Superadded Staphylococcus Aureus Spondylodiscitis on Mycobacterium Tuberculosis Spondylodiscitis Post CT Guided Biopsy: An Iatrogenic Complication?

Introduction: Co-existing tuberculous spondylodiscitis and pyogenic spondylodiscitis at the same site have been reported in literature. But a sequential involvement with a possible iatrogenic component has not been described to the best of our knowledge. Here we present a case of Spinal TB diagnosed with CT guided biopsy, one month later presenting as pyogenic discitis and paraparesis, secondary to superadded Staphylococcus aureus. Case Report: A 55 years old female with diabetes mellitus and Hypertension was investigated elsewhere for sudden onset of upper back ache. Her MRI revealed spondylodiscitis of D6- D7. CT guided biopsy was done which showed only Tubercular granuloma and Antitubercular therapy was started elsewhere. One month after the biopsy, she presented with progressive weakness and high-grade fever. Repeat MRI revealed increase in abscess size and cord compression. An epidural abscess drainage and posterior stabilization was done. Culture revealed Staphylococcus aureus. Appropriate culture sensitive antibiotics were started along with antitubercular medications. Patient gradually recovered neurologically. She is able to walk independently at one and six months postsurgery. Discussion: Spondylodiscitis could be bacterial, granulomatous or parasitic. Each has distinctive features and patterns which will lead us to a provisional diagnosis even without tissue confirmation. MRI is the investigation of choice. A definite tissue diagnosis is needed before starting patient on medical treatment. CT guided biopsy could give the necessary tissue diagnosis in the absence of neurological involvement. But can it become a source for another infection? With no other focus of infection found, we have to speculate that the invasive procedure was the source by local inoculation. Conclusion: Even after diagnosis of TB or pyogenic infection is made, the possibility of a second co-existing infection should always be entertained. Complete investigations - bacterial, fungal and tubercular cultures, MTB PCR test and biopsy - should be done in all cases of suspected infection. All invasive procedures like CT guided biopsy, should be done under strict aseptic precautions.