Focal Dermal Hypoplasia

Clinical Characteristics
Ocular Features: 

Features have considerable heterogeneity and few patients have all of them.  Some ocular abnormalities are found in 40% of patients.  Microphthalmia is common and many patients (30%) have colobomas of the iris and choroid.  Some patients have dislocated lenses.  Distinctive peripheral corneal lesions consisting of discrete vascularized subepithelial opacities have been described.  Occasional patients have conjunctival or lid margin papillomas.  Strabismus and nystagmus are common.

Systemic Features: 

This disorder has a wide variety of clinical features and many occur in only a few patients.  The skin has focal areas of hypoplasia with hypopigmentation, often appearing in a streak or linear pattern.  These areas may be present at birth and contain bullae or urticarial lesions with signs of inflammation.  Telangiectases and herniated fat may appear in these areas.   Oral, esophageal, and laryngeal fibrovascular papillomas occur but they may also be seen in the perineal, vulvar, and perianal areas.  These may be large, friable, and recurrent.  The teeth erupt late and are usually hypoplastic.  The nails are often dysplastic and the hands and feet may be 'split' with syndactyly of the third and fourth fingers giving a 'lobster claw' appearance.  Polydactyly may be present.  Most have thin 'protruding' ears.  A variety of skeletal anomalies have been reported including absence of metatarsals and metacarpals.  A considerable number of patients have mild to moderate mental deficits.  Severely affected females may die in infancy.

Genetics

This is considered an X-linked dominant disorder with lethality in males.  However, numerous affected males (>30) and rare instances of father-to-daughter transmission have been reported and it has been suggested that half-chromatid mutations or postzygotic somatic mosaicism in these males might be responsible.  Mutations in the PORCN gene (Xp11.23) have been associated with FDH.

Treatment
Treatment Options: 

Surgery may be required for the papillomas if they are obstructive.

References
Article Title: 

References

Lueder GT, Steiner RD. Corneal abnormalities in a mother and daughter with focal dermal hypoplasia (Goltz-Gorlin syndrome). Am J Ophthalmol. 1995 Aug;120(2):256-8.

PubMedID: 7639315

Brady PD, Van Esch H, Fieremans N, Froyen G, Slavotinek A, Deprest J, Devriendt K, Vermeesch JR. Expanding the phenotypic spectrum of PORCN variants in two males with syndromic microphthalmia. Eur J Hum Genet. 2014 Jul 16.  [Epub ahead of print] PubMed PMID: 25026905.

PubMedID: 25026905

Goltz RW. Focal dermal hypoplasia syndrome. An update. Arch Dermatol. 1992 Aug;128(8):1108-11.

PubMedID: 1497368

Maas SM, Lombardi MP, van Essen AJ, Wakeling EL, Castle B, Temple IK, Kumar VK, Writzl K, Hennekam RC. Phenotype and genotype in 17 patients with Goltz-Gorlin syndrome. J Med Genet. 2009 Oct;46(10):716-20.

PubMedID: 19586929