The practice of allergology

The practice of allergy involves the diagnosis and care of patients with:

• Rhino-conjunctivitis, along with nonallergic rhinopathy

• Sinusitis, both acute and chronic, alone or complicated with nasal polyps 

• Otitis and Eustachian tube disorders 

• Asthma and all its forms including cough-variant asthma and exercise-induced asthma 

• Cough from all causes 

• Bronchitis, chronic obstructive pulmonary disease (COPD) and emphysema 

• Hypersensitivity pneumonitis 

• Alveolitis 

• Atopic dermatitis/eczema 

• Contact dermatitis 

• Urticaria and angioedema 

• Drug allergy 

• Food allergy 

• Latex allergy 

• Insect allergy and stinging-insect hypersensitivity 

• Gastrointestinal reactions resulting from allergy, including eosinophilic esophagitis and gastroenteritis 

• Anaphylactic shock

• Immunodeficencies, both congenital and acquired 

• Occupational allergic diseases 

• Identifying and managing risk factors for progression of allergic diseases — the «allergic march» 

• Other specific organ reactions resulting from allergy

• Conditions that may mimic or overlap with allergic disease 

• An expert knowledge of the epidemiology and genetics of allergic diseases Immunodeficencies and autoimmune diseases, with special knowledge of regional and local allergens

As part of the practice of allergy, the allergist should be capable of ordering and interpreting allergy-and immunology-related laboratory tests:

• Evaluating total IgE and allergen specific IgE measurements

• Carrying out appropriate provocation testing for allergic and immunologic disease 

• Providing analysis and advice regarding local environmental/airborne allergens and irritants, as well as the analysis and advice regarding ingested allergens/ irritants

• Conducting and/or evaluating tests of pulmonary function and tests of inflammatory markers

• Conducting and/or evaluating tests of nasal function; this may include examination of nose and throat via fiberoptic rhinoscopy and nasal endoscopy 

• Specific allergen and venom immunotherapy 

• Providing pharmacotherapy of allergic disorders and related diseases including aero-allergens, drugs, venoms, occupational allergens, and food allergens 

Because of the highly specialized training, the allergist can advise both patients and other members of the medical community on:

 The role of effector cells involved in allergic disease (stem cells, • lymphocytes, mast cells, basophils, eosinophils, neutrophils, • monocytes, macrophages, dendritic cells) 

• The molecules involved in the immunological response (both innate and acquired) including chemical mediators; immunoglobulins; antibodies; complement; cytokines;interleukins; chemokines and their receptors; human leukocyte antigen/major histocompatibility complex (HLA/MHC) antigens • The main hypersensitivity reactions 

• Cell-to-cell interactions 

• The scientific in vitro laboratory diagnostic tests for allergy and 

• their selection and interpretation, including allergenspecific in vitro assays; enzyme-linked immunosorbent assays (ELISAs); Western blotting; tests for inflammatory markers, protein and cellular antigen stimulation tests; histamine release assays

The allergist is especially competent in performing/interpreting the following: 

• Allergic history and physical examination 

• Skin testing 

• Where necessary, investigating alternative diagnoses 

• Environmental modification strategies to reduce allergen exposure 

• Specific immunotherapy (allergen vaccines; both oral and injective)

• Immunomodulatory therapy 

• Drug desensitization 

• Evaluation and treatment of allergic and immunologic competence 

• Management and treatment of anaphylactic shock 

• Education for patients, caregivers and primary care physicians 

Undergraduate And Postgraduate Education For Primary Care Physicians And Pediatricians

Identified Need: 

There is a need for undergraduate and postgraduate training in allergy, asthma and clinical immunology for general practitioners and pediatricians such that primary care physicians and pediatricians may appropriately assist patients with allergic diseases. 

Recommendation: Allergic diseases are a major cause of morbidity and mortality. Suitable undergraduate and postgraduate training for medical students, physicians, pediatricians and other healthcare professionals will prepare them to recognize allergy as the underlying cause of many common diseases. It will also enable them to manage mild, uncomplicated allergic disorders by targeting the underlying inflammatory mechanisms associated with these diseases. They will learn when and how to refer the more complicated cases for a specialist consultation. Such education at the general practice level is of paramount importance since the vast majority of patients with allergic diseases are cared for by primary care physicians and pediatricians. These clinicians will also be required to comanage such patients with an allergy specialist and should be aware of the role of the allergist/clinical immunologist in investigating, managing and caring for patients with complex allergic problems.

