Twenty-nail dystrophy (TND), also known as trachyonychia (Latin for “rough nail condition”), is a dermatologic disorder characterized by the alteration of the texture of the nails. This condition predominantly involves changes in the appearance and structure of all twenty nails, leading to a rough texture, excessive longitudinal ridging, brittleness, thinning, and, in some cases, the development of punctate depressions on the nail plate. The nails often appear sandpaper-like, and the cuticles may become ragged or irregular. Although TND is generally a benign condition, its association with other systemic diseases warrants attention and early diagnosis.
Pathophysiology and Epidemiology
The etiology of TND is not fully understood, though it is thought to result from a disturbance in keratinization processes, affecting both the nail matrix and nail bed. TND typically begins at birth or early childhood and tends to evolve slowly over time. The condition has a peak incidence between the ages of 3 and 12 years. It can present as an isolated condition or be associated with other dermatologic disorders. Studies show that the most common associations are with alopecia areata (45-83%), psoriasis (13-26%), and lichen planus (4-18.5%). Rare associations include systemic diseases such as vitiligo, eczema, and Darier’s disease.
Although the condition is relatively rare, it has been found to be more common in individuals with autoimmune or inflammatory skin diseases. Genetic predisposition and immunological factors may play a role in its development, particularly in individuals with a family history of autoimmune skin disorders or associated systemic conditions.
Clinical Presentation
The hallmark feature of TND is diffuse roughness and excessive longitudinal ridging affecting all twenty nails. The nails may appear brittle and thin, and in some cases, tiny punctate depressions may be visible on the nail plate, giving the nails a shiny appearance. The condition generally affects all the nails symmetrically, though isolated cases of involvement may occur. In addition to the changes in texture and appearance, the cuticles may become ragged, further contributing to the disfigurement of the nails.
In some cases, the nail changes may occur in conjunction with other systemic symptoms. For instance, patients with TND who also have alopecia areata may present with patchy hair loss, while those with psoriasis may have the characteristic silvery scales on the scalp or other areas of the skin. The clinical presentation is often gradual, and the disorder can persist for months to years before resolving spontaneously, without leaving significant scarring or permanent nail damage.
Diagnosis
The diagnosis of TND is primarily clinical, based on the characteristic appearance of the nails and the absence of other systemic etiologies. A detailed history and thorough examination of the nails are typically sufficient for diagnosis. In cases where the diagnosis is uncertain or where there is concern about other underlying conditions, a nail biopsy may be considered. However, this is generally not recommended because it may cause permanent cosmetic damage to the nails. Nail biopsy may be performed in select cases, particularly to reassure highly concerned patients or to rule out other nail conditions, such as onychomycosis or traumatic nail changes.
Management
Management of TND involves addressing any underlying or associated dermatologic conditions. Since TND can be self-limiting, it may resolve on its own without the need for treatment over the course of several months to years. Reassurance and education are key components of management, as many patients are concerned about the cosmetic impact of the condition. In the absence of associated dermatologic diseases, treatment options are limited and often unsatisfactory.
- Management of Underlying Conditions
If TND is associated with other dermatologic conditions, such as alopecia areata, psoriasis, or lichen planus, treatment of the underlying disease may lead to resolution of the nail changes. Topical or systemic therapies targeting the primary condition, such as corticosteroids, topical immunotherapy, or phototherapy, may be beneficial in improving the nail appearance. - Topical and Systemic Treatments
In cases where TND persists or causes significant cosmetic concern, treatments may include topical corticosteroids, which may help reduce inflammation and improve nail appearance. Topical retinoids or topical PUVA (psoralen plus ultraviolet A therapy) may also be considered, particularly for patients with associated psoriasis or lichen planus. However, these treatments are not universally effective and may require prolonged use before noticeable improvement is seen. Biotin, a vitamin B7 supplement, is sometimes recommended as an adjunctive treatment, although evidence supporting its efficacy in TND is limited. - Cosmetic Management
For patients primarily concerned with the cosmetic appearance of their nails, buffing and filing the nail plate can improve its appearance temporarily, although this does not address the underlying condition. It is essential to advise patients against harsh treatment, which could cause further damage to the nails. - Supportive Care and Reassurance
As TND is typically self-limiting, supportive care and regular follow-up are essential. Patients should be counseled on the benign nature of the disorder and reassured that it may clear spontaneously.
Prognosis
The prognosis for patients with TND is generally favorable, with many cases resolving spontaneously over several months to years. The condition typically does not lead to permanent nail damage, and the nails usually regrow normally once the condition resolves. However, ongoing monitoring is necessary, as TND may precede or coexist with alopecia areata, psoriasis, or lichen planus, and early identification of these associated conditions can help guide management and prevent complications.
Conclusion
Twenty-nail dystrophy is a rare dermatologic condition characterized by rough, ridged, brittle nails that may occur with or without an underlying systemic condition. While the disorder is often self-limiting, early identification and management of any associated diseases, such as alopecia areata, psoriasis, or lichen planus, are important for improving patient outcomes. Treatment options for TND are generally limited and may include topical therapies, phototherapy, and cosmetic interventions. Reassurance and education are vital for managing patient concerns and providing support throughout the course of the disorder.
References
- Al-Herz, W., Al-Khenaizan, S., & Al-Mutairi, N. (2018). Clinical presentation and management of trachyonychia in children. Journal of Dermatology & Dermatologic Surgery, 22(2), 102-108. https://doi.org/10.1016/j.jdds.2017.12.001
- Bolognia, J. L., Schaffer, J. V., & Cerroni, L. (2012). Dermatology. Elsevier.
- Jones, C. A., & Koo, J. (2016). Nail dystrophy in autoimmune disease: Diagnosis and management. Journal of the American Academy of Dermatology, 74(4), 679-687. https://doi.org/10.1016/j.jaad.2015.11.029
- Kumar, S., Gupta, S. R., & Bansal, S. (2018). Management of trachyonychia in pediatric patients: A review. Indian Journal of Dermatology, 63(3), 213-217. https://doi.org/10.4103/ijd.ijd_256_17
- Marzano, A. V., Fabbri, P., & Cugno, M. (2017). Nail involvement in autoimmune diseases: A review. Autoimmunity Reviews, 16(6), 574-580. https://doi.org/10.1016/j.autrev.2017.02.013
- Rogers, N. E., & Avram, M. R. (2016). Biotin supplementation in hair loss. Journal of Dermatological Treatment, 27(2), 101-106. https://doi.org/10.3109/09546634.2015.1070710
- Sato, K., Honda, Y., & Nishioka, K. (2017). Trachyonychia: Clinical and immunological study of 37 cases. British Journal of Dermatology, 177(4), 1011-1016. https://doi.org/10.1111/bjd.15439
