Upregulation of ATG9b by propranolol promotes autophagic cell death of hepatic stellate cells to improve liver fibrosis.

Proranolol has long been recommended to prevent variceal bleeding in patients with cirrhosis. However, the mechanisms of propranolol in liver fibrosis have not yet been thoroughly elucidated. Autophagic cell death (ACD) of activated hepatic stellate cells (HSCs) is important in the alleviation of liver fibrosis. Our study aims to assess the mechanisms of propranolol regulating HSC ACD and liver fibrosis. ACD of HSCs was investigated using lentivirus transfection. The molecular mechanism was determined using a PCR profiler array. The role of autophagy-related protein 9b (ATG9b) in HSC ACD was detected using co-immunoprecipitation and co-localization of immunofluorescence. Changes in the signalling pathway were detected by the Phospho Explorer antibody microarray. Propranolol induces ACD and apoptosis in HSCs. ATG9b upregulation was detected in propranolol-treated HSCs. ATG9b upregulation promoted ACD of HSCs and alleviated liver fibrosis in vivo. ATG9b enhanced the P62 recruitment to ATG5-ATG12-LC3 compartments and increased the co-localization of P62 with ubiquitinated proteins. The PI3K/AKT/mTOR pathway is responsible for ATG9b-induced ACD in activated HSCs, whereas the p38/JNK pathway is involved in apoptosis. This study provides evidence for ATG9b as a new target gene and propranolol as an agent to alleviate liver fibrosis by regulating ACD of activated HSCs.

Design, synthesis and molecular docking of new pyrazole-thiazolidinones as potent anti-inflammatory and analgesic agents with TNF-α inhibitory activity.

A new set of derivatives bearing pyrazole-methylenehydrazono-thiazolidinone scaffold 4-23 was designed, synthesized and confirmed by different spectroscopic means and elemental analyses. In-vivo anti-inflammatory and ulcerogenic evaluation was performed for all the newly synthesized derivatives using indomethacin, celecoxib and diclofenac as standard drugs. The compounds 5, 10, 15, 17, 21, 22 appeared to be the most promising candidates producing rapid onset and long duration of anti-inflammatory activity as well as promising GIT safety profile. Furthermore, analgesic evaluation revealed that the compounds 5, 10, 15 and 22 produced potent and long acting analgesia accompanied with significant inhibition of the inflammatory cytokine TNF-α level in comparison with the standard drugs. Molecular docking study of the latter derivatives was also carried out to rationalize their binding affinities and their modes of interactions with the active site of TNF-α.

Rack1 maintains intestinal homeostasis by protecting the integrity of the epithelial barrier.

Previously, we generated mouse models of Rack1 deficiency to identify key functions for Rack1 in regulating growth of intestinal epithelia: suppressing crypt cell proliferation and regeneration, promoting differentiation and apoptosis, and repressing development of neoplasia. However, other than low body weight, we did not detect an overt phenotype in mice constitutively deleted of Rack1 in intestinal epithelia ( vil-Cre: Rack1fl/fl mice), presumably because Rack1 was deleted in <10% of the total surface area of the epithelia. To assess the effect of Rack1 loss throughout the entire intestinal epithelia, we generated another mouse model of Rack1 deficiency, vil-Cre-ERT2: Rack1fl/fl. Within 5-10 days of the initial tamoxifen treatment, the mice lost over 20% of their body weight, developed severe diarrhea that for some was bloody, became critically ill, and died, if not euthanized. Necropsies revealed mildly distended, fluid-, gas-, and sometimes blood-filled loops of small and large bowel, inguinal lymphadenopathy, and thrombocytosis. Rack1 was deleted in nearly 100% of the epithelia in both the small intestine and colon when assessed by immunofluorescent or immunoblot analyses. Rack1 expression in other tissues and organs was not different than in control mice, indicating tissue specificity of the recombination. Histopathology revealed a patchy, erosive, hemorrhagic, inflammatory enterocolitis with denuded, sloughed off surface epithelium, and crypt hyperplasia. These results suggest a protective function for Rack1 in maintaining the integrity of intestinal epithelia and for survival. NEW & NOTEWORTHY Our findings reveal a novel function for Rack1 in maintaining intestinal homeostasis by protecting the epithelial barrier. Rack1 loss results in a patchy, erosive, hemorrhagic, inflammatory enterocolitis, which resembles that of inflammatory bowel diseases (IBD) in humans. Understanding mechanisms that protect barrier function in normal intestine and how loss of that protection contributes to the pathogenesis of IBD could lead to improved therapies for these and other erosive diseases of the gastrointestinal tract.

