ANAPHYLAXIS AND FOOD HYPERSENSITIVITY

Anaphylaxis presentations to an emergency department in Hong Kong: incidence and predictors of biphasic reactions

We describe the epidemiology, clinical features and management of anaphylaxis in a population in Hong Kong, including the features associated with progression to biphasic reactions and the nature of these reactions. A retrospective review was undertaken of patients of all age groups, presenting consecutively to the resuscitation room of a large Hong Kong emergency department with the diagnosis of anaphylaxis, from March 1999 to February 2003. There were 282 patients included. Median age was 28 years, with 59% male. A precipitant was identified in 89%, with 19% of patients claiming a known allergy to the precipitant. Seafood was responsible for 71% of all food-related reactions. More patients reacted to nonsteroidal anti-inflammatory drugs rather than antibiotics. Cutaneous features were present in 79%, and 12% presented with hypotension. Ninety-five percent received H1 antagonist, and 67% received epinephrine. Biphasic reactions were reported in 15 (5.3%) cases with 20% of these patients having unstable vital signs. The mean time from treatment to onset of biphasic reaction was 8 h (range 1-23). Patients with respiratory features on initial presentation were less likely to develop biphasic reactions. It is concluded that prolonged observation of patients with anaphylaxis is important, because of the risk of biphasic reactions. Better education could prevent recurrent anaphylaxis.

Buckwheat pillow-induced asthma and allergic rhinitis

BACKGROUND

Immunoglobulin (Ig)E-mediated hypersensitivity is a mechanism suggested to explain adverse reactions to buckwheat. This is the first reported case in the United States of a person who developed asthma and worsening allergic rhinitis after exposure to a buckwheat pillow.

OBJECTIVE

To describe a patient who developed asthma and worsening allergic rhinitis after exposure to a buckwheat pillow and to provide evidence that the adverse reaction was IgE-mediated.

METHODS

The patient underwent skin prick and ImmunoCAP testing (Pharmacia Diagnostics, Kalamazoo, MI) to buckwheat as well as skin prick testing to several environmental allergens.

RESULTS

The patient showed a 4+ skin prick test response to buckwheat. He also showed 4+ positive skin prick responses to multiple trees, grasses, and weeds, Alternaria, Helminthosporium, dog, and histamine control and was 3+ positive to house-dust mites, Penicillium, Aspergillus, cat, and feather mix. His negative control was negative. His ImmunoCAP test for buckwheat-specific IgE was class 4, or strongly positive. He had normal spirometry values. Performance of house-dust mite avoidance measures did not result in improvement of the patient's symptoms. Removal of the patient's two buckwheat pillows resulted in resolution of his asthma and improvement of rhinitis symptoms.

CONCLUSIONS

The positive skin prick and ImmunoCAP test to buckwheat along with the positive clinical response to buckwheat pillow elimination support an IgE-mediated mechanism in explaining our patient's buckwheat pillow-induced asthma and allergic rhinitis.

Update on the clinical features of food-induced anaphylaxis

Food-induced anaphylaxis has become the leading cause of anaphylactic reactions that occur outside hospital. We introduce the present review with a definition of food-induced anaphylaxis, including its prevalence and proposed etiology. Second, we discuss an entity that is increasingly being recognized: exercise-induced food anaphylaxis, which may be triggered by specific foods or at times where no specific food has been identified. Third, we review current attempts to identify specific food antigens that are responsible for anaphylaxis to well-known triggers (i.e. peanut, as well as more unusual antigens). Fourth, we discuss current treatment options available (i.e. patient education, food avoidance, acute symptom recognition, and early use of self-administered epinephrine). Additionally, we discuss outcome data regarding the morbidity and mortality related to food allergy and anaphylaxis. Finally, information regarding experimental immunomodulatory therapy is presented.

Effect of allergist intervention on patient-centered and societal outcomes: allergists as leaders, innovators, and educators

Atopic disorders, which afflict millions of Americans and hundreds of millions worldwide, are at epidemic levels with concomitant increases in morbidity and mortality. Environmental and lifestyle changes over the past three to five decades are proposed causes for this pandemic and as such present major burdens to reverse. The scope of allergy practice bridges directly on this challenge. Allergy as a specialty is a major leader in developing effective strategies to confront this epidemic. Allergists have made major contributions to the understanding of the risk factors, immunology, pathophysiology, immunomodulation, and prevention of atopic and immunologic disorders. Allergist epidemiologists and clinicians have helped develop and implement national and international guidelines in the recognition, management, and prevention of asthma and rhinitis. Allergist clinical researchers are active in (1) outcomes research that demonstrates convincingly the value of allergy as a specialty in asthma, allergic rhinitis, anaphylaxis, drug and food allergy, and other atopic disorders, (2) National Institutes of Health clinical trials that will form the basis for the future treatment of asthma and allergic disease, and (3) pharmaceutical trials that evaluate new, effective, and safe medication to treat atopic disease. Allergist educators, comprising academic and practicing allergists, supported by allied health professionals, national associations, and affiliated lay organizations, provide comprehensive education to fellows, residents, colleague physicians, media, the public, and patients. Documentation of the value of allergists in improving patient-centered and societal outcomes in their core domain, allergy, is the appropriate final topic contribution in the important series "New millennium: The conquest of allergy."