In paediatric patients with Staphylococcus (S) aureus bacteraemia (SAB), 8.8 percent present with S. aureus endocarditis (SAE), a study has shown. Both SAE and SAB are associated with prolonged hospitalization and higher mortality rates.
Key predictors of SAE include congenital heart disease (CHD), protein‒energy malnutrition (PEM), nonimmunocompromised status, and persistent bacteraemia.
“In settings where echocardiography is not immediately accessible, these clinical risk factors can guide the early identification of high-risk patients and support decisions regarding monitoring intensity and timely referral,” the researchers said.
Children diagnosed with SAB at a university hospital in Thailand between 2003 and 2023 were included in this retrospective study. Eligible patients were identified using International Statistical Classification of Diseases and Related Health Problems 10th Revision codes.
The research team defined endocarditis using the modified Duke criteria, in accordance with the 2013 European Society of Cardiology guidelines for the management of endocarditis.
A total of 171 children with SAB were included in the analysis, of whom 15 (8.8 percent) met the criteria for definite infective endocarditis. The most common pathogen in both uncomplicated SAB and SAB complicated by endocarditis was methicillin-sensitive S. aureus. [Pediatr Infec Dis J 2026;45:925-928]
CHD significantly correlated with SAE (p=0.02), as did PEM (p=0.04) and two or more positive blood cultures (p=0.001). On the other hand, an immunocompromised status was associated with a reduced risk (p<0.001). Both SAB and SAE correlated with prolonged hospitalization and increased mortality.
“These findings underscore the importance of early identification and close monitoring of high-risk paediatric patients,” the researchers said. “Larger prospective studies are warranted to validate these risk factors and develop predictive strategies for SAE in children with SAB.”
Diagnostic tool
Endocarditis in suspected patients can be detected using transthoracic echocardiography, but the timing of its use following a positive blood culture relies on clinical judgment, according to the researchers.
“In our cohort, the interval from bacteraemia onset to echocardiography ranged from 0 to 8.5 days, depending on each patient’s clinical presentation,” they said.
Children with CHD tended to undergo echocardiography earlier, and those with persistent bacteraemia needed timely imaging due to their increased SAE risk.
“However, in settings where echocardiography is unavailable or cannot be performed promptly, these clinical risk factors, particularly CHD and persistent bacteremia, become essential indicators for risk stratification,” the researchers said.
“They can help clinicians identify patients who may require closer monitoring, earlier escalation of treatment, or urgent referral to facilities where echocardiography is available,” they added.
Mortality rates
Notably, children have a lower rate of SAE mortality than adults. The mortality rate in the current cohort was consistent with that in previous studies, which ranged from 12.5 percent to 40 percent. [Pediatrics 2005;115:e15-e19; Can J Infect Dis Med Microbiol 2008;19:63-68]
However, no statistically significant difference in mortality was observed between patients with SAE and those with SAB. The 30-day mortality among patients with SAB alone ranged from 2 percent to 5 percent. [Clin Infect Dis 2022;74:604-613; JAMA Pediatr 2016;170:979-986; Paediatr Child Health 2011;16:276-280]
“This was associated with multiorgan dysfunction, osteoarticular focus, multifocal SAB, and necrotizing pneumonia,” the researchers said. “Due to various comorbidities and the highly serious invasive organism, SAE is one of the major causes of mortality.”