First Korean Case of Helcococcus kunzii Bacteremia in a Patient with Diabetes

Identification and Clinical Significance of Helcococcus kunzii in Human Samples

“…MALDI-TOF mass spectrometry accurately identified all 40 isolates to the species level (score of Ͼ2.0), while both rrs and sodA sequencing also unambiguously provided species-level identification. Only two recent papers reported the use of MALDI-TOF mass spectrometry for H. kunzii identification (23,24), and we confirmed here using a large panel of strains that this new method is reliable for species-level identification of H. kunzii. This is the largest case series of infections caused by H. kunzii, which can now be easily identified with modern methods (particularly MALDI-TOF mass spectrometry).…”

“…However, it has sometimes been isolated in pure cultures, underlining that H. kunzii is able to act as a sole pathogen (18-24). In our study, H. kunzii was detected as the unique pathogen in two cases of osteomyelitis, confirming its opportunistic role, as previously reported in different types of infections such as bacteremia, pleural empyema, implantable cardiac device infection, prosthetic joint infection, and brain abscess (18)(19)(20)(21)(22)(23)(24). As opposed to bloodstream infections reported in the literature, the unique blood isolate in our study was recovered from a polymicrobial specimen (with H. kunzii, S. aureus, Proteus sp.…”

“…Most isolates included in this study (31/39, 79%) were recovered from lower extremity wounds as reported in the literature (20/31, 65%) (13,14,16,23,24). Interestingly, a study on the incidence of skin colonization demonstrated that 10% (12/120) of the foot specimens collected from podiatry patients were positive for H. kunzii (including two-thirds of specimens from diabetic patients), whereas only one specimen (2%) from a healthy volunteer was positive (14).…”

“…This predominance of H. kunzii was also demonstrated in venous leg ulcers where it was the fourth most frequently seen bacterial species (22%) in patient wounds, after Staphylococcus aureus (64%), Corynebacterium striatum (61%), and Pseudomonas aeruginosa (33%) (27). As reported here, patients are usually older than 57 years of age (5,13,16,17,19,21,23,24). H. kunzii was mostly isolated with concomitant bacteria (95% of cases), particularly staphylococci, Enterobacteriaceae, and anaerobes, as previously described (5,13,(15)(16)(17).…”

“…It has also been found in cultures of skin/soft tissue abscesses (1,6,16,18,19). A few observations of invasive H. kunzii infections (bacteremia, pleural empyema, implantable cardiac device infection, prosthetic joint infection, and brain abscess) have also been reported (20)(21)(22)(23)(24). Of note, H. kunzii was isolated once from a sow with purulent urocystitis, suggesting its possible pathogenic role in pigs (25).…”