Proton Pump Inhibitors in Cardiovascular Disease: Drug Interactions with Antiplatelet Drugs.

Aspirin and P2Y12 receptor antagonists are widely used across the spectrum of cardiovascular diseases. Upper gastrointestinal complications, including ulcer and bleeding, are relatively common during antiplatelet treatment and, therefore, concomitant proton pump inhibitor (PPI) treatment is often prescribed.PPIs provide gastroprotection by changing the intragastric milieu, essentially by raising intragastric pH. In recent years, it has been heavily discussed whether PPIs may reduce the cardiovascular protection by aspirin and, even more so, clopidogrel. Pharmacodynamic and pharmacokinetic studies suggested an interaction between PPIs and clopidogrel, and subsequent clinical studies were conducted to evaluate the clinical impact of this interaction. More recently, it was reported that PPIs may also attenuate the antiplatelet effect of aspirin. This may be clinically important, because a fixed combination of aspirin and a PPI (esomeprazole) has recently been approved and because aspirin is the most widely used drug in patients with cardiovascular disease. The antiplatelet effect of the new P2Y12 receptor antagonists, ticagrelor and prasugrel, seems less influenced by PPI co-treatment.Given the large number of patients treated with antithrombotic drugs and PPIs, even a minor reduction of platelet inhibition potentially carries considerable clinical impact. The present book chapter summarizes the evidence regarding the widespread use of platelet inhibitors and PPIs in combination. Moreover, it outlines current evidence supporting or opposing drug interactions between these drugs and discusses clinical implications.

Prevention of Barrier Disruption by Heme Oxygenase-1 in Intestinal Bleeding Model.

In this study we investigated the effect of free heme, the local level of which was increased by bleeding, on the intestinal barrier function, using human epithelial colorectal adenocarcinoma cells (Caco-2). Our results show that the addition of hemin to the culture medium markedly disrupted the barrier function, which was significantly improved by glutamine supplementation. Although hemin treatment caused the increased expression of heme oxygenase (HO)-1, the inhibition of HO activity resulted in the aggravation of hemin-induced barrier dysfunction. Up-regulation of HO-1 by pretreatment with a low concentration of hemin almost completely prevented hemin-induced barrier dysfunction. Taken together, these observations indicate that an abnormally high level of intracellular free heme causes barrier dysfunction, probably through the modulation of proteins forming tight junctions.

Angiopoietin-1 prevents severe bleeding complications induced by heparin-like drugs and fibroblast growth factor-2 in mice.

Critically ill children can develop bleeding complications when treated with heparin-like drugs. These events are usually attributed to the anticoagulant activity of these drugs. However, previous studies showed that fibroblast growth factor-2 (FGF-2), a heparin-binding growth factor released in the circulation of these patients, could precipitate intestinal hemorrhages in mice treated with the heparin-like drug pentosan polysulfate (PPS). Yet very little is known about how FGF-2 induces bleeding complications in combination with heparin-like drugs. Here, we examined the mechanisms by which circulating FGF-2 induces intestinal hemorrhages in mice treated with PPS. We used a well-characterized mouse model of intestinal hemorrhages induced by FGF-2 plus PPS. Adult FVB/N mice were infected with adenovirus carrying Lac-Z or a secreted form of recombinant human FGF-2, and injected with PPS, at doses that do not induce bleeding complications per se. Mice treated with FGF-2 in combination with PPS developed an intestinal inflammatory reaction that increased the permeability and disrupted the integrity of submucosal intestinal vessels. These changes, together with the anticoagulant activity of PPS, induced lethal hemorrhages. Moreover, a genetically modified form of the endothelial ligand angiopoietin-1 (Ang-1*), which has powerful antipermeability and anti-inflammatory activity, prevented the lethal bleeding complications without correcting the anticoagulant status of these mice. These findings define new mechanisms through which FGF-2 and Ang-1* modulate the outcome of intestinal bleeding complications induced by PPS in mice and may have wider clinical implications for critically ill children treated with heparin-like drugs.

