ABSTRACT
BACKGROUND: The urea breath test (UBT) is generally considered the gold standard for the diagnosis of Helicobacter pylori infections in adults. GOALS: To investigate the utility and accuracy of urea breath testing in children from the United States. METHODS: Children scheduled to undergo upper gastrointestinal endoscopy for various clinical symptoms underwent a 13C-UBT using the US standard protocol for adults. Results were compared with rapid urease testing (RUT), culture, and histology. H. pylori positivity was defined according to the FDA, Division of Anti-Infective Drug Products criteria, i.e. positive culture and/or positive RUT and histology. H. pylori negativity was defined as all tests negative. Results were evaluated by delta over baseline (DOB) and urea hydrolysis rate (UHR). RESULTS: A total of 176 children from five centers were evaluated; 48 were infected. Compared to the defined standard, the results with the UBT based on delta over baseline (DOB) cut-off value (positive: > or = 2.4 per thousand) showed that the sensitivity and specificity of the UBT were 97.9% and 96.1%, respectively. Based on the UHR cut-off value (positive: > or = 10.0 microg/min), the sensitivity and specificity were 95.8% and 99.2%. In young children (2- to 5-year olds), sensitivity and specificity of UHR method were higher than the DOB method (100% and 100% vs 100% and 82.4%, respectively). CONCLUSION: The US standard (13)C-UBT proved to be both simple and accurate for the diagnosis of H. pylori infections in children. The UHR method to calculate of (13)C-UBT result provided excellent results for children of all ages.
Subject(s)
Breath Tests/methods , Helicobacter Infections/diagnosis , Adolescent , Carbon Isotopes/metabolism , Child , Child, Preschool , Female , Helicobacter pylori/isolation & purification , Helicobacter pylori/metabolism , Humans , Male , Prospective Studies , United States , Urea/metabolismSubject(s)
Amino Acid Metabolism, Inborn Errors/complications , Argininosuccinic Acid/urine , Hyperammonemia/diagnosis , Liver Cirrhosis/therapy , Liver Transplantation/methods , Arginine/therapeutic use , Follow-Up Studies , Humans , Hyperammonemia/therapy , Infant , Liver Cirrhosis/etiology , MaleABSTRACT
BACKGROUND: Polymorphisms in several genes (NOD2, MDR1, SLC22A4) have been associated with susceptibility to Crohn's disease. Identification of the remaining Crohn's susceptibility genes is essential for the development of disease-specific targets for immunotherapy. Using gene expression analysis, we identified a differentially expressed gene on 5q33, the colony stimulating factor 1 receptor (CSF1R) gene, and hypothesized that it is a Crohn's susceptibility gene. The CSF1R gene is involved in monocyte to macrophage differentiation and in innate immunity. METHODS: Patients provided informed consent prior to entry into the study as approved by the Institutional Review Board at LSU Health Sciences Center. We performed forward and reverse sequencing of genomic DNA from 111 unrelated patients with Crohn's disease and 108 controls. We also stained paraffin-embedded, ileal and colonic tissue sections from patients with Crohn's disease and controls with a polyclonal antibody raised against the human CSF1R protein. RESULTS: A single nucleotide polymorphism (A2033T) near a Runx1 binding site in the eleventh intron of the colony stimulating factor 1 receptor was identified. The T allele of this single nucleotide polymorphism occurred in 27% of patients with Crohn's disease but in only 13% of controls (X2 = 6.74, p < 0.01, odds ratio (O.R.) = 2.49, 1.23 < O.R. < 5.01). Using immunohistochemistry, positive staining with a polyclonal antibody to CSF1R was observed in the superficial epithelium of ileal and colonic tissue sections. CONCLUSIONS: We conclude that the colony stimulating factor receptor 1 gene may be a susceptibility gene for Crohn's disease.
