Lymphocytes in Sweet syndrome: A potential diagnostic pitfall

Abstract

Awareness of the lymphocytic component of SS is important to avoid diagnostic errors, especially in subcutaneous lesions of SS, in which the lymphocytic infiltrate predominates in the upper parts of the dermis, while the typical neutrophilic infiltrate may be seen only in the deeper dermis and subcutis. The lymphocytic component may potentially help to differentiate lesions of SS from neutrophilic urticarial dermatosis, which has not been reported to contain a significant lymphocytic population.

Neutrophilic Dermatosis of the Hands with Palmar Involvement and Predominant Lymphomononuclear Cell Infiltration

“…In a recent case report, Peteln et al described a case of NDH with perivascular and interstitial lymphocytic infiltration where biopsy was taken from a 1- to 2-day-old pustule. [ 7 ] Similar histopathological findings were also corroborated by Kazlouskaya et al [ 8 ] and Jordaan[ 9 ] in a few cases of SS. Jordaan postulated that the lymphocytes appeared initially, generated lymphokines that attracted the neutrophils, resulting in a more robust neutrophilic component in the more developed elevated lesions.…”

Neutrophilic dermatosis of the dorsal hands (acral Sweet syndrome) with predominantly lymphocytic dermal infiltrate

“…In neutrophilic dermatoses, predominantly lymphocytic infiltrate in the dermis with a minor component of granulocytes has been reported in SS, at the edge of a PG ulcer, and in a new nodule in a patient with NDDH, whereas neutrophils predominated in a biopsy from a fully developed, large plaque…”

Vasculitis and Neutrophilic Dermatoses and Related Disorders

“…35 (A, B) Levamisole-induced vasculitis/vasculopathy, an angiocentric mixed infiltrate that includes neutrophils, with changes of both vasculitis and thrombo-occlusion of the small vessels of the papillary dermis (H&E stain). (Taken by Joel Tjarks, Dermatology Department, Geisinger Medical Center, USA) lymphocytic infiltrate (Kazlouskaya and Junkins-Hopkins 2018) and subcutaneous lobular involvement (Fig. 40).…”