An assessment of the use of antihistamines in the management of atopic dermatitis

BACKGROUND

Antihistamines are often used to treat pruritus associated with atopic dermatitis (AD) despite lack of evidence for their efficacy. The American Academy of Dermatology does not recommend the general use of antihistamines in the management of AD, although the value of short-term sedating antihistamine use for insomnia secondary to itch is recognized.

OBJECTIVE

To assess the use of sedating and nonsedating antihistamines for AD in 2003-2012.

METHODS

The National Ambulatory Medical Care Survey provided data on physician visits in 2003-2012. Sedating and nonsedating antihistamine use was identified at visits for AD.

RESULTS

There were 990,000 annual visits for AD. Antihistamines were prescribed for AD in a significant proportion of visits across physician specialties (16%-44%). Dermatologists and pediatricians primarily used sedating antihistamines (58%-70%), whereas the majority of family/general practitioners, internists, and other specialists prescribed nonsedating antihistamines for AD (55%-100%) LIMITATIONS: We were limited by the accuracy of AD diagnosis and medication recording.

CONCLUSIONS

Antihistamines are widely used for the treatment of AD. There is no high-level evidence to suggest that nonsedating antihistamines reduce itch in patients with AD or that sedating antihistamines provide benefit in controlling AD symptoms (except perhaps sleep and AD comorbidities, such as allergic rhinitis).

TSLP, IL-31, IL-33 and sST2 are new biomarkers in endophenotypic profiling of adult and childhood atopic dermatitis

BACKGROUND

Recent years have seen growing interest in identifying new biomarkers in atopic dermatitis (AD) that could serve as indicators of disease severity and predictors of treatment response.

OBJECTIVES

We compared serum levels of thymic stromal lymphopoietin (TSLP), interleukin(IL)-31, IL-33 and soluble(s)ST2 in AD patients and healthy controls, investigated the possible correlation with disease severity, investigated if other atopic comorbidities could play a role, and assessed their potential as biomarkers in AD.

METHODS

Using standard enzyme-linked immunosorbent assay techniques, we measured target serum levels in 71 adults and 61 children with AD, and 31 adult controls. We characterized our cohort by disease severity, radioallergosorbent test status concerning both dietary and inhalant allergens, and anamnestic reports of food allergy, concomitant allergic asthma and/or allergic rhinitis.

RESULTS

Serum levels of TSLP, IL-31 and IL-33, but not sST2, were significantly elevated in AD patients compared with controls. In AD patients, both IL-31 and IL-33 serum levels were higher in children than in adults, while the opposite was the case for sST2. We observed no correlation between disease severity and any of the investigated targets. While serum TSLP levels were unaffected by concomitant allergies and atopic comorbidities, serum levels of IL-31, IL-33 and sST2 were affected to a small extent. We found a positive correlation between TSLP, IL-31 and IL-33, and an inverse relationship between IL-33 and sST2.

CONCLUSIONS

The studied targets hold little potential as indicators of disease severity. The serum values of our targets show robustness against atopic comorbidities, allergies and changes in disease severity. This robustness strengthens their potential use in biomarker-based stratification and could be instrumental in identifying subgroups and predicting the possible benefit of therapeutic and prevention approaches.

The histamine H4 receptor mediates inflammation and pruritus in Th2-dependent dermal inflammation

The role of histamine H(4) receptor (H(4)R) was investigated in a T-helper type 2 (Th2)-cell-mediated mouse skin inflammation model that mimics several of the features of atopic dermatitis. Treatment with two specific H(4)R antagonists before challenge with FITC led to a significant reduction in ear edema, inflammation, mast cell, and eosinophil infiltration. This was accompanied by a reduction in the levels of several cytokines and chemokines in the ear tissue. Upon ex vivo antigen stimulation of lymph nodes, H(4)R antagonism reduced lymphocyte proliferation and IL-4, IL-5, and IL-17 levels. One explanation for this finding is that lymph nodes from animals dosed with the H(4)R antagonist, JNJ 7777120, contained a lower number of FITC-positive dendritic cells. The effect of H(4)R antagonism on dendritic cell migration in vivo may be an indirect result of the reduction in tissue cytokines and chemokines or a direct effect on chemotaxis. In addition to anti-inflammatory effects, JNJ 7777120 also significantly inhibited the pruritus shown in the model. Therefore, the dual effects of H(4)R antagonists on pruritus and Th2-cell-mediated inflammation point to their therapeutic potential for the treatment of Th2-mediated skin disorders, including atopic dermatitis.