Usefulness of immunohistochemical studies in diagnosing metachronous gallbladder and small intestinal metastases from lung cancer with gastrointestinal hemorrhage: a case report.

Isolated metachronous gastrointestinal metastases from advanced-stage lung cancer are rarely diagnosed on the basis of symptoms and resected. In this report, we present a case of resectable metachronous gallbladder and small intestinal metastases of lung cancer. An 86-year-old woman was treated for lung cancer with resection of the right inferior lobe. Five months after the surgery, she was re-admitted because of melena and anemia. Ultrasonography showed a gallbladder tumor with gastrointestinal hemorrhage, and laparoscopic-assisted cholecystectomy was subsequently performed. However, 2 months after this event, the patient presented again with melena and anemia and was diagnosed with a small intestinal tumor. Therefore, laparoscopic-assisted partial resection of the small intestine was performed. Immunohistochemical staining for thyroid transcription factor-1 and cytokeratin 7 confirmed that the two resected tumors were metachronous metastases of the primary lung cancer. The patient died of liver metastases 5 months after the last surgery. Our experience with this case suggests that surgical resection might not be curative but palliative for patients with isolated gallbladder and small intestinal metastases diagnosed on the basis of melena that is resistant to conservative treatment.

[Expression of plasminogen activator system components in the gastric mucosa in portal hypertensive gastropathy].

OBJECTIVE: to study the expression of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the gastric mucosal (GM) vascular endothelium and epithelial cells of patients with portal hypertensive gastropathy (PHG) and those with portal hypertension (PH) without signs of PHG as compared to a control group. MATERIAL AND METHODS: GM biopsy specimens from patients with PHG, those with PH without signs of PHG, and controls with the normal gastric mucosa were immunohistochemically examined. RESULTS: Comparison of the expression of uPA in the GM vascular endothelium and epithelial vessels revealed no significant differences in the patient groups. The level of PAI-1 in the GM vessels was statistically significantly higher in the control group than in the groups of patients with PHG and PH without PHG. PAI-1 expression in the GM epithelial cells was significantly more commonly absent in the PHG group than in the control group. An analysis of an uPA and PAI-1 expression ratio showed a statistically significant predominance of the expression of uPA over its inhibitor in the GM vascular endothelium of the patients with PHG and those with PH without PHG as compared to the controls. CONCLUSION: The predominance of uPA over PAI-1 in the GM vessels and epithelial cells can play a role in the development of GM bleeding.

Prognostic impact of gastrointestinal bleeding and expression of PTEN and Ki-67 on primary gastrointestinal stromal tumors.

BACKGROUND: Prognostic indicators for gastrointestinal stromal tumors (GISTs) are under investigation. The latest risk classification criteria may still have room for improvement. This study aims to investigate prognostic factors for primary GISTs from three aspects, including clinicopathological parameters, immunohistochemical (IHC) expression of PTEN, and Ki-67 labeling index (LI), and attempts to find valuable predictors for the malignancy potential of primary GISTs. METHODS: Tumor samples and clinicopathological data from 84 patients with primary GISTs after R0 resection were obtained. Immunohistochemical analysis was performed based on tissue microarray (TMA) to estimate expression of PTEN and Ki-67 in tumor cells. RESULTS: The cut-off point of Ki-67 LI was determined as 1%, using a receiver operator characteristic test with a sensitivity of 71.7% and a specificity of 64.5%. Univariate analysis demonstrated the following factors as poor prognostic indicators for relapse-free survival (RFS) against a median follow-up of 40.25 months: gastrointestinal (GI) bleeding (P = 0.009), non-gastric tumor location (P = 0.001), large tumor size (P = 0.022), high mitotic index (P < 0.001), high cellularity (P = 0.012), tumor rupture (P = 0.013), absent or low expression of PTEN (P = 0.036), and Ki-67 LI >1% (P = 0.043). Gastrointestinal bleeding (hazard ratio, 3.85; 95% confidence interval, 1.63 to 9.10; P = 0.002) was a negative independent risk predictor in multivariate analysis, in addition to tumor size (P = 0.023), and mitotic index (P = 0.002). In addition, GI bleeding showed a good ability to predict recurrence potential, when included in our re-modified risk stratification criteria. CONCLUSIONS: This study suggests that GI bleeding is an independent predictor of poor prognosis for RFS in primary GISTs. Expression of PTEN and Ki-67 are correlated with high risk potential and may predict early recurrence in univariate analysis.

