into three groups (n = 40 for each): a control group (group C), a model group (group E) and a treatment group (group T). Both groups E and T were intraperitoneally injected with lipopolysaccharide (LPS) at a dose of 5 mg/kg (5 mg/L in normal saline), and group T was intragastrically administrated with bifidobacterium suspension (2.0 × 10⁹ CFU/mL, 0.5 mL each time, twice a day, until the end of the experiment) 7 d before LPS administration. Group C was intraperitoneally injected with normal saline. After intraperitoneal injection and intragastric administration, the rats were placed back to the initial cage to receive breast feeding. The rats were killed at 2, 6, 12, 24 or 72 h, respectively, after endotoxin or physiological saline injection to collect serum and ileal tissue samples. Myeloperoxidase (MPO) contents in serum and ileum were detected at different times, and expression of ileal defensin-5 mRNA was evaluated by reverse transcription-polymerase chain reaction.

RESULTS: Serum and ileal MPO contents in group E were significantly higher than those in group C (serum contents: 107.50 ± 17.70 vs 157.14 ± 24.67, P < 0.05; ileal contents: 1.03 ± 0.21 vs 1.57 ± 0.33, P < 0.05), which peaked at 12 h and 6 h, respectively. MPO contents in group T were significantly lower than those in group E (serum contents: 114.38 ± 24.56 vs 145.25 ± 23.62, P < 0.05; ileal contents: 1.25 ± 0.24 vs 1.57 ± 0.33, P < 0.05). The expression of defensin-5 mRNA in group E was significantly higher than that in group C (0.953 ± 0.238 vs 0.631 ± 0.146, P < 0.05), which peaked at 2 h, and then decreased gradually. The expression of defensin-5 mRNA in group T was significantly lower than that in group E (0.487 ± 0.149 vs 0.758 ± 0.160, P < 0.05) apparently in 24 h. The expression of defensin-5 mRNA at 2 h in group T was significantly higher than that in group C (0.824 ± 0.158 vs 0.631 ± 0.146, P < 0.05).

CONCLUSION: MPO and defensin-5 mRNA increase in preweaning rats with LPS-induced intestinal injury. Bifidobacterium protects the gut by inhibiting MPO activity, not by increasing defensin-5 secretion.

Adult idiopathic intussusception: a case report and review of the literature

Adult intussusception is a rare condition. Most of the cases are due to an organic lesion and unlike the incidence in children idiopathic forms are really exceptional, occurring at a rate of 5% of all cases. Whereas in children a main cause is seldom found, adult intussusception is usually characterised by the presence of a leading intraluminal benign or malignant lesion. The authors report their experience with a clinical case of ileocolic intussusception occurring in an 28-year-old white male. In spite of the patient's age, the clinical presentation was very typical with the classic triad of abdominal pain, blood per rectum and a palpable mass. Diagnostic tools, namely US and TC scan, together with colonoscopy confirmed the physical examination, so that surgery was initiated with a definite diagnosis of intussusception. A large polyp or a lymphoma were considered the possible leading causes. After right hemicolectomy, pathology revealed that there was no organic lesion and the bulging mass was caused only by oedema and haemorrhagic infiltration of the invaginated loop. The patient had been on antipsychotic drugs for several months and the possible explanation of the pathology was linked to altered peristalsis induced by the pharmacological agents he was taking. The authors compare their experience with the data reported in the literature, evaluating in particular the incidence, pathology, clinical presentation, diagnosis and treatment of adult intussusception.

[Effect of Ning Wei Kang Recipe extract on gastrointestinal motor function]

OBJECTIVE

To study the effect of Ning Wei Kang Recipe extract on gastrointestinal motor function.

METHODS

The effects of Ning Wei Kang Recipe extract on gastrointestinal motor function were studied in mice, rabbits, and isolated mesenterial intestines of guinea pig according to its effect on acetylcholine or barium chloride-induced contraction.

