The occurrence of an allergic (anaphylactic) reaction is caused by exogenous agents, and its course is characterized by immediate hypersensitivity. As a rule, the body's response can be characterized by a 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 intended purpose, begins. They merge with the cells responsible for the immunological processes in the body, and sensitization to the antigen occurs.
How do allergic reactions manifest?
The next hit of the allergen promotes the release of bioactive substances, in particular histamine, from the cells responsible for immune forces.
At the moment of transition from pathological chemical processes to unnatural physiology, changes are reflected primarily in blood vessels, lymph nodes, smooth bronchial muscles, which contributes to the development and early manifestation of the following syndromes:
- decrease in vascular tone;
- sudden reductionsmooth muscle tissues of the intestines, bronchi, uterus;
- bleeding disorders;
- inflammation and swelling of blood vessels.
Unlike allergic, anaphylactoid reaction, which doctors often call pseudo-allergic, IgE antibodies are not mediated by basophils. Despite the similarity of the manifestation of response processes, both manifestations are a generalized response of the body's hypersensitivity.
Medicinal allergens causing anaphylactoid reactions
An anaphylactoid reaction is also the release of histamine, often already at the first contact with an irritant. Pseudoallergens currently represent a fairly wide range. Paradoxically, this reaction of the body often happens while taking drugs that stop allergies.
Immediate anaphylactic and anaphylactoid reactions are fairly common after administration of muscle relaxants, antibiotics, anesthetics, opioids, local pain medications, vaccinations, hormone therapy, atropine, and B vitamins. Allergens also include sera, antigens used for medical diagnostic purposes to detect skin, venereal diseases. Allergies to latex products have increased.
An anaphylactoid reaction to lidocaine is considered a common occurrence, since the drug is often used in local anesthesia, but its complex chemical composition can cause side effects even ina he althy body, for which an allergy to the components of the drug is not typical.
Non-drug irritants
If we consider cases of the body's responses to non-drug stimuli, then food can be mainly "problematic" here:
- strawberry;
- crustaceans;
- honey;
- nuts;
- mushrooms;
- fish of some varieties;
- eggs;
- citrus.
An anaphylactoid reaction can occur when bitten by an insect or poisonous invertebrate representative of the fauna. Patients who constantly experience non-drug allergic manifestations are at great risk of developing anaphylaxis if surgery is performed under general anesthesia.
Classification of anaphylaxis
This is where the classification of allergic reactions comes from. The first block includes varieties of anaphylactic reactions, which are divided into mediated by IgE, mediated by IgG and mediated by IgE and exercise. Anaphylactoid pseudo-allergic reactions are mediated by simple release of mediators, then should be called provoked by the actions of drugs, food and physical factors.
Anaphylactoid reactions in mastocytosis are a separate category; mediated by immune complexes, immunoglobulin aggregates when administered with immune sera and mediated by cytotoxic antibodies, radiopaque agents.
How does anaphylaxis progress?
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 entry into the body of active substances. Practice shows that the reaction is predominantly benign, limited only to manifestations on the skin.
Anaphylactoid reaction (ICD 10 assigned to this pathological syndrome) is characterized by the unpredictability of further development and, possibly, the complete absence of information about previous allergic responses of the body to antigens. Since the consequences of anaphylaxis are dangerous to he alth and life, it is important to detect the course of complications in a timely manner and take appropriate measures. Regardless of the mechanism of an anaphylactic or pseudo-allergic stimulus, symptoms can vary significantly. Wearing a purely individual character, the manifestations can range from a slight jump in blood pressure and skin rashes to severe bronchospasm and collapse of the functioning of the cardiovascular system.
At this stage, it is easy to note one more difference in the effect 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 an anaphylactoid reaction
Signs of an allergic reaction in an awake patient are:
- dizziness;
- general weaknessorganism;
- violation of heart rhythms (tachycardia, arrhythmia);
- lowering blood pressure;
- difficulty breathing, asthma attacks, bronchospasm and laryngospasm, pulmonary and laryngeal edema;
- burning skin, itchy rashes, urticaria, hyperemia of the integument, Quincke's edema;
- intestinal cramps, nausea, diarrhea, vomiting;
- no pulse;
- cardiovascular collapse;
- slow down and stop the heart.
