Q. A 27-year-old man has come to your clinic with progressive low back pain for the past two months. He complains of frequent intermittent fever. The pain does not radiate to lower limbs and exacerbates with activity; however, the pain wakes him up during the night. He has no numbness in his lower limbs. He is a marine who served in Afghanistan for six months in 2020. He is under treatment for anxiety but has no other medical condition. He does not smoke and takes no alcohol or illicit drugs. On physical examination, his temperature is 38.1 degrees Celsius (100.58 degrees Fahrenheit), blood pressure is 128/72 mmHg, pulse rate is 86/min, and respiratory rate is 14/min. Body mass index is 19.7 kg/m2. The lumbar spine is tender to percussion. Motions of the spine are painful and limited. The lumbar x-ray only shows a loss of vertebral bony margins and mild osteoporosis in the upper lumbar vertebrae. There are signal changes in the anterior part of the L1 and L2 bodies and the L1-L2 intervertebral disc on lumbar MRI. There is also a fluid collection anterior to the vertebral bodies beneath the anterior longitudinal ligament. What is the best plan for him at this stage?