Tibial Lymphoplasmacytic Plaque: A New, Illustrative Case of a Recently and Poorly Recognized Benign Lesion in Children

Abstract

Tibial lymphoplasmacytic plaque (TLP) is a recently recognized clinicopathological entity affecting children and is characterized by a linear, reddish brown plaque on the leg with a dense dermal lymphoplasmacytic infiltrate. No effective treatments are available for this lesion of unknown etiology and its course is chronic. We report a new case in which, for the first time, a causative factor (insect bite) is strongly suspected. The clinical and pathological features of TLP may be misleading for the uninformed dermatologist or pathologist. Therefore, we would like to draw attention to this very distinctive clinicopathological presentation in order to help them recognize it easily and prevent it from being misdiagnosed as an infectious disease or, above all, a cutaneous lymphoma. We will discuss the relationship between TLP and linear acral pseudolymphomatous angiokeratoma of children, a variant of pseudolymphoma localized on acral sites in children which may share some of TLP’s histopathological features.

Lymphoplasmacytic plaque in children: Case report and literature review

“…Initially described in the literature as “pretibial lymphoplasmacytic plaque,” LPP is a benign chronic dermatosis without systemic involvement that primarily affects children.…”

“…Lymphoplasmacytic plaque in children (LPP) is a rare cutaneous disease. It has been recently proposed as an emerging clinicopathologic entity characterized by a dense dermal lymphoplasmacytic infiltrate with or without epithelioid granulomas and is considered a plasma cell pseudolymphomatous process of unknown origin . These lesions are clinically determined by reddish‐brown papules and plaques, which are typically found on the lower limbs, especially on the anterior shin.…”

Pathologic Diagnosis of Cutaneous Lymphomas

“…Secondary cutaneous plasmocytoma could be excluded by staging procedures. Rare, but important differential diagnoses are vegetating herpes virus infections in HIV patients, 90 lymphoplasmacytoid plaque, 91,92 and cutaneous plasmocytosis. 93 These entities can show a plasma cell-rich infiltrate, but the plasma cells are polyclonal in contrast to most cases of PCMZL.…”

A case of lymphoplasmacytic plaque in children

“…Primary cutaneous plasma cell infiltrates are rare in children and are mostly reactional, in response to infection. A recently recognized entity has been described under the name of ‘lymphoplasmacytic plaque in children’ or ‘isolated benign primary cutaneous plasmacytosis in children’ or ‘pretibial lymphoplasmacytic plaque’ . They have characteristic clinical and histopathological features and no systemic manifestations.…”

“…Lymphoplasmacytic plaque in children is a recently recognized entity, also reported under the name of isolated benign primary cutaneous plasmacytosis in children or pretibial lymphoplasmacytic plaque. Less than 20 cases have been reported so far . The clinical presentation is very distinctive with isolated reddish brown to violaceous well‐defined plaques with small papules, sometimes scaling, appearing in children from age 7–15.…”