The -295T-to-C promoter polymorphism of the IL-16 gene is associated with Crohn's disease

Recently, a T-to-C polymorphism at position -295 in the promoter region of the human interleukin-16 (IL-16) gene was reported. The expression of IL-16 is increased in inflammatory bowel disease, in particular in Crohn's disease. However, data concerning the IL-16 promoter polymorphism in inflammatory bowel disease are lacking. Thus, the current study aimed at the assessment of this polymorphism in Crohn's disease and ulcerative colitis. One hundred three patients with Crohn's disease, 100 patients with ulcerative colitis, and 120 healthy unrelated controls were genotyped for the promoter polymorphism. Furthermore, patients with Crohn's disease were stratified according to disease localization and the respective clinical phenotype (fistulizing, fibrostenotic, or inflammatory). The frequencies of the T allele (P < 0.01) and the TT genotype (P < 0.01) were significantly increased in patients with Crohn's disease compared to the controls, regardless of the disease phenotype or the site of intestinal involvement. An association with ulcerative colitis was not observed. Herein a new association between a promoter polymorphism of the IL-16 gene and Crohn's disease was observed and correlates with the previously described increased mucosal expression of IL-16 in inflammatory bowel disease.

Adherence and mental side effects during hepatitis C treatment with interferon alfa and ribavirin in psychiatric risk groups

Psychiatric disorders or drug addiction are often regarded as contraindications against the use of interferon alfa (IFN-alpha) in patients with chronic hepatitis C. Our aim was to obtain prospective data on adherence to as well as efficacy and mental side effects of treatment with IFN-alpha in different psychiatric risk groups compared with controls. In a prospective trial, 81 patients with chronic hepatitis C (positive hepatitis C virus[HCV] RNA and elevated alanine aminotransferase[ALT] level) and psychiatric disorders (n = 16), methadone substitution (n = 21), former drug addiction (n = 21), or controls without a psychiatric history or drug addiction (n = 23) were treated with a combination of IFN-alpha-2a 3 MU 3 times weekly and ribavirin (1,000-1,200 mg/d). Sustained virologic response (overall, 37%) did not differ significantly between subgroups. No significant differences between groups were detected with respect to IFN-alpha-related development of depressions during treatment. However, in the psychiatric group, significantly more patients received antidepressants before and during treatment with IFN-alpha (P <.001). Most of those who dropped out of the study were patients with former drug addiction (43%; P =.04) compared with 14% in the methadone group, 13% in the control group, and 18% in the psychiatric group. No patient in the psychiatric group had to discontinue treatment because of psychiatric deterioration. In conclusion, our data do not confirm the supposed increased risk for IFN-alpha-induced mental side effects and dropouts in psychiatric patients if interdisciplinary care and antidepressant treatment are available. Preexisting psychiatric disorders or present methadone substitution should no longer be regarded as contraindications to treatment of chronic hepatitis C with IFN-alpha and ribavirin in an interdisciplinary setting.

Alterations of the CARD15/NOD2 gene and the impact on management and treatment of Crohn's disease patients

The recent identification of the CARD15/NOD2 gene as a susceptibility locus for Crohn's disease represents an important step towards the delineation of the immunopathogenesis of inflammatory bowel disease. CARD15 functions as an intracellular receptor for bacterial components and thus represents an important link between inflammatory bowel disease and innate immunity. Three major CARD15/NOD2 gene mutations have been associated with Crohn's disease in Caucasians in several independent studies. Together, they explain about 20% of the genetic susceptibility for Crohn's disease. Genotype-phenotype analyses demonstrated an association of these mutations with ileum-specific disease, an increased incidence of the fibrostenotic phenotype and an earlier age of disease onset. Beside these associations, no other relationship between the CARD15/NOD2 genotype and disease behavior or response to treatment has been detailed so far. Thus, the clinical impact of knowing the patient's genotype is limited at this time. Screening for CARD15 mutations in order to identify high-risk individuals or to introduce an individualized disease management is therefore currently not recommended.

