Congenital dermal sinus with extensive intramedullary expansion and an infected spinal epidermoid cyst in an infant.

An 11-month-old female child presented with progressive weakness involving both lower limbs and left upper limb. There was hypertonia and hyperreflexia in the affected limbs. This was associated with multiple episodes of urinary tract infection and overflow incontinence of the urinary bladder. Magnetic resonance imaging of the spine revealed extensive intramedullary expansion of a congenital dermal sinus. There was a cystic lesion along the lower end of the sinus tract. Surgical exploration had confirmed the presence of an infected epidermoid cyst along with the dermal sinus tract. The entire tract as well as the abscessed epidermoid cyst was removed. Following this, the child showed gradual improvement of neurological function and bladder dysfunction. This is perhaps the first report in current literature of a congenital dermal sinus tract with such an extensive intramedullary extension (almost the entire spine) and an infected epidermoid tumor in an infant.