Urticaria, allergic manifestation

In rare instances, urticaria has followed exposure to lindane vapor. Unlike the signs and symptoms already mentioned, this allergic manifestation occurs only in... 

It is frequently used in mild, local allergic reactions due to insect bites. It possesses sedative, antiemetic and anti-tussive properties and can be used in seasonal allergic rhinitis, allergic manifestations due to urticaria and allergic conjunctivitis of inhalant allergens. 

The drug is used invariably in the symptomatic relief of urticaria, hay fever, and a few other allergic manifestations. 

Positive patch tests to phenolphthalein have been reported in some eczematous lesions (Bernstein 1931 Wise and Sulzberger 1933). False positive patch tests, reflecting epidermal hysteresis, have also been demonstrated after phenolphthalein administration (Shelley et al. 1972). Wyatt et al. (1972) found that serum taken during exacerbations produced a local inflammation when injected intradermally. Possible cross-reaction with erythrosin which is used as a food and drug colorant has been reported (Wile 1936). Other rare allergic manifestations after phenolphthalein administration are urticaria, Stevens-Johnson syndrome, lupus erythe-matosus-like eruptions, and encephalitis (Lindemayr 1959 Kendall 1954). 

Type I. Anaphylactic immediate hypersensitivity. The allergen reacts with tissue cells, such as mast cells or basophils that have been sensitized by antibody, which release vasoactive substances into the bloodstream. Anaphylaxis, which is characterized by an immediate (within 15 minutes) vasoconstriction, bronchoconstriction, shock, and in severe cases, death, is a Type I reaction, as are angioedema (vascular engorgement) and atopy. Atopy, a syndrome mediated by Type I reactions, is a genetic susceptibility to such allergic manifestations as hay fever, eczema, asthma, and urticaria (hives). 

ATOPY A SYNDROME resulting from a genetic susceptibility to allergic manifestations. Symptoms include hay fever, ECZEMA, asthma, and URTICARIA. 

Only nine allergic reactions to cuttlefish have been described (Caffarelli et ah, 1996 Ebisawa et ah, 2003 Shibasaki et ah, 1989). One patient was a 10-year-old female who experienced a severe reaction to ingestion of cuttlefish that was manifested by urticaria, angioedema, asthma, abdominal pain, laryngeal edema, and hypotension (Shibasaki et ah, 1989). SPT and RAST were positive. This patient reportedly tolerated octopus, clam, oyster, abalone, mussel, and scallop but reacted to crab and shrimp. Caffarelli et ah (1996) describe a 14-year-old female who had cuttlefish-dependent, exercise-induced anaphylaxis. Ebisawa et ah (2003) reported 7 cases of allergy to cuttlefish among a series of 305 pediatric cases of food allergy but provided no specifics on the circumstances or symptoms of these patients. 

The circulatory effects are manifested as arteriolar dilation and increased capillary permeability, causing plasma loss. The localized redness, edema (hives, wheal), and diffuse redness seen in allergic urticaria (rash) or physical skin injury result from these circulatory changes. Vasodilation also causes a decrease in blood pressure. 

Allergic reactions manifesting as fever, urticaria or other rashes, and arthralgia occur in 1-5% of patients taking antithyroid drugs. There has been a report of thiamazole-induced hypersensitivity syndrome associated with reactivation of human herpes virus 6 and cytomegalovirus (57). 

The methods for assessing reactivity previously outlined are simple, convenient, inexpensive, and noninvasive or minimally invasive 6 However, cutaneous reactivity depends on many factors. None of the previous methods give a full picture of the characteristics of sensitive skin, only susceptibility of skin to irritants. Subtle manifestations of endogenous cutaneous conditions must still be clinically excluded. Exclusion of allergic contact dermatitis must still be performed by patch testing, exclusion of contact urticaria by open tests or PUT/ROAT, and exclusion of photoallergy by photopatch testing. 

There is steady growing evidence that environmental exposure to insects at home and in the workplace are the frequent causes of allergic sensitization (Arlian 2002). Subsequently clinical symptoms are mainly of respiratory nature, manifested in allergic rhinitis, asthma, and urticaria (Steen et al. 2004), and in some documented cases also via ingestion, causing systemic anaphylaxis. 

Allergic responses to drugs are mediated by the release of histamine or histamine-like substances, and they commonly present as skin rashes, particularly urticaria. More serious hypersensitivity responses include bronchospasm or the acute, explosive anaphylactic reaction with cyanosis and cardiovascular collapse. A delayed reaction known as serum sickness, although more often associated with such drugs as the penicillins and cephalosporins rather than with serum, manifests clinically 7 to 10 days after receiving the drug or serum as fever, malaise, joint pains, and urticarial skin rashes. 

Although there are five types of hypersensitivity responses, two of these, types 1 and 1 play a significant role in the pathophysiology of allergic eye disease. The ocular manifestations include seasonal allergic conjunctivitis (SAC), giant papillary conjunctivitis (GPC), vernal keratoconjunctivitis (VKC), atopic keratoconjunctivitis, contact dermatitis, and urticaria. These are discussed in Chapter 27. 

Allergic disorders of the eyelid include atopic dermatitis, contact dermatitis, and urticaria. Eczema is a common feature of both atopic and contact dermatitis.Table 27-5 summarizes the clinical manifestations and management of each entity. 

Type I reactions are IgE mediated and cause manifestations of allergic symptoms due to the release of immune mediators such as histamine or leukotrienes. These reactions typically occur within minutes of drug exposure and may manifest as generalized prurituS/ urticaria/ angioedema/ anaphylaxiS/ rhinitiS/ or conjunctivitis (21). Anaphylaxis can result from exposure to any antigen (e.g./ penicillin) and may be fatal in the absence of prompt medical intervention. 

Human As noted above in acute and subchronic effects, local anesthetics can produce an allergic syndrome that can manifest as urticaria in some patients. This nearly always occurs with amide anesthetics so changing to amine anesthetics greatly reduces this side effect. 

Cetirizine competitively antagonizes histamine at the Hi-receptor site and is indicated in the symptomatic relief of symptoms (e.g., nasal, nonnasal) associated with seasonal and perennial allergic rhinitis treatment of uncomplicated skin manifestations of chronic idiopathic urticaria. Histamine is a potent vasodilator, bronchial smooth-muscle constrictor, and stimnlant of nociceptive itch nerves. In addition to histamine, mnltiple chemical itch mediators can act as pruritogens on C-fibers, including neuropeptides, prostaglandins, serotonin, acetylcholine, and bradykinin. Furthermore, new receptor systems such as vanilloid, opioid, and canna-binoid receptors on cutaneous sensory nerve fibers that may modulate itch offer novel targets for antipruritic therapy. 

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