Laparoscopic-assisted resection of giant sigmoid lipoma under colonoscopic guidance

Colonic lipomata are rare and mostly asymptomatic lesions; but as they become larger they may produce abdominal pain, constipation, diarrhea, hemorrhage, and intussusception. We report the case of a 75-year-old man who suffered from nonspecific recurrent abdominal pain in the left upper and lower quadrants and had variable episodes of diarrhea and constipation of 4 weeks' duration. During colonoscopy, a giant intraluminal polyp was diagnosed at 35 cm. Abdominal helical computed tomography (CT) revealed a constipating colonic tumor with a diameter of >or=50 mm and density values equal to fat. During laparoscopic surgery in the lithotomy position, the sigmoid and the descending colon were mobilized using a Harmonic scalpel. The origin of the polyp was localized precisely under colonoscopic guidance. The former 12-mm incision in the left lower quadrant was expanded to approximately 70 mm for extracorporal tumor resection. The left and sigmoid colon resections were carried out, and the polyp was removed by full-wall excision. After closure with a single-layer suture, the colon was pushed back into the peritoneal cavity. The patient had an uneventful recovery and was discharged 10 days postoperatively. Histology confirmed a benign lipoma of the descending colon. Laparoscopic-assisted resection under endoscopic guidance proved to be suitable for the removal of large colonic polyps without complications.

[Chronic diarrhea after a journey to Sri Lanka]

A 51-year-old woman was referred for evaluation of chronic diarrhea. She had spent a 14 day vacation in Sri Lanka three years ago. The clinical examination of the patient was unremarkable. Values for protein, iron, zinc, copper and folic acid were decreased and the Shilling- and D-xylose tests revealed pathological results. Gliadin and Endomysium antibodies were not detectable. Histologic examination of the duodenum displayed chronic duodenitis with increased epithelial regeneration and villous atrophy. In the MRI a segment of the mid small bowel with increased thickness of the intestinal wall was described. Abdominal CT-scans demonstrated multiple, enlarged mesenteric lymph nodes. Laparoscopy with biopsies of the ileum and mesenteric lymph nodes excluded a malignant lymphoma, mycobacteriosis or Whipple's disease. Oral therapy with tetracyclines (250 mg q. i. d.) and substitution of folic acid and iron led to rapid improvement of the clinical symptoms which persisted after cessation of the antibiotic therapy. In view of the clinical course tropical sprue has to be assumed despite the short duration of the journey to a tropical region.

[Coagulation system and inflammatory bowel disease: therapeutic and pathophysiologic implications]

Several observations are compatible with an association between an haemostatic imbalance and the pathogenesis of inflammatory bowel disease. The prothrombotic state in Crohn's disease and ulcerative colitis is probably not simply the cause of an increased susceptibility for thrombembolic complications, but might also reflect an important element of the pathogenetic changes observed in the small vessels of the intestinal wall. However, it is still unclear whether alterations in the coagulation system are the cause or the aftermath of the systemic inflammatory response observed in inflammatory bowel disease. Several recent observations describe therapeutic efficacy of unfractioned or low-molecular weight heparin in patients with active ulcerative colitis and Crohn's disease. Based on these clinical observations new concepts concerning the pathophysiology of inflammatory bowel disease have emerged.

A polymorphism in the IL11 gene is associated with ulcerative colitis

Inflammatory bowel diseases (IBD) are multifactorial disorders characterised by the host's inability to limit the inflammatory response to luminal antigens. The association of polymorphisms in the CARD15 gene with Crohn's disease (CD) demonstrates the relevance of activated transcription factor NF(kappa)B in mononuclear cells. Interleukin 11 (IL11) mediates anti-inflammatory effects and is able to downregulate LPS-induced NF(kappa)B activation. The IL11 gene is therefore a good candidate involved in genetic predisposition to IBD. To evaluate the role of the IL11 gene in IBD, two polymorphisms, including a dinucleotide repeat in the promoter region, have been genotyped in 222 patients with CD, 152 patients with ulcerative colitis (UC) and 400 healthy controls. PCR-SSCP analysis of the coding region revealed a single polymorphism in exon 4 leading to an amino acid exchange (G335A; R112H), not significantly associated with either disease. Dinucleotide repeat frequencies of the IL11.A1 allele and of IL11.A1 homozygous individuals were significantly increased among the patients with UC (P < 0.002 and (P < 0.003, respectively) but not with CD. Altered expression of IL11 appears to be involved in the genetic predisposition of UC.

