A new review published in the International Journal of Dermatology reveals a troubling gap in dermatologic research: patients with skin of color (SoC) are significantly underrepresented in studies of inflammatory nail disorders. This lack of inclusion may be contributing to delayed diagnoses and poorer outcomes for these patients.
Researchers analyzed 60 studies covering 16 inflammatory nail disorders and over 12,000 patient cases. Only three studies explicitly documented skin phototypes. Many relied on the country of origin of authors or patient cohorts to infer SoC representation, a method the authors say is insufficient.
The review found that patients with SoC often experience longer times to diagnosis and more severe disease, particularly in conditions like nail psoriasis (NP), which is also a diagnostic marker for psoriatic arthritis. Clinical signs of NP and other disorders may appear differently or less prominently in darker skin, complicating diagnosis.
Longitudinal melanonychia and nail plate discoloration—features more common in SoC—are not typically seen in lighter skin types. Without adequate visual documentation and understanding of these differences, clinicians may miss or misinterpret key symptoms.
The authors call for more inclusive research and better documentation of skin phototypes in dermatology literature. “Enhanced awareness and understanding of inflammatory nail disorders in SoC will improve diagnostic accuracy, treatment outcomes, and overall health equity,” they wrote.
See: “Skin of Color: Representation in Dermatology Literature” (May 30, 2025)
