Lymphocytic Vasculitis

1. as a sequential manifestation in the setting of a leukocytoclastic vasculitis

(B cell- and complement-mediated; helper T-lymphocytes?)

2. as perivenular infiltrates (T-cell infiltrate)

S8C34bVA7b-1: Two variations of lymphocytic vasculitis are listed.

Tissue Damage: Lymphocytic Vasculitis

(delayed hypersensitivity)

1. perivenular accummulations of mononuclear cells

a. related to distribution of antigen

b. sensitized cells proliferate in adventitia of vessels, or

c. pass from lumen through wall of vessels to collect in adventitia and contribute to infiltrates

d. infiltrate histologically precedes most recognizable patterns of tissue damage

S8C34bVA7b-2: Perivenular infiltrates of lymphoid cells might be cited as a prototypic pattern, expressive of cell-mediated immune reactions.

Vasculitis

(T-lymphocyte)

1. perivenular island

2. infiltrates in sites of antigen localization

3. invasive and destructive

4. cytotoxic and lytic

5. transformed lymphocytes (Lutzner cells)

6. absence of plasma cells

7. may be vasodestructive

8. pityriasis lichenoides as model

9. lymphomatoid papulosis as a model

S8C34bVA7b-3: Features of “lymphocytic vasculitis” of a cell-mediated, immune reaction are listed. In addition, models, in which patterns of a lymphocytic vasculitis are represented, are offered as suggestions; in the suggested models, frank necrosis of vessels occasionally is a feature.

Lymphocytic Capillaritis

1. histologic requisites

a. relatively confined to papillary dermis

b. thickened vessels

c. swollen endothelium

d. may be associated with lichenoid patterns at dermal- epidermal interface

S8C34bVA7b-4: The designation, capillaritis, gives recognition to infiltrates of inflammatory cells that are relatively restricted in distribution to the perivascular spaces of vessels of the papillary dermis, including the vessels of the dermal papillae. The concept has utility in defining the histologic patterns commonly encountered in the setting of the progressive pigmented purpuras.