Anaphylactoid reaction: symptoms, diagnosis and classification

The emergence of an allergic (anaphylactic) reaction is caused by exogenous agents, and its course is characterized by immediate type hypersensitivity. As a rule, it is possible to characterize the response of the organism by the life-threatening pathological condition of the skin, respiratory and cardiovascular functions. After the first contact with the antigen, the development of antibodies IgE, specific for its intended purpose, begins. They merge with cells responsible for the immunological processes in the body, and sensitization to the antigen occurs.

How are allergic reactions manifested?

The next ingress of the allergen promotes the release of bioactive substances responsible for immune forces, in particular histamine. At the moment of transition from abnormal chemical processes to unnatural physiology, changes are primarily reflected in blood vessels, lymph nodes, smooth bronchial muscles, which contributes to the development and early manifestation of the following syndromes:

• Decreased vascular tone;
• Sudden contraction of smooth muscle tissue of the intestine, bronchi, uterus;
• Violations of blood circulation;
• Inflammation and swelling of blood vessels.

Unlike allergic, anaphylactoid reaction, which physicians often call pseudoallergic, IgE antibodies are not mediated with basophils. Despite the similarity of the manifestation of the response processes, both manifestations are a generalized response of the hypersensitivity of the organism.

Medicinal allergens that cause anaphylactoid reaction

The anaphylactoid reaction is also a release of histamine, often already at the first contact with the stimulus. Pseudoallergens at the moment are a fairly wide range. Paradoxically, this reaction of the body often happens during the reception of drugs that stop allergies.

Anaphylactic and anaphylactoid reactions of the immediate type occur quite often after the administration of muscle relaxants, antibiotics, anesthetic drugs, opioids, local anesthetics, vaccination, hormone therapy, atropine and B vitamins. Allergens are also referred to as sera, antigens used for medical diagnostic purposes For the detection of cutaneous, venereal diseases. Cases of allergy to latex products have become more frequent. Anaphylactoid reaction to lidocaine is considered to be a widespread phenomenon, as the drug is used frequently in local anesthesia, but its complex chemical composition can cause side effects even in a healthy organism for which the allergy to the components of the medication is not characteristic.

Non-medicamentous stimuli

If we consider the cases of response reactions of the body to stimuli of a non-medicamentous nature, then basically food can be "problematic":

• Strawberries;
• crustaceans;
• honey;
• Nuts;
• Mushrooms;
• Fish of some varieties;
• Eggs;
• citrus.

Anaphylactoid reaction can occur when an insect or an invertebrate poisonous fauna agent bites. Patients who are constantly experiencing allergic manifestations of a non-drug character have huge risks of developing anaphylaxis in the case of surgical intervention under general anesthesia.

Classification of anaphylaxis

Hence the classification of allergic reactions. The first unit includes a variety of anaphylactic reactions that are divided into IgE mediated IgG mediated and mediated IgE and physical activity. Anaphylactoid pseudoallergic reactions are mediated by simple excretion of mediators, followed by drug-provoked actions, food and physical factors. A separate category is anaphylactoid reactions in mastocytosis; Mediated by immune complexes, immunoglobulin aggregates with the introduction of immune sera and mediated by cytotoxic antibodies, radiopaque substances.

How does anaphylaxis?

Morphine and many barbiturates, muscle relaxants, pethidine can affect mast cells, causing a release of histamine. At the same time, the clinical picture depends on the dosage and the rate at which the active substances enter the body. Practice shows that primarily the reaction is benign, limited only to manifestations on the skin.

Anaphylactoid reaction (ICD 10 assigned to this pathological syndrome) is characterized by unpredictability of further development and, possibly, complete absence of information on previous allergic responses of the body to antigens. Since the consequences of anaphylaxis to the crane are dangerous to health and life, it is important to detect the course of the complications in a timely manner and take appropriate measures. Regardless of the mechanism of an anaphylactic or pseudoallergic stimulus, the symptomatology can vary significantly. Bearing a purely individual character, manifestations can range from a slight jump in blood pressure and skin rashes to severe bronchospasm and a collapse in the functioning of the cardiovascular system.

At this stage, it is easy to note another difference in the action of pseudoallergenes on the body. Meanwhile, anaphylactoid reaction, the symptoms of which can be detected individually or perform in various combinations, is no less dangerous.

Symptomatic of anaphylactoid reaction

Symptoms of an allergic reaction in a patient in a waking state are:

• dizziness;
• General weakness of the body;
• Violation of heart rhythms (tachycardia, arrhythmia);
• Lowering of blood pressure;
• Difficulty breathing, attacks of suffocation, broncho- and laryngospasm, edema of the lungs and larynx;
• Burning of the skin, itching rashes, hives, hyperemia of the veins, edema Quincke ;
• Intestinal cramps, nausea, diarrhea, vomiting;
• Absence of pulse;
• Cardiovascular collapse;
• Slowing and stopping the work of the heart.

Possible complications after anaphylactoid reaction

The greatest threat is a shock, combined with bronchospasm. After a certain period of time (from 30 seconds to half an hour, sometimes 2-3 hours) the antigen that enters the body contributes to the development of pathological allergic processes in the body. In many ways the course of the reaction depends on the form of penetration of the stimulus (orally or parenterally). Rapid development often causes death, causing sudden acute respiratory failure, a critical drop in perfusion pressure, which leads to severe circulatory failure, cerebral edema or hemorrhage, impaired stem function, arterial thrombosis.

