Anonychia

For the moth genus, see Anonychia (moth).

Anonychia is the failure to form fingernails or toenails.^[1]

Anonychia
Specialty	Dermatology

It is an anomaly which may be the result of a congenital ectodermal defect, ichthyosis, severe infection, severe allergic contact dermatitis, self-inflicted trauma, Raynaud phenomenon, lichen planus, epidermolysis bullosa, or severe exfoliative diseases.^[2]

Cause

This is rare and is usually due to mutations in the R-spondin 4 (RSPO4) gene which is located on the short arm of chromosome 20 (20p13).^[3]

See also

• List of cutaneous conditions