Hereditary pancreatitis and the risk of pancreatic cancer. International Hereditary Pancreatitis Study Group

BACKGROUND

Hereditary pancreatitis is an autosomal-dominant disease, with a variable expression and an estimated penetrance of 80%. The gene for this disease has recently been mapped to chromosome 7q35, and the defect is believed to be caused by a mutation in the cationic trypsinogen gene. Acute attacks of abdominal pain begin early in life and the disease often progresses to chronic pancreatitis. Although the risk of pancreatic cancer is thought to be increased in more common types of chronic pancreatitis, the frequency of pancreatic cancer in the inherited type of pancreatitis is uncertain.

PURPOSE

The aim of this study was to assess the frequency of pancreatic cancer and other tumors in patients with hereditary form of pancreatitis.

METHODS

To determine the natural history of hereditary pancreatitis, we invited all members of the American Pancreatic Association and the International Association of Pancreatology to participate in a longitudinal study of this rare form of pancreatitis. The initial criteria for patient eligibility were as follows: early age (< or = 30 years) at onset of symptoms, positive family history, and absence of other causes. From April 1995 through February 1996, 37 physicians from 10 countries contributed medical records of 246 (125 males and 121 females) patients thought to have hereditary pancreatitis as the most likely diagnosis. This group included 218 patients where the diagnosis appeared to be highly probable and 28 additional patients where the diagnosis of hereditary pancreatitis was less certain: 25 patients who had relatively late onset of disease and a positive family history and three patients with onset of disease before age 30 years but with an uncertain family history. We reviewed all causes of death and compared the observed to the expected frequency of cancer in this historical cohort of patients with hereditary pancreatitis. The strength of the association between pancreatitis and pancreatic cancer was estimated by the standardized incidence ratio (SIR), which is the ratio of observed pancreatic cancer cases in the cohort to the expected pancreatic cancers in the background population, adjusted for age, sex, and country.

RESULTS

The mean age (+/- standard deviation [SD]) at onset of symptoms of pancreatitis was 13.9 +/- 12.2 years. Compared with an expected number of 0.150, eight pancreatic adenocarcinomas developed (mean age +/- SD at diagnosis of pancreatic cancer: 56.9 +/- 11.2 years) during 8531 person-years of follow-up, yielding an SIR of 53 (95% confidence interval [CI] = 23-105). The frequency of other tumors was not increased: SIR = 0.7 (95% CI = 0.3-1.6). Eight of 20 reported deaths in the cohort were from pancreatic cancer. Thirty members of the cohort have already been tested for the defective hereditary pancreatitis gene: all 30 carry a mutated copy of the trypsinogen gene. The transmission pattern of hereditary pancreatitis was known for 168 of 238 patients without pancreatic cancer and six of eight with pancreatic cancer. Ninety-nine of the 238 patients without pancreatic cancer and six of the patients with pancreatic cancer inherited the disease through the paternal side of the family. The estimated cumulative risk of pancreatic cancer to age 70 years in patients with hereditary pancreatitis approaches 40%. For patients with a paternal inheritance pattern, the cumulative risk of pancreatic cancer is approximately 75%.

CONCLUSIONS

Patients with hereditary pancreatitis have a high risk of pancreatic cancer several decades after the initial onset of pancreatitis. A paternal inheritance pattern increases the probability of developing pancreatic cancer.

Beta-casomorphin (BCM) and human colonic lamina propria lymphocyte proliferation

BCM is a milk-derived peptide with opiate-like properties which is absorbed through the gastrointestinal mucosa. It has been shown to affect gastrointestinal motility, absorption and secretion. Recently, modulation of the immune system by BCM was also reported. In this study we investigated the in vitro effect of BCM on the human mucosal immune response as represented by lamina propria lymphocyte (LPL) proliferation. Results show that BCM significantly inhibited concanavalin A (ConA) stimulated LPL DNA synthesis. BCM also inhibited ornithine decarboxylase activity (ODC) in ConA-stimulated LPL. Although BCM also inhibited 12-O-tetradecanoyl phorbol-13-acetate (TPA) stimulated LPL DNA synthesis, the degree of inhibition was much lower than in ConA-stimulated LPL. The anti-proliferative effect of BCM was reversed by the opiate receptor antagonist, neloxone. Our results suggest that BCM may affect the human mucosal immune system, possibly via the opiate receptor.

