Autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a rare, heterogeneous, fibroinflammatory disorder of the pancreas. It has gained increasing recognition due to a presentation that can mimic difficult-to-treat disorders such as pancreatic cancer, cholangiocarcinoma and primary sclerosing cholangitis. In contrast, autoimmune pancreatitis is a benign disease that is very responsive to therapy with corticosteroids. There are two types of AIP. Type 1 disease is the most common worldwide and is associated with extrapancreatic manifestations and elevated levels of IgG4-positive cells. Type 2 AIP is characterized by a paucity of IgG4-positive cells and is more difficult to diagnose. This review provides an update on the diagnosis, pathophysiology and treatment of AIP, with special emphasis on the two subtypes.

Systematic review: the quality of the scientific evidence and conflicts of interest in international inflammatory bowel disease practice guidelines

BACKGROUND

Guidelines published by the international gastroenterology societies establish standards of care and seek to improve patient outcomes.

AIM

We examined inflammatory bowel disease guidelines (IBD) for quality of evidence, methods of grading evidence and conflicts of interest (COI).

METHODS

All 182 guidelines published by the American College of Gastroenterology, American Gastroenterological Association, British Society of Gastroenterology, Canadian Association of Gastroenterology, Crohn's and Colitis Foundation of America and European Crohn's and Colitis Organisation as of 27 September 2012 were reviewed. Nineteen IBD guidelines were found.

RESULTS

Eighty-nine per cent (n = 17/19) of the guidelines graded the levels of evidence using seven different systems. Of the 1070 recommendations reviewed, 23% (n = 249) cited level A evidence; 28% (n = 302) level B; 36% (n = 383) level C and 13% (n = 136) level D. The mean age of the guidelines was 4.2 years. In addition, 61% (n = 11/19) of the guidelines failed to comment on COI. All eight articles commenting on COI had conflicts with 81% (n = 92/113) of authors reported an average 11.7 COI. Lastly, there were variations in the recommendations between societies.

CONCLUSIONS

Nearly half the IBD guideline recommendations are based on expert opinion or no evidence. Majority of the guidelines fail to disclose any COI, and when commenting, all have numerous COI. Furthermore, the guidelines are not updated frequently and there is a lack of consensus between societal guidelines. This study highlights the critical need to centralize and redesign the guidelines development process.

The Crohn's disease activity index (CDAI) is similarly elevated in patients with Crohn's disease and in patients with irritable bowel syndrome

BACKGROUND

While the Crohn's disease activity index (CDAI) is the gold standard for defining clinical endpoints in Crohn's disease (Crohn's) clinical trials, its ability to distinguish symptoms due to inflammation from those that are non-inflammatory has been questioned.

AIM

To compare CDAI scores in patients with Crohn's and those with Irritable Bowel Syndrome (IBS).

METHODS

This was a prospective, cross-sectional cohort study of 91 patients with either Crohn's (n = 44) or IBS (n = 47). Total CDAI and individual component scores were recorded and comparisons were made between Crohn's and IBS patients.

RESULTS

Mean CDAI scores were higher in the IBS patients (183 vs. 157, P = 0.1). Sixty-two per cent (n = 29) of IBS patients had CDAI scores greater than 150. Mean CDAI haematocrit score (35.9 vs. 23.0, P = 0.02) and CRP level (6.8 vs. 2.0, P = 0.002) were higher in the Crohn's group. Analysis of CDAI sub-scores demonstrated that IBS patients had significantly higher pain (mean 1.7 vs. 0.8, P = 0.0007) and well-being scores (mean 1.2 vs. 0.8, P = 0.04) relative to patients with Crohn's. Specifically evaluating patients with CDAI greater than 150 (n = 51), IBS patients had higher pain sub-scores (mean 2.4 vs. 1.4, P = 0.002), whereas patients with Crohn's had higher CRP (mean 8.4 vs. 1.8, P = 0.001).

CONCLUSIONS

Our study demonstrates that the CDAI does not discriminate patients with symptoms due to active Crohn's from patients with IBS. Patients with IBS can have CDAI scores in the clinically meaningful range. Objective measures, such as CDAI haematocrit score and CRP, are more specific markers of inflammation.

Adenoma detection rates vary minimally with time of day and case rank: a prospective study of 2139 first screening colonoscopies

BACKGROUND

Adenoma detection rate is an important measure of colonoscopy quality; however, factors including procedure order that contribute to adenoma detection are incompletely understood.

