Red lunulae L60.8

The lunula is the white crescent-shaped area at the base of the fingernails and toenails and the only visible part of the nail matrix.

A red lunula can occur as a complete homogeneous discoloration (the entire lunula is red), as an incomplete variant (only the proximal lunula is red), or as a speckled, spot-shaped form.

Red lunula is associated with a number of dermatological and systemic diseases. It is one of the rarer manifestations of lichen planus (LP): Furthermore, the occurrence of red lunulae has been associated with the following diseases:

• Systemic lupus erythematosus (diffuse form of red lunulae).
• Alopecia areata
• Heart failure
• Cirrhosis of the liver
• Psoriasis (punctate form of red lunulae)
• Rheumatoid arthritis (Jorizzo JL et al. 1983)
• Carbon monoxide poisoning
• Twenty-nail dystrophy (Twenty-nail dystrophy)
• Malignant lymphatic systemic diseases

No evidence of neovascularization.

Red lunulae are thought to result from increased arteriolar blood flow, a vasodilator capacitance phenomenon, or changes in the optical properties of the overlying nail so that normal blood vessels are more prominent. See also under erythronychia (red nail).

1. Bergner T et al (1992) Red lunulae in severe alopecia areata. Acta Derm Venereol 72:203-205.
2. Chelidze K et al (2018) Nail changes in alopecia areata: an update and review. Int J Dermatol 57:776-783.
3. Cohen PR (1992) Red lunulae: case report and literature review. J Am Acad Dermatol 26:292-294.
4. Ji C et al (2021) Challenge of nail psoriasis: an update review. Clin Rev Allergy Immunol 61:377-402.
5. Jorizzo JL et al (1983) Red lunulae in a patient with rheumatoid arthritis.
6. J Am Acad Dermatol 8:711-714.
7. Kaur I et al (2020) Intraoperative onychoscopy and histopathological correlation of red lunula in nail lichen planus: a case series. Clin Exp Dermatol 45: 884-887.
8. May Yet al.(2018) A case of red lunulae after haematopoietic stem cell transplantation. Eur J Dermatol 28:407-409.
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10. Wilkerson MG et al (1989) Red lunulae revisited: a clinical and histopathologic examination. J Am Acad Dermatol 20:453-457.
11. Wollina U et al (1999) Lupus erythematosus-associated red lunula. J Am Acad Dermatol 41:419-421.