Artifactual cleft between the epidermis and the lichenoid infiltrate
(Max-Joseph space) noticed.
(17) On light microscopy, parameters strongly suggestive of the diagnosis of MF include; atypical intra-epidermal lymphocytes which are surrounded by halos, Pautrier's micro abscesses, disproportionate epidermotropism, epidermal lymphocytes larger than dermal lymphocytes, hyperconvoluted intraepidermal lymphocytes aligned within the basal layer and the papillary dermal fibrosis within a lichenoid infiltrate. (13,15,16,18)
(21) These include exocytosis with paucity of spongiosis, solitary lymphocytes lined up along the basal layer, epidermal lymphocytes larger than dermal lymphocytes and papillary dermal fibrosis within a lichenoid infiltrate. While Smoller concluded that haloed lymphocytes proved to be the most robust discriminator of MF from non-MF on multivariate analysis studies.
Damage to basal layer, resulting in formation of colloid bodies and pigmenting incontinence, suggests a possible relationship of EDP to lichen planus pigmentosus.15,3 It is true that lichen planus pigmentosus has a more pronounced lichenoid infiltrate
and its lesions have a greater predilection to be located in the exposed areas but the occasionally described coexistence of the two conditions suggests that they are related.
A lichenoid infiltrate
was present in 11 of the specimens (48%), whereas psoriasiform epidermal hyperplasia was present in only 8 (35%).
Histopathologically, PNP is most often seen as suprabasal acantholysis, dyskeratosis, and cellular autoimmune phenomena: vacuolar interface change and lichenoid infiltrates
. DIF reveals intercellular IgG and/or C3 deposits, sometimes in combination with their linear deposits along the basement membrane (20).