Bacterial endocarditis with AACEK (HACEK) organisms

Abstract

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.

Keywords: AACEK; HACEK; TEE; bioprosthesis; endocarditis; valve replacement.