Pink is not always pretty

Pink skin nodules usually demand a biopsy to find the cause. The smooth surface shown here indicates the problem is in the dermis rather than the epidermis, where scale would occur. Nodules can be due to infiltrates of cells, substances or organisms in the dermis. A purple or deep pink colour usually suggests an infiltrate of neutrophils, as in Sweet’s syndrome, or of lymphocytes, as in post insect bite reactions, lymphomas and leukaemias. This was a B cell lymphoma diagnosed by incisional biopsy and special staining. The specimen was also sent for culture, as deep fungal infections such as dermal sporotrichosis can present like this.