RESULTS

Ning Wei Kang Recipe extract could significantly decrease the propellent movement of medicine charcoal in the mesenterial intestine of mice (P < 0.01), inhibit the range and speed of mesenterial intestine of rabbits (P < 0.05, or P < 0.01), relax the contration of isolated mesenterial intestines of guinea pig induced by BaCl2 (P < 0.05). But it could not decrease the contration of isolated mesenterial intestines of guinea pig induced by acetylcholine (P< 0.05).

CONCLUSIONS

Ning Wei Kang Recipe extract can significantly inhibit the gastrointestinal motor function. It may be related to blocking positive ion-Ba2+ into gastrointestinal smooth muscle cell.

Microcirculatory changes in experimental mesenteric longitudinal ulcers of the small intestine in rats

Rats receiving intracolonic administration of indomethacin develop longitudinal ulcers on the mesenteric side of the small intestine that are similar to those seen in the acute phase of Crohn's disease. To investigate the causative role of microcirculatory disturbances and to elucidate the therapeutic effect of antioxidants on this enteropathy in rats, we serially evaluated changes in regional blood flow of the small intestine using laser Doppler perfusion imaging and the colored microsphere injection method. Both methods disclosed stepwise hyperperfusion limited to the mesenteric side of the small intestine following transient ischemia during the initial 30-60 minutes. In addition, both a radical scavenger and a radical production inhibitor significantly ameliorated the mesenteric longitudinal ulcers. We concluded that ischemia-reperfusion on the mesenteric side accompanying excessive production of radicals might be strongly involved in indomethacin-induced longitudinal ulcers of the small intestine in rats.

Down-Regulation of Hepatic Transporters for BSP in Rats with Indomethacin-Induced Intestinal Injury

Previous reports have demonstrated that an intestinal injury causes hypofunctions of the liver associated with down-regulations of cytochrome P450, but an influence on hepatic transporters remains unclear. Here, we tested hepatic transporter functions in a rat model of bowel injury using indomethacin (IDM). After administration of IDM (8.5 mg/kg, i.p., 3 d), the rats suffered the intestinal impairment indicated by a reduction of alkaline phosphatase activity in mucosa. In vivo pharmacokinetic experiments of bromosulfophthalein (BSP) showed that there was a reduction in its plasma elimination rate and cumulative biliary excretion in IDM-treated rats and systemic and biliary clearances reduced to nearly 50% of the control group. Protein expressions in plasma membrane and mRNA levels of organic anion transporting polypeptide 1b2 (Oatp1b2) and multidrug resistance-associated protein 2 (Mrp2), which play hepatic BSP uptake and biliary excretion, respectively, in the liver were significantly reduced following the IDM treatment. In portal plasma, the levels of proinflammatory cytokines were unchanged, while the level of nitric oxide metabolites (NO2- + NO3-) increased to 6.5-fold that of the control. The time-course on IDM treatment indicated that, firstly, intestinal injury was induced, the NO level increased, and the hepatic Oatp1b2 and Mrp2 expression began to fall followed by an increase in plasma ALT. In conclusion, IDM-induced injury to the small intestine causes the hypofunction of hepatic Oatp1b2 and Mrp2 independently on the hepatic impairment, and NO arising from bowel injury may be one of key factors for it through the remote effect.

[Ileal and right colonic strictures due to prolonged non steroidal anti-inflammatory drug intake]

Ileal and right colonic strictures due to long term NSAID intake are well known but rare. We report the case of a patient with rheumatoid arthritis presenting with one ileal, as well as a right and transverse colonic stricture. The latter two were treated by dilatation under colonoscopy, but due to an associated recurrence, and the necessity of treating the ileal stricture which was inaccessible, a transverse ileocolonic shunt was proposed under local anesthesia. Ileal and colonic strictures due to long term NSAID intake should first be treated, if possible, by discontinuing the drug, then by pneumatic dilatations and finally, if necessary, by surgery usually resection. The advantage of a gastrointestinal shunt is that it can be performed under local anesthesia in patients who are often in poor condition.