Propofol sedation for endoscopic procedures in children

BACKGROUND AND STUDY AIMS

Propofol sedation has been used successfully in various outpatient minor procedures in children. Limited data are available on the usefulness of propofol sedation during gastrointestinal endoscopic procedures in children. The aim of this study was to evaluate our experience of propofol sedation in pediatric gastrointestinal endoscopic procedures.

MATERIALS AND METHODS

The charts of all children who had undergone diagnostic endoscopic procedures, and were sedated by propofol, were retrospectively reviewed. Demographic data, cardiovascular monitoring, and drug dosages were recorded. Patients evaluated their sedation efficacy by answering a questionnaire before discharge.

RESULTS

A total of 104 children underwent 107 procedures. Propofol alone was given in 19 procedures and in combination with midazolam and/or fentanyl in 88 procedures. All procedures were completed and significant complication occurred in only one patient. No significant difference was observed in the amount of sedative drugs or recovery time between upper and lower endoscopic procedures. A lower propofol dosage was needed when a combination of drugs was given compared to propofol drug alone. Patients' assessment of their sedation showed that the vast majority had experienced postendoscopic amnesia.

CONCLUSION

Propofol sedation for endoscopic procedures is safe and acceptable for children. Propofol sedation should be offered to young children, especially those who express significant anxiety.

A prospective randomized study with mineral oil and oral lavage solution for treatment of faecal impaction in children

Faecal impaction with or without encopresis is a very common problem. We performed a randomized, open-label, prospective study to compare the efficacy and acceptability of the treatment of faecal impaction using either mineral oil or pineapple-flavoured isotonic intestinal lavage solution containing polyethylene glycol-3350 (Colyte). Thirty-six patients over 2 years of age were randomized to receive either mineral oil or flavoured lavage solution. The dose of mineral oil was 2 to 8 tablespoons twice a day for two days (17 patients--Group I) and of lavage solution was 20 ml/kg/h for 4 hours on two consecutive days (19 patients--Group II). The patients were assessed for the presence of abdominal faecal masses, presence and consistency of rectal mass, perineal soiling before and two days after either of the randomly assigned treatment. The patients and parents were asked regarding the compliance with treatment, side-effects, number of bowel movements after treatment and willingness to try similar treatment if faecal impaction recurred. Patients in the lavage group had more frequent bowel movements, and showed more effective clearance of abdominal and rectal lumps (P < 0.01) at the time of repeat examination at two days. However, they had some vomiting and were less compliant (P < 0.01) when compared to mineral oil patients. We conclude that balanced lavage solution effectively relieves faecal impaction, however, compliance with its use is poorer than that with mineral oil.

Non-Helicobacter pylori related duodenal ulcer disease in children

BACKGROUND

In spite of the worldwide distribution of Helicobacter pylori infection, recent data have reported an increased rate of non-H. pylori, non-NSAIDs-duodenal ulcer disease in adults. The estimated rate of these ulcers in children is unknown. We aimed to investigate the prevalence of non-H. pylori, non-NSAIDs-peptic ulcer disease in our pediatric patients who undergo upper endoscopic procedures.

METHODS

A retrospective analysis of 622 upper endoscopic reports was performed. Reports that documented mucosal ulcerations were included in our study. The demographic, clinical, endoscopic, and histological data were retrieved. The H. pylori-negative, duodenal/gastric ulcer-positive patients were compared with H. pylori-positive, duodenal/gastric ulcer-positive patients.

RESULTS

Out of the 622 upper endoscopy reports, a total of 11 (1.8%) children with mucosal ulceration were studied. Mucosal ulceration was distributed in the following locations: stomach-3 (27%), and duodenal bulb-10 (91%) (two children had ulcers in both the stomach and duodenal bulb). Helicobacter pylori infection was only detected in three (27%) children with duodenal ulcer. Gastritis was more severe in patients with H. pylori infection/duodenal ulcer compared with H. pylori-negative/duodenal ulcer group. No statistical difference in clinical symptoms or endoscopic appearance was observed between the H. pylori-negative and H. pylori-positive groups.

