Spinal dermal sinuses and dermal sinus-like stalks analysis of 14 cases with suggestions for embryologic mechanisms resulting in dermal sinus-like stalks.

BACKGROUND: Spinal dermal sinuses consist of an epithelium-lined tract extending from the skin towards the spinal cord, often resulting in infections or tethered cord syndrome. Recently, a variant called dermal sinus-like stalk was described as an analogous tract but not containing an epithelium-lined lumen. AIMS: We aimed to describe the findings in our patients, subdivide our specimens into both conditions, compare the characteristics of both groups and search for possible embryologic mechanisms of dermal sinus-like stalks.
METHODS: We performed a retrospective analysis of all patients operated in our hospital for both conditions between 1996 and 2012.
RESULTS: 14 patients were operated upon for spinal dermal sinuses (n = 5) and spinal dermal sinus like-stalks (n = 9). Patients were mainly referred from other hospitals due to skin abnormalities and were evaluated at mean age of 7 weeks and operated upon at mean age of 1 year and 2 months. Primary reason for referral was skin abnormalities in both groups, though there were two cases of meningitis in dermal sinus patients and 2 of recurrent urinary tract infections in dermal sinus-like stalk patients. Consistent with previous findings, dermal sinus-like stalk patients do not have a history of meningitis, lack dermoid or epidermoid tumours along their tract, and are histologically of pure mesodermal origin. Dermal sinus-like stalks might result from interposition of mesenchyme during primary or secondary neurulation.
CONCLUSIONS: We consider dermal sinus-like stalks as a rare but currently under diagnosed condition with different clinical, pathological and probably also embryologic characteristics compared to spinal dermal sinuses.