Development of next generation medical countermeasures to nerve agent poisoning

Medical countermeasures provide a key role in the UK integrated approach to chemical defence and are aimed at preventing or mitigating the effects of exposure to nerve agents. It is UK policy that medical countermeasures will be licensed products. Demonstration of efficacy relies on extrapolation of animal-derived data to man which means that species selection is extremely important. For the foreseeable future it is likely that a combination of pretreatment and therapy will be required to provide protection against nerve agent poisoning. There is a longer-term aspiration to develop a post poisoning-therapy which would reduce the reliance on pretreatment, prevent or mitigate the effects of exposure to all nerve agents and decrease the requirement for three autoinjectors. Immediate therapy comprising physostigmine (0.2mg/kg), hyoscine hydrobromide (4mg/kg) and HI-6 (93.6mg/kg) protected all animals against the lethal effects of a supralethal dose of GD, when given 1min after nerve agent poisoning in the absence of any pretreatment. In contrast when hyoscine hydrobromide was replaced with hyoscine methyl nitrate most of the animals died within 24h, whereas when an equal mixture of hyoscine hydrobromide and hyoscine methyl nitrate was used all the animals survived. None of these animals had an intussusception. It would not be possible to deliver these doses of HI-6 to a human from a single autoinjector device. Recent studies have shown that a lower dose of HI-6 (7mg/kg) which can be delivered via an autoinjector, in combination with physostigmine and hyoscine hydrobromide provides good protection against the lethal effects of a supralethal dose of GD. A number of animals died between 6 and 24h and had an intussusception. The surviving animals did not begin to regain weight until 48h after poisoning. In contrast when a mixture of hyoscine hydrobromide and hyoscine methyl nitrate was used, one animal died within 15min, the other animals all survived, regained weight from 24h and did not have an intussusception. These studies will now be extended to include other agents and will be taken forward to studies in non-human primates where the incidence of intussusception will be closely monitored.

Diaphragm disease of the ileum: a case report

Non-steroidal anti-inflammatory drugs induced diaphragm like lesions are a rare cause of small intestinal obstruction. They occur most commonly in elderly patients who have been consuming these drugs for prolonged periods for pain relief. We report the first case of ileal diaphragm disease from Asia. She responded well to localised resection of the diseased ileum. Intra-operative enteroscopy may be helpful in deciding the extent of intestinal resection.

Sirolimus-induced ulceration of the small bowel in islet transplant recipients: report of two cases

Sirolimus (SRL) has been used for most islet recipients over the past 5 years. It provides balanced immunosuppression in combination with low-dose calcineurin inhibitors, while avoiding corticosteroids. This regimen decreases the risk of nephrotoxicity, neurotoxicity and diabetogenicity. SRL has also been used selectively in clinical liver and kidney transplantation. A number of common side effects including anemia, leucopenia, thrombocytopenia, hypercholesterolemia, mouth ulceration, joint pain, extremity edema and impaired wound healing have been associated with the use of SRL. As SRL is used more frequently, evidence has been gathered on its rare but severe side effects. We report 2 patients who underwent islet transplantation and developed symptomatic small bowel ulceration that resolved after complete withdrawal of SRL. Although small bowel ulceration is rare, it can potentially progress to more serious complications if not treated adequately. Our experience highlights an uncommon but potentially serious adverse effect of high-dose SRL in islet recipients.

Diaphragm disease: complete small bowel obstruction after long-term nonsteroidal anti-inflammatory drugs use

Diaphragm-like stricture of the small bowel is an infrequent complication of the treatment of patients with nonsteroidal anti-inflammatory drugs (NSAIDs) and is part of the spectrum of diseases associated with NSAIDs injury. We report a patient with this condition who had used various forms of NSAIDs for over 20 years. Patient presented with abdominal pain and indigestion. Plain abdominal film revealed small bowel obstruction. Surgical resection of jejunum and proximal part of ileum identified dilated thickened hyperemic mucosa alternating with areas of small bowel fibrotic constriction. The mucosal surface showed multiple pink-tan mucosal folds (circumferential ridges) with focal hemorrhage and edema. Our findings support the local stimulation and damage and reparative process seen with NSAIDs use. A high degree of suspicion and awareness of diaphragm disease is necessary in those patients.

