Interspinous Bursitis due to Staphylococcus aureus in an Adolescent.

BACKGROUND

Interspinous bursitis is exceptionally rare in children, contrasting with degenerative forms in adults.

CASE PRESENTATION: A 16-year-old male presented with acute severe low back pain, fever (39°C), and focal L3-L5 tenderness. CRP was 233 mg/L; blood cultures grew methicillin-susceptible Staphylococcus aureus. Imaging progression (US, CT-scan, MRI, PET-CT) confirmed L3-L4 interspinous bursitis without bone/disc involvement, distinguishing it from spondylodiscitis.

MANAGEMENT: Cefazolin IV (10 days) followed by oral ciprofloxacin (4 weeks), a lumbar brace, and rehabilitation yielded complete recovery.

CONCLUSIONS

Pediatric interspinous bursitis presents as febrile back pain via hematogenous dissemination. MRI is diagnostic, excluding spondylodiscitis. Conservative management with early antibiotic switch is effective when imaging excludes bone/disc involvement. This case highlights distinguishing features and optimal management of this rare pediatric entity.