On the second day after the shock, the threat to life and recovery lies in the progression of concomitant diseases caused by an allergic reaction. Even after a couple of weeks, the risk of complications remains large. Often, after anaphylactic shock, doctors diagnose such dysfunctions and diseases:

• pneumonia;
• Vasculitis;
• Renal and hepatic insufficiency, hepatitis, glomerulonephritis;
• Epidermal necrolysis;
• myocarditis;
• Arthritis.

Similar consequences may threaten both anaphylactic and anaphylactoid reactions. The difference from anaphylactic shock of these pathologies lies in the fact that the latter requires preliminary sensitization and is not able to develop at the first encounter with an allergenic substance.

Treatment of anaphylaxis

It is correct to draw up an emergency treatment plan according to the diagnosis, only anamnesis will help, so it is extremely important to collect it. The symptomatology of allergy, that is, the clinical picture, also plays a significant role in making an early decision. However, the most reliable and full-fledged answer to the question of diagnosis can be obtained only after allergists and immunologists have conducted a laboratory study. In this case, based on the critical condition of the patient, first of all he must be provided with urgent medical assistance, and in case of cardiac arrest or respiration - resuscitating actions.

At the stage of recognizing the root causes of the allergic response of the body, the task of physicians is to carry out detailed differential diagnosis. This type of examination is designed to exclude the possible factors of influence, not associated with the release of histamine.

A similar reaction of the body to other non-allergic causes

Most often anaphylactic and anaphylactoid reaction (what is it and what are dangerous pathologies, it is important to know people who are prone to even the most harmless, at first glance, allergic manifestations in the form of rhinitis) have similarity with other factors potentially capable of causing bronchospasm, hypotension:

• Overdose with anesthetics;
• Thromboembolism as a result of ingress of air or the development of atherosclerosis;
• Severe aspiration of gastric contents;
• Myocardial infarction, pericardial tamponade;
• Septic shock;
• Edema of the lungs and other signs not associated with allergies.

Emergency treatment with rapidly developing both anaphylactic and anaphylactoid reactions does not differ from the set of actions aimed at eliminating and treating anaphylactic shock.

The order of urgent actions

With the progression of the allergy, the qualification of medical professionals and the provision of assistance in the near future is the key to successful treatment. The main measures for the relief of anaphylaxis of immediate type consist in the obligatory passage of several stages:

1. The introduction of an unconfirmed, but potentially dangerous antigen should be discontinued.
2. Anaphylactic or anaphylactoid reaction (photos in the article clearly demonstrate the most common manifestations and signs of pathology), developing during anesthesia or during surgery, requires immediate suspension. A qualitative test should be carried out on the fact of the introduction of allergens. With a sharp jump in blood pressure down, it is necessary to interrupt the supply of anesthetic. In the case of bronchospasm, inhalation anesthetics are mandatory.
3. Ventilation and airway patency should be ensured even at a stage when the patient's condition has not significantly deteriorated. In intubation, the lungs need constantly, until it becomes finally clear that the airway is provided by the body on its own.
4. Anaphylactoid reaction, the treatment of which requires intravenous adrenaline, is dangerous for the patient even after several hours after the removal of bronchospasm. Dosage of epinephrine with repeated administration can be increased, since this substance positively affects the stabilization of mast cells, a decrease in the permeability of the endothelium of blood vessels, which is extremely important in the treatment of anaphylaxis.
5. With the urgent need for resuscitation, it is also important to increase the volume of circulating fluid in the body. To this end, doctors put a catheter of considerable diameter intravenously (the vein used can not always be central - time to search for it can play against the patient's condition) and pour in a few liters of crystalloids.
6. If it is impossible to detect allergens that caused an anaphylactoid reaction, it is worth paying attention to the use of latex objects during contact with the patient. Surgical gloves, drugs collected through latex cap vials, urinary catheters - all this could provoke anaphylaxis.

After an emergency treatment, anaphylactoid reaction (as well as anaphylactic reaction) requires a prolonged therapeutic course in order to prevent repeated occurrences of pathology. Neglect of doctors' instructions increases the risk of expanding the range of potential allergens.

Follow-up treatment

Among the medication program for the therapy of bronchospasm, an important role belongs to the drug "Salbutomol", it can be replaced by "Aminophylline". If possible, then additionally resort to inhalation with isoproterenol or orciprenaline. Because the anaphylactoid reaction is a clinical systemic manifestation in which the symptoms can be complex, it is necessary to use glucocorticoids (for example, "Dexamethasone", "Hydrocortisone") that inhibit the process of cardiovascular collapse.

Usually, the relief of anaphylactic shock is followed by a prolonged watchfulness of the doctors. The fact is that the development of late dysfunctions can always take place, therefore, for any degree of severity of the patient's condition, hospitalization is an unequivocal decision. Obligatory doctors also consider the forthcoming examination of the skin for the detection of specific antibodies.

Prevention of anaphylactic and anaphylactoid reactions

The thorough collection of anamnesis is the best measure to prevent and prevent re-anaphylaxis. Having collected all the necessary information about the course of the disease, it is possible to isolate the patient from the risk group and determine what he will be threatened with a second anaphylactoid reaction. What does it mean?

Because each subsequent attack can be much more difficult, patients need a thorough selection of drugs in both anesthesia and intensive care. Before the blood transfusion, people prone to anaphylaxis are tested for compatibility with certain blood products.

The presence of an allergy to latex products predetermines in the future the conduct of various manipulations without the use of such means.