New valvular regurgitation (worsening or changing of preexisting murmur not sufficient) Minor criteria 1. Predisposition: predisposing heart condition or IV drug use Vascular phenomena: major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, and Janeway lesions Immunologic phenomena: glomerulonephritis, Osler nodes, Roth s spots, and rheumatoid factor Microbiological evidence: positive blood culture but does not meet a major criterion as noted above or serological evidence of active infection with organism consistent with IE HACEK indicates Haemophilus species, Aggregatibacter species, Cardiobacterium hominis, Eikenella corrodens, and Kingella species; IE, infective endocarditis; IV, intravenous; TEE, transesophageal echocardiography; and TTE, transthoracic echocardiography. *Includes nutritionally variant strains (Abiotrophia species). Excludes single positive cultures for coagulase-negative staphylococci and organisms that do not cause endocarditis. Modified from Durack et al74 (copyright 1994, Elsevier) and Li et al75 (copyright 2000, Oxford University Press) with permission from the publishers. Baltimore et al Infective Endocarditis in Childhood: 2015 Update 1495 and Granulicatella species). The laboratory must subculture positive blood culture bottles on special media supplemented with l-cysteine or pyridoxal phosphate to isolate these organisms. VGS, Abiotrophia or Granulicatella species, or enterococci are most associated with native valve endocar- ditis and endocarditis occurring >60 days after cardiac sur- gery. IE produced by these organisms usually is subacute in presentation. IE associated with indwelling vascular catheters, prosthetic material, and prosthetic valves frequently is caused by S aureus or coagulase-negative staphylococci. These organisms often are implanted at the time of surgery, and infection manifests within 60 days after cardiac surgery, but coagulase-negative staphylococci infection may present as late as 1 years after surgery. Among newborn infants, S aureus, coagulase-negative staphylococci, and Candida species are the most common causes of IE.9,13 Less frequently, group B Streptococcus, enteric Gram-negative rod species, and S pneumoniae cause IE in this population. 