Recognition Of The Specialty And Training Programs

Identified Need: Globally, medical education providers need to recognize allergy / clinical immunology as a specialty or sub-specialty, resulting in adequate training programs for optimal patient care. 

Recommendation: Expertise in allergy and clinical immunology should be an integral part of the care provided by all specialty clinics. Where allergy/clinical immunology training is not presently available or recognized as a specialty, training and national accreditation programs should be instituted to enable selected physicians to receive formal training and the qualifications required to become certified allergists/clinical immunologists. Such programs will also enable general practitioners, including pediatricians, to enhance their capacity to provide for the routine care for patients with allergic diseases.

Public Awareness Of Allergy, Asthma And Clinical Immunology

Identified Need: In most populations around the world, there is a lack of adequate education about, and awareness of, the morbidity and mortality associated with allergic diseases; the often chronic nature of these diseases; the importance of consulting a physician trained in allergy, asthma and clinical immunology; and the medications and treatments available to appropriately treat and prevent these diseases. 

Recommendation: Public health authorities should target allergic diseases as a major cause of morbidity and potential mortality. They should collaborate with national allergy, asthma and clinical immunology societies and patient support groups to publicize the necessity for general awareness and appropriate care for these diseases. 

The practice of allergology

Allergy is a very common ailment, affecting more than 20% of the populations of most developed countries. The major allergic diseases, allergic rhinitis, asthma, food allergies and urticaria, are chronic, cause major disability, and are costly both to the individual and to their society. Despite the obvious importance of allergic diseases, in general allergy is poorly taught in medical schools and during post-graduate medical education, and many countries do not even recognize the specialties of Allergy or Allergy and Clinical Immunology. As a consequence, many or most allergic patients receive less than optimal care from non-allergists. The World Allergy Organization has recognized these needs and developed worldwide guidelines defining What is an Allergist?1 , Requirements for Physician Competencies in Allergy: Key Clinical Competencies Appropriate for the Care of Patients with Allergic or Immunologic Diseases2 , and Recommendations for Competency in Allergy Training for Undergraduates Qualifying as Medical Practitioners3 . These important position papers have been published worldwide over the past few years, but it is far too soon to see whether they will influence the need for more, better and improved training in allergy worldwide.

An allergist is a physician who, after training in internal medicine or pediatrics, has successfully completed a specialized training period in allergy and immunology. As part of allergy training, all allergists are trained in the relevant aspects of dermatology, pneumonology, otorhinolaryngology, rheumatology and/or pediatrics. Subject to national training requirements, allergists may be also partially or fully trained as clinical immunologists, because of the immune basis of the diseases that they diagnose and treat. In most countries where the allergy, or allergy and clinical immunology, is acknowledged as a full specialty, the duration of the training is four/five years (including the common trunk in internal medicine and/or other disciplines, and two/three years of allergy and clinical immunology); where it is a subspecialty the approved period of training in allergy and clinical immunology will be two/three years after completion of the main specialty. Depending on national accreditation systems, completion of this training will be recognized by a Certificate of Specialized Training in Allergy, in Allergy and Immunology, or in Allergy and Clinical Immunology, awarded bya governing board. In some countries this will follow successful completion of a certification test or a final exam and in other countries by competencies being signed-off by a training supervisor. In some countries the allergist treats both adults and children while in some others, pediatricians, with specialty or sub-specialty in allergy, are competent to treat children

Epidemiological Studies Of Allergic Diseases

Identified Need: 

In several parts of the world, there is a paucity of published epidemiological information about the overall prevalence of allergic diseases and, in particular, about specific diseases. For example, there is little or no information about severe asthma; anaphylaxis; food allergy; insect allergy; drug allergy; and complex cases of multi-organ allergic disease. Data concerning some of these disorders are available in a few countries, but only for certain age groups. 

Recommendation: 

Every country should undertake epidemiological studies to establish the true burden of allergic diseases; asthma; and primary and secondary immunodeficiency diseases. This is the first essential step in ensuring the provision of adequate physician and healthcare professional services to meet both current and future needs.

Allergens And Environmental Pollutants

Identified Need: 

Evidence-based information about the major indoor and outdoor allergens and pollutants responsible for causing or exacerbating allergic diseases and asthma is either lacking or, when available, is not always universally accessible.

