Dermatitis 23 (4): 153 - 157, 2012. doi: 10.1097/DER.0b013e318260d5a0 Symptoms and Signs of Nummular Dermatitis Plaques and patches of nummular dermatitis are erythematous and scaly, typically intensely pruritic, and are coin-shaped and well-demarcated but not sharply.