A 19-year-old woman presented with persistent nodular pigmented lesions on the left side of her lower back area that had been present since the age of 3 months. The lesions were sometimes pruritic and caused occasional paresthesia. Treatment with cryotherapy had been unsuccessful.
Examination of the skin revealed a cluster of pink to purple, firm, nontender nodules, some with peripheral hyperpigmentation, on the left lower back area (Figure 1). A biopsy specimen stained with hematoxylin-eosin is shown in Figure 2 and Figure 3. A section stained for factor XIIIa antigen is shown in Figure 4.
Green C. Multiple Nodules on the Back. Arch Dermatol. 1999;135(3):341-b-346. doi:10-1001/pubs.Arch Dermatol.-ISSN-0003-987x-135-3-dof0399