Acute neutrophilic dermatosis (Sweet syndrome) is a benign self-limited disease in adults. A child with apparent evolution of acute neutrophilic dermatosis to postinflammatory cutis laxa and elastolysis then developed fatal vascular involvement. One other patient with postinflammatory cutis laxa with aortic regurgitation and sudden fatal unrecognized occlusive coronary arterial disease is discussed. If cardiovascular symptoms or signs develop during the course of Sweet syndrome or postinflammatory cutis laxa, a thorough investigation is warranted to rule out potentially fatal coronary arterial disease. Coronary bypass surgery may be the only effective treatment for the severely fibrosed proximal coronary arterial system.