ABSTRACT
BACKGROUND: The urea breath test (UBT) with a microdose of [14C] is a non-invasive and simple method for the assessment of gastric infection by Helicobacter pylori. The aim of this study was to compare the [14C]UBT with invasive methods widely used for assessment of H. pylori gastric infection, including histology with hematoxylin-eosin staining, the gastric smear technique using Giemsa staining, and the biopsy urease test. MATERIAL/METHODS: We evaluated patients referred to our clinic for elective upper gastrointestinal endoscopy excluding those on antibiotics and/or bismuth during the previous 4 weeks, patients on H+ blockers or H2 antihistamines during the previous 7 days, pregnant women, and patients who had undergone gastric surgery or had bleeding disorders. Eighty-nine patients ranging in age from 18-75 years were included in the final study population, 61 women and 28 men (mean age: 43(15 years). RESULTS: When histology alone was considered as the reference standard, sensitivity for the [14 C]UBT was 94%, with a specificity of 37%; when the Giemsa technique, sensitivity was 95%, and specificity 35%; and when the biopsy urease test, sensitivity was 94% and specificity 45%. With two or more invasive techniques together considered as the reference standard, the [14C]UBT had a sensitivity of 95%, with a specificity of 44%. CONCLUSIONS: [14C]UBT is an objective and reproducible technique, capable of sampling the whole gastric mucosa. It shows high sensitivity, but low specificity, which could be explained by limited gastric sampling plus subjective interpretation in the invasive techniques that are currently used as gold standard.
Subject(s)
Breath Tests/methods , Carbon Radioisotopes , Helicobacter Infections/diagnosis , Helicobacter pylori/metabolism , Urea/metabolism , False Positive Reactions , Female , Humans , Male , Pregnancy , Reference Standards , Reproducibility of Results , Sensitivity and Specificity , Statistics as Topic , Urea/chemistryABSTRACT
BACKGROUND: Infection with Helicobacter pylori is frequent in Chile, and a good test for its diagnosis ideally should be non-invasive, fast, easy and inexpensive. AIM: To report the use of an immunoassay test, that detects antigens of Helicobacter pylori in stools. MATERIAL AND METHODS: One hundred and four patients that required an upper gastrointestinal endoscopy were studied. Stool samples were analyzed using an enzymatic immunoassay. These results were compared with those obtained with the urease test and microscopic examination of smears taken from biopsies obtained during the diagnostic endoscopy. RESULTS: In 81 of 83 patients considered to have the infection according to the endoscopic tests, the antigen was also present in the stools. The test was negative in 16 of 21 patients considered to be without the infection. The resulting sensitivity and specificity for the immunoassay was thus 97.6 and 76.2% respectively, with positive and negative predictive values of 92.4 and 88.9%, respectively. CONCLUSIONS: These results are in agreement with those reported in the literature. Further studies are needed to define its usefulness in massive screening, follow up after antibiotic treatments or the detection of coccoid forms of Helicobacter pylori.
Subject(s)
Antigens, Bacterial/analysis , Enzyme-Linked Immunosorbent Assay , Feces/microbiology , Helicobacter Infections/diagnosis , Helicobacter pylori/immunology , Adolescent , Adult , Aged , Child , Female , Helicobacter Infections/immunology , Helicobacter Infections/microbiology , Helicobacter pylori/isolation & purification , Humans , Male , Middle Aged , Predictive Value of Tests , Sensitivity and Specificity , Urease/analysisABSTRACT
La Asociación Chilena de Hepatología creó un registro de casos nuevos de hepatitis crónicas diagnosticadas con biopsia hepática entre los años 1994 y 1996. Se registran y clasifican de acuerdo a su etiología 106 pacientes altamente seleccionados con hepatitis crónica provenientes de la regiones metropolitana, quinta y segunda. De acuerdo a la etiología: 13 por ciento criptogénicas y 7 por ciento Virus B. La presencia de cirrosis al diagnóstico fue de 30 por ciento para las de origen viral C y 24 por ciento para las de origen autoinmune lo que podría afectar la respuesta a las alternativas terapéuticas. De acuerdo a estos resultados, deberíamos promover el diagnóstico más temprano en pacientes con alteraciones de laboratorio asintomáticas o notificando a los donantes de sangre en los que detecta alguna infección viral. En ausencia de otras instancias que realicen este tipo de evaluaciones, sugerimos repetir o mantener registros en lo posible de cobertura nacional, tanto para los pacientes con hepatitis crónica como para otras patologías hepáticas.