Ulcerative colitis in a patient with Wiskott-Aldrich syndrome

A 30-year-old man with underlying Wiskott-Aldrich syndrome, which is a rare X-linked congenital immunodeficiency syndrome characterized by recurrent infections, thrombopenia, eczema and hematopoietic malignancies, presented with bloody diarrhea. Endoscopic and histological evaluation was compatible with ulcerative colitis. Congenital immune defects are paralleled by enterocolitis mimicking inflammatory bowel disease in a substantial number of patients. Despite therapy with prednisolone and 5-ASA compounds, the patient described here experienced a relapse of the colitis twice. Subsequently a JC virus infection of the central nervous system was diagnosed, and he died due to progressive multifocal leukencephalopathy.

[26-year-old female patient with elevated liver enzymes]

A 26-year-old woman presented with elevated liver enzymes, which were diagnosed two months ago. Examination revealed mild proximal muscle weakness, though the patient herself did not realise any impairment. The abdominal ultrasound and the histology of the liver remained unsuspicious. Muscle biopsy showed vacuolar degeneration, which could be ultrastructurally identified as large deposits of membrane-bound glycogen. The morphological findings prompted biochemical investigations which showed an excess of muscle glycogen. Acid maltase activity was reduced to < 10 % of normal, leading together with the clinical findings to the diagnosis of glycogenosis type II (Pompe's disease) of the adult type. Because of the modest impairment of the patient and the limited therapeutic possibilities, the patient remained thus untreated for.

K-ras mutations in sera of patients with colorectal neoplasias and long-standing inflammatory bowel disease

BACKGROUND

About 50% of colorectal carcinomas and adenomas display K-ras mutations, which have also been described in stool or colonic lavage fluid. Moreover, the presence of K-ras mutations in plasma samples originating from patients with colorectal cancer has been reported recently.

METHODS

DNA was extracted from sera of 16 patients with colorectal carcinomas, 6 with large adenomas, 3 with Crohn disease and 4 with ulcerative colitis. Sera of 20 healthy blood donors served as negative controls. K-ras mutations at the first or second position of codon 12 were detected by an enriched RFLP-PCR method and confirmed by sequencing.

RESULTS

Mutations were found in sera of 5 patients with colorectal carcinomas (31%) and 2 patients with long-standing ulcerative pancolitis (50%), but not in patients with adenomas, Crohn disease or the controls.

CONCLUSIONS

K-ras mutations can be detected in serum samples from patients with manifest colorectal cancer and in patients who display an increased risk for malignant transformation of the colonic mucosa. This observation may have clinical application concerning noninvasive surveillance of these patients. Because of the low sensitivity of this approach it may be useful to combine it with other molecular markers.

A polymorphism in the CD14 gene is associated with Crohn disease

BACKGROUND

Inflammatory bowel diseases (IBD) are multifactorial disorders, characterized by failure to limit the inflammatory response to luminal antigens. Although genetic factors play an important role in the pathogenesis, little is known about the genes accountable. Immune response to intestinal bacteria seems to be crucial in the pathogenesis of IBD.

METHODS

To evaluate the role of the CD14 gene in IBD, a functionally relevant polymorphism in the promoter region (T/C at position -159) has been genotyped in 219 patients with Crohn disease (CD), 142 patients with ulcerative colitis (UC) and 410 healthy controls by RFLP analysis.

RESULTS

T allele and TT genotype frequencies were found increased in CD patients compared to controls (Pc=0.044 and 0.005, respectively).

CONCLUSION

An altered immune response to LPS seems to play a role in the genetic predisposition to CD but not to UC.

Polymorphisms of the ICAM-1 gene are associated with inflammatory bowel disease, regardless of the p-ANCA status

The intercellular adhesion molecule-1 (ICAM-1) is of paramount importance for the initiation and propagation of various inflammatory conditions. An increased frequency of allele R241 of the ICAM-1 gene was previously described in p-ANCA-negative as compared to p-ANCA-positive ulcerative colitis and vice versa in Crohn's disease. One hundred sixteen healthy unrelated controls, 121 patients with ulcerative colitis, and 96 patients with Crohn's disease were genotyped for two polymorphisms of the ICAM-1 gene (R/G241, exon 4; and K/E469, exon 6), employing dot-blot hybridization and stratified according to their p-ANCA status. When compared with the control group the frequency of the allele R241 (P = 0.024) and the heterozygous genotype R/G241, P = 0.032) were significantly increased in ulcerative colitis, whereas the homozygous genotype G/G241 was found less frequently (P = 0.022). The heterozygous genotype K/E469 was observed less frequently (P = 0.001 and 0.037, resp.) than the homozygous genotype E/E469, which was more frequent in Crohn's disease and ulcerative colitis (P = 0.002 and 0.012, respectively). Further significant differences concerning the allele or genotype distribution were not observed. After stratification for the p-ANCA status significant differences concerning the frequencies of both the R241 and the E469 alleles were not detected when p-ANCA-positive inflammatory bowel disease and p-ANCA-negative inflammatory bowel disease were compared. Ulcerative colitis and Crohn's disease are associated with polymorphisms of the ICAM-1 gene, which might therefore represent a functional candidate gene. However, the observed associations are independent of the p-ANCA status.

