Celiac disease: the new proposed ESPGHAN diagnostic criteria do work well in a selected population.

BACKGROUND: The need for an early and accurate diagnosis in celiac disease (CD) has focused attention on new diagnostic approaches, based on the efficiency of serological markers and the high negative predictive value of human leukocyte antigen (HLA) non-DQ2/8. METHODS: We performed a retrospective review of all of the patients suspected of having CD who had undergone a small bowel biopsy in our gastroenterology unit. All symptomatic children with serological marker at time of biopsy (immunoglobulin A-tissue transglutaminase antibody, endomysial antibody, and HLA genotype) were included. The triple test (TT) was positive if immunoglobulin A-tissue transglutaminase antibody was 10 times the upper limit of normal, plus positive endomysial antibody plus human leukocyte antigen-DQ2/DQ8. RESULTS: A total of 150 patients met the inclusion criteria and were enrolled in the study. One hundred sixteen were positive for the TT; 113 of 116 (97.4%) had a Marsh 2/3 histological lesion and had been considered to have CD. Thus, positive predictive value of the TT was 97.4%. The other 3 cases (2.6%) had Marsh 0/1 lesion, so we consider them to be false-positives for the TT; however, on follow-up, all 3 children developed histological damage after a gluten challenge. Finally, the positive predictive value of the TT was 100%. Thirty-four patients were negative for the TT: 22 patients are celiac, 3 are celiac but challenge gluten diet is pending, and the 9 patients left have other gastrointestinal disorder. CONCLUSIONS: Our study supports the view that in selected children who are symptomatic and positive for the TT, CD diagnosis could be established independent of histological findings.

Lactulose hydrogen breath test and functional symptoms in pediatric patients.

BACKGROUND: The role of small intestinal bacterial overgrowth (SIBO) in functional digestive disorders in the pediatric population is a matter of controversy, since methods currently used to establish this diagnosis are difficult to interpret. The aim of this work was to analyze the characteristics of the lactulose H(2) breath test (LHBT) in children with functional gastrointestinal symptoms according to more recent criteria. METHODS: Seventy-two patients and 17 controls were enrolled. A questionnaire was administered regarding digestive symptoms (abdominal pain, bloating, vomiting, and bowel-movement disorders). A lactose hydrogen breath test was performed to rule out lactose malabsorption and a LHBT was used to measure the time elapsed between lactulose oral ingestion and an increment of H(2) concentration of 20 ppm over basal. RESULTS: There were no differences of age and gender between patients and controls. Mean time to 20-ppm change was shorter in patients (56.3 ± 3 min) compared to healthy children (74.7 ± 5 min), p\0.05. In 39% of patients, rise of H(2) occurred during the first 40 min after lactulose ingestion, and in almost all controls, an increment was observed between 50 and 90 min (p\0.05). Symptoms were unrelated to time to 20-ppm change. CONCLUSIONS: An abnormal LHBT was found in children with functional symptoms of the digestive tract, but the exact mechanism involved, accelerated intestinal transit or SIBO, needs to be confirmed by an additional method.

Relationship between Helicobacter pylori virulence factors and regulatory cytokines as predictors of clinical outcome.

Helicobacter pylori infection is highly prevalent in Chile (73%). Usually a minority of infected patients develops complications such as ulcers and gastric cancer that have been associated with the presence of virulence factors (cagA, vacA) and host T helper response (Th1/Th2). Our aim was to evaluate the relationship between strain virulence and host immune response, using a multiple regression approach for the development of a model based on data collected from H. pylori infected patients in Chile. We analyzed levels of selected cytokines determined by ELISA (interleukin (IL)-12, IL-10, interferon (IFN)-gamma and IL-4) and the presence of cagA and vacA alleles polymorphisms determined by PCR in antral biopsies of 41 patients referred to endoscopy. By multiple regression analysis we established a correlation between bacterial and host factors using clinical outcome (gastritis and duodenal ulcer) as dependent variables. The selected model was described by: clinical outcome=0.867491 (cagA)+0.0131847 (IL-12/IL-10)+0.0103503 (IFN-gamma/IL-4) and it was able to explain over 90% of clinical outcomes observations (R(2)=96.4). This model considers that clinical outcomes are better explained by the interaction of host immune factors and strain virulence as a complex and interdependent mechanism.