[Small bowel diaphragm disease associated with NSAIDs with histology of neuromuscular and vascular hamartoma. Case report and literature review]

Diaphragm disease (DD) induced by non-steroidal anti-inflammatory drugs (NSAIDs) and neuromuscular and vascular hamartoma (NMVH) are rare entities that can be difficult to recognize clinically, radiologically and pathologically. Both may cause small bowel obstruction and both reveal annular constrictions macroscopically. However, the 2 entities differ in that the constrictions are purely fibrous in DD whereas they have a hamartomatous histopathology in NMVH. We describe the case of a 76-year-old woman with a history of prolonged NSAID use who developed clinical features and gross pathology consistent with DD and histopathology of NMVH.

Inhibitory effect of fluvastatin on ileal ulcer formation in rats induced by nonsteroidal antiinflammatory drug

AIM: Nonsteroidal anti-inflammatory drugs (NSAIDs) cause gastrointestinal damage as one of their side effects in humans and experimental animals. Lipid peroxidation plays an important role in NSAID-induced ulceration. The aim of this study was to investigate the inhibitory effect of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors on the ulceration in small intestines of rats.

METHODS: The effects of three HMG-CoA reductase inhibitors, fluvastatin, pravastatin and atorvastatin on ileal ulcer formation in 5-bromo-2-(4-fluorophenyl)-3-(4- methylsulfonylphenyl) thiophene (BFMeT)-treated rats were examined. Antioxidative activity of the inhibitors was measured by a redox-linked colorimetric method.

RESULTS: Fluvastatin, which was reported to have antioxidative activity, repressed the ileal ulcer formation in rats treated with BFMeT an NSAIDs. However, the other HMG-CoA reductase inhibitors (pravastatin and atorvastatin) did not repress the ileal ulcer formation. Among these HMG-CoA reductase inhibitors, fluvastatin showed a significantly stronger reducing power than the others (pravastatin, atorvastatin).

CONCLUSION: Fluvastatin having the antioxidaitive activity suppresses ulcer formation in rats induced by NSAIDs.

A very rare consequence of steroid therapy: ileal perforation in a patient with familial mediterranean fever

Intestinal perforation rarely occurs in children with familial Mediterranean fever (FMF). When this does happen, it is the result of untreated intestinal obstruction caused by compression from peritoneal adhesions. Intestinal perforation is a well-known complication of steroid therapy in all ages. The duodenum is affected most frequently, but perforation may also occur in other parts of the small intestine and, very rarely, the colon. Intestinal wall changes that occur in chronic FMF may promote the harmful effects of steroids. Here we present an unexpected complication, ileal perforation, in an 8-year-old boy who was taking prednisolone for FMF-related arthritis.

[Indomethacin-induced ileal perforation]

We present two cases of indomethacin-induced perforation of the distal small intestine. Both patients were male and undergoing oral indomethacin therapy. Both presented acute abdomen with diffuse peritonitis secondary to perforations located in the antimesenteric border of the terminal ileum. Histopathological lesions of the intestinal wall showed transmural infiltration, congestion, and hemorrhage; their severity was related to higher doses and longer duration of indomethacin therapy.

Clofazimine enteropathy in a pediatric bone marrow transplant recipient

Clofazimine, previously used in the treatment of leprosy, is now used for treatment of Mycobacterium avium complex infection in patients with acquired immune deficiency syndrome, dermatologic disorders, and graft-versus-host disease. An 11-year-old boy developed a severe enteropathy 2 years after initiation of clofazimine treatment for graft-versus-host disease. Clofazimine enteropathy caused by crystal deposition can be life-threatening.

