Dermoscopy can differentiate scalp psoriasis from seborrheic dermatitis

January 01, 0001

Dermoscopy can differentiate scalp psoriasis from seborrheic dermatitis

Psoriasis and seborrheic dermatitis are common erythematous-squamous dermatoses that may present with scaly erythematous patches on the scalp. Owing to the similar clinicopathological features of these dermatoses, their differentiation poses a diagnostic challenge, particularly when the lesions on the scalp are isolated. This was a retrospective observational study by researchers from Korea to evaluate the characteristic dermoscopic features of scalp psoriasis and seborrheic dermatitis. The study included a total of 96 patients with lesions; these patients were recruited from 2 tertiary teaching hospitals in Korea (Pusan National University Hospital and Kyungpook National University Hospital). Among these, 55 patients had scalp psoriasis, and 41 patients had seborrheic dermatitis.

The most significant dermoscopic features of scalp psoriasis were red dots and globules, twisted red loops, and glomerular vessels. In contrast, seborrheic dermatitis was characterized by arborizing vessels and atypical red vessels with the absence of red dots and globules. Featureless areas devoid of any particular vascular patterns were also frequently observed in seborrheic dermatitis. Dermoscopic findings of red lines and other vascular patterns were not considered useful for differentiation because these were uncommon features in both diseases. Although scales were observed commonly in both the diseases, there was no significant difference in the frequency and characteristics of the scales when they were observed using dermoscopy.

The researchers concluded: "Our study shows that the investigation of vascular patterns by using dermoscopy can be valuable for the clinical diagnosis and differentiation of scalp psoriasis and seborrheic dermatitis."

This can be a helpful add-on to history, distribution and other clinical features.

For the full abstract, click here.

British Journal of Dermatology published online 14 December 2010
© 2010 British Association of Dermatologists
Dermoscopy can be useful in differentiating scalp psoriasis from seborrheic dermatitis. G.W. Kim, H.J. Jung, H.C. Ko et al. Correspondence to yung-Soo Kim: [email protected]

Category: S. Skin. Keywords: dermoscopy, differentiating, scalp, psoriasis, seborrhoeic dermatitis, retrospective observational study, journal watch.
Synopsis edited by Dr Stephen Wilkinson, Melbourne, Australia. Posted on Global Family Doctor 28 January 2011

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