Identification of Peptoniphilus harei From Blood Cultures in an Infected Aortic Aneurysm Patient: Case Report and Review Published Literature

Abstract

Gram-positive anaerobic cocci (GPAC) are a commensal part of human flora but are also opportunistic pathogens. This is possibly the first study to report a case of Peptoniphilus harei bacteremia in an abdominal aortic aneurysm (AAA) patient. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) failed to identify the isolate and molecular analysis confirmed it as P. harei. A comprehensive literature review revealed that P. harei is an emergent pathogen. This study serves as a reminder for practicing clinicians to include anaerobic blood cultures as part of their blood culture procedures; this is particularly important situations with a high level of suspicion of infection factors in some noninfectious diseases, as mentioned in this publication. Clinical microbiologists should be aware that the pathogenic potential of GPAC can be greatly underestimated leading to incorrect diagnosis on using only one method for pathogen identification. Upgradation and correction of the MALDI-TOF MS databases is recommended to provide reliable and rapid identification of GPAC at species level in medical diagnostic microbiology laboratories.

Keywords: 16s rDNA sequencing; MALDI–TOF; Peptoniphilus harei; bacteremia; gram-positive anaerobic cocci.