Dual diagnosis of histiocytoid Sweet syndrome and anti-neutrophil cytoplasmic antibody-associated vasculitis, APR 2022.
"Histiocytoid Sweet syndrome (H-SS) is a rare variant of acute febrile neutrophilic dermatosis. It is frequently associated with hematologic malignancies but has also been associated with certain inflammatory states. Here we report a case of concurrent anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis and H-SS diagnoses."
"Our patient had a very rare combination of H-SS skin lesions in the setting of ANCA proteinase-3 granulomatosis with polyangiitis glomerulonephritis."
ADDITIONAL NOTE.
HISTIOCYTOID SWEET'S SYNDROME: In Sweet’s syndrome, mature white blood cells called neutrophils accumulate in the tissues. In histiocytoid Sweet’s syndrome, immature myeloperoxidase-positive cells and not mature neutrophils can be seen (mainly M2-like CD 163+macrophages). Myeloperoxidase is an enzyme that’s abundantly expressed in neutrophils.
The immature cells in histiocytoid Sweet’s syndrome can be mistaken for histiocytes; immune cells that destroy foreign substances and help fight infection. Sometimes, real or authentic histiocytes may also be present.
ANCA-ASSOCIATED VASCULITIS: Neutrophilic dermatoses, including Sweet's syndrome, have previously been recognized in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis. ncbi.nlm.nih.gov/pmc/articl...