Symptoms, anaphylaxis

Examples of disease states Erythema urticaria angioedema respiratory symptoms GI symptoms anaphylaxis Drug-induced hemolytic anemia, thrombocytopenia, agranulocytosis (immune form) Serum sickness Drug-induced vasculitis Allergic contact dermatitis Psoriasis Maculopapular exanthema AGEP FDE DRESS SJS TEN EM... 

Table 2. Prevalence of symptoms in anaphylactic reactions according to Przybilla and Rueff [see 18]. A meta-analysis of 1,865 cases from 14 publications (Liebermann) and 865 own patients with insect venom anaphylaxis... 

Anaphylaxis most commonly starts with symptoms on the skin or the respiratory tract (table 2). The symptomatology is variable there is no obligatory involvement of all organ systems. A major characteristic of anaphylaxis is the rather rapid onset of symptoms after contact with the elicitor. The interval varies between a few seconds or minutes until 1 or 2 h, partly dependent upon the route of application (rapid onset after intravenous allergen exposure) and degree of sensitization. Experience in insect sting anaphylaxis in... 

According to the different intensity of clinical symptoms, several attempts have been made to classify anaphylaxis according to severity, the most common scales have been published by Mueller [26] and Ring and Messmer [35] (table 3). 

Helbling A, Hurni T, Mueller UR. Pichler WJ Incidence of anaphylaxis with circulatory symptoms a study over a 3-year period comprising 940,000 inhabitants of the Swiss Canton Bern. Clin Exp Allergy 2004 34 285-290. 

The route of antigen administration can alter the speed of antigen access to the circulation and, thus, the systemic symptoms in anaphylaxis models. For example, allergen ingestion typically induces anaphylaxis that includes gastrointestinal symptoms, such as diarrhea [4]. These intestinal anaphylaxis models in mice are dependent on IgE-induced mast cell activation, and the release of PAF and serotonin (rather than histamine) [1,4]. 

The most frequent symptoms of anaphylaxis in patients with mastocytosis are decreased blood pressure and tachycardia. Also observed are dizziness, dyspnea, flushing, nausea and diarrhea [4]. Severe reactions are typical for patients with mastocytosis. In 55 patients with insect sting allergy and confirmed mastocytosis, 81% of patients experienced severe anaphylaxis with shock or cardiopulmonary arrest, whereas clinical reactions of this severity occurred in only 17% of 504 patients without evidence for mastocytosis and normal tryptase levels [29]. In another study in... 

Diet should be modified only in cases where foods have been proven to elicit symptoms. Patients with mastocytosis and Hymenoptera venom exposure are at risk for severe anaphylaxis. Thus, specific immunotherapy should be considered in patients with Hymenoptera venom allergy and then administered under close supervision [31]. The majority of patients with mastocytosis reportedly tolerate immunotherapy without significant side effects and appear protected following this approach [33,40]. However, there does appear to be some increased risk for adverse reactions during initiation of immunotherapy, as well as for therapy failures [31, 33]. An increased maintenance dose of insect venom has been reported to carry better success rates by sting provocation [41]. Also, in the light of 2 fatal cases of anaphylaxis after discontinuation of SIT in patients with mastocytosis [30], lifelong immunotherapy should be considered [26]. 

The application and development of new in vitro diagnostic techniques aims to enable physicians to reach an allergy diagnosis with no risk for the patient. This is particularly desirable in the case of serious reactions such as anaphylaxis, by confirming the existence of an anaphylactic reaction and differentiating between individuals which present with sensitization but no cUnical symptoms following exposure to the allergen from those that show a serious clinical reaction. 

Allergy mediated by selective IgE to certain types of NSAIDs by which symptoms are caused exclusively by a specific group of NSAIDs and no cross-reactivity exists with the other groups of anti-inflammatories. In a study carried out with 26 methimazole-allergic patients with IgE-mediated reactions [33], 14 of which developed anaphylaxis, BAT showed a sensitivity of 42% with an optimum specificity of 100%. No other validated in vitro test exists to date for the diagnosis of this disorder and so it represents an essential aid to diagnosis. 

Reisman RE Natural history of insect sting allergy relationship of severity of symptoms of initial sting anaphylaxis to re-sting reactions. J Allergy Clin InununoJ 1992 90 335-339. 

Not all symptoms after RCM exposure do resemble a hypersensitivity reaction. Toxic reactions related to the toxicity of RCM, imspecific reactions of unknown origin and or factors unrelated to RCM, such as chronic idiopathic urticaria, may occur (fig. 1) [3]. Hypersensitivity reactions to RCM may both present either under the clinical picture of anaphylaxis with the potential to result in fataUties or as delayed occurring... 

As immediately after the reaction, elevated plasma histamine and serum or plasma tryptase levels of histamine and tryptase have been found [31, 34], an anaphylaxis may be confirmed by blood samples for histamine analysis drawn as soon as possible after the reaction and for tryptase drawn 1-2 h after onset of symptoms [31]. Tryptase values have to be compared to baseline levels. 

They differ to some extent from signs and symptoms that occur during anaphylaxis not associated with anesthesia. Early subjective symptoms such as malaise, pruritus, sensation of heat, and dizziness are absent in the anesthetized patient. Cutaneous signs in a completely wrapped patient may escape the attention of the anesthetist. The increase in heart rate, a decrease in blood pressure and an increase in airway resistance may be initially misinterpreted as a result of a pharmacological dose-related effect of the drugs, or of excessively light anesthesia. Many differential diagnoses have to be considered (table 1). 

Initial features are mostly pulselessness, difficulty in ventilation, desaturation, and a decreased end-tidal CO2. Cutaneous symptoms are observed in 66-70% of patients in case of IgE-mediated reactions but in more than 90% in non-IgE-mediated reactions. On the contrary, cardiovascular collapse and bronchospasm are more frequent in IgE-dependent reactions (table 2). Severe anaphylaxis may be a primary cardiac arrest [9]. 

The well-known adverse reaction formerly often observed after intramuscular injection of clemizol penicilUn in the treatment of syphilis with anaphylaxis-like symptoms plus CNS involvement in the absence of immimological sensitization to penicillin was called the Hoigne syndrome or embolic-toxic reaction, and might be explained by intravasal appUcation of LA with subsequent toxic effects [8]. 

Given the unexpected occurrence of anaphylaxis, the rapidity with which symptoms evolve after exposure to the trigger, and the observation that delay in epinephrine injection is associated with fatality [15, 16], randomized controlled trials of epinephrine in anaphylaxis will not be easy to conduct however, it is time to consider the possibility of performing such trials. Future directions with regard to studies of the optimal dose and optimal route of administration of epinephrine in anaphylaxis that do not involve a placebo control will be outlined at the end of this review [17]. 

Up to 20% of anaphylaxis episodes in adults, and up to 6% of episodes in children, are biphasic or protracted, and involve recurrent or persistent symptoms without any ongoing or additional exposure to the anaphylaxis trigger. Administering too little epinephrine too late during treatment of the initial symptoms of an anaphylaxis episode is one of the factors reported to increase the risk of biphasic or protracted anaphylaxis [27]. 

Epinephrine autoinjectors should be prescribed in the context of a written Anaphylaxis Emergency Action Plan that is developed with the input of the person at risk for anaphylaxis, or the caregiver(s) of the child at risk [45]. The Plan should remind the person at risk about the common symptoms and signs of anaphylaxis, stress the importance of prompt epinephrine injection, and clearly state that Hj-antihistamines... 

Past history of anaphylaxis Incidence of symptom by extremely small amount... 

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