Recommendation: 

Local indoor and outdoor allergens and pollutants which cause and exacerbate allergic diseases should be identified and, where possible, mapped and quantified. Appropriate environmental and occupational preventative measures should be implemented where none exist or as necessary. Strategies proven to be effective in disease prevention should also be implemented. 

Availability Of Allergy, Asthma And Clinical Immunology Services (Allergists) And Appropriate Medications

Identified Need: There is an increasing need for more allergy specialists and for the existence of local and regional allergy diagnostic and treatment centers in order to facilitate timely referrals for patients with complex allergic diseases. Accessibility to affordable and costeffective therapy and to novel therapies is needed. For example, adrenaline auto-injectors for patients at risk of anaphylaxis; new and more effective medications to treat severe asthma; and access to allergen immunotherapy are lacking in some parts of the world. 

Recommendation: Public health officials should provide for adequate allergy/ clinical immunology services, including access to specialists and diagnostic and treatment centers. Allergists should be able to prescribe the most cost-effective medication to manage a patient’s disease. Examples include adrenaline auto-injectors to treat anaphylaxis; anti-IgE for severe asthma; a variety of very effective medications to treat chronic urticaria and angioedema, hereditary angioedema, rhinitis, conjunctivitis and asthma. 

Allergen-specific immunotherapy is effective in preventing the onset of asthma and is the only available treatment to prevent anaphylaxis and death from bee, wasp, yellow jacket, hornet and ant induced anaphylaxis. Consultations with allergists, timely diagnosis and treatment are necessary to improve longterm patient outcomes and quality of life and to reduce the unnecessary direct and indirect costs to the patient, payer and society.

HEALTH ECONOMICS, MEDICAL EDUCATION AND COST-EFFECTIVE HEALTH CARE IN ALLERGY

Health Care Delivery and Health Economics in Allergy 

• Asthma and allergic diseases are significant causes of morbidity on a global scale. 

• Asthma disproportionately affects minorities and people from lower socio-economic groups. 

• The total global cost of care for people with asthma and allergic disorders is disproportionately high despite the relatively low cost per person mainly due to the high prevalence of these disorders. 

• The most effective management for these disorders is to teach patients self-management skills. 

• Education should focus on training physicians to promote and foster self-management skills in their patients

Medical Education in Allergy

The intended outcomes for clinician and healthcare professionals training in allergy are to: 

• Produce graduates equipped to further their careers in healthcare and in particular to enhance the number of individuals trained in the mechanisms and management of allergic diseases. 

• Develop an understanding of the processes involved in improving the management of patients with allergic disease. 

• Develop new areas of teaching in response to the advance of scholarship and the needs of vocational training. 

• Provide a training in research skills. 

• Develop skills and understanding of the more complex components of allergic disease encountered in specific areas of practice.

The Cost-Effectiveness of Consulting an Allergist

• Allergic diseases are chronic conditions with systemic involvement that can affect multiple organs and systems throughout the lifespan of atopic (allergic) subjects. 

• In assessing the economic burden of allergic diseases, the costs of several organ-specific diseases need to be aggregated, including the nose (allergic rhinitis), sinuses (rhinosinusitis); lungs (asthma); skin (atopic eczema); and others. 

• Cost-effective analyses (CEA) assess the comparative effects of one health care intervention over another, under the premise that there is a need to maximize the effectiveness relative to its cost. 

• A cost-effective intervention could, if incorrectly used, generate unnecessary costs, provide no benefit and even cause harm.

• The allergist is an expert in tailoring therapy to the individual patient and adjusting treatment dosages in more severe or complex cases. The main defining characteristics of allergists are their appreciation of the importance of external triggers in causing diverse diseases; their expertise in both the diagnosis and treatments of multiple system disorders, including the use of allergen avoidance and the selection of appropriate drug and/or immunological therapies; and their knowledge of allergen specific immunotherapy practices. 

• Misinterpretation of the results of diagnostic tests by nonspecialists can lead to over-diagnosis and inappropriate management which can be harmful for the patient. It may lead to over-prescription of therapy and costly and unnecessary allergen avoidance measures, including exclusion diets that can lead to nutritional deficiency and secondary morbidity. Conversely, the under-appreciation of the severity of asthma can lead to life-endangering under-treatment or the lack of potentially life-altering immunotherapy.

 • The cost-effectiveness of allergist consultation will be demonstrated by improved patient outcomes and experiences together with a reduction in unnecessary expenditure by payer, society or patient/family.

