Liver and brain abscess caused by Aggregatibacter paraphrophilus in association with a large patent foramen ovale: a case report

Abstract

Introduction: Aggregatibacter paraphrophilus (former name Haemophilus paraphrophilus) is a normal commensal of the oral flora. It is a rare cause of hepatobiliary or intracerebral abscesses.

Case presentation: We report a case of a 53-year-old Caucasian man with a liver abscess and subsequent brain abscesses caused by Aggregatibacter paraphrophilus. The probable source of the infection was the oral flora of our patient following ingestion of a dental filling. The presence of a large patent foramen ovale was a predisposing factor for multifocal abscesses.

Conclusion: In this case report, we describe an unusual case of a patient with both liver and brain abscesses caused by an oral commensal Aggregatibacter paraphrophilus that can occasionally show significant pathogenic potential.

Figure 1

Computed tomography of the abdomen showing a mildly enhancing peripheral hypodense lesion in liver. Scan taken during the initial admission.

Figure 2

Computed tomography of the abdomen showing a metallic artefact (likely dental amalgam) in appendix region. Scan taken during the initial admission.

Figure 3

T1 weighted magnetic resonance imaging of the head showing multiple foci of contrast enhancement (abscesses). Scan taken during the second admission showing lesions suspicious of abscesses near the grey-white junction of both cerebral hemispheres, and a small enhancing lesion in the right cerebellar hemisphere.