Streptomyces morookaense spinal suppurative infection: a case report

PURPOSE: Streptomyces species are ubiquitous soil actinomycetes and a major source of antibiotics, but invasive human infection with spinal involvement is exceedingly rare and may mimic tuberculous or fungal spondylodiscitis. We report a thoracic suppurative vertebral infection caused by Streptomyces morookaense and highlight an integrated diagnostic approach. METHODS: A 66-year-old woman with no known immunodeficiency developed progressive thoracic back pain one month after severe trauma with open wounds. CT/MRI showed osteolytic endplate destruction at T3-T4 with paravertebral abscess formation. Fluoroscopy-guided percutaneous biopsy of the T4 vertebral body was performed for histopathology, culture, and metagenomic next-generation sequencing (mNGS). RESULTS: Histopathology demonstrated fibrinous exudate, necrosis, and inflammatory granulation tissue with fragmented trabeculae, without granuloma or caseous necrosis; acid-fast staining was negative. Vertebral tissue culture grew Streptomyces spp, and mNGS identified high-abundance sequences matching S. morookaense. Intravenous piperacillin/tazobactam led to rapid pain relief and normalization of inflammatory markers within one week, and no recurrence was observed during follow-up. CONCLUSION: This case suggests that Streptomyces morookaense has the potential to involve the thoracic spine in immunocompetent individuals. For unexplained spinal infections with negative routine tests, percutaneous vertebral sampling with integrated interpretation of pathology, culture, and mNGS can improve detection of rare pathogens and help avoid inappropriate empirical therapy.