Possible relationship between Helicobacter pylori cagA gene and development of idiopathic thrombocytopenic purpura

Abstract

ABSTRACT Helicobacter pylori (H.pylori) is a gram-negative bacterium that is related to the development of gastric and extragastric diseases. Gastric diseases include gastric cancer, chronic gastritis, peptic ulcer and MALT lymphoma. Extragastric diseases include iron deficiency anemia and some auto-immune conditions such as reumathoid arthritis and idiopathic thrombocytopenic purpura. PCR has been an important tool for the analysis of small fragments of DNA that may be stored for a longer time inserted in paraffin blocks or fresh tissue at 80ºC. Hare we studied 45 patients with ITP and 33 of these ones had positive tests, with agreement of 100% of histological and rapid urease test. Besides the primers for H.pylori detection primers for urease C region and cagA gene were used and the fragments obtained were analysed in agarose gel by ultraviolet radiation. We obtained 100% of agreement for urease C region and detection of H.pylori and 30% of agreement for cagA gene. In these 33 patients which were H.pylori positive, 27,7% had complete remission, 33,0 partial remission and 40% had no remission. In positive patients for cagA gene, 9,0% had complete remission and 21,2% had no remission. In negative patients for cagA gene 21,2% had complete remission and 48,4% had no remission. We used statistical analysis (Exact Fishers test, Box-plot and Mann- Withney) to relations cagA gene and thrombocytopenic idiopathic purpura, our results don´t suggest or correlate the presence of cagA gene with idiopathic thrombocytopenic purpura development.

Keywords

• Gene cagA
• Purpura
• Helicobacter pylori