2013.4-26.Red

RED LANULA

Patricia Chang¹, Mónica Vanesa Vásquez Acajabón²

Corresponding author:  Patricia Chang, MD PhD    e-mail: pchang2622@gmail.com

How to cite an article: Chang P, Vásquez Acajabón MV. Red Lunula. Our Dermatol Online. 2013; 4(4): 555-556.

Case 1

Male patient, 80 years old hospitalized due to tumor on his left neck to diagnosis, his nails were seen by chance when he was waiting for his lung X ray examination. He had not noticed anything on his fingernails, we observed red lunula on both thumb nails (Fig. 1, 2). Personal history: controlled diabetes mellitus and high blood pressure

 

 

Figures 1. Panoramic view of red lunula at both thumbs.

Figures 2. Close up of the onychophaty lesions.

Case 2

Male patient, 65 years old hospitalized due to urinary tract infection , his nails also was seen by chance when he was waiting for his clinical evaluation by infectologist. He had not noticed the change in color of his fingernails. Clinical examination showed red color at the lunulas of both thumbnails (Fig.3). Personal history non contributory. The red lunula is an uncommon nail dyschromia; all the cases we have seen until now have been by chance. The lunula is the white half-moon–shaped area located at the base of fingernails and toenails; it is the only visible part of the nail matrix, which is responsible of producing keratin to form the nail plate. Anomalies of shape, form or color in lunula may be an indication of injury or serious disease, as a deficiency or infection [1,2]. Color anomalies, known as lunula dyschromias, can be confluent or spotted, or can be characterized by longitudinal colored bands. Colors with a red or blue tinge can be indicative of heart or lung disease, rheumatoid arthritis or hypertension. Dark hues can indicate conditions such as infection or heavy metal intoxication. More subtle tones may be a sign of conditions like respiratory illness, vitamin deficiency or anemia [2]. Red lunula is associated with rheumatoid arthritis, systemic lupus erythematosus (20% of the patients with SLE have been reported to have this abnormality) [3], cardiac failure, hepatic cirrhosis, lymphogranuloma venereum, pulmonary disease, carbon monoxide poisoning, among others [4]. It may be idiopathic, and it also has been reported in patients with dermatological diseases, such as chronic urticaria, psoriasis vulgaris, lichen sclerosis and atrophic or alopecia areata [1,4]. It can affect all the nails or only part of them [5]. Red lunula can be classified into three kinds: a complete form- in which the all lunula is erythematous – an incomplete form- where the proximal zone is red and in the distal zone appears a white arrow band, proximal to the pink nail bed- and the third one, a mottled form that can be observed in rheumatoid arthritis [5]. It mainly involves the thumbs where the lunula is usually clearly visible [5,6]. The pathogenesis of red lunula remains undetermined [4,6]. However it has been described as a possible result of the increment of arteriolar blood flow, a vasodilatory capacitance phenomenon, or changes in the optical properties of the overlying nail, so that normal blood vessels become more apparent [4].

 

Figures 3. Red lunula on thumbnails.

REFERENCES

1. Chang P, Cuyuch C: Lúnula roja. Reporte de dos casos. DCMQ 2010;8:198 -200.

2. Cohen PR: The lunula. J Am Acad Dermatol. 1996;34:954 -6.

3. Tunc SE: Nail changes in connective tissue diseases. J Eur Acad Dermatol Venereol. 2007;21:497.

4. Wilkerson MG, Wilkin JK: Red lunula revisited: A clinical and histopathology examination. JAAD. 1989;20:453-7.

5. Pérez BT, Sánchez BA, Marinero SE, Arsuaga CA, Polimon IO, Fernández PL: Lúnulas rojas en alopecia areata. Med Cutan Iber Lat Am. 2010;38:207-9.

6. Baran R: The Red Nail – Always Benign? Actas Dermosifiliogr. 2009;100:106-13.