Agent-induced anaphylaxis

Incidences of Drug- and Other Agent-Induced Anaphylaxis During Anesthesia... 

Although specific antisera have proven invaluable in the treatment of a variety of medical conditions (Table 13.1), they can also induce unwanted side effects. Particularly noteworthy is their ability to induce hypersensitivity reactions some such sensitivity reactions (e.g. serum sickness ) are often not acute, whereas others (e.g. anaphylaxis) can be life threatening. Because of such risks, antibody preparations derived from human donors (i.e. immunoglobulins) are usually preferred as passive immunizing agents. 

Mechanism of Action An antiasthmatic and antiallergic agent that prevents mast cell release of histamine, leukotrienes, and slow-reacting substances of anaphylaxis by inhibiting degranulation after contact with antigens. Therapeutic Effect Helps prevent symptoms of asthma, allergic rhinitis, mastocytosis, and exercise-induced bron-chospasm. 

Histamine is released from mast cells in antigen-antibody reactions, as in anaphylaxis and allergy, which are the most widely known physiological reactions to histamine. However, these potentially fatal reactions are not caused by histamine alone. Other agents present in mast cells, such as serotonin, acetylcholine, bradykinin (a nonapeptide), and a slow-reacting substance or leukotriene (see chapter 8) also contribute. In the stomach, where histamine induces acid secretion, its release seems to be regulated by the peptide hormone pentagastrin. 

Stimulated platelets release arachidonic acid rapidly from their phospholipids, apparently as a result of activation of phospholipase A2. The released arachidonate can in turn be metabolized to endoperoxides and thromboxane A2 (Chapter 21). These compounds are also potent activators of platelets and cause a self-activating or autocrine effect.1) While PAF has a beneficial function, it can under some conditions contribute in a dangerous way to inflammation and to allergic responses including anaphylaxis,) asthmag and cold-induced urticaria.1 Although the effect of PAF is separate from those of histamine and of leukotrienes, these agents may act cooperatively to induce inflammation.1... 

The case history and other clinical manifestations in some of the patients with reactions to suxamethonium leaves little doubt that allergy can develop in response to the administration of this agent, which is an acetylcholine analogue. The acute reaction in these cases was therefore very likely to have been due to typical IgE-mediated anaphylaxis. Cases of similar reactions have been reported by other authors, e.g. Jerums et al. (1967), Royston and Wilkes (1978). This aspect, the immune reaction to succinylcholine is considered so fundamentally important as to warrant full consideration. The preliminary studies of Hadji and Benveniste (1980) suggest that sensitization of guinea-pigs to suxamethonium can be induced by repeated injection. 

Many different pharmaceutical products have been reported to cause contact urticaria, mostly of the immunologic type. Sometimes, oculorhinitis, respiratory symptoms or even anaphylaxis can develop. Because of the powdered nature of several pharmaceutical products, the causative agent may induce cutaneous symptoms by direct contact or through an airborne mechanism. The most frequent agents causing contact urticaria in this occupational group are latex and medicaments, especiaUy antibiotics [218, 242-244] (Table 6). 

---