Weight gain decreases elevated plasma ghrelin concentrations of patients with anorexia nervosa

OBJECTIVE

Ghrelin is a new gastric hormone that has been identified as an endogenous ligand for the growth hormone (GH) secretagogue receptor subtype 1a (GHS-R1a). Ghrelin administration however not only stimulates GH secretion but also induces adiposity in rodents by increasing food intake and decreasing fat utilization. We hypothesized that impaired ghrelin secretion in anorexia nervosa may be involved in the pathogenesis of this eating disorder. To examine this hypothesis and to further investigate the role for ghrelin in regulating energy homeostasis, we analyzed circulating ghrelin levels in patients with anorexia nervosa and examined possible correlations with clinical parameters before and after weight gain.

METHODS

Plasma ghrelin levels were measured in overnight fasting plasma samples from 36 female patients with anorexia nervosa (age: 25.0+/-1.2 years, BMI: 15.2+/-0.2 kg/m(2)) before and after weight gain following psychotherapeutic treatment intervention in a psychosomatic institution. Plasma ghrelin levels were also measured in fasting plasma samples from 24 age-matched female controls (31+/-1.4 years, BMI: 22.9+/-0.45 kg/m(2)). For quantification of ghrelin levels a commercially available radioimmunoassay (Phoenix Pharmaceuticals, USA) was used.

RESULTS

Fasting plasma ghrelin levels in anorectic patients were significantly higher (1057+/-95 pg/ml) than in normal age-matched female controls (514+/-63 pg/ml n=24, P=0.02). Therapeutic intervention in a psychosomatic institution caused an BMI increase of 14% (P<0.001) leading to a significant decrease in circulating ghrelin levels of 25%, (P=0.001). A significant negative correlation between Deltaghrelin and DeltaBMI was observed (correlation coefficient: -0.47, P=0.005, n=36).

CONCLUSION

We show for the first time that fasting plasma levels of the novel appetite-modulating hormone ghrelin are elevated in anorexia nervosa and return to normal levels after partial weight recovery. These observations suggest the possible existence of ghrelin resistance in cachectic states such as caused by eating disorders. Future studies are necessary to investigate putative mechanisms of ghrelin resistance such as a possible impairment of intracellular ghrelin receptor signaling in pathophysiological states presenting with cachexia.

MICA, MICB and C1_4_1 polymorphism in Crohn's disease and ulcerative colitis

MICA and MICB belong to a multicopy gene family located in the major histocompatibility complex (MHC) class I region near the HLA-B gene. They encode for MHC class I molecules, which are induced by stress factors like infection, heat shock or neoplastic transformation and which are mainly expressed on gastrointestinal epithelium. They are recognized by gammadelta T lymphocytes and natural killer (NK) cells. Additionally they are located within a linkage region on chromosome 6p around HLA-B and TNFalpha. Thus the polymorphic MICA and MICB genes are excellent candidate genes for providing the genetic background of inflammatory bowel disease. A strong association of allele A6 of the MICA exon 5 trinucleotide microsatellite polymorphism with ulcerative colitis has been found in Japanese patients. Therefore, we have analysed the MICA exon 5 polymorphism, the MICB intron 1 dinucleotide polymorphism and in addition the tetranucleotide polymorphism C1_4_1, which is located between the MICA gene and the HLA-B gene, in patients of Caucasoid origin with Crohn's disease (n=94) and ulcerative colitis (n=94). In this study we could not find any associations of particular alleles of the MICA, MICB and C1_4_1 polymorphisms with Crohn's disease or ulcerative colitis. We could also not discover any associations of specific two-point or three-point haplotypes with these diseases. Thus it is unlikely that the MICA and MICB genes are involved in causing susceptibility for inflammatory bowel disease, although it cannot be excluded that a weak association could be identified in a larger patient sample.