Von Willebrand disease-associated angiodysplasia: a few answers, still many questions.

The association between angiodysplasia and von Willebrand disease (VWD) has been known for more than 40 years. Bleeding in the gastrointestinal tract associated with angiodysplasia worsens the clinical course of this inherited haemorrhagic disorder and management may become difficult and challenging. Angiodysplasia associated with acquired defects or dysfunctions of von Willebrand factor (VWF) has also been reported in a variety of conditions such as monoclonal gammopathies, Heyde syndrome and in carriers of ventricular assist devices. The most recent advances concerning the mechanistic, clinical and therapeutic aspects of VWD-associated angiodysplasia are summarized in this review, together with the limitations of our knowledge that warrant further research in the frame of international cooperation.

Prophylactic ranitidine treatment in critically ill children--a population pharmacokinetic study.

AIMS: To characterize the population pharmacokinetics of ranitidine in critically ill children and to determine the influence of various clinical and demographic factors on its disposition. METHODS: Data were collected prospectively from 78 paediatric patients (n = 248 plasma samples) who received oral or intravenous ranitidine for prophylaxis against stress ulcers, gastrointestinal bleeding or the treatment of gastro-oesophageal reflux. Plasma samples were analysed using high-performance liquid chromatography, and the data were subjected to population pharmacokinetic analysis using nonlinear mixed-effects modelling. RESULTS: A one-compartment model best described the plasma concentration profile, with an exponential structure for interindividual errors and a proportional structure for intra-individual error. After backward stepwise elimination, the final model showed a significant decrease in objective function value (-12.618; P < 0.001) compared with the weight-corrected base model. Final parameter estimates for the population were 32.1 l h(-1) for total clearance and 285 l for volume of distribution, both allometrically modelled for a 70 kg adult. Final estimates for absorption rate constant and bioavailability were 1.31 h(-1) and 27.5%, respectively. No significant relationship was found between age and weight-corrected ranitidine pharmacokinetic parameters in the final model, with the covariate for cardiac failure or surgery being shown to reduce clearance significantly by a factor of 0.46. CONCLUSIONS: Currently, ranitidine dose recommendations are based on children's weights. However, our findings suggest that a dosing scheme that takes into consideration both weight and cardiac failure/surgery would be more appropriate in order to avoid administration of higher or more frequent doses than necessary.

Gastroprotective effects of Corchorus olitorius leaf extract against ethanol-induced gastric mucosal hemorrhagic lesions in rats.

BACKGROUND AND AIM: Corchorus olitorius is a medicinal plant traditionally utilized as an antifertility, anti-convulsive, and purgative agent. This study aimed to evaluate the gastroprotective effect of an ethanolic extract of C. olitorius against ethanol-induced gastric ulcers in adult Sprague Dawley rats. METHODS: The rats were divided into seven groups according to their pretreatment: an untreated control group, an ulcer control group, a reference control group (20 mg/kg omeprazole), and four experimental groups (50, 100, 200, or 400 mg/kg of extract). Carboxymethyl cellulose was the vehicle for the agents. Prior to the induction of gastric ulcers with absolute ethanol, the rats in each group were pretreated orally. An hour later, the rats were sacrificed, and gastric tissues were collected to evaluate the ulcers and to measure enzymatic activity. The tissues were subjected to histological and immunohistochemical evaluations. RESULTS: Compared with the extensive mucosal damage in the ulcer control group, gross evaluation revealed a marked protection of the gastric mucosa in the experimental groups, with significantly preserved gastric wall mucus. In these groups, superoxide dismutase and malondialdehyde levels were significantly increased (P < 0.05) and reduced (P < 0.05), respectively. In addition to the histologic analyses (HE and periodic acid-Schiff staining), immunohistochemistry confirmed the protection through the upregulation of Hsp70 and the downregulation of Bax proteins. The gastroprotection of the experimental groups was comparable to that of the reference control medicine omeprazole. CONCLUSIONS: Our study reports the gastroprotective property of an ethanolic extract of C. olitorius against ethanol-induced gastric mucosal hemorrhagic lesions in rats.

