A child with fever presents with multiple tender erythematous skin lesions. On microscopic examination the skin lesions are seen to have neutrophilic infiltration in the dermis. What is the diagnosis

Sweet syndrome is a neutrophilic dermatosis. Skin lesions consist of multiple, dusky, erythematous, tender papules or nodules that coalesce to form irregular plaques. There is fever and neutrophilic leukocytosis. In pyoderma gangrenosum is a rare , non infectious , neutrophilic dermatosis commonly associated with underlying systemic disease. From illustrated synopsis of dermatology and sexually transmitted diseases neena khanna 5th edition page no 202, 203