Red lunulae explained

Red lunulae is characterized by a dusky erythema confined to the lunulae, as has been reported in association with alopecia areata.^[1] It is most commonly seen on the thumbnail.

Signs and symptoms

Red lunulae describes erythema that either totally or partially takes the place of that structure's typical white tone.^[2] It is typically visible on the thumbnail, where the lunula is most noticeable.^[3]

Causes

Increased arteriolar blood flow, the vasodilatory capacitance phenomenon, and modifications to the optical characteristics of the nail plate overlaying the blood vessel, which accentuates the normal blood vessels, have all been proposed as possible causes of the red lunula.^{[4] [5]}

Disorders associated with red lunulae include systemic lupus erythematosus, reticulosarcoma, psoriasis, hepatic cirrhosis, lymphogranuloma venereum, rheumatoid arthritis, alopecia areata, cardiac failure, and carbon monoxide poisoning.^[4]

History

Terry originally reported red lunulae in patients in 1954.^[6]

See also

• Lunula
• Spotted lunulae

Further reading

• Roest . Y . Middendorp . H . Evers . A . Kerkhof . P . Pasch . M . Nail Involvement in Alopecia Areata: A Questionnaire-based Survey on Clinical Signs, Impact on Quality of Life and Review of the Literature . Acta Dermato Venereologica . Medical Journals Sweden AB . 98 . 2 . 2018 . 0001-5555 . 10.2340/00015555-2810 . 212–217 . none. 2066/190317 . free .
• Jorizzo . Joseph L. . GonzalezD . Emilio B. . Daniels . Jerry C. . Red lunulae in a patient with rheumatoid arthritis . Journal of the American Academy of Dermatology . Elsevier BV . 8 . 5 . 1983 . 0190-9622 . 10.1016/s0190-9622(83)70085-x . 711–714 . none.

Notes and References

1. James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. .
2. Morrissey . Kelly A. . Rubin . Adam I. . Histopathology of the red lunula: new histologic features and clinical correlations of a rare type of erythronychia . Journal of Cutaneous Pathology . 40 . 11 . 2013 . 0303-6987 . 10.1111/cup.12218 . 972–975.
3. Baran . R. . The Red Nail – Always Benign? . Actas Dermo-Sifiliográficas . Elsevier BV . 100 . 2009 . 0001-7310 . 10.1016/s0001-7310(09)73175-8 . 106–113.
4. Wilkerson . Michael G. . Wilkin . Jonathan K. . Red lunulae revisited: A clinical and histopathologic examination . Journal of the American Academy of Dermatology . Elsevier BV . 20 . 3 . 1989 . 0190-9622 . 10.1016/s0190-9622(89)70057-8 . 453–457.
5. Cohen . Philip R. . Red lunulae: Case report and literature review . Journal of the American Academy of Dermatology . Elsevier BV . 26 . 2 . 1992 . 0190-9622 . 10.1016/0190-9622(92)70037-g . 292–294.
6. Terry . Richard . RED HALF-MOONS IN CARDIAC FAILURE . The Lancet . Elsevier BV . 264 . 6843 . 1954 . 0140-6736 . 10.1016/s0140-6736(54)91932-7 . 842–844.