Infective Endocarditis in Individuals with Unrepaired or Incompletely Repaired Congenital Heart Disease in Low- and Middle-income Countries: A Scoping Review of Case Reports and Case Series

Individuals with unrepaired or incompletely repaired congenital heart disease (CHD) are at risk of infective endocarditis (IE). In low- and middle-income countries (LMICs), this burden is compounded by diagnostic delays, persistent defects, and poor infrastructure. This scoping review aimed to map the reported clinical presentation, microbiological profile, and outcomes, including in-hospital mortality where documented, of IE in this population. We searched PubMed, Embase, Google Scholar, Cochrane Central, African Journal Online, and Directory of Open Access Journals Online for English and French records from January 2007 to June 2026, focusing on individuals with unrepaired or incompletely repaired CHD and IE in LMICs. Eleven studies, comprising 58 patients across three LMIC regions, including ten case reports and one retrospective case series, were included in the review. Patient ages ranged from 0 to 45 years. Tetralogy of Fallot and ventricular septal defect (31.3% in the retrospective case series) were the most frequently reported uncorrected lesions. Clinically, presentation was predominantly subacute, with fever and a new or changed cardiac murmur reported in nearly all cases (89.6% and 85.4%, respectively, in the case series); acute presentations (symptom duration < 10 days) were uncommon (14.6% in the case series). Right-sided involvement predominated among reported cases, and vegetations were identified on echocardiography in the majority of episodes where imaging was performed. In several patients, CHD was identified for the first time only at the point of IE presentation. Diagnostically, 43.9% of episodes with antemortem blood culture data were culture-negative. In the case series, 47.9% of pre-hospital empirical antibiotic use was documented. Among culture-positive episodes (56.1%), Streptococcal species predominated, led by Viridans group Streptococci (18.8% in the retrospective case series), followed by Staphylococcal (n = 6), Enterococcal (n = 3), and Gram-negative organisms (8.3% in the retrospective case series). One patient was diagnosed with IE only post-mortem, with Enterococcus faecalis recovered from valve culture. In-hospital mortality in the case series was 27.1%. Based on the evidence identified, IE in individuals with unrepaired or incompletely repaired CHD is associated with substantial morbidity in resource-limited settings, compounded by a subacute, often non-specific clinical presentation that delays recognition, particularly where CHD itself may remain undiagnosed until IE develops. This diagnostic delay, together with microbiological deficits and restricted surgical access, underscores the need to strengthen blood culture practices before antibiotic administration, expand echocardiographic access for earlier CHD detection, and invest in CHD surgical capacity across LMICs, particularly in sub-Saharan Africa, where no eligible studies were identified. These are priority areas for clinical practice and future research.