<prompt> A 46-year-old male , an IV drug abuser presents to OPD with complaints of fatigue, malaise and rigors. His temperature was 38.5degC, pulse -84min, BP- 13080 mm Hg .On cardiovascular examination , pan-systolic murmur was heard , loudest at the left sternal border. 3 sets of blood cultures were taken consecutively . Transthoracic echocardiography TTE was done , which revealed vegetation on the tricuspid valve with TR.From the given history , which organism is most likely to be positive in blood cultures?Streptococcus sanguisEnterococcus faeciumCoxiella burnetiiStaphylococcusaureus  <response>: From the given history - Probable diagnosis is Infective endocarditis Ho IV drug abuse - most common organism- Staphylococcus aureus- Culture positive endocarditis. Most common organism in IV drug abusers causing Infective Endocarditis Overall Staphylococcus aureus Right side of Hea Staphylococcus aureus Left side of Hea Enterococcus faecium Single ve blood culture for Coxiella Burnetii is considered a major criteria for diagnosis of IE. Culture negative endocarditis- HACEK group. 