Infective Endocarditis in Children

Definition and epidemiology

Infective endocarditis (IE) is microbial infection of the endocardial surface — most often a valve, but also septal defects, mural endocardium, or indwelling cardiac material. In children IE is uncommon but carries substantial morbidity and mortality. The risk substrate has shifted: congenital heart disease (especially with prosthetic material or post-surgical conduits) is now the leading predisposing condition in many settings, alongside indwelling central venous catheters in neonates and immunocompromised children. Rheumatic heart disease remains an important substrate where it is still prevalent, including parts of India. Predominant organisms are viridans group streptococci and Staphylococcus aureus, with coagulase-negative staphylococci important in prosthetic-material and catheter-associated disease.

Clinical features

IE is notoriously protean. Subacute disease presents with prolonged low-grade fever, malaise, weight loss, anorexia and arthralgia; acute S. aureus disease presents with high fever and rapid valvular destruction or embolic events.

• Cardiac: a new or changing regurgitant murmur, heart failure
• Embolic/vascular: splenic or cerebral emboli, septic pulmonary emboli (right-sided/CVC disease), Janeway lesions
• Immunological: Osler nodes, Roth spots, glomerulonephritis, splinter haemorrhages
• Constitutional: persistent fever, splenomegaly, anaemia

Classic peripheral stigmata are less common in children than in adults, so a high index of suspicion in any child with sustained bacteraemia and a cardiac risk factor is essential.

Diagnosis

Diagnosis rests on the 2023 Duke-ISCVID criteria (an update of the modified Duke criteria), integrating microbiology, imaging and predisposing factors into major and minor criteria to classify disease as definite, possible or rejected. The cornerstones are multiple sets of blood cultures drawn before antibiotics and echocardiography (transthoracic first in most children; transoesophageal where windows are poor or prosthetic material is present). The 2023 update broadened major criteria to include newer microbiological methods (PCR, metagenomic sequencing), additional imaging (cardiac CT, [18F]FDG-PET/CT) and intraoperative inspection.

See the full criteria: Infective Endocarditis (2023 Duke-ISCVID)

Red flags

• Persistent bacteraemia/fungaemia with a typical IE organism, especially with prosthetic material or a CVC
• New regurgitant murmur, heart failure, or new conduction abnormality (suggests perivalvular abscess)
• Systemic or pulmonary embolic phenomena, or mycotic aneurysm
• Vegetation on echocardiography, particularly large or mobile
• Fever of unknown origin in a child with congenital or rheumatic heart disease

Management overview

Management combines prolonged targeted antimicrobial therapy with surgical assessment and multidisciplinary care.

1. Cultures first: obtain multiple blood-culture sets before starting antibiotics whenever the patient is stable enough to allow it.
2. Antimicrobial strategy: prolonged bactericidal antibiotic therapy, typically intravenous and several weeks in duration, guided by organism and susceptibilities — empirical regimens cover staphylococci, streptococci and enterococci until cultures direct narrowing; prosthetic-material disease and culture-negative IE warrant specialist microbiology input.
3. Source control: remove or exchange infected catheters/lines and other infected hardware where feasible.
4. Surgery: early cardiac surgical referral for heart failure from valve dysfunction, uncontrolled infection/abscess, large or embolising vegetations, or prosthetic-valve involvement.
5. Multidisciplinary care: an “endocarditis team” (paediatric cardiology, infectious diseases, cardiac surgery, microbiology) and monitoring for complications — embolism, heart failure, conduction disease, renal involvement.
6. Prevention: antibiotic prophylaxis is reserved for the highest-risk cardiac lesions undergoing defined procedures, with emphasis on dental and skin hygiene.

Specific agents, doses and durations depend on organism, susceptibility and the presence of prosthetic material — use a verified antimicrobial reference and infectious-diseases guidance.

References

• Duke-ISCVID 2023 Criteria for Infective Endocarditis
• AHA Scientific Statement on Infective Endocarditis in Childhood
• ESC Guidelines on the management of infective endocarditis

Decision support for qualified clinicians only — verify against current primary guidelines and your clinical judgement.