OBJECTIVE

The aim of this study was to prospectively evaluate factors associated with adenoma detection rate.

DESIGN

Prospective cohort study. Data were collected on patient and physician characteristics, trainee participation, time of day, and case rank.

SETTING

Outpatient tertiary-care center.

PATIENTS

This study involved consecutive patients presenting for first screening colonoscopies.

MAIN OUTCOME MEASUREMENTS

Adenoma and polyp detection rates (proportion of cases with one or more lesion detected) and ratios (mean number of lesions detected per case).

RESULTS

A total of 2139 colonoscopies were performed by 32 gastroenterologists. Detection rates were 42.7% for all polyps, 25.4% for adenomas, and 5.0% for advanced adenomas. Adenoma detection was associated with male sex and increasing age on multivariate analysis. In the overall study cohort, time of day and case rank were not significantly associated with detection rates. In post hoc analysis, polyp and adenoma detection rates appeared lower after the fifth case of the day for endoscopists with low volumes of cases and after the tenth case of the day for endoscopists with high volumes of cases.

LIMITATION

Single center.

CONCLUSION

Overall, time of day and case rank did not influence adenoma detection rate. We observed a small but significant decrease in detection rates in later procedures, which was dependent on physician typical procedure volume. These findings imply that colonoscopy quality in general is stable throughout the day; however, there may be a novel "stamina effect" for some endoscopists, and interventions aimed at improving colonoscopy quality need to take individual physician practice styles into consideration.

The safety and efficacy of oral docosahexaenoic acid supplementation for the treatment of primary sclerosing cholangitis - a pilot study

BACKGROUND

Primary sclerosing cholangitis (PSC) is characterised by progressive inflammatory and fibrotic destruction of the biliary ducts. There are no effective medical therapies and presently high dose ursodeoxycholic acid is no longer recommended due to significant adverse events in a recent clinical trial. Cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction is associated with PSC in both children and adults. Since CFTR dysfunction leads to altered fatty acid metabolism, specifically reduced docosahexaenoic acid (DHA), we hypothesised that DHA supplementation might be an effective therapy for patients with PSC.

AIM

To determine the safety and efficacy of oral DHA supplementation for the treatment of PSC.

METHODS

We conducted a 12 month open-label pilot study to evaluate safety of oral DHA and its effects on serum alkaline phosphatase as a primary outcome measure in 23 patients with PSC. DHA was administered orally at 800 mg twice per day. Secondary outcomes included changes in other liver function tests and fibrosis biomarkers.

RESULTS

A 1.7-fold increase in serum DHA levels was observed with supplementation. The mean alkaline phosphatase level (±S.E.) at baseline was 357.8 ± 37.1 IU compared to 297.1 ± 23.7 IU (P < 0.05) after 12 months of treatment. There were no changes in other liver function tests and fibrosis biomarkers. No adverse events were reported.

CONCLUSIONS

Oral DHA supplementation is associated with an increase in serum DHA levels and a significant decline in alkaline phosphatase levels in patients with PSC. These data support the need for a rigorous trial of DHA therapy in PSC.

The incidence and clinical spectrum of refractory celiac disease in a north american referral center

OBJECTIVES

Refractory celiac disease (RCD) is one of the most serious causes of persistent symptoms in patients with celiac disease (CD). Published reports suggest that approximately half of patients in Europe are RCD type II, which carries a poor prognosis with a 5-year survival rate of ~50% compared with ~90% for RCD type I. However, disease patterns may be different in North America. The aim of this study was to explore the clinical spectrum of RCD in a North American population.

METHODS

Medical records of patients with biopsy-proven CD presenting to our institution were reviewed for a diagnosis of RCD. Demographic data, clinical characteristics, and mortality were evaluated and compared with our general CD population.

RESULTS

In all, 34 out of 844 (4.0%) CD patients had RCD. The cumulative incidence of RCD for patients diagnosed with CD at our center was 1.5%. Unintentional weight loss at diagnosis of RCD was found in 76.5% (n=26) compared with 16.7% (n=141) at diagnosis of CD (P<0.0001) and diarrhea at diagnosis of RCD was found in 79.4% (n=27) compared with 40.5% (342) at diagnosis of CD (P<0.0001). Five patients (14.7%) were diagnosed with RCD type II and of these, two died of enteropathy-associated lymphoma within 24 months of diagnosis of CD (observed mortality rate 5.9%).

