The occurrence of an allergic (anaphylactic) reaction is caused by exogenous agents, and its course is characterized by immediate hypersensitivity. As a rule, the response of the body can be characterized by the life-threatening pathological condition of the skin, respiratory and cardiovascular functions. After the first contact with the antigen, the production of IgE antibodies specific for their 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 exposure to the allergen promotes the release of bioactive substances from the cells responsible for the immune forces, in particular histamine.
At the time of the transition from pathological chemical processes to unnatural physiology, changes are reflected primarily in the 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 intestines, bronchi, uterus;
- bleeding disorders;
- inflammation and edema of blood vessels.
Unlike allergic ones, the anaphylactoid reaction, which doctors often call pseudo-allergic, IgE antibodies are not mediated with basophils. Despite the similarity of the manifestations of the response processes, both manifestations are a generalized response of the hypersensitivity of the body.
Anaphylactoid drug allergens
Anaphylactoid reaction is also the release of histamine, often already at the first contact with the stimulus. Pseudo-allergens at the moment represent a fairly wide range. Paradoxically, this reaction of the body often happens while taking drugs that stop allergies.
Anaphylactic and anaphylactoid reactions of the immediate type occur quite often after the introduction of muscle relaxants, antibiotics, anesthetics, opioids, local painkillers, vaccinations, hormone therapy, atropine and B vitamins. Allergens also include serums, antigens used for medical and diagnostic purposes to detect skin, sexually transmitted diseases. Cases of allergies to latex products have become more frequent.
An anaphylactoid
reaction to lidocaine is considered a common phenomenon
, since the drug is often used in local anesthesia, but its complex chemical composition can cause side effects even in a healthy body, for which an allergy to the components of the drug is not characteristic.
Non-medicinal irritants
If we consider the cases of response of the body to irritants of non-drug nature, then here the food can be mainly “problematic”:
- wild strawberries;
- crustaceans;
- honey;
- nuts
- mushrooms;
- fish of some varieties;
- eggs
- citrus.
Anaphylactoid reaction can occur with a bite of an insect or invertebrate poisonous representative of the fauna. Patients who are constantly experiencing allergic manifestations of a non-drug nature have huge risks of developing anaphylaxis in the case of surgery under general anesthesia.
Classification of Anaphylaxis
From here comes the classification of allergic reactions. The first block includes a variety of anaphylactic reactions, which are divided into mediated IgE, mediated IgG and mediated IgE and physical activity. Anaphylactoid pseudo-allergic reactions are mediated by the simple selection of mediators, then it should be called provoked by the actions of drugs, exposure to food and physical factors.
Anaphylactoid reactions in mastocytosis are a separate category; mediated by immune complexes, immunoglobulin aggregates with the introduction of immune sera and mediated by cytotoxic antibodies,
radiopaque substances.How does anaphylaxis occur?
Morphine and many barbiturates, muscle relaxants, pethidine can act on mast cells, causing the release of histamine. In this case, the clinical picture depends on the dosage and the rate of intake of active substances in the body. Practice shows that mainly 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, a complete lack of information about the body's previous allergic responses to antigens. Since the consequences of crane anaphylaxis are dangerous to health and life, it is important to timely detect the course of complications and take appropriate measures. Regardless of the mechanism of anaphylactic or pseudo-allergic stimulus, the symptoms 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 the collapse of the functioning of the cardiovascular system.
At this stage, it is not difficult to note another difference in the action of pseudo-allergens on the body. Meanwhile, an anaphylactoid reaction, the symptoms of which can be detected individually or appear in various combinations, is no less dangerous.
Symptoms of anaphylactoid reaction
Signs of an allergic reaction in a patient awake are:
- dizziness;
- general weakness of the body;
- violation of heart rhythms (tachycardia, arrhythmia);
- lowering blood pressure;
- shortness of breath, asthma attacks, bronchus and laryngospasm, pulmonary edema and larynx;
- skin burning, itchy rashes, urticaria, hyperemia of the integument, Quincke's edema;
- intestinal cramps, nausea, diarrhea, vomiting;
- lack of pulse;
- cardiovascular collapse;
- slowing and stopping the work of the heart.
Possible complications after anaphylactoid reaction
The greatest threat in itself is fraught with shock, combined with bronchospasm. After a certain period of time (from 30 seconds to half an hour, sometimes 2-3 hours), the antigen that has entered 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, resulting in a sharp circulatory failure, cerebral edema or hemorrhage, impaired stem function, arterial thrombosis.
On the second day after the shock, a 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 developing complications remains high. Often, after anaphylactic shock, doctors diagnose such dysfunctions and diseases:
- pneumonia;
- vasculitis;
- renal and liver failure, hepatitis, glomerulonephritis;
- epidermal necrolysis;
- myocarditis;
- arthritis.
