Drug allergy in children

Drug allergy in children is a unifying concept for reactions and diseases caused by the use of medications and caused by immunopathological mechanisms.

Pseudoallergic reactions may arise due to the fact that the medicine causes the release of biogenic amines (histamine, etc.) without the previous immunological stage. Pseudoallergic reaction can cause acetylsalicylic acid, stimulating the lipoxygenase pathway of prostaglandin synthesis, activating complement without antibodies.

[1], [2], [3], [4], [5], [6]

What causes a drug allergy in children?

Of antibiotics, most often the drug allergy in children develops to penicillin, streptomycin, tetracyclines, less often - cephalosporins. In addition to antibiotics, allergic reactions can manifest themselves to sulfonamides, amidopyrine, novocaine, bromides; drugs containing iodine, mercury, B vitamins. Often, drugs become allergens after oxidation or cleavage with prolonged storage under inappropriate conditions. The most dangerous is the parenteral route of administration of the drug, especially during the period of gastrointestinal diseases in young children, against the background of food allergy, with the development of dysbacteriosis. The properties of medicines, their high biological activity, chemical characteristics of the preparation (proteins and their complex compounds, polysaccharides), physical properties of the preparations (good solubility in water and fats) are important. Predispose to a drug allergy suffered by allergic and infectious diseases, insufficiency of the functions of excretory systems of the body.

According to several authors, about 5% of children go to hospitals due to the undesirable consequences of drug therapy. Determined that:

• the frequency of complications of drug therapy is directly proportional to the number of prescribed medications;
• hereditary and family characteristics are crucial in the occurrence of complications of therapy by a certain group of drugs;
• the undesirable effects of drugs largely depend on their pharmacological properties, the state of the organs where the drug is absorbed (the gastrointestinal tract), metabolized (liver or other organ), or excreted (kidneys, etc.), and therefore their frequency of toxic effects increases;
• infringement of rules of storage, terms of realization of medicines and a selftreatment increase frequency of complications of medicinal therapy.

All the undesirable effects of drugs are divided into two large groups.

1. Predictable (approximately 75-85% of all patients with complications of drug therapy):
   • toxic effects of the drug may be due to an overdose, a violation of its metabolism, excretion, hereditary or acquired lesions of different organs, combined drug therapy;
   • side effects of drugs associated with their pharmacological properties are often unavoidable, because the drug acts not only on the organ whose damage it is assigned, but also on others; an example may be the M-cholinolytic and sedative effect of H2-histaminoblockers, CNS stimulation in the appointment of euphyllin in connection with an attack of bronchial asthma, suppression of leukopoiesis in cytostatic therapy;
   • secondary effects that are not related to the underlying pharmacological action, but occur frequently; for example, intestinal dysbiosis after antibiotic treatment.
2. Unpredictable:
   • drug allergy;
   • idiosyncrasy - the genetic characteristics of the patient's metabolism, which determine the intolerance of the drug and its side effects; for example, hemolytic crisis in patients with hereditary deficiency of G-6-PD can occur after taking antipyretics and antimalarials, sulfonamides, naphthoquinolones.

Causes of a drug allergy

Symptoms of drug allergy in children

The medicinal allergy in children displays the following symptoms:

• systemic allergic reactions (anaphylactic shock, erythema multiforme exudative, bullous epidermolysis, including epidermal necrolysis);
• various allergic skin lesions (hives, contact dermatitis, fixed eczema, etc.);
• allergic lesions of the mucous membranes of the mouth, tongue, eyes, lips (stomatitis, gingivitis, glossitis, cheilitis, etc.);
• pathology of the gastrointestinal tract (gastritis, gastroenteritis).

Less commonly, the drug allergy is diagnosed in children as hapten granulocytopenia and thrombocytopenia, hemorrhagic anemia, respiratory allergies (asthma attack, sublingual laryngitis, eosinophilic pulmonary infiltrate, allergic alveolitis). Even more rarely is a drug allergy in children as a consequence of myocarditis, nephropathy, systemic vasculitis, nodular periarteritis and lupus erythematosus.

Symptoms of a drug allergy

Diagnosis of drug allergies in children

The basis is a carefully analyzed history. The variety of forms of immune response induced by drugs, the lack of appropriate antigens (which is associated with metabolic changes in drugs in the body) prevent the development of diagnostic tests acceptable for the clinic. Conducting skin tests is dangerous for the patient.

From laboratory tests, the detection of specific IgE antibodies (PACT) to penicillin, co-trimoxazole, muscle relaxants, insulin is used; specific IgG and IgM; blattransformation reaction of lymphocytes; the determination of tryptase released by the activation of mast cells by a drug.

Obtaining a positive result of skin testing or laboratory methods of investigation suggests that the patient is at risk for a reaction to a drug, but a negative result does not exclude the possibility of a clinical response to the administration of the drug.

[7], [8], [9], [10]

Treatment of drug allergies in children

If you suspect a child of allergic treatment, first of all it is necessary to cancel all the drugs that the child received.

Drug allergies in children, taking place in the form of acute reactions are treated with the help of gastric lavage, the appointment of salt laxatives, the reception of enterosorbents (for example, activated charcoal, polyphepan and others), antiallergic medicines.

More severe symptoms require immediate hospitalization, the appointment of bed rest, plenty of drinking.

How is drug allergy treated?

How is drug allergy prevented in children?

Primary prevention is reduced to extreme alertness in the choice of indications for drug therapy, especially in children with atopic diathesis and allergic diseases.

Secondary prophylaxis is to prevent the introduction of a drug, which the child has already given an allergic reaction.

Information on the first allergic reaction should be written in red letters on the obverse side of the out-patient history of the development and medical history in the hospital.

Parents and older children should be informed of the adverse reaction to the drug.