Diaphragm disease of the small bowel: a case without apparent nonsteroidal antiinflammatory drug use

BACKGROUND

Diaphragm-like strictures of the small bowel are an infrequent complication of the treatment of patients with nonsteroidal antiinflammatory drugs (NSAIDs).

STUDY

We report a patient with this condition in whom the use of NSAIDs was ruled out by both clinical history and objective blood testing of current aspirin use.

RESULTS

He reported a history of recurrent episodes of colic abdominal pain during the past 25 years; he underwent three surgical operations for this condition. Before these symptoms, he had an undefined abdominal process with diarrhea, weight loss, and diffuse edema, which resolved spontaneously without reaching a diagnosis.

CONCLUSIONS

We suggest that diaphragm-like strictures might be developed as a nonspecific response to different damaging insults to the intestine and are not necessarily associated with NSAID use.

Small-bowel perforation in very low birth weight neonates treated with high-dose dexamethasone

INTRODUCTION

Early postnatal treatment with high doses of corticosteroids may be effective in reducing the duration of mechanical ventilation in very low birth weight infants at risk for bronchopulmonary dysplasia. However, serious side effects may occur.

MATERIAL AND METHODS

A retrospective study on 5 very low birth weight neonates, mean (+/- SEM): gestational age range 27.5 +/- 2 weeks, mean birth weight (+/- SEM): 836 g +/- 169 referred between April 1997 and October 1998 from a single academic neonatal intensive care unit to our tertiary pediatric surgical center with the diagnosis of intestinal perforation. During the same period, 60 very low birth weight infants have been treated in that unit following a standardized protocol including surfactant for respiratory distress syndrome and high-dose dexamethasone to prevent bronchopulmonary dysplasia.

RESULTS

Pneumoperitoneum was diagnosed between 6 to 9 days after birth. Clinically, all babies remained surprisingly stable. An isolated ileal perforation, without sign of necrotizing enterocolitis, was found at laparotomy in each patient. A limited intestinal resection was performed, with primary end-toend anastomosis (3 cases) or with transient ileostomies (2 cases). Surgical outcome was favorable in all patients.

CONCLUSION

isolated intestinal perforation may be a complication of the preventive treatment of chronic lung disease with high-dose corticosteroids in very low birth weight infants. Conversely, corticosteroids may reduce the clinical signs and the multiple organ dysfunction associated with an abdominal drama, explaining the very good surgical prognosis of these newborns. Attention must be paid to an insidious pneumoperitoneum.

Role of biliary phosphatidylcholine in bile acid protection and NSAID injury of the ileal mucosa in rats

BACKGROUND & AIMS

We explored the role of biliary phosphatidylcholine (PC) in protection of the intestinal mucosa against bile salt (BS)-induced intestinal injury and how this property may be blocked by indomethacin (Indo), a nonsteroidal anti-inflammatory drug (NSAID) that is secreted into the bile.

METHODS

We performed in vivo studies in which bile was collected over a 2-hour period after rats were intragastrically administered Indo (25 mg/kg) or an equivalent volume of saline (controls). The bile samples (some of which were supplemented with PC) were then instilled into a loop of distal ileum of anesthetized rats. After a 30-minute exposure period, we measured the hemoglobin concentration of the ileal loop fluid, as an index of bleeding, and mucosal contact angles, as an index of surface hydrophobicity. A similar in vivo experiment was performed in which model bile containing 5 mmol/L each of the BS, sodium deoxycholate, PC, or Indo, alone and in combination, was instilled into ileal loops. In our in vitro test system, human erythrocytes were exposed to the above biliary constituents, and hemolysis was measured spectrophotometrically.

RESULTS

Bile from Indo-pretreated rats decreased the surface hydrophobicity and induced bleeding of ileal loops in comparison with control bile, and both NSAID-induced changes were reversed if PC was added to the bile. Similarly, synthetic BS caused gastrointestinal bleeding, decreased ileal contact angles, and induced erythrocyte hemolysis, all of which were reversed by addition of equimolar PC. This protective role of PC in both the in vivo and in vitro systems was partially blocked by Indo, although the NSAID had no effect on these properties on its own.

