Annular Lichenoid Dermatitis of Youth: Report of Six New Cases with Review of the Literature

Abstract

Background: Annular lichenoid dermatitis of youth (ALDY) is an uncommon disease clinically reminiscent of morphea, annular erythema or mycosis fungoides. Objective: To describe the histological and clinical features of a small series of patients with ALDY and to review the literature. Patients: We describe the clinical and histological features of six patients (age range 7-79 years) with asymptomatic erythematous macules and patches with a red-brownish border and central hypopigmentation, mostly distributed on the groin and flanks. Histologically, all cases showed lichenoid dermatitis limited to the tips of rete ridges, with many intraepidermal CD8+ and some CD4+ T cells. T cell receptor rearrangement was absent in all cases. A total of 44 patients with a consistent clinical and histological picture have been described. The disease is sensitive to topical and/or systemic corticosteroids. Conclusions: ALDY is a unique lichenoid dermatitis for whose diagnosis a clinical-pathological correlation is essential. The disease typically affects young patients, more rarely adults and elderly.

Annular lichenoid dermatitis of youth—Recurrent case of rare skin disease treated with cyclosporine

“…Sensitization to various antigens has been investigated and excluded in one adult patient (de la Torre, Flórez, & Fernandez‐Redondo, ). Testing for autoimmunity, infections, or allergies in patients and their families did not find any relevant etiologic factors (Annessi et al, ; Di Mercurio, Gisondi, Colato, Schena, & Girolomoni, ). A triggering factor that activates T cell‐mediated cytotoxic reaction against keratinocytes, remains an open question.…”

“…However, many potential causing factors for lichenoid dermatoses (such as drugs, contact with chemicals, allogenic bone‐marrow or stem cell transplantation, UV exposure, persistent viral reactions, and neoplastic diseases) have not been confirmed in patients with ALDY. Although the name ALDY indicates that lesions appear mostly in children, and young adults, ALDY cases in adults, have been reported (Di Mercurio et al, ). It is important to differentiate ALDY from other distinctive dermatoses (Table ).…”

“…Histologically, the main difficulty is to differentiate ALDY from mycosis fungoides (MF), especially hypopigmented type. Typical features of ALDY are infiltration of lymphocytes, limited to the tips of rete ridges and massive apoptosis of keratinocytes conferring a square‐shaped appearance (Annessi et al, ; de la Torre et al, ; Debois et al, ; Di Mercurio et al, ). The lymphocytic immunophenotype is characterized by mixed T cell infiltrate, consisting of CD4+ T cells in the dermis, and mainly intraepidermal CD8+ T cells.…”

Pediatric CD8+/CD56+ mycosis fungoides with cytotoxic marker expression: A variant with indolent course

“…MF may indeed be easily confused with eczema, psoriasis, lupus erythematous, tinea corporis, pityriasis lichenoides chronic, and lichen aureus, and its hypopigmented variant may resemble pityriasis alba or vitiligo . Another disorder which enters in differential diagnosis with MF is annular lichenoid dermatitis of youth (ALDY) . Furthermore, in children many dermatologists may hesitate to obtain biopsies and sometimes several histological exams are required to prove the diagnosis, especially after topical corticosteroids application.…”

“…Primary cutaneous epidermotropic γ/δ T‐cell lymphoma with aberrant expression of CD8 may be distinguished by expression of TCR‐γ, prominent involvement of the subcutaneous tissue and usually very poor prognosis. CD8+ MF may enter differential diagnosis both clinically and histologically with ALDY, which is a lichenoid dermatitis with marked keratinocyte apoptosis limited to the rete ridges, and absence of both epidermotropism and clonal TCR rearrangement …”