Current concept on the pathogenesis of inflammatory bowel disease-crosstalk between genetic and microbial factors:Pathogenic bacteria and altered bacterial sensing or changes in mucosal integrity take"toll"?

The pathogenesis of inflammatory bowel disease （IBD） is only partially understood. Various environmental and host （e.g. genetic-, epithelial-, immune and nonimmune） factors are involved. It is a multifactorial polygenic disease with probable genetic heterogeneity. Some genes are associated with IBD itself, while others increase the risk of ulcerative colitis （UC） or Crohn＇ s disease （CD） or are associated with disease location and/or behaviour. This review addresses recent advances in the genetics of IBD. The article discusses the current information on the crosstalk between microbial and genetic factors （e.g. NOD2/CARD15, SLC22A46A5 and DLG5）. The genetic data acquired in recent years help in understanding the pathogenesis of IBD and can identify a number of potential targets for therapeutic intervention. In the future, genetics may help more accurately diagnose and predict disease course in IBD.

Perianal disease,small bowel disease,smoking,prior steroid or early azathioprine/biological therapy are predictors of disease behavior change in patients with Crohn's disease

AIM:To assess the combined effect of disease phenotype, smoking and medical therapy [steroid, azathioprine(AZA), AZA/biological therapy] on the probability of disease behavior change in a Caucasian cohort of patients with Crohn's disease(CD).METHODS:Three hundred and forty well-characterized, unrelated, consecutive CD patients were analyzed(M/F:155/185, duration:9.4 ± 7.5 years) with a complete clinical follow-up.Medical records including disease phenotype according to the Montreal classification, extraintestinal manifestations, use of medications and surgical events were analyzed retrospectively.Patients were interviewed on their smoking habits at the time of diagnosis and during the regular follow-up visits.RESULTS:A change in disease behavior was observed in 30.8% of patients with an initially non-stricturing, non-penetrating disease behavior after a mean diseaseduration of 9.0 ± 7.2 years.In a logistic regression analysis corrected for disease duration, perianal disease, smoking, steroid use, early AZA or AZA/ biological therapy use were independent predictors of disease behavior change.In a subsequent Kaplan-Meier survival analysis and a proportional Cox regression analysis, disease location(P = 0.001), presence of perianal disease(P < 0.001), prior steroid use(P = 0.006), early AZA(P = 0.005) or AZA/biological therapy(P = 0.002), or smoking(P = 0.032) were independent predictors of disease behavior change.CONCLUSION:Our data suggest that perianal disease, small bowel disease, smoking, prior steroid use, early AZA or AZA/biological therapy are all predictors of disease behavior change in CD patients.

Toll-like receptor 4 and NOD2/CARD15 mutations in Hungarian patients with Crohn's disease: Phenotype-genotype correlations

AIM: To determine common NOD2/CARD15 mutations and TLR4 D299G polymorphism in Hungarian patients with CD. METHODS: A total of 527 unrelated patients with CD (male/female: 265/262, age: 37.1 (SD 7.6) years) and 200 healthy subjects were included. DNA was screened for possible NOD2/CARD15 mutations by denaturing high-performance liquid chromatography (confirmed by direct sequencing). TLR4 D299G was tested by PCR-RFLP. RESULTS: NOD2/CARD15 mutations were found in 185 patients (35.1%) and in 33 controls (16.5%,P<0.0001). SNP8/R702W (10.8% vs 6%, P= 0.02), SNP13/3020insC (19.4% vs 5%, P<0.0001) and exon4 R703C (2.1% vs 0%, P= 0.02) mutations were more frequent in CD, while the frequency of SNP12/G908R was not increased. The frequency of TLR4 D299G was not different (CD: 9.9% vs controls: 12.0%). Variant NOD2/CARD15 allele was associated with an increased risk for CD (ORhet=1.71, 95%CI=1.12-2.6, P= 0.0001, ORtwo-risk alleles = 25.2, 95%CI =4.37- ,P<0.0001), early disease onset (carrier: 26.4 years vs non-carrier: 29.8 years, P=0.0006), ileal disease (81.9% (?) 69.5%, OR = 1.99, 95%CI = 1.29-3.08, P= 0.02, presence of NOD2/CARD15 and TLR4: 86.7% vs 64.8%), stricturing behavior (OR = 1.69,95%CI = 1.13-2.55, P= 0.026) and increased need for resection (OR=1.71, 95%CI: 1.13-2.62, P= 0.01), but not with duration, extra-intestinal manifestations, familial disease or smoking. TLR4 exhibited a modifier effect: age of onset in wt/TLR4 D299G carriers: 27.4 years vs NOD2mut/TLR D299G: 23 years (P = 0.06), in NOD2mut/wt: 26.7 years. CONCLUSION: These results confirm that variant NOD2/ CARD15 (R702W, R703C and 3020insC) alleles are associated with earlier disease onset, ileal disease, stricturing disease behavior in Hungarian CD patients. In contrast, although the frequency of TLR4 D299G polymorphism was not different from controls, NOD2/TLR4 mutation carriers tended to present at earlier age.

