A 42-year-old woman from rural Rajasthan presents with a 6-week history of mid-thoracic back pain and constitutional symptoms. MRI shows destruction of T7–T8 vertebral bodies with a small epidural abscess but no cord compression. Neurological examination is normal. ESR is 82 mm/hr. She is HIV-negative and has no comorbidities. What is the most appropriate next step in management?