summary Disc space infections in the pediatric population are a common source of fever and low back pain and are caused by systemic infections Diagnosis is made with blood cultures and MRI Treatment includes bed rest, immobilization, and antibiotics for 4-6 weeks for early infection without abscess. Surgical debridement followed by antibiotic treatment is indicated in the presence of an abscess and/or lack of improvement with nonoperative treatment Epidemiology Demographics more common in pediatric patients compared with adults more common in males usually affects patients <5 y/o Anatomic location most commonly occurs in the lumbar spine (50-60%) Etiology Pathophysiology pathoanatomy in children, blood vessels extend from the cartilaginous endplate into the nucleus pulposus this allows direct inoculation of the disc space infection may spread from the endplate to the disc space and vertebral body in adults, blood vessels extend only to the annulus fibrosus this limits the incidence of isolated disc space infections in adults microbiology Staphylococcus aureus most common causative organism (>80%) tuberculosis always consider, especially if the patient is not improving with first-line antibiotics Salmonella consider in patients with sickle cell anemia Anatomy Disc anatomy in children, blood vessels extend from the cartilaginous endplate into the nucleus pulposus in adults, blood vessels extend only to the annulus fibrosus Presentation Symptoms depend on the age of the child toddlers painful limping or refusal to sit or walk loss of appetite fever (present in only 25%) abdominal pain older children back pain with point tenderness Physical exam tender to palpation over the involved level limited range of motion Imaging Radiographs radiographic findings are unreliable earliest radiographic manifestation occurs at 1 week findings usually normal radiographs early in the process loss of lumbar lordosis may be the earliest radiographic sign disc space narrowing (10-21 days after infection onset) endplate erosion (10-21 days after infection onset) MRI diagnostic test of choice Studies Serum labs ESR high-normal or mildly elevated C-reactive protein high-normal or mildly elevated WBC high-normal or mildly elevated Blood cultures to identify the organism Treatment Nonoperative bed rest, immobilization, and antibiotics for 4-6 weeks indications early infection with no abscess or displacement of the thecal sac modalities initial treatment consists of parenteral antibiotics directed against Staphylococcus aureus for 7-10 days follow-up monitor serial labs to assess the efficacy of antibiotic treatment CRP is the most sensitive marker for monitoring the patient's response to antibiotic therapy obtain a CT-guided biopsy if there is no response rule out tuberculosis Operative surgical debridement followed by antibiotic therapy indications late infection paraspinal abscess with associated neurologic deficits limited response to nonoperative treatment technique obtain cultures followed by antibiotic therapy and bracing Complications Long-term narrowing of the disc space Fusion between vertebrae Back pain