Possible complications after an anaphylactoid reaction
The greatest threat 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 (oral or parenteral).
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 functions, 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 high. Often, after anaphylactic shock, doctors diagnose such dysfunctions anddiseases:
- pneumonia;
- vasculitis;
- renal and liver failure, hepatitis, glomerulonephritis;
- epidermal necrolysis;
- myocarditis;
- arthritis.
Such consequences can be threatened by both anaphylactic and anaphylactoid reactions. The difference from anaphylactic shock of these pathologies is that the latter requires prior sensitization and is not able to develop at the first meeting with an allergen substance.
Anaphylaxis treatment
Only anamnesis will help to correctly draw up an emergency treatment regimen according to the diagnosis, so it is extremely important to collect it.
Allergy symptoms, i.e. the clinical picture, also play a significant role in making a speedy decision. However, the most reliable and complete answer to the question of making a diagnosis can be obtained only after allergists and immunologists conduct a laboratory study. At the same time, based on the critical condition of the patient, first of all, he should be provided with emergency medical care, and in case of cardiac or respiratory arrest, resuscitation.
At the stage of recognizing the root causes of the body's allergic response, the task of physicians is to conduct a detailed differential diagnosis. This type of examination is designed to exclude possible factors of influence that are not related to the release of histamine.
Similar body reaction to other non-allergic causes
Most oftenanaphylactic and anaphylactoid reaction (what is it and why pathologies are dangerous, it is important to know for people who are prone to even the most harmless, at first glance, allergic manifestations in the form of rhinitis) are similar to other factors that can potentially cause bronchospasm, hypotension:
- anesthetic overdose;
- thromboembolism as a result of air entry or development of atherosclerosis;
- severe gastric aspiration syndrome;
- myocardial infarction, pericardial tamponade;
- septic shock;
- pulmonary edema and other signs not related to allergies.
The provision of emergency care for rapidly developing both anaphylactic and anaphylactoid reactions practically does not differ from the set of actions aimed at eliminating and treating anaphylactic shock.
Urgent Action Order
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 the immediate type are the mandatory passage of several stages:
- The introduction of an unconfirmed but potentially dangerous antigen must be stopped.
- Anaphylactic or anaphylactoid reaction (photos in the article clearly demonstrate the most common manifestations and signs of pathology), which develops during anesthesia or during surgery, requires immediate suspension. Must bea qualitative check for 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 case of bronchospasm, inhalation anesthetics are mandatory.
- Ventilation and airway patency must be ensured 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 patency provided by the body on its own.
- Anaphylactoid reaction, the treatment of which requires intravenous 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, reducing the permeability of the endothelium of blood vessels, which is extremely important in the treatment of anaphylaxis.
- When there is 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 - the time to find it can play against the patient's condition) and pour several liters of crystalloids.
- 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 drawn through latex capsvials, urinary catheters - all this could provoke anaphylaxis.
After emergency treatment, an anaphylactoid reaction (as well as an anaphylactic reaction) requires a long therapeutic course in order to prevent recurrence of the pathology. Neglecting the instructions of doctors increases the risk of expanding the range 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, they additionally resort to inhalation with isoproterenol or orciprenaline. Since an anaphylactoid reaction is a clinical systemic manifestation in which symptoms can be complex, it is necessary to use glucocorticoids (for example, Dexamethasone, Hydrocortisone), which inhibit the process of cardiovascular collapse.
Usually, the relief of anaphylactic shock is accompanied by a subsequent prolonged alertness of doctors. The fact is that the development of late dysfunctions can always take place, therefore, with any degree of severity of the patient's condition, hospitalization is an unequivocal decision. Doctors also consider the upcoming skin examination to detect specific antibodies to be mandatory.
Prevention of anaphylactic and anaphylactoid reactions
A thorough history taking is the best measure to prevent and prevent recurrent anaphylaxis. Having collected allnecessary information about the course of the disease, it is possible to identify the patient from the risk group and determine what threatens him with a repeated anaphylactoid reaction. What does this mean?
Because each subsequent attack can be much more severe, patients require careful selection of drugs both under anesthesia and during intensive care. Before a blood transfusion, people prone to anaphylaxis are tested for compatibility with certain blood products.
The presence of an allergy to latex products predetermines various manipulations in the future without the use of such products.
