Pautriers microabscess is seen in –
**Core Concept**
Pautrier's microabscess is a characteristic histopathological feature of mycosis fungoides, a type of cutaneous T-cell lymphoma. It represents an intraepidermal collection of atypical lymphocytes, which are typically CD4+ T-cells, that invade and destroy the surrounding keratinocytes.
**Why the Correct Answer is Right**
Pautrier's microabscess is a diagnostic hallmark of mycosis fungoides. The atypical lymphocytes within the microabscess are often large and have hyperchromatic nuclei, and they may exhibit features of apoptosis. The presence of these microabscesses is typically seen in the epidermis, and they can be accompanied by a surrounding inflammatory infiltrate. The CD4+ T-cell nature of the lymphocytes within the microabscess is confirmed through immunohistochemical staining.
**Why Each Wrong Option is Incorrect**
**Option A:** While pityriasis lichenoides is a skin condition that involves lymphocytes, it does not typically exhibit the characteristic intraepidermal collections of atypical lymphocytes seen in Pautrier's microabscess.
**Option B:** Lichen planus is an autoimmune skin condition that involves a T-cell mediated inflammatory response, but it does not typically exhibit Pautrier's microabscesses.
**Option C:** Psoriasis is a chronic autoimmune skin condition that involves an inflammatory response, but it does not typically exhibit Pautrier's microabscesses.
**Clinical Pearl / High-Yield Fact**
Pautrier's microabscess is a critical diagnostic feature of mycosis fungoides, and it should be considered in the differential diagnosis of any patient with a history of skin lesions that are resistant to treatment. A biopsy of the affected skin showing Pautrier's microabscess can confirm the diagnosis of mycosis fungoides.
**Correct Answer:** D. Mycosis fungoides.