CONCLUSIONS

Although RCD is a serious condition with significant morbidity; the observed mortality rates are low in our population. This study suggests that RCD may be less severe in North American vs. European populations.

Small intestinal release mesalamine for the treatment of refractory celiac disease type I

GOAL

The goal of this study is to evaluate the safety and efficacy of Small intestinal release mesalamine (SIRM) for symptom relief in refractory celiac disease (RCD).

BACKGROUND

Therapeutic options for the RCD are inadequate and treatment with corticosteroids and immunosuppressants is limited by side effects. SIRM has been shown to have local antiinflammatory action and excellent tolerability.

STUDY

We reviewed records of the RCD patients who received SIRM in an open-label therapeutic trial. Data included demographics, disease characteristics, dose and duration of SIRM therapy, and response. Response was categorized as complete if there was complete resolution of symptoms, partial if there was at least 50% improvement, and nonresponsive if there was less than 50% improvement.

RESULTS

Four patients were treated with SIRM alone and 6 received SIRM and oral budesonide. Within 4 weeks, 50% had complete response and an additional 10% had partial response. Two of the 6 patients were able to discontinue budesonide. One patient discontinued SIRM owing to headaches.

CONCLUSION

SIRM seems to be a safe and efficacious treatment option in patients with RCD. Larger, controlled trials of this agent are warranted.

Celiac crisis is a rare but serious complication of celiac disease in adults

BACKGROUND & AIMS

Celiac crisis is a life-threatening syndrome in which patients with celiac disease have profuse diarrhea and severe metabolic disturbances. Celiac crisis is rare among adults and not well documented. To improve awareness of this condition and to facilitate diagnosis, we reviewed cases of celiac crisis to identify presenting features, formulate diagnostic criteria, and develop treatment strategies.

METHODS

Cases of biopsy-proven celiac disease were reviewed. Celiac crisis was defined as acute onset or rapid progression of gastrointestinal symptoms that could be attributed to celiac disease and required hospitalization and/or parenteral nutrition, along with signs or symptoms of dehydration or malnutrition.

RESULTS

Twelve patients met preset criteria for celiac crisis; 11 developed celiac crisis before they were diagnosed with celiac disease. Eleven patients had increased titres of transglutaminase antibodies and 1 had immunoglobulin A deficiency. Results of biopsy analyses of duodenum samples from all patients were consistent with a Marsh 3 score (33% with total villous atrophy). Patients presented with severe dehydration, renal dysfunction, and electrolyte disturbances. All patients required hospitalization and intravenous fluids, 6 required corticosteroids, and 5 required parenteral nutrition. All patients eventually had a full response to a gluten-free diet.

CONCLUSIONS

Celiac crisis has a high morbidity and, although rarely described, occurs in adults and often has a clear precipitating factor. Patients who present with severe unexplained diarrhea and malabsorption should be tested for celiac disease; treatment with systemic steroids or oral budesonide should be considered. Nutritional support often is required in the short term but most patients ultimately respond to gluten avoidance.

ERCP in the very elderly: outcomes among patients older than eighty

Life expectancy is rising, which is increasing the demand for endoscopic retrograde cholangiopancreatography (ERCP) in the elderly. Little data, particularly on complex procedures, has been reported. In this study, we compare the differences in the success and complications in ERCP between patients older and younger than 80 years old. We used a large endoscopic database reviewing the ERCPs performed and 30-day complications addressing age, degree of difficulty of procedures, and complications. A total of 2,606 patients underwent 3,924 ERCPs. Six hundred and twenty-eight were octogenarians undergoing 728 procedures. Mean age was 83.5 years in the octogenarian group and 59.0 years in the younger group. The endoscopic success rate was lower in octogenarians (96.9 vs. 98.3%, P = 0.004). Overall, complication rates between both groups was significantly less in older compared to younger patients (1.64 vs. 3.50%, P = 0.006). Complication and failure rates were higher as procedure complexity increased in all patients. ERCP in the elderly carries a high degree of success with low complication rates. Elderly patients carry similar risks of bleeding and perforation and a lower risk of pancreatitis.

