Cross-reactions skin test

In cases of local reactions, skin tests should not be performed, since they are rarely helpful in detecting potential cross-reactivity between low molecular weight heparin and heparin (65,71). 

Numerous positive delayed skin tests in patients with contrast medium-induced non-immediate skin reactions have been reported when the patients were tested with the culprit contrast medium [summarized in 1]. In a large European multicenter study, 37% of patients with non-immediate reactions were positive in delayed IDEs and/or patch tests [13]. The majority of the patients also reacted to the culprit contrast medium and also to other, structurally similar RCM. Notably, in more than 30% of those skin test-positive patients a RCM had been administered for the first time. Thus, there is a lack of a sensitization phase. Again it may be hypothesized that these previously non-exposed patients may have already been sensitized. Different patterns of RCM cross-reactivity indicate that several chemical entities could be involved. No positive skin tests have been obtained with other contrast medium excipients, such as ethylenediaminetetraacetic acid (EDTA), and only rarely patients have been found to react to inorganic iodide. 

The further allergologic workup is recommended to be performed between 2 and 6 months after the reaction (table 3) [13]. A skin prick test should be performed with undiluted RCM. Afterwards, IDTs with RCM (300-320 mg/ml) diluted 10-fold in sterile saline and reading after 20 min are recommended [13]. As cross-reactivity is frequent, a panel of several different RCM should be tested in an attempt to find a skin test-negative product, which might be tolerated in future RCM examinations. 

Bisphenol A causes slight skin and eye irritation. It did not cause contact allergy in a guinea pig maximization test. Furthermore, no cross-reactions were detected when animals sensitized to the diglycidyl ether of bisphenol A were tested with bisphenol A. 

A 27-year-old woman, a pharmacist, had dermatitis on three separate occasions a few hours after she started to take oral deflazacort 6 mg for vesicular hand eczema (185). On each occasion, her symptoms included a widespread macular rash mainly on the inner aspects of her arms and legs and buttocks. She also had severe scaling, fever, nausea, vomiting, malaise, and hypotension. A skin biopsy was consistent with erythema multiforme, and direct immunofluorescence showed granular deposits at the dermoepidermal junction. Patch tests to the commercial formulation of deflazacort 6 mg (1% aqueous solution) and to pure deflazacort (1% aqueous solution) were positive, but there were no cross-reactions to other glucocorticoids. 

A female florist from North Germany, who ran a flower shop from 1954 to 1966 had to quit her job because of contact allergy to chrysanthemums and primrose. After a further 12 years she started to suffer occasionally from redness of the pharynx and stomachache after drinking tea prepared from yarrow and camomile. Skin tests were positive to chrysanthemum with cross-reactions to sunflower, arnica, camomile. 

There was a high degree of cross-reactivity between imipenem determinants, analogous to the penicillin determinants in penicillin-allergic patients. Nine of twenty patients with positive penicillin skin tests had positive skin reactions to analogous imipenem determinants (40). In view of this appreciable cross-reactivity, imipenem should not be given to patients with penicillin allergy. 

Although anaphylactic reactions without any documented immune-mediated mechanism have been reported in about 8% of patients with testicular cancer given GM-CSF (48), GM-CSF has only otherwise rarely been associated with allergic reactions. Of two patients who had possible immune-mediated reactions (SEDA-19, 342) one had an immediate recurrent local reaction followed by systemic hypersensitivity reaction after sargramostim, and the other had a maculopapular pruritic eruption after molgramostim. Cross-reaction between the two recombinant forms of GM-CSF was suggested by the results of skin prick tests in one patient, but both patients thereafter tolerated filgrastim uneventfully. 

Treatment of these problems is by substituting another insulin species which does not cross-react with the antibodies, by desensitization, or by local or systemic administration of glucocorticoids. If a severe allergic reaction occurs, the drug has to be discontinued and the patient treated with the usual agents (e.g. adrenaline, antihistamines or corticosteroids). Patients who have experienced severe systemic allergic symptoms should be skin-tested with another insulin preparation before its initiation. Desensitization procedures may permit resumption of insulin administration. 

In a cross-sectional study in Sweden the frequencies of skin test reactivity to the atypical mycobacteria M. avium and M. scofulaceum were higher rather than lower in allergic compared to non-allergic children. There was a tendency toward a lower frequency of more strongly positive skin reactions to mycobacteria in allergic rather than non-allergic children. These results do not support the hypothesis that early mycobacterial infections have a suppressive effect on the development of atopic disease [157(111)]. 

ADVERSE REACTIONS Hypersensitivity reactions are the most common side effects of cephalosporins they are identical to those caused by the penicillins, perhaps related to their shared /3-lactam structure. Patients who are allergic to one drug class may manifest cross-reactivity to a member of the other class. There is no skin test that can reliably predict whether a patient will manifest an allergic reaction to the cephalosporins. 

Assem ESK, Vickers MR (1974) Tests for penicillin allergy in man. II. The immunological cross-reaction between penicillins and cephalosporins. Immunology 27 255 Assem ESK, Vickers MR (1975) Investigation of the response to some haptenic determinants in penicillin allergy by skin and in vitro allergy tests. Clin Allergy 5 43... 

Chakravarty S, Sircar DK (1961) Allergic reactions due to streptomycin corroboration of clinical findings with streptomycin skin tests. Acta Tuberc Scand 41 144-148 Chung CW, Carson TR (1976) Cross-sensitivity in common aminoglycoside antibiotics. Arch Dermatol 112 1101-1107... 

Immunologic A 46-year-old woman had an IgE-mediated hypersensitivity reaction to transdermal fentanyl and developed generalized erythema and bronchospasm 4 hours after the application of transdermal fentanyl. In preparation for another surgical procedure, skin tests were carried out [90 ]. A prick test for fentanyl was negative, but an intradermal test was positive. There was also cross-reactivity to sufentanil. The delay in response between application and the onset of symptoms was believed to be due to the cutaneous route of administration. 

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