target="_blank" rel="nofollow" href="#u179e53d2-31a2-515d-8b81-daeb30dd6b30">Aberer 1992).
Beginning with diagnosis, clinical allergologists experience practical difficulties and unresolved problems.
The discovery of immunoglobulin E in 1967 (by K. and T. Ishizaka at the same time as Johansson and Bennich) made it possible to prove allergenically relevant factors in the patient's blood. However, the initial great expectations that positive proof of specific IgE antibodies invariably signify a manifested allergy to a particular substance soon had to be scaled back considerably.
Leading experts of allergology agreed meanwhile that a correlation between positive proof of specific IgE antibodies and clinical symptoms may not always be sufficient to conclusively diagnose an allergy. In a broad study of 5000 randomly selected people who did not have any apparent allergies, more than one-third showed positive skin reactions to one or more of the common allergens.
”These people produce specific IgE without developing allergic symptoms” (Roitt 1987).
Fig. 2.1 Importance of anamnesis in allergy diagnosis (according to Ring).
It is generally known that skin and blood tests, particularly with regard to food allergies, are unreliable (Reimann 1989, Wahn 1987 etc.).
“We have to admit that we do not have good test methods when it comes to foods” states Aberer. He goes on to say that in the case of in vitro methods showing positive test results of numerous differing IgE antibodies in the same patient, which occurs quite often, “allopathic medicine is unable to determine which ones are relevant” (Aberer 1992).
Again and again anamnesis is emphasized. According to Ring, it amounts to a good 50% of the diagnosis (Fig. 2.1). Aberer estimates it to be as high as 80%.
We will show later on that, due to the masking effect, a patient often does not know that he or she is allergic to a particular substance. This occurs mainly with the most important food allergies, that is to say chronic forms where allergens are ingested daily. According to Ring, in vivo test methods designed to provoke an allergy or eliminate allergens are critical to confirming the existence of a food allergy. Various elimination diets as well as the search for allergens by adding suspected allergy-provoking foods may cause problems for the patient. Besides taking a long time, they are not reliable and cause additional stress on the patient's body.
The intragastric method of provocation using endoscopy (IPEC) exemplifies the difficult situation that arises when diagnosing foods allergies (Fig. 2.2). The suspected allergen is endoscopically introduced to the gastric mucous membrane whose reaction is then assessed macroscopically and microscopically. At the same time the antihistamine release can be measured in loco. Undoubtedly this heroic method was developed only because the conventional immunological diagnosis of food allergies is essentially ineffective.
Fig. 2.2 Intragastric method of provocation using an endoscope (IPEC according to Reimann).
We do not want to dispute the serious attempts of allergologists to solve the manifold problems concerning allergy diagnosis. However, viewed critically, a certain perplexity and helplessness must be acknowledged.
Serological in vitro methods as well as different tests on skin and mucous membrane are part of the daily allergological routine. Even though they form the indispensable basis of clinical allergology for numerous physicians, clinicians, and specialists, it does not mean that the results are relevant.
Erroneous negative as well as positive test results are more common than admitted.
A typical example is the allergy to chicken egg proteins, which is often overrated. According to a study by Hattewig and Kjellmann (1984), specific IgE antibodies to chicken egg protein can be found in almost one-third of all healthy children after they have started eating chicken eggs. Bear in mind that these are children who never had any allergic symptoms until the time of the examination. Minute quantities passed on through the mother's milk commonly appear as sensitivities to chicken egg protein in breast-fed babies. Serological test results are positive, but no symptoms can be observed (Gerrard 1979). In the case of babies and infants, initial contact with a substance seems to be sufficient to stimulate the creation of specific IgE antibodies. These are not necessarily a definitive sign of a clear allergy.
Obviously other factors play a role, besides the creation of antibodies, for allergy symptoms to occur. This conclusion led to the theory of allergy manifestation. It purports that an allergy does not create symptoms unless immune activity exceeds a certain point. When this threshold is reached depends on the encompassing circumstances such as allergen exposure, genetic predisposition, and the ability to create IgE antibodies (IgE low responder, IgE high responder). Various circumstances may play a role such as temporary IgA deficiency, lower suppressor T-cell activity, and viral infections. The latter may expedite the release of histamines from basophils. By no means evident, the postulated factor obviously essential to manifest allergies was called factor x to express a hypothetical mechanism (Fig. 2.3).
The therapy itself is also confronted with considerable unsolved problems despite worldwide research and significant financial investment.
In the words of the German immunologist W. Müller, allergy treatment aims to “develop immunological tolerance (to the allergen) over the course of many years.” He continues with resignation: “To date we have no therapeutic modality that has achieved this even though individual cases show an eradication of symptoms after avoidance of and subsequent renewed exposure to the allergen” (Müller 1987).
Meanwhile we have experienced that the avoidance of allergens has been successful in only a few cases. The significance of “avoidance even to the point of complete isolation from the allergen” was unknown and consequently had not been taken into consideration.
In contrast to avoidance, clinical allergology uses hyposensitization to treat allergies. The patient frequently receives small amounts of the allergen. The goal is twofold: to prevent the appearance of allergy symptoms and/or for the patient to be able to tolerate a higher dose when he or she comes into contact with the natural allergen. True healing through hyposensitization treatment has yet to be documented. The effectiveness of this therapy has been the subject of discussions since the first controlled study by Frankland and August in 1954 (Uhlmann).
Fig. 2.3 The theory of allergy manifestation (according to Roitt et al. 1987).
The decrease in IgE antibodies concurrent with an increase in immunoglobulins of type IgG (Djurup and Osterballe 1984), often apparent with this therapy, bear little correlation to the clinical symptoms. Its significance has yet to be explained.
The efficacy of hyposensitization immunotherapy has been unequivocally proven solely in the case of bee and wasp allergies. This is very risky for the patient and currently is generally only recommended as in-patient treatment in specialized departments with specialized equipment, staff, and experience.
Decreasing patients' sensitivity has been somewhat successful with pollinosis. Generally, however, therapy extends over a very long period. There is always the