Treatment of Helicobacter pylori infection with intra-gastric violet light phototherapy: a pilot clinical trial

BACKGROUND AND OBJECTIVE

Helicobacter pylori infects the mucus layer of the human stomach and causes peptic ulcers and adenocarcinoma. We have previously shown that H. pylori accumulates photoactive porphyrins making the organism susceptible to inactivation by light, and that small spot endoscopic illumination with violet light reduced bacterial load in human stomachs. This study assessed the feasibility and safety of whole-stomach intra-gastric violet phototherapy for the treatment of H. pylori infection.

STUDY DESIGN/MATERIALS AND METHODS

A controlled, prospective pilot trial was conducted using a novel light source consisting of laser diodes and diffusing fibers to deliver 408-nm illumination at escalating total fluences to the whole stomach. Eighteen adults (10 female) with H. pylori infection were treated at three U.S. academic endoscopy centers. Quantitative bacterial counts were obtained from biopsies taken from the antrum, body, and fundus, and serial urea breath tests.

RESULTS

The largest reduction in bacterial load was in the antrum (>97%), followed by body (>95%) and fundus (>86%). There was a correlation between log reduction and initial bacterial load in the antrum. There was no dose-response seen with increasing illumination times. The urea breath test results indicated that the bacteria repopulated in days following illumination.

CONCLUSION

Intra-gastric violet light phototherapy is feasible and safe and may represent a novel approach to eradication of H. pylori, particularly in patients who have failed standard antibiotic treatment. This was a pilot study involving a small number of patients. Further research is needed to determine if phototherapy can be effective for eradicating H. pylori.

Interaction between psychiatric and autoimmune disorders in coeliac disease patients in the Northeastern United States

BACKGROUND

Previous studies yielded conflicting results regarding the presence of an association between coeliac disease (CD) and psychiatric disorders including depression. This association has not been studied in the United States.

AIM

To determine the prevalence of psychiatric and autoimmune disorders in patients with CD in the US compared with control groups.

METHODS

In a case control study, the prevalence of psychiatric and autoimmune disorders was compared in 600 CD patients, 200 irritable bowel syndrome (IBS) patients and 200 healthy controls.

RESULTS

The prevalence of depression in CD was 17.2% and was similar to that in IBS (18.5%, P = 0.74) and controls (16.0%, P = 0.79). Among CD patients, type I diabetes mellitus (DM) was identified as a significant risk factor for depression (P < 0.01) with 37% of patients with both CD and type I DM having clinical depression.

CONCLUSION

The prevalence of depression in CD is similar to that in other chronic gastrointestinal diseases and healthy controls. However, there is a markedly elevated risk of depression in patients with both type I DM and CD. Differing rates of type 1 DM among coeliac populations may account for disparity in published rates of depression in patients with CD.

Heightened NTPDase-1/CD39 expression and angiogenesis in radiation proctitis

Radiation proctitis is an inflammatory process associated with persistent and refractory lower gastrointestinal bleeding. Purinergic signaling regulates hemostasis, inflammation, and angiogenesis. For example, CD39, the vascular ectonucleotidase, blocks platelet activation and is required for angiogenesis. Whether CD39 expression is affected by radiation injury is unknown. The aim of this work was to study CD39 expression patterns after clinical radiation injury to the rectum. We prospectively enrolled eight patients with radiation proctitis and five gender-matched controls. Biopsies were taken from normal-appearing rectal mucosa of controls and from the normal sigmoid and abnormal rectum of patients. Expression patterns of CD39, P2Y2 receptor, CD31, CD61 integrin, and vascular endothelial growth factor receptor 2 were examined by immunostaining; levels of CD39 were further evaluated by Western blots. Chronic inflammatory lesions of radiation proctitis were associated with heightened levels of angiogenesis. Immunohistochemical stains showed increased vascular expression of CD39, as confirmed by Western blots. CD39 was co-localized with vascular endothelial markers CD31 and CD61 integrin, as well as expressed by stromal tissues. Development of neovasculature and associated CD39 expression in radiation proctitis may be associated with the chronic, refractory bleeding observed in this condition.

