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Bacterial endocarditis with AACEK (HACEK) organisms
Lindsey R Kuohn1, Richard Ro1, Daniel Bamira1
1Leon H Charney Division of Cardiology, New York University Langone Health, New York, New York, USA.
Insights
The AACEK group (Aggregatibacter, Cardiobacterium, Eikenella, Kingella) rarely causes endocarditis. This case series details three instances of AACEK-related endocarditis, emphasizing diagnostic imaging roles.
Area of Science:
- Infectious Diseases
- Cardiology
- Microbiology
Background:
- The AACEK group (Aggregatibacter, Cardiobacterium, Eikenella, and Kingella) are known, but infrequent, causes of infective endocarditis.
- These Gram-negative organisms were formerly known as the HACEK group.
Observation:
- This case series presents three patients with infective endocarditis caused by AACEK organisms, affecting both native and prosthetic valves.
- Cardiobacterium hominis was identified in two patients, while Aggregatibacter aphrophilus was implicated in the third.
- A dental source of infection was noted in two patients, and all cases presented with subacute endocarditis.
Findings:
- AACEK organisms typically cause an indolent infection.
- Multimodality imaging, particularly transesophageal echocardiography, is critical for diagnosing AACEK endocarditis.
- Imaging aids in assessing native and prosthetic valve involvement and delineating abscess extent in prosthetic valve infections.
Implications:
- This study underscores the importance of considering AACEK organisms in the differential diagnosis of subacute endocarditis.
- Transesophageal echocardiography is vital for accurate diagnosis and management of AACEK endocarditis.
- Early recognition and appropriate imaging can improve outcomes for patients with rare causes of endocarditis.
Introduction:
Gram-negative organisms of the AACEK group, formerly known as HACEK, rarely cause endocarditis.
Case Series:
We present three cases of bacterial endocarditis, involving native and prosthetic valves, caused by AACEK organisms. In two patients, Cardiobacterium hominis was the responsible organism, and in a third, Aggregatibacter aphrophilus was implicated. A dental source of infection was identified in two patients, and in all three patients, the presentation of endocarditis was subacute.
Discussion:
This case series highlights the indolent nature of infection with the AACEK organisms. It also demonstrates the crucial role of multimodality imaging, especially transesophageal echocardiography, in the diagnosis of AACEk endocarditis of both native and prosthetic valves, and in delineating the extent of abscess in those with prosthetic valve infection.
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