Germline MLH1 and MSH2 mutational spectrum including frequent large genomic aberrations in Hungarian hereditary non-polyposis colorectal cancer families:Implications for genetic testing

AIM: To analyze the prevalence of germline MLH1 and MSH2 gene mutations and evaluate the clinical characteristics of Hungarian hereditary non-polyposis colorectal cancer (HNPCC) families. METHODS: Thirty-six kindreds were tested for mutations using conformation sensitive gel electrophoreses, direct sequencing and also screening for genomic rearrangements applying multiplex ligation-dependent probe amplifi cation (MLPA). RESULTS: Eighteen germline mutations (50%) were identifi ed, 9 in MLH1 and 9 in MSH2. Sixteen of these sequence alterations were considered pathogenic, the remaining two were non-conservative missense alterations occurring at highly conserved functional motifs. The majority of the defi nite pathogenic mutations (81%, 13/16) were found in families fulfilling the stringent Amsterdam Ⅰ/Ⅱ criteria, including three rearrangements revealed by MLPA (two in MSH2 and one in MLH1). However, in three out of sixteen HNPCC-suspected families (19%), a disease-causing alteration could be revealed. Furthermore, nine mutations described here are novel, and none of the sequence changes were found in more than one family.CONCLUSION: Our study describes for the f irst time the prevalence and spectrum of germline mismatch repair gene mutations in Hungarian HNPCC and suspected-HNPCC families. The results presented here suggest that clinical selection criteria should be relaxed and detection of genomic rearrangements should be included in genetic screening in this population.

Mucocele of the appendix: An unusual cause of lower abdominal pain in a patient with ulcerative colitis-. A case report and review of literature

The authors report the case of a 60-year-old male patient. In November 2001 he developed intestinal symptoms of bloody diarrhea and abdominal pain. Colononoscopy and biopsy established the diagnosis of ulcerative colitis (proctosigmoiditis). The disease activity was moderate at the beginning. No significant laboratory alterations were found (including CEA, CA19-9), and mesalazine was started orally. He was in remission until November 2003, when he was admitted to our Outpatient Clinic for upper and right lower abdominal pain and bloody diarrhea. Colonoscopy found proctosigmoiditis with a moderate activity, gastroscopy revealed chronic gastritis, laboratory data was normal. Treatment was amended with mesalazine clysma and methylprednisolone (16 mg) orally. Symptoms ameliorated; however, right lower abdominal pain persisted. US and CT examinat'on demonstrated a pericecal cystic mass (11 cm×3.5 cm). At first pericecal abscess was suspected, as the previous US examination (6 mo earlier) had revealed normal findings. Fine needie aspiration was performed. Cytology confirmed the diagnosis of mucocele. The patientunderwent partial cecum resection and extirpation of the mucocele. He recovered well and the final histology revealed a cystadenoma of the appendix. Follow up was started. The pati雗t is now free of symptoms. Although primary adenocarcinoma of the appendix is uncommon, the authors emphasize that preoperative diagnosis of an underlying malignancy in a mucocele is important for pati雗t management; however, it is difficult on imaging studies.

NKX2-3 and IRGM variants are associated with diseasesu sceptibility to IBD in Eastern European patients

AIM: To investigate variants of immunity-related GT-Pase family M (IRGM) and NKX2-3 genes and genotype-phenotype in Eastern European patients with inflammatory bowel disease (IBD).METHODS: We analyzed 1707 Hungarian and Czech subjects with Crohn’s disease (CD) (n = 810, age: 37.1 ± 12.6 years, duration: 10.7 ± 8.4 years) and ulcerative colitis (UC) (n = 428, age: 43.7 ± 15.0 years, duration: 12.6 ± 9.9 years), as well as 469 healthy controls. IRGM rs13361189, NKX2-3 rs10883365 and ECM1 rs13294 polymorphisms were tested by LightCy-cler allele discrimination. Detailed clinical phenotypes were determined by reviewing the medical charts. RESULTS: NKX2-3 rs10883365 variant allele was as-sociated with increased risk for CD (P = 0.009, OR = 1.24, 95% CI = 1.06-1.48) and UC (P = 0.001, OR = 1.36, 95% CI = 1.13-1.63), whereas variant IRGM allele increased risk for CD (P = 0.029, OR = 1.36, 95% CI = 1.03-1.79). In contrast, ECM1 rs13294 was not associat-ed with either CD or UC. In CD, the variant IRGM allele was associated with a colon-only location (P = 0.02, OR = 1.62, 95% CI = 1.07-2.44), whereas in UC, the ECM1 variant was associated with cutaneous manifestations (P = 0.002, OR = 3.36, 95% CI = 1.48-7.63). Variant alleles did not predict resistance to steroids or azathio-prine, efficacy of infliximab, or need for surgery. CONCLUSION: NKX2-3 and IRGM are susceptibility locifor IBD in Eastern European patients. Further studies are needed to confirm the reported phenotype-genotype associations.

Double balloon enteroscopy examinations in general anesthesia

AIM:To demonstrate that the double balloon enteroscopy(DBE) can be safely performed in general anesthesia with intubation.METHODS:We performed a retrospective examination between August 2005 and November 2008 amongpatients receiving intubation narcosis due to DBE examination.The patients were grouped based on sex,age and physical status.Anesthesia records includedduration of anesthesia,quantity of medication usedand anesthesia-related complications.We determinedthe frequency of complications in the different groupsand their relation with the quantity of medication usedand the duration of anesthesia.RESULTS:We compiled data for 108 cases of general anesthesia with intubation.We did not observeany permanent anesthesia-related complications;themost frequent side effects of anesthesia were hypo-tension(30.55%),desaturation(21.29%),and apnea(17.59%).These complications were significantly more frequent among patients with multiple additional diseases [hypotension(23.1% vs 76.9%,P = 0.005),desaturation(12.3% vs 69.2%,P < 0.001) and apnea(7.7% vs 53.8%,P = 0.001)],however,their incidence was not proportional to the quantity of medication used or the duration of anesthesia.CONCLUSION:General anesthesia with intubation is definitely a viable option among DBE methods.It is highly recommended in patients with multiple additional diseases.