CONCLUSION

'Idiopathic' (H. pylori-negative, NSAIDs-negative) duodenal/gastric ulcers are present in symptomatic children. Clinical or endoscopic characteristics are insufficient markers to identify those 'idiopathic' ulcers. Investigating the 'risk factors' for those ulcers will be helpful in reducing the morbidity in these children.

Polyamine levels, ornithine decarboxylase (ODC) activity, and ODC-mRNA expression in normal and cancerous human colonocytes

Ornithine decarboxylase (ODC) and polyamines (putrescine, spermidine, and spermine) are crucial for cell proliferation. Recently, elevated ODC activity and polyamine levels have been suggested as biological markers for human colon cancer. In this study, we measured ODC activity and the levels of polyamines (putrescine, spermidine, spermine, and cadaverine) and acetyl-putrescine in human colonocytes isolated from cancerous areas compared to the adjacent normal colon tissue. In addition, ODC mRNA expression was compared between both groups. We found that colonocytes isolated from cancerous areas had significantly higher mean value of ODC activity, putrescine, spermidine, spermine, and cadaverine levels up to 1480%, 470%, 260%, 380%, and 510% respectively compared to colonocytes isolated from the adjacent normal colonic mucosa. No difference was found in acetyl-putrescine levels between cancerous and normal colonocytes. Steady-state levels of ODC mRNA were slightly elevated in cancerous colonocytes relative to normal colonocytes in two of three paired samples. However, the increase in ODC mRNA levels is not sufficient to account for the increase in ODC activity suggesting that colonocyte ODC activity is regulated post-transcriptionally.

Prospective comparison of rapid urease tests (PyloriTek, CLO test) for the diagnosis of Helicobacter pylori infection in symptomatic children: a pediatric multicenter study

OBJECTIVE

Rapid urease tests are reliable methods to diagnose Helicobacter pylori (HP) infection in the endoscopy suite. The PyloriTek test kit is a new rapid urease test that has the advantage of a 1-h final reading. The aim of this study was to compare the accuracy of PyloriTek and the test in the diagnosis of H. pylori infection in children.

METHODS

Children from four different pediatric gastroenterology centers were recruited prospectively into the study. These children were >5 yr old and had an upper endoscopy procedure. Antral biopsies were examined for both rapid urease tests in the endoscopy suite, and others were sent for routine histological examination.

RESULTS

A total of 242 children were recruited into the study over approximately 1 yr. The concordance between PyloriTek and CLO test was 98% (238 of 242). Twenty-five children were positive for HP organisms by PyloriTek and CLO test, whereas four children were positive by PyloriTek but negative by CLO test. PyloriTek was comparable to CLO test for the diagnosis of HP organisms and HP-associated gastritis. Moreover, in 48% of the positive results, PyloriTek gave significantly faster results than CLO test.

CONCLUSIONS

We conclude that PyloriTek is an appropriate rapid urease test to use in children and may have an advantage over the CLO test because of its shorter reading time.

Chronic multifocal symmetrical osteomyelitis. Report of two cases in Bedouin infants

Chronic multifocal symmetrical osteomyelitis is a rare condition characterized clinically and radiologically by multiple symmetrical bone lesions, a benign course, and a good prognosis. To our knowledge, only 25 cases have been reported in the literature; all of them occurred in patients of European ancestry. We describe two bedouin children, aged 20 and 21 months, who suffered from this disease. Although they complained of one painful joint, multiple osteolytic lesions were found in the long bones. At follow-up six months later, the children were in perfect condition without radiologic sequelae.

Prevalence of CagA, VacA antibodies in symptomatic and asymptomatic children with Helicobacter pylori infection

BACKGROUND

Limited data are available on the prevalence of CagA and VacA Helicobacter pylori antibodies in children. The aim of this study was to investigate the antibody prevalence to the H. pylori virulence factors CagA and VacA in symptomatic and asymptomatic children with H. pylori infection and to correlate these antibodies with the severity of gastric inflammation or density of H. pylori organisms in the gastric mucosa.

