Semiquantitative assessment of breath hydrogen testing.

BACKGROUND AND AIM: A major use of breath hydrogen testing is to assess absorptive capacity for sugars to assist dietary design for management of gut symptoms. Qualitative reporting takes no account of the vigor of hydrogen response and provides little insight into degrees of malabsorption. This study aimed to describe a semiquantitative reporting method and to compare results with those reported qualitatively. METHODS: In consecutive Caucasian patients with Crohn's disease (n = 87), ulcerative colitis (59), functional gastrointestinal disorders (FGID) (162), and healthy controls (76), area under the curve was calculated for lactulose (15 g). This was compared with that for lactose (50 g) and fructose (35 g). Degree of malabsorption was categorized into arbitrary groups. RESULTS: Semiquantitative results for ≥ 30% (designated "convincing") malabsorption was most similar to those using a qualitative cutoff value of 20 ppm, but in 38% and 21% of patients, the classification of malabsorption (nil or clinically significant) changed for fructose and lactose, respectively. Using a cutoff of 10 ppm, 49% and 5% were classified differently. Crohn's disease had a higher prevalence (42%) of convincing fructose malabsorption than controls (24%) or patients with FGID (33%) (P < 0.02). Highest prevalence of convincing lactose malabsorption (38%) was in ulcerative colitis, greater than controls (18%) and FGID (18%) (P < 0.02). CONCLUSIONS: Semiquantitative assessment provides different results with different clinical implications in more than one third of patients, but disease-related alterations in prevalence are similar to those defined qualitatively. This method may be preferable because it lessens the confounding influence of the vigor of the hydrogen response.

Is a six hour fast after a rice meal sufficient before upper gastrointestinal endoscopy?

OBJECTIVE: Rice is the staple diet in many Asian countries. Current endoscopic guidelines advice a 6 h fast for solids and a 4 h fast for liquids before the procedure. However, these guidelines focus on a Western type diet. The aim of the study was to determine if a 6 h fast for rice is sufficient prior to upper gastrointestinal endoscopy (UGIE). PATIENTS AND METHODS: After informed consent, 212 patients referred for UGIE, who had no alarm symptoms, were randomized into two groups in preparation for UGIE. Fasting 6 h after a rice meal (R6) or fasting 10 h after a rice meal (R10). All meals contained lentils and an egg, and were isocaloric. Endoscopic vision was graded as poor, average, or good. RESULTS: In the R10 group (n = 107) vision was poor in 2 (1.9%), average in 7 (6.5%), and good in 98 (91.6%). While in the R6 group (n = 105) vision was poor in 30 (28.6%), average in 19 (18.1%), good in 56 (53.3%). The observed difference of percentages among the two groups for endoscopic vision was significant (M-H Chi-Square for trend = 25.67; df = 1; p < 0.001). CONCLUSIONS: Fasting for 6 h after a rice based meal seems inadequate for UGIE. Fasting for 10 h significantly improves endoscopic vision. Current guidelines need to be re-evaluated for populations where rice is the staple diet.

Genetic associations of inflammatory bowel disease in a South Asian population.

AIM: To estimate prevalence and phenotypic associations of selected inflammatory bowel disease (IBD)-associated genetic variants among Sri Lankan patients. METHODS: A case study of histologically confirmed ulcerative colitis (UC) or Crohn's disease (CD) patients with ≥ 1 year disease duration, who were compared to unrelated, gender-matched, healthy individuals as controls, was conducted at four major centers in Sri Lanka. Phenotypic data of the cases were obtained and all participants were genotyped for 16 selected genetic variants: IL12B:rs1045431, IL23R:rs11805303, ARPC2:rs12612347, IRGM:rs13361189, IL26/IL22:rs1558744, CDH1:rs1728785, IL10:rs3024505, FCGR2A:rs3737240, PTGER4:rs4613763, IL17REL/PIM3:rs5771069, HNF4a:rs6017342, STAT3:rs744166, SMURF1:rs7809799, LAMB1:rs886774, HLA-DRB5, DQA1, DRB1, DRA:rs9268853, MST1, UBA7, and APEH:rs9822268. The genotypes of all variants were in Hardy-Weinberg Equilibrium (P > 10-3). To account for multiple hypothesis testing, P-values < 0.003 were considered significant. RESULTS: A total of 415 patients and 465 controls were recruited. Out of the single nucleotide polymorphisms (SNPs) tested, the majority were not associated with IBD in Sri Lankans. Significant positive associations were noted between rs886774 (LAMB1-gene) and UC (odds ratio (OR) = 1.42, P = 0.001). UC patients with rs886774 had mild disease (OR = 1.66, P < 0.001) and remained in remission (OR = 1.48, P < 0.001). A positive association was noted between rs10045431 (IL 12B gene) and upper gastrointestinal involvement in CD (OR = 4.76, P = 0.002). CONCLUSION: This confirms the heterogeneity of allelic mutations in South Asians compared to Caucasians. Most SNPs and disease associations reported here have not been described in South Asians.

Prevalence of Acanthosis Nigricans in an urban population in Sri Lanka and its utility to detect metabolic syndrome.

BACKGROUND: Insulin resistance (IR) plays a major role in the pathogenesis of metabolic syndrome. Acanthosis nigricans (AN) is an easily detectable skin condition that is strongly associated with IR. The aims of this study were, firstly, to investigate the prevalence of AN among adults in an urban Sri Lankan community and secondly, to describe its utility to detect metabolic syndrome. FINDINGS: In a community based investigation, 35-64 year adults who were selected using stratified random sampling, underwent interview, clinical examination, liver ultrasound scanning, and biochemical and serological tests. Metabolic syndrome was diagnosed on revised ATP III criteria for Asian populations. AN was identified by the presence of dark, thick, velvety skin in the neck.2957 subjects were included in this analysis. The prevalence of AN, metabolic syndrome and type 2 diabetes mellitus were 17.4%, 34.8% and 19.6%, respectively. There was a strong association between AN and metabolic syndrome. The sensitivity, specificity, positive predictive value and negative predictive value of AN to detect metabolic syndrome were 28.2%, 89.0%, 45.9% and 79.0% for males, and 29.2%, 88.4%, 65.6% and 62.3% for females, respectively. CONCLUSIONS: AN was common in our study population, and although it did not have a high enough sensitivity to be utilized as a screening test for metabolic syndrome, the presence of AN strongly predicts metabolic syndrome.