Familial caudal regression syndrome with complex spinal dysraphism presenting as recurrent cutaneous infection.

Background: Caudal regression syndrome (CRS) is a rare congenital disorder characterized by varying degrees of sacral agenesis and spinal dysraphism. Although most cases are sporadic and associated with maternal diabetes, familial occurrence with variable phenotypic expressivity across generations has rarely been described. Case Description: We report a 12-year-old boy with CRS presenting with recurrent midline pustular lesions since birth, intermittent urinary incontinence, and lower-limb pain. Magnetic resonance imaging revealed sacral agenesis with preservation of S1, a low-lying conus medullaris consistent with tethered cord, and features of lipomyelocele. He underwent L4-S1 laminectomy and detethering under intraoperative neuromonitoring. Intraoperatively, a cystic lesion adherent to the cauda equina nerve roots was identified and excised. Histopathology confirmed an epidermoid cyst. Postoperatively, the patient remained neurologically stable. Evaluation of his mother revealed partial sacral agenesis on imaging despite minimal neurological symptoms, suggesting familial CRS with variable expressivity. Conclusion: This case highlights the importance of considering underlying spinal dysraphism in children with recurrent midline cutaneous infections and supports targeted imaging of first-degree relatives in suspected familial CRS. Careful surgical technique with intraoperative neuromonitoring is valuable in managing complex dysraphic anatomy.