summary Disk Space Infections in the pediatric population are a common source of fever and low back pain caused by systemic infections in young children. Diagnosis is made with blood cultures and MRI studies. Treatment is bed rest, immobilization, and antibiotics for 4-6 weeks for early infection with no abscess. Surgical debridement followed by antibiotic treatment is indicated in the presence of an abscess and/or lack of improvement with nonoperative therapy. Epidemiology Demographics more common in pediatric patients relative to adults more common in males usually affects patients less than 5 years old Anatomic location most common in lumbar spine (50-60%) Etiology Pathophysiology pathoanatomy in children blood vessels extend from the cartilaginous end plate into the nucleus pulposus this allows direct inoculation of the disc infection may spread from the end plate to the disc space and vertebral body in adult patients, blood vessels extend only to the annulus fibrosis this limits the incidence of isolated disc space infections in adults microbiology staphylococcus aureus is most common causative organism (>80%) tuberculosis always consider as organism, especially if patient is not improving with first line antibiotics salmonella in sickle cell anemia patients, salmonella may be the causative organism Anatomy Disc anatomy in pediatric patients, blood vessels extend from the cartilaginous end plate into the nucleus pulposus in adult patients, blood vessels extend only to the annulus fibrosis Presentation Symptoms depend on age of child toddler refusal to sit or walk, or painful limping loss of appetite fever (only 25% of patients will be febrile) abdominal pain older children back pain with point tenderness Physical exam tender to palpation over involved level limited range of motion Imaging Radiographs radiographic findings are unreliable earliest manifestation is at 1 week findings usually normal radiographs early in process loss of lumbar lordosis may be earliest radiographic sign disc space narrowing (10-21 days after infection begins) endplate erosion (10-21 days after infection begins) 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 blood cultures should be obtained to identify organism Treatment Nonoperative bedrest, immobilization, and antibiotics for 4-6 weeks indications early infection with no abscess or displacement of thecal sac modalities initial treatment is with parenteral antibiotics directed at Staph aureus for 7-10 days followup watch serial labs to monitor efficacy of antibiotic treatment CRP is the most sensitive in monitoring this patient's response to antibiotic therapy obtain CT-guided biopsy if no response (rule out TB) Operative surgical debridement followed by antibiotic treatment indications late infection paraspinal abscess in the presence of neurologic deficits limited responsiveness to nonoperative measures technique important to obtain cultures followed with antibiotics and bracing Complications Long term narrowing of disk space Fusion between vertebra Back pain