Immunodetection of Helicobacter sp. and the associated expression of ABO blood group antigens in the gastric mucosa of captive and free-living New World primates in the Amazon region

The histo-blood group ABH antigens were first described in humans. These antigens are only present on erythrocytes from great apes and humans, while in more primitive animals they are found in tissues and body fluids. The ABH antigens are mainly distributed in tissues exposed to the external environment and potentially serve as ligands for pathogens or inhibitors of tissue connections. The objective of this paper was two-fold: (i) to determine the presence of Helicobacter sp. in the gastric mucosa of 16 captive and 24 free-living New World monkeys and (ii) to evaluate the presence of histopathological alterations related to bacterial infection and the associated expression of ABH antigens in the tissue. Stomach tissues from 13 species of monkey were assessed using haematoxylin-eosin and modified Gram staining (Hucker) methods. An immunohistochemical analysis of the tissue revealed the presence of infectious bacteria that were characteristic of the genus Helicobacter sp. The results demonstrate that various species of monkey might be naturally infected with the Helicobacter sp. and that there is an increased susceptibility to infection. This study serves as a comparative analysis of infection between human and non-human primates and indicates the presence of a new species of Helicobacter.

[Diagnostic accuracy of helicobacter stool antigen in dyspeptic patients before eradication therapy]

The aim of this study was to assess and compare the diagnostic accuracy of Helicobacter pylori stool antigen [HpSA] test with three other invasive and non-invasive diagnostic methods. A total of Fifty-two dyspeptic patients were included. None of the patients had previous eradication therapy for Helicobacter pylori. Endoscopic biopsy samples were obtained for histology examination and Rapid Urease Test [RUT]. Urea Breath Test [UBT] and HpSA were also performed. Patients were considered Helicobacter pylori positive when 2 of 3 tests [histology examination, RUT and UBT] were positive [gold standard]. Diagnostic accuracy of HpSA was assessed performing a Receiver Operating Curve [ROC] analysis. Twenty-three Were men and 29 Were women, with a mean age of 42.3 years of the Patients. The prevalence of Helicobacter pylori infection was 67.3%. ROC curve analysis was showed a significant area under curve of 94.6% [p=0.0001]. Cut-off value was estimated to be 0.1. The sensitivity, specificity, positive and negative predictive values of HpSA wa 91.4%, 94.1%, 97% and 84%, respectively. HpSA level significantly increased with increasing in bacterial load. HpSA was proved to be a highly accurate, simple and non-invasive test for the diagnosis of Helicobater pylori infection before treatment in dyspeptic patients

Crecimiento y evolución del Helicobacter pylori / Growth and evolution of Helicobacter pylori

El género Helicobacter tiene una historia relativamente reciente. Su protagonismo data del año 1982, fecha en la que el Helicobacter Pylori se aisló por primera vez de paciente humanos. Esta bacteria, inicialmente, se incluyó en el género Campylobacter y se la denominó Campylobacter Pylori o Piloridis. Posteriormente en el año 1989, se separo de este género y se creó uno nuevo el género Helycobacter, al que actualmente pertenecen varias especies. Los expertos en microbiología le asignaron este término por su forma de hélice in vivo y sus caracteres de bacteria in vitro, ya que encontraron que la denominación Campylobacter era errónea en vista del contenido de ácidos grasos de su pared y por el análisis del ADN se dieron cuenta que la bacteria no pertenecía a los Campylobacter.