A 38-year-old man from rural Maharashtra presents with a 4-month history of progressive back pain, low-grade fever, and weight loss. Examination reveals kyphosis and tenderness over the mid-thoracic spine. MRI shows T2 hyperintense signal in the T5–T6 vertebral bodies with anterior vertebral collapse and a thin epidural collection. ESR is 68 mm/h and CRP is elevated. Sputum smear microscopy is negative. What is the most appropriate next step in management?