Happle-Tinschert Syndrome: A Case Report of Unilateral Segmentally Arranged Basaloid Follicular Hamartoma with Scoliosis and Review of Literature

Happle-Tinschert syndrome is a rare disease characterized by unilateral, segmentally arranged basaloid follicular hamartoma (BFH) with osseous, dental, and cerebral anomalies. Although BFH has been demonstrated to be associated with mutations in the patched gene, the genetic basis for Happle-Tinschert syndrome is still unknown. We describe a case of Happle-Tinschert syndrome in a 26-year-old female. The patient presented with unilateral skin color change to brownish papules and atrophoderma following the development of Blaschko's lines, plantar pitting, and nail dystrophy on the right side of the body. She also had scoliosis, hemihypotrophy, and dental anomalies. The skin lesions were histologically confirmed as BFHs. Next-generation sequencing of the patient's genomic DNA obtained from a peripheral blood sample identified no pathogenic mutation. This case illustrates the characteristic clinical features of Happle-Tinschert syndrome. Thus far, 14 cases of Happle-Tinschert syndrome have been reported, and we report another case of this syndrome.