Schöpf-Schulz-Passarge syndrome: further delineation of the phenotype and genetic considerations.

Schöpf-Schulz-Passarge syndrome is a rare ectodermal dysplasia, characterized chiefly by multiple eyelid apocrine hidrocystomas, palmo-plantar keratoderma, hypodontia, hypotrichosis and nail dystrophy. The clinical spectrum and the most likely inheritance pattern(s) have not yet been completely defined. We report here on two, unrelated patients presenting with additional, previously unreported features, including hypoplastic nipples and optic atrophy. Both individuals were born to consanguineous parents, and one also has affected siblings. A literature review identified 23 additional cases. Multiple eyelid apocrine hidrocystomas, described in all of the cases, are the hallmark of this condition, although they usually appear in adulthood. The concomitant presence of eccrine syringofibroadenoma in most patients and of other adnexal skin tumours in 44% of affected subjects indicates that Schöpf-Schulz-Passarge is a genodermatosis with skin appendage neoplasms. However, the risk of skin and visceral malignancies is not increased. Pedigree study demonstrates that 9 of the 13 published familial cases may be explained by an autosomal recessive mutation, while the remaining pedigrees show apparent vertical transmission compatible with genetic heterogeneity. The benign disease course and advanced age at diagnosis could also suggest locus homogeneity for a recessive mutation with instances of pseudodominant inheritance.