Helicobacter pylori infection stimulates plasminogen activator inhibitor 1 production by gastric epithelial cells

Chronic infection with the gastric pathogen Helicobacter pylori significantly increases the risk of developing atrophic gastritis, peptic ulcer disease, and gastric adenocarcinoma. H. pylori strains that possess the cag pathogenicity island, which translocates CagA into the host cells, augment these risks. The aim of this study was to determine the molecular mechanisms through which H. pylori upregulates the expression of plasminogen activator inhibitor 1 (PAI-1), a member of the urokinase activator system that is involved in tumor metastasis and angiogenesis. Levels of PAI-1 mRNA and protein were examined in tissues from H. pylori-infected patients and in vitro using AGS gastric epithelial cells. In vitro, cells were infected with toxigenic cag-positive or nontoxigenic cag-negative strains of H. pylori or isogenic mutants. The amount of PAI-1 secretion was measured by enzyme-linked immunosorbent assay, and mRNA levels were determined using real-time PCR. The regulation of PAI-1 was examined using the extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor and small interfering RNA. Analysis of human biopsy samples revealed an increase in both PAI-1 mRNA and protein levels in patients with H. pylori gastritis compared to those of uninfected controls. Infection of AGS cells with H. pylori significantly increased PAI-1 mRNA expression and the secretion of PAI-1 protein. Moreover, PAI-1 mRNA and protein production was more pronounced when AGS cells were infected by H. pylori strains carrying a functional cag secretion system than when cells were infected by strains lacking this system. PAI-1 secretion was also reduced when cells were infected with either cagE-negative or cagA-negative mutants. The ectopic overexpression of CagA significantly increased the levels of PAI-1 mRNA and protein, whereas blockade of the ERK1/2 pathway inhibited H. pylori-mediated PAI-1 upregulation. These findings suggest that the upregulation of PAI-1 in H. pylori-infected gastric epithelial cells may contribute to the carcinogenic process.

Quantifying gastric Helicobacter pylori infection: a comparison of quantitative culture, urease breath testing, and histology

Although there are several methods to detect Helicobacter pylori infection, there is no simple validated test to quantify the density of infection, which is believed to play a major role in the pathogenesis of H. pylori-associated gastritis and peptic ulceration. The aim of this study was to evaluate and compare noninvasive and invasive tests for assessing the level of H. pylori infection so as to facilitate the development and clinical testing of new antibiotic treatments. Healthy volunteers (n=323) were screened for H. pylori infection by serology and, if positive (n=86), invited to undergo (13)C urea breath testing (UBT) (n=55). An increase of >2.4 parts per thousand (13)CO(2) at 15 min compared to baseline was considered a positive test. Total cumulative urease activity (mumol) at 60 min was also calculated. UBT-positive subjects underwent endoscopy and nine biopsies were obtained from defined sites for quantitative culture and histological grading using the modified Sydney System. A total of 19 subjects were studied, 4 of whom underwent repeat testing. All subjects were positive for H. pylori by serology, UBT, culture, and histology. The increase in (13)CO(2) at 30 min correlated with the total cumulative urease activity at 60 min (r (2)=0.92, P< 0.0001). Bacterial counts (log cfu/biopsy; mean+/-SD) were 3.9+/-0.5, 3.9+/-0.4, and 3.9+/-0.6 at the lesser curve antrum, greater curve antrum, and corpus, respectively. There was no significant correlation between UBT results and bacterial counts at any biopsy site. Nor was there any significant correlation between the histology grading and either the UBT or the bacterial counts at any site. This study indicates that there is little correlation among the three methods used to measure bacterial burden in H. pylori infection. Thus, decrements in bacterial numbers during single-agent therapy cannot be measured reliably by UBT and therefore cannot be used to evaluate the potential efficacy of novel agents to treat gastric H. pylori infection.

Cyclooxygenase-2 expression in hepatocellular carcinoma, cirrhosis and chronic hepatitis in the United States

Aberrant expression of cyclooxygenase-2 in hepatocellular carcinoma was described in Asia. Using immunohistochemistry, we studied the expression of cyclooxygenase-2 in hepatocellular carcinoma, chronic hepatitis, and cirrhosis in a US institution. A staining score of 0-5 representing the sum of an intensity score and a distribution score was used. The mean scores were 2.2+/-1.60 for chronic hepatitis, 4.37+/-1.15 for cirrhosis, and 4.76+/-0.54 for hepatocellular carcinoma. We found a significant difference in mean staining scores between chronic hepatitis and cirrhosis (p < 0.0001), as well as between chronic hepatitis and hepatocellular carcinoma (p < 0.0001). Fibrosis correlated with cyclooxygenase-2 staining score (r=0.65).

IN CONCLUSION

(1) Cyclooxygenase-2 expression is higher in cirrhosis and hepatocellular carcinoma when compared to chronic hepatitis. (2) Cyclooxygenase-2 expression correlates with the stage of fibrosis. (3) These results imply that in chronic hepatitis and possibly in cirrhosis, hepatocarcinogenesis may be a cyclooxygenase-2 dependent mechanism.

