Face infiltrated Plaques/Nodules
The clinical differential diagnosis of a patient presenting with facial plaques and or nodules consists of acute discoid lupus erythematosus (DLE) and tumid lupus erythematosus (TLE), Jessner benign lymphocytic infiltration of the skin (JBLI), lymphocytoma cutis (also known as pseudolymphoma of Spiedler and Fendt), sarcoidosis, granuloma faciale (GF), follicular mucinosis, and B-cell lymphoma (BCL). In endemic areas, lupus vulgaris, Leishmania recidivans, subcutaneous and systemic fungal infection, and extra nodal NK cell lymphoma nasal type may be considered.
The histological findings in DLE, sarcoidosis, and GF are characteristic. Differentiation between tumid LE and JBLI may be difficult. Some authors consider tumid LE and JBLI to be the same disorder. Others have suggested that JBLI represents a benign lymphocytic proliferation that may be viewed as a perivascular form of lymphocytoma cutis. Follicular mucinosis may be primary or secondary to mycosis fungoides. Histological evaluation is essential in differentiating between the two types. Differentiation between lymphocytoma cutis and BCL is generally easy; sometimes immunohistochemical and genetic studies are needed.