MATERIALS AND METHODS

Twenty-three symptomatic children and 132 asymptomatic children with positive H. pylori serology participated in this study. Anti-H. pylori IgG antibody and CagA or VacA H. pylori antibodies were measured by enzyme immunoassay (HM-CAP; sensitivity and specificity > 90%) and Western immunoblot (Helicoblot 2.0) methods, respectively. Gastric inflammation and H. pylori density were graded histologically using the revised Sydney criteria.

RESULTS

The prevalence of CagA and VacA antibodies were 69% and 35% in symptomatic children and 54% and 52% in asymptomatic children, respectively. Multiple regression analysis showed a correlation between CagA antibody and the severity of gastritis but no correlation with other histological features, including the number of neutrophils or lymphoid follicles. Neither antibody correlated with the degree of bacterial density in the gastric mucosa.

CONCLUSION

CagA and VacA H. pylori antibodies are common in the pediatric population. The combined CagA/VacA antibodies correlated weakly with the degree of mucosal inflammation.

Modulation of human colonic lamina propria lymphocyte proliferation. Effect of bile acids and oxidized fatty acids

Bile acids were been implicated in several pathologic processes, such as secretory diarrhea, carcinogenesis, and immunomodulation of human peripheral blood lymphocytes. Nevertheless, their effect on the human gut immune system is not known. In this study we investigate the effect of several bile acids (cholate, deoxycholate, chenodeoxycholate) and 13-hydroperoxylinoleic acid (conc. 0.1-1000, microM) on human colonic lamina propria lymphocyte (LPL) DNA synthesis and cell proliferation. In addition, the effect of these bile acids on LPL ornithine decarboxylase activity was also determined. Significant dose-dependent inhibition of [3H]thymidine incorporation in Con A-stimulated LPL was observed. Parallel inhibition was seen on LPL cell proliferation. Furthermore, bile acids inhibited ornithine decarboxylase activity in Con A-stimulated LPL. These effects on cell proliferation were not due to the LPL cytolysis as viability and cell membrane integrity were not altered. Our results suggest that bile acid has an immunoregulatory function on the human mucosal immune system and may have a role during pathological states.

Prevalence of Helicobacter pylori infection in children from urban and rural West Virginia

Our objective was to evaluate the prevalence rate of Helicobacter pylori (HP) in children from urban and rural areas of West Virginia. In all, 1164 blood samples were collected from children who attended a local health fair, pediatric clinics, and emergency departments of four different hospitals located in urban and rural counties. Socioeconomic status was determined in 303 children. Serum HP antibody (IgG) was measured by enzyme immunoassay (EIA). A total of 468 (40%) samples were HP positive. HP acquisition correlated with increasing age, family crowding, and community location (urban/rural) but not with gender, water source used (city/well), or socioeconomic status. The prevalence rate of HP in the children of West Virginia is higher than any data previously reported from the United States. The results correlated with only few socioeconomic criteria, suggesting that other factors may contribute to the increased prevalence of HP infection in the children of West Virginia.

Helicobacter pylori antibody profile in household members of children with H. pylori infection

Intrafamilial spread is implicated as a major route for acquisition of Helicoobacter pylori infection. Investigating H. pylori cytotoxin-associated protein (CagA) and vacuolating toxin (VacA) antibodies within family members enabled the authors to evaluate this possibility further. Serum samples were collected prospectively from household members after their index children were diagnosed with active H. pylori infection. Serum samples were evaluated for anti-H. pylori immunoglobulin G antibody using the enzyme immunoassay (IEA) method and for H. pylori CagA and VacA antibodies with the commercially available immunoprobing Western blot kit. Ten different families participated in the study, including 10 pediatric patients and 31 household members. All patients and 28 household members (90%) were seropositive for H. pylori antibody by IEA and Western blot tests. Overall, 17 subjects (41.4%) were CagA positive, 14 (34.1%) were VacA positive, 11 (26.8%) were positive for both antibodies, and 22 (53.6%) were negative for both antibodies. A significant association in bacterial antibody profile was found between the patient index members and all household members (Cohen's kappa and Mentel-Haenszel methods). In four families, more than 66% of the household members harbored the same antibody profile, and in two families a completely different profile was observed. Moreover, a similar H. pylori antibody profile between the index patient and the mother was found in six families, and between the index patient and the father in two families. The data strongly suggest an intrafamiliar transmission for H. pylori infection.

