# Kingella kingae Endocarditis and Septic Pulmonary Emboli in a 12‐Year‐Old Male With Repaired Tetralogy of Fallot and a Bioprosthetic Pulmonary Valve

## TL;DR

A 12-year-old with a repaired heart condition developed a rare infection caused by Kingella kingae, requiring advanced testing and surgery.

## Contribution

Demonstrates the use of molecular diagnostics in identifying culture-negative endocarditis caused by K. kingae in a pediatric patient.

## Key findings

- Kingella kingae was identified as the cause of infective endocarditis using cell-free DNA and PCR.
- The patient developed septic pulmonary emboli, necessitating valve replacement.
- Molecular diagnostics proved critical in managing culture-negative endocarditis in this case.

## Abstract

Kingella kingae, typically known for causing osteoarticular infections in young children, is an emerging cause of infective endocarditis (IE) in older children with congenital heart disease. This report describes a 12‐year‐old with repaired tetralogy of Fallot and a bioprosthetic pulmonary valve who developed culture‐negative IE due to K. kingae, confirmed by microbial cell‐free DNA testing and valve tissue PCR. His course was complicated by septic pulmonary emboli, requiring valve replacement. The case highlights the role of molecular diagnostics in managing culture‐negative IE and the need for timely surgical intervention in the presence of embolic complications.