Infantile lumbosacral spinal subdural abscess with sacral dermal sinus tract

Study Design. Clinical case report of a spinal subdural abscess in an infant presenting with sacral dermal sinus tract (DST). Objectives. To suggest that sacral DST with caudal direction may require surgical resection as early as possible. Summary of Background Data. DST may induce the formation of a spinal abscess. However, it is sometimes difficult to decide on early surgical resection for DST, especially in cases that are located at a lower level than the lumbar spine and directed caudally that is not accompanied by cerebrospinal fluid leakage. Methods. A 9-month-old girl was transferred due to intermittent fever and vomiting, with the midline sinus of the lower back at the second sacral spinal level. She showed mild tenderness of the lower back and slight weakness of both lower extremities with increased residual urine volume of the bladder. Magnetic resonance imaging (MRI) showed that the low-lying sacral DST traced into the subdural space with caudal orientation, and the presence of extensive subdural spinal abscess from the first lumbar spine to the fourth sacrum. Results. Emergency resection of the sacral DST was performed after laminotomy from the first lumbar spine to the second sacrum, and the subdural spinal abscess was also surgically removed. After 8 weeks of intravenous antibiotic treatment, she showed no neurologic deficit and no evidence of residual abscess on MRI. Conclusion. We suggest that even low-lying sacral DST may require surgical resection as early as possible because it may result in indolent and extensive spinal abscesses.