Comparison between a rapid office-based and ELISA serologic test in screening for Helicobacter pylori in children

BACKGROUND

The rapid diagnostic serological test for detection of Helicobacter pylori (H. pylori) infection in children has a significant advantage over the standard enzyme immunoassay (EIA) method, for its simplicity and rapid availability of results in a physician's office setting. We compared the immunochromatographic test with a standard enzyme immunoassay test in the pediatric population.

MATERIALS AND METHODS

A retrospective analysis of 1147 serum samples from asymptomatic children and prospective analysis of 62 serum samples from symptomatic children undergoing diagnostic upper endoscopy were evaluated for the detection of H. pylori antibody by two commercially available serology tests. Each serum sample was tested by a rapid test (FlexSure HP, SmithKline Diagnostics, Inc.) and compared to the standard EIA method (HM-CAP, Enteric Products, Inc.).

RESULTS

The rapid test, FlexSure HP, was comparable to the rapid EIA test in screening for H. pylori infection in symptomatic and asymptomatic children with sensitivity and specificity of 83-90% and 90-100%, respectively. Both methods had a comparable sensitivity and specificity for the detection of H. pylori-associated gastritis (60-70% and 94%, respectively).

CONCLUSION

The rapid test is comparable to the standard EIA test and may be used by physicians in symptomatic children. The use of FlexSure HP as a screening tool for the prevalence of H. pylori infection in asymptomatic children may be limited by its low positive predictive value compared to the EIA method.

Neuropeptide Y (NPY) enhances proliferation of human colonic lamina propria lymphocytes

Neuropeptide Y (NPY) is one member of a family of peptides with a wide range of physiological effects on the CNS, cardiovascular, and respiratory systems. NPY is widely distributed throughout the peripheral and central nervous systems. It has also been found within the colon, liver and gallbladder in close anatomic proximity to the mucosal immune system. In this study, we investigated the effect of NPY on human gut mucosal immune function. We examined colonic lamina propria lymphocyte (LPL) proliferation by measuring DNA synthesis, ornithine decarboxylase (ODC) activity, and polyamine biosynthesis. NPY enhanced ODC activity and polyamine biosynthesis in Con A-stimulated LPL, and enhanced thymidine incorporation into Con A-stimulated LPL but not into monocyte-depleted LPL. Moreover, exogenous IL1-beta partially restored NPY's stimulatory effect on monocyte-depleted LPL DNA synthesis. Our results demonstrate that NPY enhances human colonic LPL proliferation and that this effect is partially IL1-beta dependent. Our data also suggest that NPY's effect may be mediated via polyamine biosynthesis. We postulate that the NPY may have an important impact on human mucosal immune function.

Is gastric nodularity a sign for gastric inflammation associated with Helicobacter pylori infection in children?

The aim of this study was to investigate the accuracy of using gastric nodularity (GN) as a marker for gastric inflammation associated with Helicobacter pylori infection in children. A retrospective analysis of 395 upper endoscopies done in children between 1990-1996 was performed. Demographics, clinical symptoms, endoscopic features, rapid urease test (RUT), and histological results were collected from each report. GN was found in 13 (3.5%) children. GN showed a significant correlation with age but not with gender. Multiple regression analysis showed a significant correlation between GN and gastritis with RUT but not with other histological determinants alone (gastritis, RUT, or H. pylori organisms). Nevertheless, GN had a poor accuracy rate to determine H. pylori-associated gastritis (sensitivity, 61%; positive predictive value, 12%). GN is a poor predictor for gastric inflammation associated with H. pylori infection in children. During endoscopy, gastric biopsies should always be obtained in children to establish the presence of mucosal inflammation.

