A case of congenital midline fistula of the upper lip.

Congenital fistulas of the lip are commonly found in the lower lip and accompany cleft lip. They are seen as a symptom of Van der Woude syndrome, which is predominantly hereditary. In contrast, congenital fistulas of the upper lip are rare. A number of hypotheses have been proposed to explain the pathogenesis of fistulas of the upper lip, including fusion failure of facial prominences and absence of mesoblasts, suggesting a relationship between this condition and the development of cleft lip. The pathogenesis of this disorder has been attracting attention. We report the case of a 5-year-old girl with congenital fistula of the upper lip.