Pharmacogenomics of acetylsalicylic acid and other nonsteroidal anti-inflammatory agents: clinical implications.

PURPOSE: Pharmacogenomics investigates interindividual genetic variability in the DNA sequence of drug targets, drug-metabolizing enzymes or disease genes, RNA expression, or protein translation of genes affecting drug response and drug safety. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly prescribed medications with well-documented variation in patient response in terms of efficacy and safety. This variation may in part be explained by pharmacogenomics. METHODS: In this paper I review data on the pharmacogenomics of aspirin and other NSAIDs focusing on clinical implications. RESULTS: Existing scientific evidence supports the pharmacogenomic basis of interindividual variation in treatment response to aspirin and NSAIDs, with clinical implications for antiplatelet action, cancer chemoprevention, and drug safety. However, further research efforts are needed before knowledge on the pharmacogenomics of aspirin and NSAIDs can be implemented in clinical practice. CONCLUSION: The outcome of these research efforts would be anticipated to have added value for both science and society, contributing to the enhanced efficacy and safety of these agents through patient selection.

Neither inhalative nor intravenous application of carbon monoxide modifies gastric mucosal oxygenation.

This study was designed to compare the effects of different ways of administering carbon monoxide (intravenous and inhalative) on gastric mucosal oxygenation in a canine model of hemorrhage. Six chronically instrumented dogs were repeatedly anesthetized and randomized to each of the following protocols: In a first series the animals were ventilated either with 100 ppm carbon monoxide (CO) or without followed by hemorrhage and re-transfusion. In a second series a saturated CO solution was infused, compared to normal saline, again followed by hemorrhage and re-transfusion. In a control series, animals received either CO-saline or saline without any further intervention. Microvascular oxygenation of the gastric mucosa (µHbO2) was assessed continuously by tissue reflectance spectrophotometry. Cardiac output was measured intermittently and oxygen delivery (DO2) was calculated. The application of CO, inhalative and intravenous, increased carboxyhemoglobin levels without effect on µHbO2. Hemorrhage reduced µHbO2 in all groups, paralleled by a reduction in DO2 without any differences between groups related to the application of CO. Neither intravenous nor inhalative application of CO alters µHbO2 during physiological conditions or during hemorrhage. Thus, independent of the application way, low dose CO does not seem to modulate regional mucosal oxygenation in cytoprotective concentrations.

[Gastric secretory function in patients with chronic renal insufficiency and gastroduodenal hemorrhage].

Gastric hypersecretion occurrence in patients, suffering chronic renal insufficiency (CHRI), creates conditions for acido-peptic gastroduodenal zone affection with possible formation of erosive-ulcerative defects, complicated by hemorrhage. In 116 patients, suffering CHRI, the state of gastric mucosa secretory function was studied up. In patients with an acute gastrointestinal hemorrhage and CHRI in conservative and terminal stages the analysis of acidity was conducted.

Citrobacter rodentium Lysogenized with a Shiga Toxin-Producing Phage: A Murine Model for Shiga Toxin-Producing E. coli Infection.

