Infected congenital lumbosacral dermal sinus tract with conus epidermoid abscess: a rare entity

Dermal sinus is more commonly associated with intradural dermoid than an epidermoid cyst. Conus epidermoid cyst with dermal sinus is a rare entity. We are presenting a rare case of infected conus epidermoid cyst along with the dermal sinus in an 18-month-old girl presented with flaccid paraparesis with sphincter dysfunction and timely intervention leads to complete recovery. We had searched PubMed for previously reported similar cases and did a case-based review of the literature.

This 18-month-old girl with discharging lumbosacral sinus with fever since 3 days presented with flaccid paraparesis with sphincter dysfunction. Preoperative magnetic resonance imaging (MRI) showed a large enhancing lesion from L1-S1 along with the dermal sinus tract. Complete excision of the cyst along with the sinus tract, followed by long-term antibiotic therapy. The excision of the infected cyst was done through myelotomy under neuromonitoring, while some part of the capsule densely adherent to the neural tissue was left behind. The patient gradually improved following surgery and motor power of the lower limbs were [Formula: see text] while going home. Histopathology revealed epidermoid cyst with secondary inflammatory tissue. Follow-up MRI of the spine showed excision of the dermal sinus tract and cyst with postoperative changes. At 1-year follow-up, the patient was asymptomatic without any focal deficits.

Early surgical intervention followed by long-term antibiotic therapy is a must for good functional recovery in patients of an infected dermal sinus tract with associated cyst. While excising cyst through myelotomy, some part of the capsule densely adherent to neural tissue may be left behind. Regular follow-up in the first year of surgery is essential to look for the recurrence of the lesion.