Allergy Education for Patients and Families

• The provision of appropriate training and education for patients and families is fundamental to the management of allergic disease.

• The evidence base for the efficacy of education and training is relatively weak but it is effective in asthma and, to a lesser extent, eczema and anaphylaxis. 

• Different age and ethnicity populations require different educational approaches. 

• Modern information technology is valuable, especially to educate younger subjects. 

• Education and training programs should contain a written self management action plan

Allergen Avoidance

• Effective allergen avoidance leads to an improvement of symptoms in allergic patients. 

• Several studies of comprehensive environmental interventions in asthmatic children report benefits. 

• There is little evidence to support the use of a simple single intervention, e.g., only covering bedding, to control dust mite allergen levels. 

• Similarly, in mite allergic patients with rhinitis, single mite avoidance measures are not beneficial. 

• The following is a guide for a pragmatic approach to allergen avoidance:

– Use a comprehensive environmental intervention to achieve the greatest possible reduction in allergen exposure; 

– Tailor the intervention to the patient’s allergen sensitization and exposure status;

 – If unable to assess the level of allergen exposure, use the level of allergen-specific IgE antibodies or the size of skin test wheal as an indicator;

 – Start the intervention as early as possible in the natural course of the disease;

 – Primary prevention strategies aimed at eliminating or reducing exposure to potentially sensitizing agents should be developed and evaluated. 

PREVENTION OF ALLERGIC DISEASES

• The rise in prevalence of allergic diseases has continued in the industrialized world for more than 50 years. 

• Sensitization rates to one or more common allergens among school children are currently approaching 40%-50%. 

• Strategies used to tackle these problems are thus far ineffective. 

• Primary prevention is difficult because the reasons for increased sensitization rates are unknown. Also, the mechanisms involved in the progression of sensitization in increasing numbers of individuals resulting in allergic diseases are incompletely understood. Asthma and allergies may have their origin early in life, even in-utero.

• Reliable early markers of IgE-mediated diseases are unavailable. 

• Novel research indicates that tolerance is the key to prevention. More research about the mechanisms involved in the development of tolerance should be encouraged. Inadequate or lack of tolerance in allergic individuals appears to link with immune regulatory network deficiencies. 

• National asthma and allergy plans (e.g. The Finnish Asthma Programme 1994-2004) have concluded that the burden of these community health problems can be reduced. The change for the better is achieved as governments, communities, physicians and other health care professionals, and patient organizations commit to an educational plan to implement best practices for prevention and treatment of allergic diseases. 

Pharmacotherapy of Allergic Diseases

• Subjects from all countries, ethnic and socio-economic groups, and ages suffer from allergies.

• Asthma and allergic rhinitis are common health problems that cause major illnesses and disability worldwide.

• The strategy to treat allergic diseases is based on: (i) patient education, (ii) environmental control and allergen avoidance, (iii) pharmacotherapy, and (iv) immunotherapy. 

• Pharmacotherapy is the mainstay of treatment for allergic diseases because it not only controls symptoms but improves the quality of life.

• Primary care physicians play an important role in first line management of allergies. They have to make the initial clinical diagnosis, begin treatment, and monitor the patient. 

• Allergy specialists are trained to make a specific diagnosis and treat patients with allergies, particularly those with moderate/severe disease.

• The chronic nature of allergies makes it essential to propose and explain long-term management strategies to patients, health care policy makers, and government authorities. 

• In recent decades, a substantial improvement has been made in the efficacy and safety of allergy pharmacotherapy. 

• Disease management using evidenced-based practice guidelines has been shown to yield better patient outcomes.

Allergen Specific Immunotherapy

• Allergen specific immunotherapy is recognized as an effective treatment for respiratory allergy and Hymenoptera venom allergy. 

• Subcutaneous Immunotherapy (SCIT) represents the standard modality of treatment. Sublingual Immunotherapy (SLIT) which is now accepted as an alternative to injection immunotherapy, has recently been introduced into clinical practice. 

• The additional effects of allergen specific immunotherapy, that are lacking with pharmacological treatment, are the long-lasting clinical effects and the alteration of the natural course of the disease. This prevents the new onset of asthma in patients with allergic rhinitis and prevents the onset of new sensitizations. 

• The mechanisms of action of specific immunotherapy are multiple and complex, and result in a modification of the immunological responses to allergens, with subsequent reduction of the allergic inflammatory reaction. The mechanisms of action of SCIT and SLIT are similar.

