Capillaria hepatica in rats: focal parasitic hepatic lesions and septal fibrosis run independent courses

Capillaria hepatica causes two main lesions in the liver of rats: multifocal chronic inflammation, directly related to the presence of disintegrating parasites and their eggs, and a process of systematized septal fibrosis. The comparative behavior of these two lesions was investigated in rats experimentally infected with 600 embryonated eggs, following either corticosteroid treatment or specific antigenic stimulation, in an attempt to understand the relationship between these two lesions, and the pathogenesis of septal fibrosis. The two treatments differently modified the morphological aspects of the focal parasitic-related lesions, but did not interfere with the presentation of diffuse septal fibrosis, although a mild decrease in the degree of fibrosis occurred in corticoid-treated animals. These findings indicate that although the two lesions are C. hepatica induced, they are under different pathogenetic control, the induction of septal fibrosis being triggered during early infection to follow an independent pathway.

Urea breath test for the detection of Helicobacter pylori using a stable isotope (13C)

O H. pylori está presente no estômago da maioria dos pacientes portadores de úlcera duodenal. Para seu diagnóstico são utilizados: técnicas de histopatologia, o teste da urease e testes respiratórios (UBT) com uréia marcada com o isótopo radioativo (14C) ou do estável (13C). Este trabalho teve por objetivos: 1) realizar o UBT como procedimento diagnóstico da presença de H. pylori utilizando isótopo estável; 2) comparar os resultados com os obtidos por meio da urease, histologia (considerados padrão-ouro) e UBT com 14C-uréia. Foram avaliados 54 pacientes com idades entre 30 e 55 anos, sendo 25 mulheres. O UBT apresentou sensibilidade e especificidade 90 por cento (Kappa entre 0,77 e 1,03). Níveis de detecção, aos 30 minutos, menores que 4,82delta por cento foram considerados negativos. Entre 4,82 e 14,96delta por cento, duvidosos, recomendando repetir o teste, e acima deste valor, positivos. Neste estudo, o UBT com 13C-uréia foi prático, adequado, de fácil execução e inócuo, recomendando este procedimento diagnóstico na suspeita da presença do H. pylori em adultos e crianças, independente do sexo ou condição fisiopatológica.

Accuracy of the 14C-urea breath test for the diagnosis of Helicobacter pylori

CONTEXT: The development of simple, accurate and low-expense techniques for detection of Helicobacter pylori infection has great relevance. OBJECTIVE: To determine the accuracy of a rapid 14C-urea breath test (UBT) employing a very simple device for breathed air collection. DESIGN: Prospective study. SETTING: Hospital das Clinicas of the Faculty of Medicine of Ribeiräo Preto. PARTICIPANTS: One hundred and thirty-seven adult patients who underwent upper gastrointestinal endoscopy in the Clinical Hospital. MAIN MEASUREMENTS: Histology for Helicobacter pylori (HP); urease test; urea breath test (UBT). RESULTS: One hundred and fifteen patients were infected by HP (HP+) according to both histology and the urease test, and 22 patients were HP-negative (HP-), according to the same two tests. UBT was capable of discriminating between HP+ and HP- in a way that was similar to the combination of urease test and histology. When this combination of results is taken as the "gold standard" for HP infection, the sensitivity and specificity of UBT are both greater than 90 percent for a range of cut-off points and breathed air collection times. CONCLUSION: The rapid UBT employing a simple device for air collection has a high accuracy in determining HP infection