Dermatology Online Journal

Background: Histiocytoid Sweet syndrome is an uncommon variant in which the dermal infiltrate is composed of mononuclear cells with a histiocytic appearance that represent immature myeloid cells. Giant cellulitis-like Sweet syndrome is a recently described variant characterized by relapsing widespread giant lesions.

Purpose: We report a unique patient with histiocytoid giant cellulitis-like Sweet syndrome and review the current literature on histiocytoid Sweet syndrome and giant cellulitis-like Sweet syndrome.

Material and Methods: We reviewed PubMed for the following terms and have reviewed the literature: histiocytoid, giant cellulitis-like, and Sweet syndrome.

Results: Six individuals, including our patient, have been reported with giant cellulitis-like Sweet syndrome; four had obesity, two had a hematologic malignancy, and one had breast cancer. Histiocytoid Sweet syndrome has been reported in association with autoimmune diseases, infection or inflammation, inflammatory bowel disease, malignancies, medications, and other conditions.

Conclusions: Histiocytoid Sweet syndrome is a rare variant of Sweet syndrome, often associated with malignancy. Giant cellulitis-like Sweet syndrome has been reported in six individuals; four of the patients were obese and three of the patients had an associated cancer. Our patient had histiocytoid giant cellulitis-like Sweet syndrome-associated myelodysplastic syndrome/myeloproliferative disorder. The diagnosis of histiocytoid Sweet syndrome or giant cellulitis-like Sweet syndrome should prompt the clinician to consider additional evaluation for a Sweet syndrome-associated malignancy.