• SCIT maintains its beneficial effects for years after it has been discontinued. This long-term or carry over effect also occurs with SLIT. 

• SCIT indications, contraindications, limits and practical aspects are defined in numerous guidelines. 

• SLIT is considered a viable alternative to SCIT and is used in clinical practice in many countries. A 2009 World Allergy Organization Position Paper further details the indications, contraindications, and methodology of using SLIT.

• New forms of immunotherapy, allergen products, and approaches to food allergy and atopic eczema are under investigation.

Biological Agents 

• Research in allergy and immunology has led to a variety of novel therapeutic approaches; some agents are already utilized in clinical practice and more are in clinical trials. 

• New therapeutic approaches include toll-like receptor agonists, cytokine blockers, specific cytokine receptor antagonists and transcription factor modulators targeting syk kinase, peroxisome proliferator-activated receptor gamma, and nuclear factor kappa B. 

• The anti-IgE mAb omalizumab is effective to treat allergic asthma, but the criteria to select patients for this type of therapy are not well-defined.

Socio-economic Factors and Environmental Justice

• The global prevalence, morbidity, mortality and economic burden of asthma have increased over the last 40 years.

• However, the growth and burden of the disease is not uniform. Disparities in asthma morbidity and mortality, with an inverse relationship to social and economic status, are increasingly documented around the world. 

• Asthma and other atopic disorders may be more concentrated among those of lower socio-economic status because they also bear a disproportionate burden of exposure to suboptimal, unhealthy environmental conditions (e.g. physical, social, and psychological conditions).

• Future research needs to pay increased attention to the social, political, and economic forces that result in marginalization of certain populations in disadvantaged areas of the world which may increase exposure to known environmental risk factors contributing to the rising asthma burden.

Climate Change, Migration and Allergy 

• The Earth’s temperature is increasing as illustrated by rising sea levels, glaciers melting, warming of the oceans and diminished snow cover in the northern hemisphere. 

• Climate change coupled with air pollutant exposures may have potentially serious adverse consequences especially for human health in urban and polluted regions. 

• High summer temperatures have an impact on rates of acute exacerbation and hospital admission for elderly patients with breathing problems and may cause unexpected death. 

• Pollen allergy is frequently used to study the interrelationship between air pollution and respiratory allergy. Climatic factors (temperature, wind speed, humidity, thunderstorms, etc.) can affect both biological and chemical components of this interaction.

• Changes in the weather such as thunderstorms during pollen seasons may induce hydration of pollen grains and their fragmentation which generates atmospheric biological aerosols carrying allergens. As a consequence asthma outbreaks can be observed in pollinosis patients. 

• Migration from one country to another involves exposure to a new set of pollutants and allergens as well as changes in housing conditions, diet and accessibility to medical services which may affect migrants’ health.

• Atopy and asthma are more prevalent in developed and industrialized countries compared with undeveloped and less affluent countries. 

• Migration studies provide information on the role of environmental factors on the development of atopy and asthma. 

• Physicians should be aware that environmental and climate changes may enhance the development of allergic diseases and asthma.

 • Physicians should be aware that migrants, especially from developing to more developed countries, are at increased risk to acquire allergic diseases and asthma and that the effect is age and time-dependent. Early age and longer time increase the likelihood of developing atopy and asthma.

EVIDENCE BASED APPROACHES TO DIAGNOSIS AND MANAGEMENT

Diagnosis and Identification of Causative Allergens

• Confirmation of allergy and identification of causative allergens are crucial to correctly manage allergic diseases. 

• Precise diagnosis allows the implementation of therapies oriented to the etiologic factors of allergic diseases, such as environmental measures and immunotherapy. 

• Diagnosis begins with a detailed medical history and physical examination. 

• The identification of a temporal association between symptoms and allergen exposure constitutes the basis for further testing.

• Clinical suspicion is confirmed by means of investigation of IgE antibodies in vivo (skin tests) or in vitro. 

• Skin tests should include relevant allergens and the use of standardized allergen extracts.

• In vitro testing is especially useful when skin test results do not correlate with the history or cannot be performed.

• In vitro tests can be applied to “probability of disease” prediction in food allergy.

• There is a need for increased accessibility to allergy diagnosis and therapies and improved diagnostic methodologies that can substitute in vivo provocation tests for drug and food allergy. 

• The use of unproven tests increases the unnecessary costs of allergy diagnosis