Sweet syndrome on a patient with autoimmune hepatitis on azathioprine and CMV infection

Insights Into the Pathogenesis of Sweet's Syndrome

Sweet's syndrome, also known as Acute Febrile Neutrophilic Dermatosis, is a rare inflammatory condition. It is considered to be the prototype disease of neutrophilic dermatoses, and presents with acute onset dermal neutrophilic lesions, leukocytosis, and pyrexia. Several variants have been described both clinically and histopathologically. Classifications include classic Sweet's syndrome, malignancy associated, and drug induced. The cellular and molecular mechanisms involved in Sweet's syndrome have been difficult to elucidate due to the large variety of conditions leading to a common clinical presentation. The exact pathogenesis of Sweet's syndrome is unclear; however, new discoveries have shed light on the role of inflammatory signaling, disease induction, and relationship with malignancy. These findings include an improved understanding of inflammasome activation, malignant transformation into dermal infiltrating neutrophils, and genetic contributions. Continued investigations into effective treatments and targeted therapy will benefit patients and improve our molecular understanding of inflammatory diseases, including Sweet's syndrome.

Case Report of Sweet’s Syndrome Associated With Autoimmune Hepatitis

Autoimmune hepatitis is a subtle diagnosis that has many diverse clinical presentations. It has been reported in the literature to occur concomitantly with pyoderma gangrenosum, a neutrophilic dermatosis. Sweet’s syndrome is another neutrophilic dermatosis and has been reported to be associated with autoimmune hepatitis in only 2 previous cases: 1 idiopathic and 1 drug induced. Here we report a third case in a 24-year-old woman diagnosed with Sweet’s syndrome in association with autoimmune hepatitis, documenting a possible trend between neutrophilic dermatoses and autoimmune hepatitis. The patient presented with a history of fever and tender, erythematous plaques on her legs. Skin biopsy of a plaque confirmed histiocytoid Sweet’s syndrome. Initial laboratory investigations revealed elevated transaminases, and liver biopsy confirmed autoimmune hepatitis. This case suggests autoimmune hepatitis should be considered as an association when investigating a patient with Sweet’s syndrome.