Induction of colitis in cftr-/- mice results in bile duct injury

It is unknown why some patients with inflammatory bowel disease develop primary sclerosing cholangitis. We have recently shown that patients with primary sclerosing cholangitis have an increased prevalence of mutations in the gene responsible for cystic fibrosis (CFTR) compared with individuals with inflammatory bowel disease alone. Our aim was to examine whether induction of colitis by oral dextran leads to bile duct injury in mice heterozygous or homozygous for mutations in CFTR. The effect of oral administration of docosahexaenoic acid to correct a fatty acid imbalance associated with cystic fibrosis was also examined to determine whether this would prevent bile duct inflammation. Wild-type mice and mice heterozygous and homozygous for CFTR mutations were given dextran orally for 14 days to induce colitis. Bile duct injury was quantitated by blinded histological scoring and measurement of serum alkaline phosphatase activity. The effect of pretreatment with docosahexaenoic acid for 7 days was examined. Treatment of mice with 100 mg dextran/day for 9 days followed by 85 mg/day for 5 days resulted in a significant increase in bile duct injury as determined by histological scoring in homozygous cystic fibrosis mice compared with wild-type mice (P = 0.005). The bile duct injury seen in cystic fibrosis mice was reflected in a threefold increase in serum alkaline phosphatase (P = 0.0006). Pretreatment with oral docosahexaenoic acid decreased both histological evidence of bile duct injury and serum alkaline phosphatase levels. In the setting of colitis, loss of CFTR function leads to bile duct injury.

Analysis of cystic fibrosis gener product (CFTR) function in patients with pancreas divisum and recurrent acute pancreatitis

BACKGROUND

The mechanism by which pancreas divisum may lead to recurrent episodes of acute pancreatitis in a subset of individuals is unknown. Abnormalities of the cystic fibrosis gene product (CFTR) have been implicated in the genesis of idiopathic chronic pancreatitis. The aim of this study was to determine if CFTR function is abnormal in patients with pancreas divisum and recurrent acute pancreatitis (PD/RAP).

METHODS

A total of 69 healthy control subjects, 12 patients with PD/RAP, 16 obligate heterozygotes with a single CFTR mutation, and 95 patients with cystic fibrosis were enrolled. CFTR function was analyzed by nasal transepithelial potential difference testing in vivo. The outcomes of the PD/RAP patients following endoscopic and surgical treatments were concomitantly analyzed.

FINDINGS

Direct measurement of CFTR function in nasal epithelium in response to isoproterenol demonstrated that the values for PD/RAP were intermediate between those observed for healthy controls and cystic fibrosis patients. The median value was 13 mV for PD/RAP subjects, which was statistically different from healthy controls (22 mV, p= 0.001) and cystic fibrosis pancreatic sufficient (-1 mV, p < 0.0001) and pancreatic insufficient (-3 mV, p < 0.0001) patients.

INTERPRETATIONS

These results suggest a link between CFTR dysfunction and recurrent acute pancreatitis in patients with pancreas divisum and may explain why a subset of patients with pancreas divisum develops recurrent acute pancreatitis.

Increased prevalence of CFTR mutations and variants and decreased chloride secretion in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) and cystic fibrosis (CF) are both slowly progressive cholestatic liver diseases characterized by fibro-obliterative inflammation of the biliary tract. We hypothesized that dysfunction of the CF gene product, cystic fibrosis transmembrane conductance regulator (CFTR), may explain why a subset of patients with inflammatory bowel disease develop PSC. We prospectively evaluated CFTR genotype and phenotype in patients with PSC ( n=19) compared with patients with inflammatory bowel disease and no liver disease ( n=18), primary biliary cirrhosis ( n=17), CF ( n=81), and healthy controls ( n=51). Genetic analysis of the CFTR gene in PSC patients compared with disease controls (primary biliary cirrhosis and inflammatory bowel disease) demonstrated a significantly increased number of mutations/variants in the PSC group (37% vs 8.6% of disease controls, P=0.02). None of the PSC patients carried two mutations/variants. Of PSC patients, 89% carried the 1540G-variant-containing genotypes (resulting in decreased functional CFTR) compared with 57% of disease controls ( P=0.03). Only one of 19 PSC patients had neither a CFTR mutation nor the 1540G variant. CFTR chloride channel function assessed by nasal potential difference testing demonstrated a reduced median isoproterenol response of 14 mV in PSC patients compared with 19 mV in disease controls ( P=0.04) and 21 mV in healthy controls ( P=0.003). These data indicate that there is an increased prevalence of CFTR abnormalities in PSC as demonstrated by molecular and functional analyses and that these abnormalities may contribute to the development of PSC in a subset of patients with inflammatory bowel disease.

