Case Presentation
An 11-year-old girl with known history of psoriasis vulgaris presented complaining of a few asymptomatic skin-colored raised lesions over both arms and shoulders appeared 2 months before. More recently she noticed the development of itchy, flaky, erythematous patches over these areas. Clinical examination revealed few discrete skin-coloured umbilicated papules 0.3 × 0.3 cm in size over the left shoulder and the infraclavicular regions sourranded by discrete erythematous plaques with silvery-white scales. Dermoscopic examination of the psoriatic plaque revealed pinkish-white homogenous areas with white scales and regular dotted vessels (Figure 1).
Figure 1.
(A) Multiple discrete erythematous scaly plaques around the central umbilicated papules of molluscum contagiosum. (B) Close-up view of molluscum contagiosum (black star) with surrounding psoriatic plaque (black arrow). (C) Dermoscopy of the molluscum contagiosum showing a whitish yellow papule with homogenous amorphous structure in the center (white arrow). (D) Psoriatic plaque: pinkish white homogenous areas with white scales and regular dotted vessels (blue star).
Teaching Point
Aclinical diagnosis ofpsoriatic isomorphic response surrounding the preexisting molluscum contagiosum was made (1). The patient was managed with needle extirpation of the molluscum contagiosum along with topical steroids for the psoriatic plaques, which resulted in the resolution of symptoms.
Footnotes
Competing Interests: None.
Authorship: All authors have contributed significantly to this publication.
Funding: None.
References
- 1.Ji YZ, Liu SR. Koebner phenomenon leading to the formation of new psoriatic lesions: evidences and mechanisms. Biosci Rep. 2019;39(12):BSR20193266. doi: 10.1042/BSR20193266. [DOI] [PMC free article] [PubMed] [Google Scholar]