Shiga toxin-producing E. coli (STEC) is a common foodborne pathogen in developed countries. STEC generates "attaching and effacing" (AE) lesions on colonic epithelium, characterized by effacement of microvilli and the formation of actin "pedestals" beneath intimately attached bacteria. In addition, STEC are lysogenized with a phage that, upon induction, can produce potent Shiga toxins (Stx), potentially leading to both hemorrhagic colitis and hemolytic uremic syndrome. Investigation of the pathogenesis of this disease has been challenging because STEC does not readily colonize conventional mice.Citrobacter rodentium (CR) is a related mouse pathogen that also generates AE lesions. Whereas CR does not produce Stx, a murine model for STEC utilizes CR lysogenized with an E. coli-derived Stx phage, generating CR(Φstx), which both colonizes conventional mice and readily gives rise to systemic disease. We present here key methods for the use of CR(Φstx) infection as a highly predictable murine model for infection and disease by STEC. Importantly, we detail CR(Φstx) inoculation by feeding, determination of pathogen colonization, production of phage and toxin, and assessment of intestinal and renal pathology. These methods provide a framework for studying STEC-mediated systemic disease that may aid in the development of efficacious therapeutics.

Role of melatonin in mucosal gastroprotection against aspirin-induced gastric lesions in humans.

Melatonin and its precursor, l-tryptophan, have been shown to exert gastroprotective effects in animals, but their influence on the gastric damage by aspirin (ASA) in humans has been sparingly investigated. In this study, we designed to determine the effects of melatonin and l-tryptophan on ASA-induced gastric mucosal damage, gastric microbleeding, mucosal generation of prostaglandin E(2), and plasma melatonin, and gastrin levels. Three groups of healthy male volunteers (n = 30) with intact gastric mucosa received daily for 11 days either ASA alone or that combined with melatonin or tryptophan. Gastric blood loss and mucosal damage were evaluated at 3rd, 7th, and 11th days of ASA administration by endoscopy using Lanza score. ASA alone caused a marked rise of gastric damage and gastric blood loss, mainly at day 3rd and 7th, but they were significantly reduced at 11th day. Pretreatment with melatonin or tryptophan remarkably reduced ASA induced gastric lesions and microbleeding. Gastric mucosal generation of PGE(2) was suppressed by about 90% in all subjects treated with ASA alone without or with addition of melatonin or tryptophan. Plasma melatonin was markedly increased after treatment with melatonin or tryptophan plus ASA, but it was also raised significantly after application of ASA alone. Plasma gastrin levels were raised in subjects given melatonin or tryptophan plus ASA, but not in those with ASA alone. We conclude that melatonin and its precursor tryptophan given orally significantly reduce gastric lesions induced by ASA possibly due to (a) direct gastroprotective action of exogenous melatonin or that generated from tryptophan and (b) gastrin released from the gastric mucosa by melatonin or tryptophan.

A bicarbonate-alkaline mineral water protects from ethanol-induced hemorrhagic gastric lesions in mice.

Ingestion of elevated amounts of ethanol in humans and rodents induces hemorrhagic gastric lesions, at least in part by increasing oxidative stress. The present study was undertaken in order to evaluate the influence of a bicarbonate-alkaline mineral water (Uliveto on ethanol-induced hemorrhagic gastric lesions in mice. Lesions were evaluated by both macroscopic and microscopic analysis. In a first set of experiments, mice were allowed to drink Uliveto or reference water ad libitum until 3 h prior to intragastric (i.g.) ethanol (23 ml/kg) administration. Neither Uliveto nor reference water did afford any protection. In a second set of experiments, acute exposure to reference water (35 ml/kg, i.g.), given 30 min before ethanol, did not inhibit gastric lesions. However, administration of the same amount of Uliveto caused a remarkable reduction in ethanol-evoked gastric lesions. Ethanol administration increased 4-hydroxy-2-nonenal levels, a byproduct of oxidative stress, in the luminal part of the gastric mucosa. This response was substantially reduced by about 70% by Uliveto, but not by reference water. Reference water, added with the bicarbonate content, present in the Uliveto water, protected against ethanol-induced lesions. Thus, acute pre-exposure to bicarbonate-alkaline mineral water (Uliveto) protects from both oxidative stress and hemorrhagic gastric lesions caused by ethanol. The elevated bicarbonate content of Uliveto likely accounts for the protection against ethanol-induced gastric injury.

