Sublingual immunotherapy efficacy in patients with atopic dermatitis and house dust mites sensitivity: a prospective pilot study.

BACKGROUND: Specific subcutaneous immunotherapy (SCIT) with house dust mite (HDM) preparation has recently been shown to improve eczema in patients with atopic dermatitis (AD). So far, there is less data regarding efficacy and safety of specific sublingual immunotherapy (SLIT) in patients with AD. STUDY AIM: To evaluate in an open non-controlled, non-randomized pilot trial the effect of SLIT with HDM allergen extracts preparation (SLITone, ALK Abellò Italy) on SCORAD in adult patients with mild-moderate AD. PATIENTS AND METHODS: 86 Subjects (53 females and 33 males) between 3 and 60 years of age with AD and IgE-proved (Class > 2) HDM sensitization were enrolled after their informed consent in the trial. Exclusion criteria were severe asthma and treatment with systemic or high potent topical corticosteroids or immunosuppressant agents. Patients were treated with SLIT (Dermatophagoides pteronyssinus and Dermatophagoides farinae extracts: SLITone, ALK-Abellò) for at least 12 months. SCORAD was evaluated at baseline and after 12 months of treatment. RESULTS: Baseline SCORAD value, mean +/- SD, was 43.3 +/- 13.7 (range 15-84). After 1 year of SLIT, mean +/- SD, SCORAD value was reduced to 23.7 +/- 13.3 (range: 0-65) (p = 0.0001; unpaired t-test vs. baseline). This was a 46% reduction in SCORAD in comparison with baseline value. A significant improvement, defined as a SCORAD reduction of > 30%, was observed in 51 out of 86 patients (59%). In 5 patients (5.8%) SCORAD values did not change at the end of the observation period. In 30 patients (35%) the SCORAD reduction after SIT was

The potential role of allergen-specific sublingual immunotherapy in atopic dermatitis.

Atopic dermatitis is a chronic inflammatory skin disease associated with increasing prevalence, morbidity, and cost in developed Western countries. Frequently associated with respiratory allergy during adulthood, atopic dermatitis often represents the first phenotypic appearance of atopy in early childhood when the allergic 'march' starts and progressively moves toward food allergy, asthma, and rhinitis. At present, a consistent body of evidence supports the view that atopic dermatitis may represent the skin compartmentalization of a systemic allergic inflammation. Lymphocytes infiltrating early lesional skin express a T helper (Th) 2 pattern of cytokine secretion (increased levels of interleukin [IL]-4 and/or IL-13 and decreased levels of interferon-gamma) as well as the typical Th2-type chemokine receptor CCR4, specific to the thymus and activation-regulated chemokines. Keratinocytes from patients with atopic dermatitis produce thymic stromal lymphopoietin, a novel cytokine that supports the early lymphocyte development in mouse models, and activates dendritic cells involved in the pathogenesis of allergic diseases in humans. Increased levels of circulating hemopoietic precursor cells have been reported in atopic dermatitis, as in allergic asthma and rhinitis. Furthermore, the recognition of CD34+ hemopoietic precursor cells, and evidence for cellular differentiation/maturational events occurring within atopic dermatitis skin lesion infiltrates, are consistent with the recent reinterpretation of the Th2/Th1 paradigm, where Th2 cells appear to belong to the early stages and Th1 to the ultimate stages of a linear, rather than divergent, pattern of lymphoid differentiation. This more detailed understanding of the immunologic derangements contributing to the atopic dermatitis pathogenesis has led to growing interest in allergen-specific immunotherapy for the disease. Due to the complexity intrinsic to atopic dermatitis and the lack of consensus-based guidelines for standardized outcome measure, only eight studies are available in the literature for a qualitative evaluation of this treatment approach. Two of these studies were double blind and placebo controlled, and six were cohort studies. Immunotherapy was found to be effective in one controlled study and five observational reports. Uncertain results were provided by one low-powered, controlled study, and negative outcomes were raised by a unique study performed with oral immunotherapy, which is not an effective route of mucosal allergen administration. Thus, more efficacy studies are required before immunotherapy could be recommended for the routine treatment of atopic dermatitis. Allergen-specific sublingual immunotherapy, given its excellent safety profile and ability to interfere with the systemic aspects of allergic inflammation, appears a good potential candidate for the pathogenetic treatment of the disease.