Multicenter randomized trial of the spiral Z-stent compared with the Wallstent for malignant biliary obstruction

BACKGROUND

The industry standard since 1990 for self-expanding biliary metallic stents has been the Wallstent. In 1998 the Spiral Z-stent was released. This randomized trial compared the Z-stent with the Wallstent in the treatment of malignant biliary obstruction.

METHODS

Patients with unresectable malignant biliary obstruction distal to the bile duct bifurcation were randomized to receive a 10-mm diameter Wallstent or a 10-mm diameter Z-stent.

RESULTS

A total of 145 patients were randomized; 13 were excluded. Sixty-four patients who received a Z-stent and 68 who had a Wallstent are included in the analysis. Tumors responsible for bile duct obstruction were pancreatic cancer (108), cholangiocarcinoma (15), metastatic cancer (6), and papillary cancer (3). Metallic stents were successfully placed in all patients. Seven technical problems were encountered during placement of the Z-stent and 5 with the Wallstent. There were 21 occlusions requiring reintervention (8 Z-stent, 13 Wallstent; p = 0.30). Median time to reintervention was the following: Z-stent, 162 days; Wallstent, 150 days (p = 0.22). A total of 104 patients died of progressive disease or other cause; 7 patients remain alive with patent stents. The overall calculated median patency rates were: Z-stent, 152 days; Wallstent, 154 days (p = 0.90).

CONCLUSIONS

The Spiral Z-stent is comparable with the Wallstent in terms of placement, occlusion rates, and overall patency. Occasional early occlusion of both stents suggests tumor characteristics instead of the size of the mesh openings in the stents as important factors.

Gastrointestinal problems in the chronically critically ill patient

In summary, a variety of gastrointestinal processes may occur in the chronically critically ill patient population, usually as consequence of the primary systemic process. The clinical presentation is frequently nonclassic and there often is a substantial delay in diagnosis, resulting in increased morbidity and mortality.

Primary gallbladder cancer: recognition of risk factors and the role of prophylactic cholecystectomy

The objective of this article is to review the available literature on the epidemiology, predisposing factors, and conditions associated with primary gallbladder cancer, and to discuss the role of prophylactic cholecystectomy in high-risk patient populations. Gallbladder cancer is a highly malignant tumor with a poor 5-yr-survival rate. It is a tumor of the elderly and has striking genetic, racial, and geographic characteristics, with an extremely high prevalence in Native Americans and Chileans. Cholelithiasis is a well-established risk factor for gallbladder cancer and the risk seems to correlate with stone size. Polyps that are >1 cm, single, sessile, and echopenic are associated with a higher risk of malignancy. Anomalous junction of pancreaticobiliary ducts (AJPBD), especially without choledochal cyst, and porcelain gallbladder are additional factors that predispose to gallbladder cancer. Lesser associations include chronic bacterial infections of the gallbladder, typhoid carrier state, certain occupational and environmental carcinogens, hormonal changes in women, and certain social, dietary, and familial factors. It is important to identify high-risk groups for gallbladder cancer because of the dismal nature of this tumor. In patients with porcelain gallbladder and anomalous junction of the pancreatic and biliary ducts, cholecystectomy is recommended provided that the patient is a good operative candidate. Patients with large solitary polyps or gallstones require close ultrasonic follow-up. With the advent of endoscopic ultrasound it is expected that early changes of malignancy in polyps will be reliably detected, and more patients will potentially be cured with a simple cholecystectomy. Through a MEDLINE/PAPERCHASE search we identified and reviewed articles regarding gallbladder cancer published in English-language journals between 1966 and 1999, using the key words biliary tract and gallbladder diseases, cancer, neoplasms, surgery, cholelithiasis, gallstones, cholecystitis, gallbladder polyps, risk factors, chemical industry, occupational diseases, typhoid, porcelain gallbladder, bacteremia, and precancerous conditions. We also used the bibliography of relevant articles to increase our search. A total of 122 publications were selected using the mentioned data source.