In a patient with back pain and a history of IV drug use, which differential diagnoses should be considered?

• A. Epidural Hematoma
• B. Osteomyelitis, Discitis, Spinal Abscess
• C. Metastatic Cancer
• D. Acute Appendicitis

Answer: (B)

Back pain in someone with a history of IV drug use makes spinal infection the top consideration. IV drug use can introduce bacteria into the bloodstream, and Staphylococcus aureus is a common culprit that can seed the vertebral bodies, spreading to the intervertebral disc (discitis) and even form a spinal abscess. These infections often present with persistent back pain and fever, and exam may reveal focal spinal tenderness. Because the spine is a potential site for serious consequences, prompt imaging with MRI (best with contrast) and blood cultures is essential, followed by appropriate IV antibiotics and, if an abscess or neurologic symptoms are present, surgical consultation for drainage.

Other options are less likely in this context. An epidural hematoma would be more typical with a history of trauma or anticoagulation and may present with acute neurologic changes rather than a subacute infectious process. Metastatic cancer can cause back pain but usually in the setting of a known malignancy or age-related risk factors, and acute appendicitis presents with abdominal, not spinal, symptoms.