Both anaphylactic and anaphylactoid reactions can threaten such consequences. The difference from the anaphylactic shock of these pathologies is that the latter requires preliminary sensitization and is not able to develop at the first meeting with an allergen substance.
Anaphylaxis Treatment
It is true to draw up an emergency treatment regimen according to the diagnosis only an anamnesis will help, therefore it is extremely important to collect it.
Symptoms of allergies, i.e., the clinical picture, also play a significant role in making an early decision. However, the most reliable and complete answer to the question about the diagnosis can be obtained only after allergologists and immunologists conduct laboratory tests. In this case, based on the
critical condition of the patient, first of all, he should be given emergency medical care, and in case of cardiac arrest or breathing - resuscitation.
At the stage of recognition of the root causes of the allergic response of the body, the task of doctors is to conduct a detailed differential diagnosis. This type of examination is intended to exclude probable exposure factors not related to histamine release.
A similar reaction of the body to other non-allergic causes
Most often, an anaphylactic and anaphylactoid reaction (what are these and why are pathologies dangerous, it is important to know for people prone to even the most harmless, at first glance, allergic manifestations in the form of rhinitis) have similarities with other factors that can potentially cause bronchospasm, hypotension:
- an overdose of anesthetics;
- thromboembolism as a result of air or the development of atherosclerosis;
- severe aspiration syndrome of gastric contents;
- myocardial infarction, pericardial tamponade;
- septic shock;
- pulmonary edema and other signs not associated with allergies.
The provision of emergency care with rapidly developing both anaphylactic and anaphylactoid reactions practically does not differ from the complex of actions aimed at eliminating and treating anaphylactic shock.
Urgent Action
With the progression of allergies, the qualification of doctors and the provision of assistance as soon as possible is the key to successful treatment.
The main measures to stop anaphylaxis of an immediate type are the mandatory passage of several stages:
- The administration of an unconfirmed but potentially dangerous antigen must be discontinued.
- Anaphylactic or anaphylactoid reaction (the photo in the article clearly shows the most common manifestations and signs of pathology), developing during anesthesia or during surgery, requires immediate suspension. A qualitative check should be made on the fact of the introduction of allergens. With a sharp jump in blood pressure down, it is necessary to interrupt the flow of anesthetic. In case of bronchospasm, inhaled anesthetics are mandatory.
- Ventilation and airway should be provided even at the stage when the patient's condition has not significantly worsened. The lungs need intubation constantly, until it becomes completely clear that the airway is provided by the body on its own.
- Anaphylactoid reaction, the treatment of which requires intravenous administration of adrenaline, is dangerous for the patient even several hours after the elimination of bronchospasm. The dosage of adrenaline with repeated administration can be increased, since this substance has a positive effect on the stabilization of mast cells, a decrease in the permeability of the blood vessel endothelium, which is extremely important in the treatment of anaphylaxis.
- With an 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 a significant diameter intravenously (the vein used may not always be central - time to search for it can play against the patient’s condition) and several liters of crystalloid are poured.
- If it is impossible to detect allergens due to which an anaphylactoid reaction has occurred, it is worth paying attention to the use of latex objects during contact with the patient. Surgical gloves, drugs scored through latex bottle caps, urinary catheters - all this could trigger anaphylaxis.
After emergency treatment, an anaphylactoid reaction (as well as anaphylactic) requires a long therapeutic course in order to prevent recurrence of the pathology. Neglecting the instructions of doctors increases the risk of expanding the circle of potential allergens.
Follow-up treatment
Among the drug program for the treatment of bronchospasm an important role belongs to the drug "Salbutomol", it can be replaced by "Aminophylline". If possible, then they additionally resort to inhalation with isoproterenol or orciprenaline. Since the anaphylactoid reaction is a clinical systemic manifestation in which the symptoms can be complex, glucocorticoids (for example, Dexamethasone, Hydrocortisone), which inhibit the process of cardiovascular collapse, must be used.
Usually, relief of anaphylactic shock is accompanied by subsequent prolonged alertness of 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 a definite solution. Doctors also consider the upcoming skin examination to detect specific antibodies mandatory.
Prevention of anaphylactic and anaphylactoid reactions
A thorough history taking is the best measure of prevention and prevention of repeated 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 repeated anaphylactoid reaction. What does it mean?
Since each subsequent attack can be much more difficult, patients require a thorough selection of drugs during anesthesia and during intensive care. Before blood transfusion, people prone to anaphylaxis are tested for compatibility with certain blood products.
The presence of an allergy to latex products determines the future of various manipulations without the use of such tools.