What is the most common cause of migrating necrotizing dermatitis?

Migrating necrotizing dermatitis is primarily associated with glucagonoma, which is a type of tumor that arises from the alpha cells of the pancreas and leads to elevated levels of glucagon. This condition is characterized by skin lesions that develop due to the high levels of glucagon causing a catabolic state, which predisposes the animal to various infections. The skin lesions typically manifest as painful, necrotic, and often ulcerative lesions that may appear in multiple areas of the body, hence the term "migrating."

In the context of glucagonoma, the necrotizing dermatitis is linked to the underlying metabolic derangements caused by the excessive production of glucagon, which can impair normal healing and immune function, leading to opportunistic infections and subsequent dermatitis.

Understanding the pathophysiology behind glucagonoma is crucial for recognizing its clinical manifestations, including migrating necrotizing dermatitis. The presence of skin lesions in conjunction with other signs of glucagonoma, such as diabetes mellitus, weight loss, and the characteristic glucagon levels, can aid in diagnosis and management.