K-ras and p53 mutations in colonic lavage fluid of patients with colorectal neoplasias

BACKGROUND

The adenoma-carcinoma sequence has its molecular basis in several gene mutations of which K-ras and p53 are of paramount importance. The aims of this study were to evaluate whether these genetic alterations can be detected in colonic lavage fluid from patients with colorectal adenomas and carcinomas.

METHODS

In 45 patients with adenomas, 20 patients with colorectal carcinomas and 38 patients with non-neoplastic and noninflammatory diseases of the colon p53 and K-ras mutations were evaluated in colonic lavage fluid employing single-strand confirmation polymorphism analysis and dot-blot hybridization, respectively.

RESULTS

Mutations of the K-ras and the p53 gene were found in 15.6% (p = 0.065) of patients with adenomas, in 25.0 % (p = 0.016) of patients with carcinomas and in 2.6% in the control group.

CONCLUSION

Genetic alterations in the colonic lavage fluid could be an additional diagnostic tool for the surveillance of patients with colorectal neoplasias.

Interleukin-4 and interleukin-4 receptor gene polymorphisms in inflammatory bowel diseases

Imbalances in the regulation of Th1 and Th2 lymphocytes are crucial in inflammatory bowel diseases. Interleukin-4 is secreted by Th2 lymphocytes and downregulates cytokine production from Th1 lymphocytes. Functionally relevant polymorphisms have been described in the interleukin-4 and the interleukin-4 receptor alpha genes. Association of inflammatory bowel diseases with these polymorphisms has been reported recently suggesting high transcription and enhanced signalling activity in Crohn's disease. Our study, comprising 211 patients with Crohn's disease, 147 patients with ulcerative colitis and 446 healthy controls revealed significant association of Crohn's disease with the -590 T allele of the interleukin-4 gene (P = 0.03). This allele entails reduced expression of IL-4. The reason for these contrasting findings may be discussed in the context of a putatively predisposing allele in linkage disequilibrium with the alleles of the interleukin-4 gene.

The IL-10 gene is not involved in the predisposition to inflammatory bowel disease

Although genetic predisposition for inflammatory bowel disease (IBD) is well established, little is known about the accountable genes. The pathogenesis of IBD is characterized by an imbalanced activation of Th1- and Th2-lymphocytes. IL-10 represents an anti-inflammatory cytokine which downregulates the production of Th1-derived cytokines. To evaluate the role of the IL-10 gene in IBD, two polymorphisms in the promoter region (G/A at position -1082 and C/A at position -592) were genotyped in 142 patients with Crohn's disease (CD), 104 patients with ulcerative colitis (UC), and 400 healthy controls. Significant differences were not apparent, neither in the allele frequencies of either polymorphism, nor in the haplotype frequencies. Screening of the coding region of the IL-10 gene by polymerase chain reaction--single strand conformation polymorphism (PCR-SSCP) analysis revealed a rare sequence variation in exon 1 leading to an amino acid exchange (G-->A; G15R) in two patients with CD and five healthy controls. Therefore, polymorphisms of the IL-10 gene are not demonstrably involved in the predisposition of IBD in our cohorts of patients.

Post-prandial decrease of circulating human ghrelin levels

Ghrelin, an endogenous ligand of the GH secretagogue-receptor, has recently been shown to stimulate GH secretion and to have orexigenic and adipogenic effects in rodents, but little is known about its regulation and biological function in humans. Gastric motor function is under control of the central nervous system; however, the afferent and efferent loops of this feedback control mechanism remain to be elucidated. In the study presented here we investigated the effect of nutrient intake on circulating human ghrelin levels, and a possible association between ghrelin levels and gastric emptying. Ten healthy volunteers received a standard meal after an overnight fast. Food intake significantly decreased plasma ghrelin levels from 248.5 +/- 15.0 to 179.5 +/- 17.9 fmol/ml (120 min after meal, p=0.047). Gastric emptying half-time (non-invasive 13C-octanoic acid breath test) was correlated with fasting plasma ghrelin levels (r=0.74, p=0.0013). Ghrelin appears to be one possible candidate to provide feedback signaling between nutrient intake, gastric motor function and the central nervous system.