RESUMEN
This study was conducted on 112 children with congenital heart diseases [CHD] [53 cyanotic and 59 acyanotic] attending Cairo University Children's Hospital [CUCH], cardiology outpatient clinic. They were taken over a period of 8 months. Fifty-nine asthmatics were also included, they were recruited from the chest clinic [CUCH,] during the same period. One hundred normal controls were taken from the well-baby clinic Al-Azhar University. All infants and children studied were 6 to 36 months of age. The aim of the study was to estimate the sero-prevalence of Helicobacter pylon in children with CHD and comparing them to another group of sick children like asthmatics then versus normal controls. 28.2% of the whole number of children studied [171] were sero-positive. The 100 normal controls showed 18% sero-positiveness for Helicobacter pylari. 32.1% of the cyanotic group were sero-positive compared to 18.6%of the acyanotics. Asthmatics scored 35.6%. There was a highly positive correlation between age and Helicobacter pylon infection. We concluded that Helicobacter pylon infection showed high prevalence in chronically ill children. It has to be considered as a risk for development of ulcer disease in CHD especially that these children may eventually undergo surgery, which is another risk factor for peptic ulcers. Those children may also need anticoagulation in the post-operanve period