Dermatitis Herpetiformis

• Chronic itchy clusters of blisters.
• Linked to underlying gluten enteropathy (coeliac disease).

Dermatofibroma

• Benign lesion.
• Firm elevated nodules.
• Usually history of trauma.
• Lesion consists of histiocytes, blood vessels and fibrotic changes.

Pyogenic granuloma

• Overgrowth of blood vessels.
• Red nodules.
• Usually follow trauma.
• May mimic amelanotic melanoma.

Acanthosis nigricans

• Brown to black, poorly defined, velvety hyperpigmentation of the skin.
• Usually found in body folds such as the posterior and lateral folds of the neck, the axilla, groin, umbilicus, forehead, and other areas.
• The most common cause of acanthosis nigricans is insulin resistance, which leads to increased circulating insulin levels. Insulin spillover into the skin results in its abnormal increase in growth (hyperplasia of the skin).