Criteria map audit of scorpion envenomation in the Negev, Israel

A criteria map audit is a medical record audit in which quality of care is evaluated according to algorithmically arranged criteria. Thus, a particular criterion is applied to the patient record only if other criteria have been met. For example, if a stung child's condition is severe but not life threatening and if he has had a positive skin test for antivenom sensitivity then he should receive antivenom only after receiving adrenaline and hydrocortisone. We used a modified criteria map audit to determine both the clinical picture of scorpion envenomation and quality of care process in 94 children. Related outcomes of care measured included mortality, persistent morbidity, allergic reaction to scorpion antivenom and length of stay in hospital. Scorpion stings in the Negev region are usually due to the yellow scorpion, L. quinquestriatus, and usually occur in the summer months on the extremities in exposed male children under 10. The clinical picture is more severe when the scorpion is yellow, when the child is younger and when the sting is on the trunk or head. Symptoms apparently mediated by the central nervous system (2.6 findings/child) were more frequent than parasympathetic symptoms (2.3 findings/child). Treatment with antivenom and specific therapy for complications led to very low persistent morbidity and mortality in symptomatic cases, but was also accompanied by a longer hospital stay (64% equal to or greater than 3 days) than for asymptomatic cases (18% equal to or greater than 3 days). Testing for antivenom sensitivity was omitted in an unacceptably high percentage of cases (69%) and its omission led to an allergic reaction in 4 out of 40 cases (10%). Inadequacy in treatment of 7 secondary clinical problems ranged from 71% for hypertension to 29% for seizures (mean 46%). Persistent morbidity was negligible and mortality was 1.2%. We conclude that criteria map audit can be used to describe the clinical and epidemiological picture of a clinical problem while at the same time providing an audit of the process of care.

The inhibition effect of cholecystokinin in human colonic lamina propria lymphocyte proliferation, and reversal by the cholecystokinin receptor antagonist L-364718

Cholecystokinin (CCK) is a potent neuropeptide hormone with activity on various gastrointestinal organs during the digestive process. It was recently suggested that CCK may also act on the immune system. In this study we investigated the effect of CCK on the human mucosal immune system as represented by colonic lamina propria lymphocytes (LPL). Our results demonstrated that CCK at concentrations of 10(-13) M to 10(-7) M inhibits thymidine incorporation into Con A-stimulated LPL DNA by up to 40%. Moreover, this inhibitory effect was reversed by the specific CCK receptor antagonist, L-364718, at concentrations of 10(-8) M to 10(-5) M. In addition, CCK did not affect DNA synthesis of LPL stimulated with phorbol ester (PDB) and calcium ionophore (ionomycin). It is postulated that the CCK effect may involve intracellular metabolic steps proximal to protein kinase C activation and calcium flux. Our results suggest that CCK may play a role in modulating the human mucosal immune system during digestion and thus, should be added to the list of the neuropeptides that affect the mucosal immune system.

The use of an oral fluid immunoglobulin G ELISA for the detection of Helicobacter pylori infection in children

BACKGROUND

Enzyme linked immunosorbent assay (ELISA) evaluation of oral fluid immunoglobulin G (IgG) antibodies to Helicobacter pylori is a unique approach for both epidemiological studies and the diagnosis of infection, especially in children. The use of oral fluid sampling to evaluate specific H. pylori IgG antibodies has advantages over serum, including reduced biohazard risk and noninvasive collection. Oral fluid sampling is fast and involves minimal patient discomfort. Since children facilitate transmission of H. pylori infection, a simple, accurate, noninvasive diagnostic test is necessary for large epidemiologic studies. The aim of our study was to evaluate a new oral fluid ELISA for detection of IgG antibodies to H. pylori in children.

MATERIALS AND METHODS

We compared this new oral fluid ELISA with the HM-CAPTM serum ELISA and gastric biopsy histology using 779 oral fluid samples from children collected at 11 clinical sites across the United States. This cohort included 315 children symptomatic for abdominal pain and 464 asymptomatic. All samples were evaluated in a double blind manner. The oral fluid ELISA demonstrated a sensitivity of 76.2% and a specificity of 94.0% in children 2 months old to 201/2 years, as compared with the HM-CAPTM serologic assay. The assay's sensitivity improved to 81.3% in children aged 5 or greater and the specificity remained at 94.0%. When compared with gastric biopsy histology in the same age group, the oral fluid ELISA demonstrated a sensitivity of 71.7% and a specificity of 90.4%.

RESULTS

This new oral fluid ELISA is moderately sensitive and offers a very specific method for detecting H. pylori infection in older children, but it is of little value in children under the age of 5 years.

CONCLUSIONS

Overall, we conclude that this oral fluid ELISA does not appear to be a helpful clinical tool for the diagnosis of H. pylori infection in children.

