Unusual CD8 positive lymphomatoid papulosis in childhood.

Lymphomatoid Papulosis (LyP) is a rare disorder characterized by a self-healing eruption of papules and small nodules with histopathologic features mimicking a cutaneous T-cell lymphoma CD 30+. We report a 15-year-old girl with CD8+ T-cells, an unusual phenotype in this disease. The clinical and pathological differential diagnoses are discussed.

Evidence linking atopy and staphylococcal superantigens to the pathogenesis of lymphomatoid papulosis, a recurrent CD30+ cutaneous lymphoproliferative disorder.

BACKGROUND: Primary cutaneous CD30+ lymphoproliferative disorders (CD30CLPD) are the second most common type of cutaneous T cell lymphoma (CTCL) and include lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large cell lymphoma (pcALCL). Case reports and small patient series suggest an association of CD30CLPD with atopic disorders. However, the prevalence of atopy in patients with CD30CLPD in retrospective studies depends on patients' recall which is not always reliable. More objective criteria of atopy include evidence of skin reactivity to allergens (positive prick test) and evidence of allergen-specific IgE in serum. This study was undertaken to test the hypothesis that atopy is prevalent in patients with CD30CLPD using serologic criteria of allergen-specific IgE antibodies to aeroallergens and Staphylococcal aureus enterotoxin superantigens (SSAgs). METHODS: We tested serum samples of CD30CLPD for common IgE-specific airborne allergens with the Phadiatop test, which if positive, is regarded as serologic evidence of atopy in adults. Sera were also tested for IgE antibodies reactive to three Staphylococcal enterotoxins with superantigenic properties (SSAg-IgE). Control sera were obtained from adult subjects evaluated for rhino-sinusitis and a negative Phadiatop test. Patients' history of an atopic disorder was obtained by retrospective chart review. FINDINGS: Nearly 50% of patients with the most common LyP types (A and C) had a positive Phadiatop test for allergic sensitization to common airborne allergens, and total serum IgE (IgE-t) was increased compared to non-atopic controls. At the IgE antibody concentration generally used to define serologic atopy (≥ 0.35 kUA/L), 8/31 (26%) samples of CD30CLPD and 7/28 (25%) samples of LyP were reactive to at least one SSAg-IgE compared to 3/52 (6%) control specimens (P = 0.016 and P = 0.028, respectively). TSST1-IgE was detected in 7 (23%) specimens of CD30CLPD, often together with SEB-IgE; SEA-IgE ≥ 0.35 kUA/L was not detected. For control specimens, TSST1-IgE exceeded the 0.35 kUA/L threshold in 3 (6%) specimens. CONCLUSIONS: Patients with LyP types A and C have serologic evidence of atopy against common airborne antigens and SSAgs when compared to control adult subjects who had rhino-sinusitis and a negative Phadiatop test for aero-IgEs. Serologic evidence of atopy exceeded that determined by LyP patients' personal history. The findings support our hypothesis that an atopic diathesis may contribute to the pathogenesis of the most common types of LyP (A and C).

T-cell clonality of peripheral blood lymphocytes in patients with lymphomatoid papulosis.

Six patients with lymphomatoid papulosis demonstrated a clonal T-cell population in skin lesions by polymerase chain reaction methods. Two of these patients showed identical T-cell clones in their peripheral blood T cells as well. In one case, the clone persisted in the blood despite clearing of skin lesions with methotrexate.