This study involved 175 patients with definite IE according to modified Duke Criteria for diagnosis of IE from 3/2005 till 6/2008 from the IE database of cardiology department at Cairo University Hospital, and 175 control cases with same age and sex. Control cases were collected on base of maximum available matching to IE cases in term of: age, gender, and major etiological confounding factors such as underlying known heart disease, prosthetic valves, congenital heart disease and others not known to have one of the these diseases (normal valve). The significance level used in univariate analysis was p <0.05. Multiple comparisons were adjusted for using the Bonferroni correction.