Gastrointestinal neuropeptides suppress human colonic lamina propria lymphocyte DNA synthesis

Gastrointestinal neuropeptides have been shown to modulate the circulatory immune system, but their effect on the mucosal immune system is not well defined. We studied the effect of VIP, SOM, S-P and Bomb on thymidine incorporation into human colonic lamina propria lymphocyte (LPL) DNA. Physiologic concentrations of VIP, SOM, S-P and Bomb significantly suppressed thymidine incorporation into Con A-stimulated human LPL. These neuropeptides did not affect DNA synthesis when LPL were induced with phorbol ester (PDB) and calcium ionophore (ionomycin). Our data suggest that a) VIP, SOM, S-P, and Bomb may have a regulatory role in the human mucosal immune system, and b) Bomb should be added to the list of neuropeptides which affect the gut immune system.

Mucosal origin and shedding of an early colonic tumor marker defined by Adnab-9 monoclonal antibody

Recent attention has been drawn to the diagnostic potential of tests based on shed colonic tumor markers. Adnab-9 monoclonal antibody raised against neoplastic, potentially premalignant colonic adenomas recognizes a marker in colonic effluent or tissue which correlates with the presence of tumors or risk of colorectal cancer. The origin of this antigen and optimal collection of colonic effluent were investigated by enzyme-linked immunosorbent assay and Western blotting. Mean Adnab-9 binding in effluent samples from colorectal cancer patients even after resection is high as compared with that in normal subjects (P < 0.05). Effluent samples are best collected in the morning hours. Antigen proteolysis may be significant depending on the site and timing of effluent collection, but breakdown products are reactive. Tissue and effluent Adnab-9 binding at any one anatomic site of collection appear to correlate (r = 0.88, P = 0.01). The Adnab-9 antigen is constitutively expressed at low levels throughout the distal bowel and localized to the deepest regions of the mucosal crypts. Other than meconium, no significant levels of binding are found in other body fluids. This antigen is specific for the gastrointestinal tract, its binding in conveniently collected effluent samples correlates with tissue content, and the antigen is constitutively expressed in the crypts of the distal small bowel and colonic mucosa.

Inhibition of ornithine decarboxylase activity decreases polyamines and suppresses DNA synthesis in human colonic lamina propria lymphocytes

Ornithine decarboxylase (ODC) and the polyamines are essential for cell proliferation in a variety of cells including lymphocytes. In this study, we investigated the potential role of ODC and polyamines in human colonic lamina propria lymphocytes (LPL) compared to peripheral blood lymphocytes (PBL). Our results show that con A stimulation of LPL and PBL was associated with marked increases in ODC and polyamines. The specific inhibitor of ODC, alpha-difluoromethylornithine (DFMO), resulted in a complete inhibition of ODC activity and depletion of putrescine, spermidine and spermine levels. DFMO also suppressed DNA synthesis of LPL and PBL by up to 48% and 62% respectively. This antiproliferative effect was reversed by adding back the polyamines putrescine (1 mM), spermidine (10 microM) or spermine (10 microM) to the culture medium. We conclude that ODC and the polyamines are important for human LPL proliferation, and hence may play a role in human mucosal immune function.

Detection of Helicobacter pylori organisms by Hp-fast in children

Hp-fast is a new rapid urease test (RUT) that has not been evaluated in children. The aim of the study was to prospectively compare the Hp-fast test to the CLOtest in children. Children with gastrointestinal symptoms who undergo diagnostic upper endoscopy were prospectively enrolled to the study. Antral gastric biopsies were evaluated for histology and for CLO-test and Hp-fast. Results were then compared to histology. Of the 94 children who participated, gastritis was found in 38 (40%), of whom 16 (42%) had associated H. pylori organisms. In two children, H. pylori organisms were identified without gastritis. The concordance between both RUT tests was 98%. A significant correlation was found between RUT results and histological factors or serology. The accuracy rate of both RUT increased significantly when different gold standards were utilized to detect Hp infection in children. The best correlation was found when histology and serology were considered as the gold standard for the diagnosis of H. pylori infection in children (sensitivity: 100% compared to 43-80% with other standards, respectively). In conclusion, the Hp-fast test result is comparable to CLOtest, but neither alone is sufficient to establish the diagnosis of Hp infection in children.