A rare case of aggressive pyogenic spondylitis with giant abscesses after vertebral augmentation.

Although Streptococcus constellatus (SC), an opportunistic pathogen, can cause abscesses and empyema. The SC infection after vertebral augmentation (VA) can interfere with patients' daily living activities and can be life-threatening in severe cases. A 67-year-old male complained of lumbar pain for two months. The patient underwent percutaneous vertebroplasty of the second and third lumbar vertebrae two months ago. On admission, laboratory and imaging evidence suggested infection of the second and third lumbar vertebrae with bilateral psoas major and left lumbodorsal abscesses. After three weeks of empirical anti-infective therapy, abscess removal and the second and third lumbar vertebrae fusion with iliac bone graft were performed under general anesthesia. Intraoperative pathology and next-generation sequencing (NGS) examination of the pus suggested SC infection, and oral linezolid was given for 12 weeks after surgery. The infection was eventually cured and the patient achieved satisfactory function. In conclusion, pyogenic spondylitis due to SC infection after VA is a life-threatening complication. In addition to infectious disease consultation and routine etiological screening, NGS is important to identify infection with unknown pathogens. Surgery combined with sensitive antibiotics is appropriate for patients with progressive neurological deficits.