Our patient was a 4-year-old girl with no past medical or family history of interest. She was seen in the dermatology department for evaluation of a lumbosacral patch of hypertrichosis that had been present since birth. Examination revealed a clearly defined triangular area of hypertrichosis situated in the central lumbosacral area (Fig. 1). At the time of consultation there were no signs of spinal cord lesions or alterations of psychomotor development. In view of these findings, lumbosacral magnetic resonance imaging (MRI) was performed to exclude associated spinal dysraphism. This showed an occult meningocele with a defect of closure of the posterior arch, a probable distal dermal sinus tract, and syringomyelic dilatation of the distal vertebral canal (Fig. 2). The patient was diagnosed with occult meningocele with associated lumbosacral hypertrichosis. She remains asymptomatic and is being followed up in neurosurgery.

Figure 1

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Figure 2

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Faun tail is a well-defined area of congenital hypertrichosis, typically of triangular morphology, situated in the central lumbosacral region. It is often associated with defects of closure of the vertebral canal during embryonic development and, even in absence of associated spinal cord symptoms (alterations of sensitivity, strength, or sphincter function), MRI is recommended to rule out or confirm possible associated spinal dysraphism, which will determine the prognosis and management.