Introduction: Spinal dermoid cysts are rare congenital lesions. While MRI can often diagnose dermoid cysts in their typical form, superinfected cysts are challenging to diagnose due to their clinical presentation and nonspecific radiological features.

Case report: Herein, we present the case of a 14-month-old boy with good psychomotor development. Symptoms developed rapidly over a week with torticollis and regression of motor acquisitions. Initially diagnosed with bacterial E. coli meningitis, the onset of paraplegia prompted lumbar MRI, revealing an extensive intracanal collection from L1 to S2. Histology confirmed a suppurative dermoid cyst.

Spinal dermoid cysts are rare and benign pseudotumors resulting from the inclusion of ectodermal elements during the closure of the neural canal between the 3rd and 5th week of embryonic life. Dermoid cysts in the spine are uncommon, accounting for less than 1% of cases. Clinical presentation varies depending on the lesion’s location, often manifesting as cauda equina syndrome. In cases of abscessed forms, the presentation can mimic bacterial meningitis. Surgical excision, though feasible for cyst contents aspiration, may not always achieve complete removal of the capsule.

Conclusion: Dermoid cysts are rare entities, with MRI currently being the preferred imaging modality for their evaluation. Complete surgical excision is seldom achieved. Superinfection significantly worsens the prognosis, affecting both vital and functional outcomes.