CONCLUSIONS

These findings support the hypothesis that PC protects the intestinal mucosa against injurious actions of BS, possibly by forming less toxic mixed micelles. Indo and perhaps other NSAIDs that enter the bile may damage the mucosa, not by a direct action, but by competing for the available protective PC molecules.

Clinical and pathologic overlap in nonsteroidal anti-inflammatory drug-related small bowel diaphragm disease and the neuromuscular and vascular hamartoma of the small bowel

Diaphragm disease (DD) is a radiographically subtle cause of small bowel obstruction and is part of the spectrum of diseases associated with nonsteroidal anti-inflammatory drug injury. The neuromuscular and vascular hamartoma (NMVH) is a nonepithelial hamartomatous, submucosally based proliferation of mature submucosal elements capable of causing small bowel obstruction. The authors report two patients in whom the clinical setting and gross pathology are that of DD, but the histologic characterization is identical to that described for NMVH. It is probable that in some patients the two diseases overlap so that some patients readily fit the criteria for both entities.

Dual action of nitric oxide in pathogenesis of indomethacin-induced small intestinal ulceration in rats

We investigated the pathogenic role of nitric oxide (NO) in indomethacin-induced intestinal ulceration in rats. Nonfasting animals responded to a single administration of indomethacin (10 mg/kg, s.c.), resulting in multiple hemorrhagic lesions in the small intestine, mostly the jejunum and ileum. The damage was first observed 6 hr after indomethacin, the severity increasing progressively with time up to 24 hr later, accompanied with the gene expression of inducible NO synthase (iNOS) and the increase of nitrite and nitrate (NOx) contents in the mucosa. The ocurrence of damage was significantly prevented when iNOS induction was inhibited by dexamethasone given either once 0.5 hr before or twice 0.5 hr before and 6 hr after indomethacin. Likewise, aminoguanidine (a relatively selective iNOS inhibitor) reduced the severity of damage, irrespective whether given twice or as a single injection 6 hr after indomethacin. By contrast, the non-selective NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) exhibited a biphasic effect, depending on the time of administration; the pre-administration worsened the damage, while the later administration reduced the severity of these lesions, yet both responses occureed in a L-arginine-sensitive manner. Pre-administration of L-NAME, but not aminoguanidine, significantly decreased NOx production in the intestinal mucosa of normal rats, while the increase of NOx production following indomethacin was significantly suppressed by the later administration of aminoguanidine as well as L-NAME. These results suggest that NO exerts a dual action in the pathogenesis of indomethacin-induced intestinal ulceration; NO generated by cNOS is protective against indomethacin, by maintaining the integrity of intestinal mucosa, while NO derived by iNOS plays a key pathogenic role in the ulcerogenic process.

[An ileal ulcer and diaphragm-type colonic stenosis due to diclofenac]

Nonsteroidal anti-inflammatory drugs (NSAID) are used extensively in the general population. It's well known the adverse effects of NSAID over the upper gastrointestinal tract and small intestine. Enteric-coated and slow release preparations were created in order to prevent those effects. We describe a woman case who took diclofenac for many years and developed both ileal ulceration and diaphragm-like colonic structure. Lesions in lower gastrointestinal tract were infrequent but severe; the lesion were seen on colonoscopy but not on barium studies; the physiopathology of these lesions remains uncertain; and the most efficacy attitude is the suppression of diclofenac.

CT findings of isolated small bowel angioedema due to iodinated radiographic contrast medium reaction

We report three cases of small bowel angioedema that showed circumferential wall thickening of the small bowel loops during infusion of iodinated contrast media. Follow-up small bowel series or computed tomography confirmed the normalized small bowel loops. When significant wall thickening of the long segment of the small bowel during infusion of contrast media is seen, radiologists should consider the possibility of isolated small bowel angioedema in spite of its rarity.

