Clinical Reviews in Allergy

Skin lesions are frequent manifestations of underlying systemic conditions, including systemic autoimmune vasculitis. In particular, anti-neutrophil cytoplasmic antibodies (ANCA) are associated with distinct forms of vasculitis characterized by inflammatory cell infiltration of the walls of small and medium-sized vessels leading to vascular destruction and tissue necrosis. ANCA-associated vasculitis is rare and systemic diseases, which can be classified based on different distribution of vascular inflammation and presence or absence of granulomatosis and asthma. Despite their diversities, ANCA-associated vasculitis, namely microscopic polyangiitis, granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis, can all display a broad variety of cutaneous manifestations, which can appear during the course of the disease or even as first sign at the time of onset. Different skin manifestations might coexist in the same patient and occur in different occasions during the course of the vasculitis. Thus, a deep knowledge of the spectrum of skin lesions as part of ANCA-associated vasculitis is mandatory for a correct diagnostic process, whenever cutaneous vasculitis is suspected. Due to this broad variety of manifestations, the diagnosis of skin involvement in ANCA-associated vasculitis is very challenging and it must be supported by a detailed medical history, accurate physical examination, specific histopathological analysis of skin biopsy and the presence of ANCA serology. In this review, we focus on the cutaneous manifestations that can develop in the context of ANCA-associated vasculitis, detailing the clinical features, the histopathological aspects as well as the direct immunofluorescence studies for each of the three conditions. Moreover, we acknowledged the differential diagnoses that must be ruled out in the diagnostic process and the main therapeutic approaches available for treatment of ANCA-associated vasculitis.

Cercarial dermatitis (swimmer's itch) is a common non-communicable water-borne disease. It is caused by penetration of the skin by larvae (cercariae) of schistosomatid flukes and develops as a maculopapular skin eruption after repeated contacts with the parasites. The number of outbreaks of the disease is increasing, and cercarial dermatitis can therefore be considered as an emerging problem. Swimmer's itch is mostly associated with larvae of the bird schistosomes of Trichobilharzia spp. Recent results have shown that mammalian infections (including man) manifest themselves as an allergic reaction which is able to trap and eliminate parasites in the skin. Studies on mammals experimentally infected by bird schistosome cercariae revealed, however, that during primary infection, parasites are able to escape from the skin to the lungs or central nervous system. This review covers basic information on detection of the infectious agents in the field and the clinical course of the disease, including other pathologies which may develop after infection by cercariae, and diagnosis of the disease.

It is astounding to consider that virtually, every textbook of physiology in every medical school in the world does not include a chapter on immunology. On the other hand, virtually, in every textbook in internal medicine, immunology and immune response overlaps with every tissue and every organ. Indeed, historically, the concept of the immune response was recognized primarily in the setting of allergy and/or anaphylaxis. Indeed, the very concepts of infection, microbiology and host protection are relatively new sciences. In fact, it was little more than 100 years ago when washing hands became what is now coined “standard of care.” How different it is in 2013, where one finds Handi Wipes for shoppers to use at grocery stores to protect themselves from the flora on shopping cart handles. Autoimmunity is even a newer concept without going into the well-known history of Paul Ehrlich and hemolytic anemias, the LE cell, and the beginning field of serology (and rheumatoid factor discovery). It is apparent that our understanding of autoimmunity has become linked hand-in-glove with new tools and investigational probes into serology and, more recently, the cellular immune response. With such discoveries, a number of key observations stand out. Firstly, there are a great deal more autoantibodies than there are autoimmune diseases. Second, there are a great deal more of autoimmune diseases than was believed in 1963 on the occasion of the publication of the first textbook of autoimmune diseases. Third, autoimmune diseases are, for the most part, orphan diseases, with many entities afflicting too few patients to excite the financial limb of pharmaceutical companies. In this special issue, we have grouped a number of papers, many of which were presented at the recent Congress of Autoimmunity that focus on issues that are not commonly discussed in autoimmunity. It reminds us that due to the ubiquitous nature of the innate and adaptive response, that there are a large number of diseases that have either an inflammatory and/or specific autoimmune response, we have to keep an open eye because everything is potentially autoimmune until proven otherwise.

Latex allergy is quite common in exposed subjects. Questionnaires can bring useful information but can also be misleading because such symptoms as itching may only result from irritation. Thus, in any case, skin tests with latex must be performed. Latex allergy occurs mainly in young people exposed to latex products because of their occupation or because of repeated surgery. Atopy is a strong predisposing factor.

We hypothesize that Type 1 diabetes of humans and NOD mouse results from non-MHC genes, which determine susceptibility to T-cell autoimmunity. MHC class II alleles (and perhaps class I) determines the tissue targeted by these T-cells (DQ8/DQ2 Type 1 diabetes and Addison's disease, DQ2 or DQ8 for celiac disease). The high propensity for islet beta cells to be the target of autoimmunity we believe is the result of a peculiarity of the insulin B-chain peptide, such that it is a dominant beta cell-specific autoantigen. In the NOD mouse, autoreactive T-cells show a restricted Vα repertoire. The ability of selected class II molecules to prevent disease may relate to effects of these molecules (I-E, DQB1*0602, and so forth) on the T-cell repertoire. With improving assays for autoantibodies and T-cell autoimmunity and the availability of transgenic mouse, we believe that the aforementioned hypotheses can be thoroughly tested.

Beta-lactam antibiotics are the most commonly reported drug allergy in adults and children. More than 95% of those with reported allergy labels to beta lactams are not confirmed when subjected to allergy testing. Beta lactam antibiotics are associated with a wide spectrum of immediate and delayed drug hypersensitivity reactions. The latency period to symptoms and clinical presentation aids in the causality assessment. Risk stratification based on diagnosis and timing then allows for appropriate management and evaluation. Skin prick testing, intradermal testing and oral challenge are well established for evaluation of immediate reactions. Delayed intradermal testing, patch testing and oral challenge can also be considered for evaluation of mild to moderate delayed reactions. Cross-reactivity between beta-lactams appears to be driven most commonly by a shared R1 side-chain. Standardized algorithms, protocols and pathways are needed for widespread implementation of a pragmatic and effective approach to patients reporting beta lactam allergy.