A 77-year-old man presented to the emergency room with a 1-month history of persistent low back pain with the absence of vital sign abnormalities. On several previous orthopedic surgery clinic visits, pathological back pain had not been considered and pain killers had been prescribed because he had low back pain due to lumbar spinal canal stenosis. He was admitted to the intensive care unit for infectious spondylodiscitis and infective endocarditis with disseminated abscess caused by methicillin-resistant Staphylococcus aureus. Shock refractory tachyarrhythmia could not be managed with antiarrhythmic agent in the intensive care unit. Intractable low back pain and persistent tachyarrhythmia were adequately managed by pain control with fentanyl in the intensive care unit. Infectious spondylodiscitis and infective endocarditis were effectively managed with anti-methicillin-resistant Staphylococcus aureus drugs, initially in rotational usage, but the patient died of extended-spectrum beta-lactamase-producing Escherichia coli pneumonia on day 50 of hospitalization. Infectious spondylodiscitis should have been considered for persistent low back pain with hemodialysis, fever, and a history of device implantation. Pain management may be necessary for persistent tachycardia that proves unresponsive to usual antiarrhythmic medications.