Protective effects of a culture supernatant of Lactobacillus acidophilus and antioxidants on ileal ulcer formation in rats treated with a nonsteroidal antiinflammatory drug

Ileal ulcers and thiobarbituric acid (TBA)-reactive substances in the ileal mucosa were induced in rats treated with a nonsteroidal antiinflammatory drug, 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl)thiophene (BFMeT), at a dose of 1,000 mg/kg administered with tap water as drinking water. However, the formation of ileal ulcers and TBA-reactive substances in the ileal mucosa was repressed by giving the animals a culture supernatant of Lactobacillus acidophilus as drinking water. We measured the antioxidative activity of the culture supernatant and found that the supernatant inhibited the formation of t-butyl hydroperoxide-induced TBA-reactive substances in erythrocyte membrane ghosts. Therefore, the effects of various known antioxidative compounds on the ileal ulcer formation induced by BFMeT were investigated. While alpha-tocopherol, t-butyl-1,4-hydroxyanisole and allopurinol did not repress ulcer formation after BFMeT treatment, ascorbic acid, dimethyl sulfoxide, glutathione and beta-carotene significantly inhibited formation. Among these compounds, ascorbic acid was the most effective. Accumulation of TBA-reactive substances in the ileal mucosa after BFMeT treatment also decreased significantly in rats treated with ascorbic acid. In addition, the percentage of gram-negative rods in the ileal contents of rats treated with BFMeT and tap water was dramatically increased, but it was not increased in rats treated with BFMeT and these antioxidants. A positive correlation between the percentage of gram-negative rods and the number of ileal ulcers was also observed. These results suggest that lipid peroxidation mediated by oxygen radicals plays an important role in the induction of ileal ulcers by BFMeT in rats, and that lipopolysaccharide-activated neutrophils probably produce highly reactive hypochlorous acid and hydrogen peroxide, which are inactivated by ascorbic acid and glutathione, respectively.

Bacterial wall lipopolysaccharide as a cause of intussusception in mice

BACKGROUND

There is evidence that intussusception is associated with bacterial infection. It was hypothesized that a component of the bacterial wall may induce the intussusception. This study was intended to determine whether lipopolysaccharide from Escherichia coli or Salmonella can initiate intussusception in mice.

METHODS

Lipopolysaccharide was injected intraperitoneally in mice, and the animals were examined for the presence of intussusception from 2 to 192 hours after injection. Gastrointestinal transit was assessed by measuring the passage of charcoal in the small intestine. Transit index was defined as the ratio between the distance traveled by charcoal and the total length of the small intestine.

RESULTS

Intussusceptions were found in as much as 25.9% of lipopolysaccharide-injected animals, whereas in control animals, the incidence was zero. The threshold for the lipopolysaccharide effect was at 4 mg/kg and incidence reached a plateau at 8 mg/kg to 16 mg/kg. The incidence of intussusception peaked 6 hours after injection of lipopolysaccharide and declined to zero after 15 hours. To test the possibility that lipopolysaccharide induces intussusception by altering motility, its effect on transit index was measured. A dose of 12 mg/kg lipopolysaccharide reduced the transit index from 56.2+/-1.4% to 37.7+/-2.1% (p < 0.05). No microscopic histologic changes were found in the bowels with intussusception.

CONCLUSIONS

Intraperitoneal bacterial wall lipopolysaccharide causes intussusception in mice by disturbing gastrointestinal motility.

Intussusception in an infant with acute lymphoblastic leukemia: a case report and review of the literature

PURPOSE

An ileocecal intussusception developed in a 7-month-old infant with acute lymphoblastic leukemia (ALL) during induction therapy. Gastrointestinal complications, especially intussusception, are rare in children with ALL.

PATIENT AND METHODS

The history of a 7-month-old white boy with ALL in whom an ileocecal intussusception developed 1 week into induction chemotherapy was reviewed. In addition, a literature search was performed to determine the prevalence of this complication in children with acute leukemia.

