Differential diagnosis of lymphomatoid papulosis in children: a review and case series

Lymphomatoid papulosis is a rare T-cell lymphoproliferative disorder that primarily affects the skin. It is a chronic, recurrent condition that sometimes regresses spontaneously. Lymphomatoid papulosis is typically manifested by recurrent papules ranging in number from a few to several hundred. Lymphomatoid papulosis has similarities with other lymphoproliferative, inflammatory, and infectious diseases, which makes diagnosis verification challenging. Differential diagnosis between lymphomatoid papulosis and primary cutaneous lymphoma, as well as systemic cutaneous anaplastic large cell lymphoma, mycosis fungoides, and T-cell lymphoma/leukemia, is required. Comprehensive differential diagnosis is especially relevant in pediatric patients, given that skin rashes in children are frequently represented by nodular or necrotic lesions, as well as erythematous and scaling patches, which may correspond to a wide range of medical conditions. There is currently no standard of care for lymphomatoid papulosis; the treatment strategy depends on the severity of lesions, ranging from case follow-up to glucocorticoid, anticancer, or targeted therapy.

This paper presents differential diagnosis criteria for lymphomatoid papulosis, based on the authors’ own experience and published data. The paper describes clinical and morphoimmunohistochemical characteristics for each type of the disease. A special emphasis was placed on selecting the treatment strategy. Two patients were followed up after diagnosis verification, but did not receive active treatment. The third patient, who had severe lesions and did not respond to topical treatment, received targeted therapy with brentuximab vedotin, which was highly effective.

Dermatologists, hematologists, and pathologists must work together to diagnose lymphomatoid papulosis promptly, and the treatment strategy must take into account all clinical features.