Penicillins allergy minor” determinants

Patients with a history of penicillin allergy should undergo skin testing with both peniciUoyl-polylysine and minor determinant mixtures. Patients with positive skin tests should be treated with another immunologically unrelated compound or should undergo desensitization. The management of patients with a negative skin test but a history of a severe IgE-mediated reaction has to be individualized options include the use of an alternative compound, desensitization, or the controlled administration of a test dose. 

In addition to the penicilloyl determinant several other antigenic determinants are involved in penicillin allergy, the so-called minor antigenic determinants. Although much work has been carried out to establish the chemical structure of these determinants and the pathways to their formation (as reviewed by Schwartz 1969 Dewdney 1977) no firm conclusions have been reached as yet. 

Gorevic PD, Levine BB (1981) Desensitization of anaphylactic hypersensitivity specific for the penicilloate minor determinant of penicillin and carbenicillin. J Allergy din Immunol 68 267... 

Benzylpenicilloic acid is the main hydrolysis product of benzylpenicillin and is able to elicit wheal and flare reactions when used in skin tests in some patients allergic to penicillins. It has therefore been considered as one of the minor antigenic determinants of penicillin allergy (Siegel and Levine 1964 Voss et al. 1966) although the precise chemical nature of the determinant(s) derived from penicilloic acid has not been elucidated. The proportion of patients responding in skin test to penicilloic acid varies between 21% and 55% (Table 1). 

Romano A, Gaeta F, Valluzzi RL, Caruso C, Rumi G, Bousquet PJ. The very limited usefulness of skin testing with penicilloyl-polylysine and the minor determinant mixture in evaluating nonimmediate reactions to penicillins. Allergy 2010 65(9) 1104-7. 

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