RESULTS

On day 4 of induction chemotherapy for B-lineage ALL, the infant developed abdominal distension with hypoactive bowel sounds. After a barium enema and abdominal computed tomography scan, the symptoms were determined to be caused by an ileocecal intussusception. Chemotherapy was resumed 1 week after immediate surgical intervention (reduction of intussusception and resection of the "leading edge") with an uneventful post-operative recovery. Histopathologic examination of the resected edge revealed an intact mucosa with areas of necrosis in the submucosa. This was associated with a dense lymphoid infiltrate composed of mature lymphocytes and leukemic cells, edema, and focal necrosis. Despite a 1-week delay in chemotherapy, a complete remission was documented at day 32.

DISCUSSION

The prevalence of intussusception in children with ALL and its possible etiology are discussed. The pathologic changes, clinical manifestations, and treatment outcome are briefly mentioned.

Diaphragm-like strictures of the ileum associated with NSAID use: a rare complication

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely prescribed for many conditions including arthritis. A rare complication of their use is diaphragm-like strictures of the small and large intestines. A 65-year-old woman with a 12-year history of arthritis came to us with a 35-pound weight loss and anorexia. She had been taking piroxicam for 3 years. Evaluation including enteroclysis revealed multiple mid-ileal diaphragm-like strictures and proximal small bowel dilatation. The symptoms persisted despite discontinuance of the drug. Abdominal exploration with intraoperative enteroscopy revealed five ileal strictures within a short segment of bowel. Resection was done and completion enteroscopy showed no other strictures. The patient recovered uneventfully and had full resolution of the symptoms. We discuss the difficulties in diagnosis and management of this drug complication and briefly review the literature.

Culture supernatants of Lactobacillus acidophilus and Bifidobacterium adolescentis repress ileal ulcer formation in rats treated with a nonsteroidal antiinflammatory drug by suppressing unbalanced growth of aerobic bacteria and lipid peroxidation

A nonsteroidal antiinflammatory drug, 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl) thiophene (BFMeT), induced ileal ulcers in rats after oral administration, while no ulcers were observed after subcutaneous injection. The ileal ulcer formation in BFMeT-treated rats was examined to correlate the administration of cultures of Lactobacillus acidophilus or Bifidobacterium adolescentis with intestinal bacteria in the ileal contents and lipid peroxidation of the small intestinal mucosa. Ileal ulcers were observed in more than 85% of the rats treated with BFMeT at a dose of 1,000 mg/kg when they were given tap water as drinking water. The incidence of ulcer formation was repressed by giving culture supernatants of L. acidophilus or B. adolescentis as drinking water, but not by giving the cell suspension as drinking water. Gram staining of the ileal contents of normal rats revealed that 97% of the stained bacteria were gram-positive rods and only 1.5% were gram-negative rods. The percentage of gram-negative rods 72 hr after BFMeT administration was 49.8% and increased over 30-fold in BFMeT-treated rats. However, the percentage of gram-negative rods was 9.7 % or 16%, respectively, in rats taking culture supernatants of L acidophilus or B. adolescentis. In addition, thiobarbituric acid-reactive substances in the ileal mucosa increased significantly in the rats given tap water for 72 hr after BFMeT treatment, but not in rats given the culture supernatants of L. acidophilus or B. adolescentis. Since BFMeT induced an unbalanced intestinal microflora, the effect of antibiotic treatment on ulcer formation in rats was examined. The magnitude of the ulcer formation in the antibiotic-treated rats was, in decreasing order, metronidazole >none > kanamycin > a mixture (bacitracin, neomycin and streptomycin). These results suggest that the intestinal microflora plays an important role in ulcer formation and that a metabolite(s) of L. acidophilus and B. adolescentis inhibits ileal ulcer formation by repressing changes in the intestinal microflora and lipid peroxidation in BFMeT-treated rats.