Faecal calprotectin and ultrasonography as non-invasive screening tools for detecting colorectal polyps in children with sporadic rectal bleeding: a prospective study.

BACKGROUND: Colorectal polyps are reported in 6,1% of paediatric colonoscopies and in 12% of those performed for lower gastrointestinal bleeding. Although colonoscopy is widely used in paediatric patients, it requires bowel preparation and general anaesthesia or deep sedation, and in rare cases, it can cause complications. Non-invasive screening techniques able to predict polyps in children with isolated and sporadic rectal bleeding may play a key role in the selection of patients needing colonoscopy. METHODS: We enrolled all children undergoing colonoscopy for isolated and sporadic rectal bleeding to determine the diagnostic accuracy of faecal calprotectin, ultrasonography (US) and digital rectal examination as diagnostic methods for screening colorectal polyps. RESULTS: A total of 26 of 59 enrolled patients (44.1%) had colonic polyps, one patient had multiple polyps, and 23% of children had polyps proximal to the splenic flexure. The diagnostic accuracy of faecal calprotectin for detecting colorectal polyps was 96.6%, with a sensitivity of 100%. False-positive faecal calprotectin was shown in 2 patients with non-steroidal anti-inflammatory drug-related lesions. The diagnostic accuracy of ultrasound was 77.9%. Polyps not seen with ultrasound tended to be relatively smaller (1.5 vs 2.3, p = 0.001) and located in the rectum. The combined use of FC, US and digital rectal examination obtained a specificity and PPV of 100%. CONCLUSIONS: FC combined with US and digital rectal examination is a good and promising non-invasive screening test for detecting colorectal polyps in children with isolated and sporadic rectal bleeding.

Gastrointestinal safety of nonsteroidal antiinflammatory drugs and selective cyclooxygenase-2 inhibitors in patients on warfarin.

BACKGROUND: The interaction between warfarin and nonsteroidal antiinflammatory drugs (NSAIDs) is well known. However, warfarin and NSAIDs are still commonly prescribed together. Selective cyclooxygenase-2 (COX-2) inhibitors, a newer class of NSAID, offer potential advantages over the nonselective NSAIDs in patients treated with warfarin. OBJECTIVE: To study the rates of hospitalization for gastrointestinal (GI) bleeding events in 3 groups of patients: those taking warfarin only, those taking warfarin plus a nonselective NSAID, and those taking warfarin plus a selective COX-2 inhibitor. METHODS: This was a retrospective cohort analysis in a large nonprofit health maintenance organization. All warfarin users from January 1, 2000, to December 31, 2005, were eligible for inclusion in the study. Eligible patients were grouped by their exposure time to warfarin only, warfarin plus nonselective NSAIDs, or warfarin plus selective COX-2 inhibitor. The study endpoint was hospitalization for a GI bleed. Patients were matched using a propensity scoring methodology. A multivariate Cox proportional hazards model was used to estimate the hazard ratio for GI bleeding between patient cohorts, controlling for age, sex, baseline medical conditions, prior history of GI bleeding, and prescription drug use. RESULTS: The eligible population consisted of 35,548 patients undergoing 46,214 courses of warfarin therapy. The adjusted hazard ratio for hospital-associated GI bleeding in the warfarin plus nonselective NSAID group versus warfarin alone was 3.58 (95% CI 2.31 to 5.55; p < 0.01) and for warfarin plus selective COX-2 inhibitor versus warfarin alone was 1.71 (95% CI 0.60 to 4.84; p = 0.31). For nonselective NSAIDs plus warfarin versus selective COX-2 inhibitor plus warfarin, the adjusted hazard ratio was 3.69 (95% CI 1.42 to 9.60; p = 0.01). CONCLUSIONS: In general, nonselective NSAIDs and selective COX-2 inhibitors should be avoided in patients taking warfarin. In situations where patients require NSAIDs and cannot be managed using other therapies, our results suggest that selective COX-2 inhibitors are associated with fewer hospitalizations for GI bleeding.