Focal dermal hypoplasia is a multisystem disorder characterized primarily by involvement of the skin, skeletal system, eyes, and face. Skin manifestations present at birth include atrophic and hypoplastic areas of skin; cutis aplasia; fat nodules in the dermis manifesting as soft, yellow-pink cutaneous nodules; and pigmentary changes. Verrucoid papillomas of the skin and mucous membranes may appear later. The nails can be ridged, dysplastic, or hypoplastic; hair can be sparse or absent. Limb malformations include oligo-/syndactyly and split hand/foot. Developmental abnormalities of the eye can include anophthalmia/microphthalmia, iris and chorioretinal coloboma, and lacrimal duct abnormalities. Craniofacial findings can include facial asymmetry, notched alae nasi, cleft lip and palate, and pointed chin. Occasional findings include dental anomalies, abdominal wall defects, diaphragmatic hernia, and renal anomalies. Psychomotor development is usually normal; some individuals have cognitive impairment.

Autoinflammation with arthritis and dyskeratosis (AIADK) is characterized by recurrent fever, widespread skin dyskeratosis, arthritis, elevated biologic markers of inflammation, and mild autoimmunity with a high transitional B-cell level (summary by Grandemange et al., 2016).

Congenital juvenile respiratory papillomatosis (JRRP) is an autosomal recessive disorder characterized by the development of recurrent growth of papillomas (warts) on respiratory epithelial cells in the upper airway, particularly the larynx. Patients present in early childhood with hoarse voice and, in severe cases, respiratory stridor due to airway obstruction. Affected individuals may also have mild dermatologic abnormalities similar to those observed in AIADK. While JRRP is a genetic disorder resulting from abnormal activation of the immune system, RRP in general is usually associated with acquired HPV infection, commonly with HPV types 6 and 11 (summary by Drutman et al., 2019).