Position paper on diagnosis and treatment of atopic dermatitis

The diagnosis of atopic dermatitis (AD) is made using evaluated clinical criteria. Management of AD must consider the symptomatic variability of the disease.

Atopic dermatitis: from new pathogenic insights toward a barrier-restoring and anti-inflammatory therapy

Recent published work on atopic dermatitis focusing on the pathogenesis and epidemiology, which have a direct effect on treatment, is presented.

Systemic therapy of atopic dermatitis in children and adults

Systemic therapy is required in patients with severe atopic dermatitis (AD) refractory to adequate topical therapy. The aim of a systemic therapy is the rapid and efficient improvement of skin symptoms and pruritus in acute exacerbation and/or the long-term control of severe chronic disease. A number of immunosuppressive and immunomodulating substances are available that may efficiently reduce skin inflammation and thus lead to a relief of symptoms including pruritus. The excellent effects of cyclosporine as short-term as well as maintenance therapy have been documented in several studies in children and adults. Furthermore, other immunosuppressive substances such as azathioprine, mycophenolate mofetil and methotrexate are effective in patients with moderate to severe AD. Intravenous immunoglobulins and γ-interferon exert immunomodulatory effects and thus may improve severe AD. Biological agents are a new approach in AD therapy since they may specifically target cells, cytokines or mediators involved in the pathogenesis of AD.

Patient-Oriented SCORAD (PO-SCORAD): a new self-assessment scale in atopic dermatitis validated in Europe

BACKGROund: Patient-oriented medicine is an emerging concept, encouraged by the World Health Organization, to greater involvement of the patient in the management of chronic diseases. The Patient-Oriented SCORing Atopic Dermatitis (PO-SCORAD) index is a self-assessment score allowing the patient to comprehensively evaluate the actual course of atopic dermatitis (AD), using subjective and objective criteria derived mainly from the SCORAD, a validated AD severity clinical assessment tool.

Atopic dermatitis - from new pathophysiologic insights to individualized therapy

Recently, important novel insights into the complex pathophysiology of atopic dermatitis (AD) have been gained. However, in most cases the therapy of AD is limited to base line therapy with emollients combined with symptomatic, rather general immunosuppressive treatment approaches of the flare-ups. Latest research findings together with experiences from daily clinical practice, which support the concept that a combination of general disease features together with specific trigger factors in the individual patients drive the disease, might be helpful for a subclassification of patients with AD based on the most relevant pathophysiologic modifications. Subclassification of patients with AD seems indispensable to introduce rationale-based, individualized treatment approaches of AD, which target specific modified pathways. In this review, we provide an overview about a selection of pathophysiologic pathways, which hold promise to represent targets of such therapeutic approaches in the near future.

Establishment of diagnostic criteria for feline nonflea-induced hypersensitivity dermatitis

Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD.

Role of the environment in the development of canine atopic dermatitis in Labrador and golden retrievers

Canine and human atopic dermatitis are multifaceted diseases whose clinical development may be influenced by several factors, such as genetic background, environment, secondary infections, food and psychological effects. The role of the environment has been extensively examined in humans but remains unclear in dogs. The aim of this study was to examine environmental factors in two genetically close breeds, Labrador and golden retrievers. Using standard criteria, atopic dogs in Switzerland and Germany were selected and compared with healthy individuals. Information on environmental factors was collected using a 46-question survey encompassing date and place of birth, way of life at the breeder's and owner's home, food and treatments. Univariate and multivariate logistic regression were used to assess the association between potential risk factors and disease status. The following parameters were associated with an increased risk of disease development: living in a shed during puppyhood, adoption at the age of 8-12 weeks and washing the dog regularly. In contrast, the following factors were associated with a lower risk: living in a rural environment, living in a household with other animals and walking in a forest. These associations do not prove causality but support the primary hypothesis that certain environmental factors may influence the development of canine atopic dermatitis. Further studies are warranted to confirm these results and conclusions.

[Juvenile sterile granulomatous dermatitis and lymphadenitis in the dog]

Juvenile sterile granulomatous dermatitis and lymphadenitis is a rare immune-mediated skin disease in young dogs. History, signalment, diagnostics, treatment, and outcome in 10 dogs are described. The age ranged from 8 - 36 weeks. The lymph nodes were enlarged in all dogs, especially the mandibular and prescapular lymph nodes. Systemic signs including fever were present in 8 dogs. Seven dogs suffered from blepharitis and painful edema of the muzzle with hemorrhagic discharge, pustules and papules. Cytology of pustules and lymph node aspirates revealed a pyogranulomatous inflammation. In 7 cases the diagnosis of juvenile sterile granulomatous dermatitis and lymphadenitis was confirmed by histology. Nine dogs were treated with prednisolone (0.5 - 1.25 mg/kg BID), H2-receptor antagonists and analgetics; all dogs were treated with antibiotics. Four dogs were treated with eye ointment containing antibiotics and glucocorticoids. The prednisolone dosage was tapered over 3 - 8 weeks. One dog had a relapse.

New drug targets in atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disorder characterized by eczematous skin lesions, pruritus and typical histopathological features. T cells are thought to play a key role, but B cells might also participate in the pathogenesis of AD. In two investigator-initiated pilot studies, we studied the effects of B cell depletion by monoclonal anti-CD20 antibody therapy or a reduction of activated T cells by LFA3-IgG fusion protein on moderate-to-severe AD. All patients treated with either rituximab or alefacept showed an improvement of their skin symptoms with a sustained effect after treatment. In both studies, histological alterations, such as spongiosis, acanthosis and dermal infiltrate, including T and B cell numbers, dramatically improved and the expression of IL-5 and IL-13 was reduced after therapy. Upon rituximab therapy, allergen-specific IgE levels were not altered and total serum IgE levels only slightly decreased. According to recent studies, neutralizing B and T cells products such as IgE or IL-5 might be effective in subgroups of patients with AD.

Missing C-terminal filaggrin expression, NFkappaB activation and hyperproliferation identify the dog as a putative model to study epidermal dysfunction in atopic dermatitis

Filaggrin loss-of-function mutations resulting in C-terminal protein truncations are strong predisposing factors in human atopic dermatitis (AD). To assess the possibility of similar truncations in canine AD, an exclusion strategy was designed on 16 control and 18 AD dogs of various breeds. Comparative immunofluorescence microscopy was performed with an antibody raised against the canine filaggrin C-terminus and a commercial N-terminal antibody. Concurrent with human AD-like features such as generalized NFKB activation and hyperproliferation, four distinctive filaggrin expression patterns were identified in non-lesional skin. It was found that 10/18 AD dogs exhibited an identical pattern for both antibodies with comparable (category I, 3/18) or reduced (category II, 7/18) expression to that of controls. In contrast, 4/18 dogs displayed aberrant large vesicles revealed by the C-terminal but not the N-terminal antibody (category III), while 4/18 showed a control-like N-terminal expression but lacked the C-terminal protein (category IV). The missing C-terminal filaggrin in category IV strongly points towards loss-of function mutations in 4/18 (22%) of all AD dogs analysed.