CORRECT DIAGNOSIS:

Erythema dyschromicum perstans

DISCUSSION:

Erythema dyschromicum perstans (EDP) is a chronic hyperpigmentation disorder characterized by asymptomatic blue-gray patches with slightly elevated erythematous borders in the early stages. Usually, it presents as a symmetrical eruption involving the face, neck, trunk, and proximal extremities, although there have been reports of asymmetric unilateral EDP affecting the lower extremity. EDP can affect persons of all ages, however, it usually presents before the age of 40. Women tend to be affected more than men, and there is a predilection for intermediate to darker skin types, in particular Latin Americans. The etiology of EDP remains unknown; several predisposing factors have been suggested: ammonium nitrate ingestion, whipworm infection, oral ingestion of radiographic contrast material, following treatment of hookworm infection, HIV infection as well as immunological and genetic associations.

TREATMENT:

There is no standard treatment for EDP. Past treatments have included sun protection, topical retinoids, topical and systemic corticosteroids, keratolytics, hydroquinone, antibiotics, isoniazid, griseofulvin, chemical peels, and laser therapy. There are also reports of using Clofazimine and Dapsone, however, given the wide side effect profiles of these medications, the risks versus benefits should be weighed carefully.

REFERENCES:

Bolognia, J. L., Jorizzo, J. L., & Rapini, R. P. (2008). Dermatology (pp. 941-942). Mosby.

Osswald, S. S., & et al. (2001). Erythema dyschromicum perstans: A case report and review. Cutis, 68(1), 25-28. [PMID: 11418264]

Baranda, L., & et al. (1997). Involvement of cell adhesion and activation molecules in the pathogenesis of erythema dyschromicum perstans (ashy dermatitis): The effect of clofazamine therapy. Archives of Dermatology, 133(3), 325-329. https://doi.org/10.1001/archderm.133.3.325 [PMID: 9058336]

Correa, M. C., & et al. (2007). HLA-DR association with the genetic susceptibility to develop ashy dermatosis in Mexican mestizo patients. Journal of the American Academy of Dermatology, 56(4), 617-620. https://doi.org/10.1016/j.jaad.2006.09.029 [PMID: 17240360]

Bahadir, S., & et al. (2004). Erythema dyschromicum perstans: Response to dapsone therapy. International Journal of Dermatology, 43(3), 220-222. https://doi.org/10.1111/j.1365-4632.2004.01937.x [PMID: 15086366]