Antimicrobial Treatment The principles of treatment of pediatric endocarditis are simi- lar to those for treatment of adult endocarditis.2 In patients who are not severely ill and whose blood cultures are still negative, or whose cultures may be positive for organisms that are frequently contaminants, it is reasonable to withhold antibiotic drugs for 48 hours while additional blood cultures are obtained. A prolonged course of therapy (at least 2 weeks and often 4 8 weeks; Table 6) has been the recommended practice for several reasons. Organisms are embedded within the fibrin-platelet matrix and exist in very high concentrations with relatively low rates of bacterial metabolism and cell divi- sion, which results in decreased susceptibility to -lactam and other cell wall active antibiotic drugs.105,106 Bactericidal rather than bacteriostatic antibiotic drugs should be chosen whenever possible. This recommendation is based on past reports of treatment failures and relapses when only bacteriostatic antibiotic drugs were given. In infants and children, one should use intravenous antibiotic drugs rather than intramuscular agents because of the patients small muscle mass. Outpatient (home) intravenous treatment of endocarditis may be considered in selected patients after initial treatment in the hospital and confirmation that these patients are hemodynamically stable and afebrile, have nega- tive blood cultures, and are not at high risk for complications. Additionally, patient and parent adherence to the medical plan is important. Frequent home monitoring by a home health nurse who assesses wellness, adherence to drug therapy, absence of complications (see Recommendations 4 and 5 for this section), and absence of drug toxicity are parts of the plan. Such a standard would reasonably include prompt (minutes to hours) access to medical and surgical care and cardiac follow- up should complications develop. 