Congenital anonychia - Nail and Distal Digit
Patients with nail-patella syndrome, ectodermal dysplasia, anonychia–lymphedema, DOORS syndrome, and Iso-Kikuchi syndrome have anonychia and severe skeletal defects. Dyskeratosis congenita is characterized by bone marrow failure, reticulate pigmentation, nail dystrophy, and oral leukoplakia. Anonychia can be seen in children. Absence of nail may be confined to thumbs and great toes or on the fifth finger in Coffin-Siris syndrome. Use of alcohol, morphine, and antiepileptics in pregnancy has been associated with hyponychia and anonychia.
Anonychia has been linked to chromosome 20p13. Homozygous or compound heterozygous mutations in the gene encoding R-spondin 4 (RSPO4), a secreted protein implicated in Wnt signaling, have been identified, suggesting that RSPO4 has a crucial role in nail morphogenesis.
Q84.3 – Anonychia
23610003 – Anonychia
- Stevens-Johnson syndrome (SJS) / toxic epidermal necrolysis (TEN)
- Lichen planus – Nail plate atrophy, pterygium, and hyponychia / anonychia can be seen.
- Alopecia areata – There may be hyponychia / anonychia with shallow regular pitting.
- Cutaneous T-cell lymphoma (Sézary syndrome) – The presence of onychauxis, anonychia, distal notching, and onychoschizia distinguishes nail changes in Sézary syndrome from nail psoriasis.
- Acral porokeratosis
- Junctional epidermolysis bullosa
- Isolated abnormality (dominant, recessive, or sporadic), often combined with skeletal or systemic defects.