Helcococcus kunzii as a rare etiological agent of spondylodiscitis partially managed with oral antibiotic therapy in a patient with diabetes mellitus: a case report

BACKGROUND: Previous studies have reported Helcococcus kunzii infection in a range of clinical conditions, including infective endocarditis, umbilical abscesses, bacteremia, diabetic foot infections, and prosthetic joint infections. Diabetes mellitus has been identified as a predisposing condition for infections caused by this pathogen. We report the first documented case of spondylodiscitis caused by Helcococcus kunzii. CASE PRESENTATION: We describe a case of spondylodiscitis caused by Helcococcus kunzii in a 62-year-old man with long-standing type 1 diabetes mellitus who presented to the emergency department with severe, immobilizing lumbar pain. Clinical diagnosis of spondylodiscitis was established by magnetic resonance imaging (MRI). Helcococcus kunzii was isolated from four separate blood culture sets. During surgical intervention, two swabs and two tissue samples were collected. H. kunzii was identified in all specimens using MALDI-TOF mass spectrometry (MALDI-TOF MS) with log scores ranging from 2.30 to 2.52. The patient received intravenous β-lactam antibiotics for ten days, followed by 13 weeks of oral β-lactam antibiotics. Follow-up MRI performed before discharge showed no further evidence of spondylodiscitis. At the 3-month follow-up visit, the patient demonstrated clinical improvement. CONCLUSIONS: This case demonstrates that H. kunzii should be considered a potential etiological agent of pyogenic spondylodiscitis, particularly in patients with diabetes mellitus and associated comorbidities that may compromise skin barrier integrity. MALDI-TOF MS is essential for accurate identification of this organism and should be considered in cases of atypical spondylodiscitis.