Lymphomatoid Papulosis in Pediatric Patient: A Case Report

ABSTRACT
Lymphomatoid papulosis is a low-grade malignant skin lymphoma. It is a rare lymphoproliferative disease clinically characterized by generalized chronic, recurrent and self-limited CD30+ positive papules and nodules. It courses along with a mixed inflammatory infiltrate of eosinophils, neutrophils, histiocytes and plasma cells that in histopathology can adopt a variety of at least six patterns named from A to F and it is possible to see more than one variable in one patient; it can eventually progress to a primary skin lymphoma of large anaplastic cells.

Keywords: Lymphomatoid Papulosis; Mycosis fungoides; Lymphoproliferative disorders; Cutaneous lymphoma.

Abbreviations:
LP: Lymphomatoid papulosis;
ALCL: Primary cutaneous anaplastic large cell lymphoma;
PLEVA: Pityriasis lichenoides et varioliformis acuta;
PLC: Pityriasis lichenoides chronica;
MF; Mycosis fungoides;
EBV: Epstein-Barr virus

INTRODUCTION
Lymphomatoid papulosis (LyP) is a self-regressing, chronic, CD30 T-cell lymphoproliferative disease characterized by recurrent, and spontaneously remitting papulonodular or necrotic lesions that appear anywhere on the body but are frequently disseminated¹. It is classified alongside primary cutaneous anaplastic large cell lymphoma, in the group of T-cell proliferations expressing CD30.

In roughly 10–20% of the patients, it is linked to an increased risk of secondary lymphomas, including mycosis fungoides and CD 30+ large T-cell lymphoma (LTCL). This disorder's most remarkable aspect is that its aggressive histological characteristics that closely resemble lymphoma, are not concordant with the benign clinical course and spontaneous remission². Due to the increased risk of developing non-Hodgkin lymphoma, lifelong follow-up is justified. We report the case of a 9-year-old presenting with recurring papulo-necrotic lesions over face, trunk, and extremities.

CASE PRESENTATION
We received a 9 year-old girl with a history of 18 months of recurrent papular lesions which progressed slowly and appeared mostly in the limbs, treated with emollients and topical and systemic steroids without total improvement. The lesions had changed morphology and generalized. At the physical examination she presented a dermatosis disseminated to trunk and limbs characterized by multiple erythematous papules and papulo-vesicles ranging from 3 to 10 mm of diameter, some ulcerated with hemorrhagic crusts on its surface (Figure 1). she also presented some very pruritic nodules of approximately 5 mm accompanied by mild xerosis without signs of over infection. The clinical differential diagnosis included pityriasis lichenoides chronica versus lymphomatoid papulosis. Cutaneous biopsy of the right leg was performed revealing an infiltrate extending from the papillary to the reticular dermis in smaller extent, composed mainly by lymphocytes, some histiocytes, neutrophils and eosinophils, as well as a smaller number of large atypical lymphocytes (Figure 2). Immunohistochemistry stained strong CD4+ expression in approximately 90% in a wedge shape. Additionally, epidermo and folliculotropic CD30+ cells (Figure 3), with moderately strong perinuclear and cluster expression (Figure 4) appeard. Normally, CD4+ is dominant in CD30+ lymphoproliferative diseases, thus the diagnosis of Papulosis Lymphomatoid Type A was made. The patient started methotrexate 10 mg weekly which lead to the involution of lesions leaving post-inflammatory scars. After 1 year, treatment was deescalated to tacrolimus 0.1% proactive twice weekly and emollients in lesions. The patient continues follow up every 3 months.

    
Figure 1. Multiple erythematous papules and papulo vesicles of several mm of diameter, some ulcerated, covered with hemorrhagic crusts over trunk and extremities(A, B). 


Figure 2. Infiltrate that extends from the papillary dermis to the reticular dermis in smaller extent, composed mainly by lymphocytes, histiocytes some neutrophilus and accompanyed by einophilus, and a smaller number of large atypical lymphates.
Courtesy Dra. Johanna Brito - LunaPiel


Figure 3. Strong expression CD4+ approximately 90% in a wedge shape, in addition to epidermotropism and folliculotropisms of cells
Courtesy Dra. Johanna Brito - LunaPiel 


Figure 4. Moderately strong perinuclear and cluster CD30+ expression
Courtesy Dra. Johanna Brito – LunaPiel