Cross-reactivity penicillins

The cephalosporins generally cause few side effects (80,132,219—221). Thrombophlebitis occurs as a result of intravenous administration of all cephalosporins. Hypersensitivity reactions related to the cephalosporins are the most common side effects observed, but these are less common than found with the penicillins. Clinically only about 5—10% of patients with allergic reactions to the penicillins manifest the same reactions to the cephalosporins, and data would contradict any tme cross-reactivity to cephalosporins in patients who have previously reacted to penicillin (80,132,219). 

For other (3-lactam agents, the recommendations are fairly straightforward.9 Carbapenems should be considered cross-reactive with penicillins. Monobactams (e.g., aztreonam) do not cross-react with any (3-lactam drugs except ceftazidime because they share an identical R-group side chain. 

Minimal cross-reactivity between aztreonam and penicillins and cephalosporins aztreonam and aminoglycosides have been shown to be synergistic in vitro against most strains of P. aeruginosa, many strains of Enterobacteriaceae, and other gramnegative aerobic bacilli... 

The amount of label bound to the MIP in the absence of the analyte is known as B0 and B is the amount of label bound to the MIP in the presence of each concentration of analyte. The plot of the ratio B/B0 as a function of the log[analyte], or the log [interferent], is a sigmoid curve such as the one shown in Fig. 7 for the penicillin G assay described above. As the concentration of penicillin G increases in the sample, the amount of bound PAAP decreases as does the B/B0 ratio. Another p-lactam antibiotic not derived from penicillin, such as cephapirin, did not show any cross-reactivity (Fig. 7). 

The generic nature of the antiserum was shown by good relative cross-reactivities with penicillin type (3-lactam antibiotics such as amoxicillin (50%), ampicillin (47%), and penicillin V (145%), and a lower response to the isoxazolyl penicillins such as oxacillin, cloxacillin, and dicloxacillin. No cross-reactivity was obtained for cephalosporin type p-lactam antibiotics (cephapirin), cloramphenicol, or fluoroquinolones (enrofloxacin and ciprofloxacin). 

It has also been reported that patients with allergic-like events after penicillin treatment have had a markedly risk of events after subsequent cephalosporin antibiotics. Cross-reactivity is not an adequate explanation for this increased risk and the data obtained indicate that cephalosporins can be considered for patients with penicillin allergy <2006MI354.ell>. Comparisons of parenteral broad-spectrum cephalosporins have been tested against bacteria isolated from pediatric patients. The results have indicated that cefepime has been the most broad-spectrum cephalosporin analyzed and it is a very potent alternative for the treatment of contemporary pediatric infections in North America <2007MI109>. The historical safety of the most commonly used oral cephalosporins has been reviewed <2007MIS67>. The antimicrobial spectrum and in vitro potency of the most frequently prescribed orally administered cephalosporins (cefaclor, cefdinir, cefpodoxime, cefprozil, cefuroxime axetil and cephalexin has also been reviewed <2007MIS5>. 

Adverse effects Aztreonam is relatively nontoxic, but it may cause phlebitis, skin rash, and occasionally, abnormal liver function tests. Aztreonam has a low immunogenic potential and shows little cross-reactivity with antibodies induced by other p-lac-tams. Thus aztreonam may offer a safe alternative for treating patients allergic to penicillins and/or cephalosporins. 

Ceftriaxone is a cephalosporin antibiotic. Consider using a different antibiotic if the person has a true penicillin allergy, as cephalosporins show cross-reactivity to penicillins in about 8% of people. 

As with the penicillins, hypersensitivity reactions are the most common systemic adverse events caused by cephalosporins. Maculopapular rash, urticaria, fever, bron-chospasm,and anaphylaxis have been associated with the use of cephalosporins.Because the molecular structure of the penicillins and the first-generation cephalosporins are similar, there is a risk in patients who are aUergic to penicillin to manifest aUergic cross-reactions when prescribed any of this gronp of cephalosporins. In contrast, the risk of cross-reactivity between the penicUUns and the second-, third-, and fonrth-generation cephalosporins has been overestimated, and patients with a previons aUergic... 

There is cross-allergy between all the various forms of penicillin, probably due in part to their common structure, and in part to the degradation products common to them all. Partial cross-allergy exists between penicillins and cephalosporins (a maximum of 10%) which is of particular concern when the reaction to either group of antimicrobials has been angioedema or anaphylactic shock. Carba-penems (meropenem and imipenem-cilastatin) and the monobactam aztreonam apparently have a much lower risk of cross-reactivity. 

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. 

Saxon A, Adelman DC, Patel A, Hajdu R, Calandra GB. Imipenem cross-reactivity with penicillin in humans. J Allergy Clin Immunol 1988 82(2) 213-17. 

The patient s serum was tested for antibodies against five penicillins and 30 different cephems (that is all types of cephalosporins), using protocols to detect drug adsorption as well as immune-complex mechanisms. His serum contained an IgM antibody that formed immune complexes with 10 of the 30 cephems. The 10 drugs were classified as oxime-type cephalosporins, that is they had a common structural formula at the C7 position on 7-aminocephalosporinic acid. This antibody did not show any cross-reactivity with five kinds of penicillins (ampiciUin, aspoxicillin, carbenicil-lin, piperacillin, sulbeniciUin). The authors asked a difficult question Why did anaphylactic shock accompany acute hemolysis Their answer was that the complex of ceftizoxime with IgM anti-ceftizoxime might act like anti-A or anti-B. This hypothesis will surely be further tested. In the meantime, it would be wise not to use the newer cephalosporins too freely. 

Blanca M, Fernandez J, Miranda A, Terrados S, Torres MJ, Vega JM, Avila MJ, Perez E, Garcia JJ, Suau R. Cross-reactivity between penicillins and cephalosporins clinical and immnnologic stndies. J Allergy Clin Immunol 1989 83(2 Pt l) 381-5. 

Negligible cross-reactivity has been reported in both animal and human studies involving hapten inhibition, skin tests, and treatment of penicillin-allergic patients with therapeutic doses of aztreonam (12,14-19). Aztreonam therefore seems to be a safe alternative for patients with penicillin allergy. However, the numbers of safely treated patients reported are still small, and immediate type hypersensitivity to aztreonam has been reported in patients with penicillin allergy (20-23). 

Moss RB, McClelland E, Williams RR, Hilman BC, Rubio T, Adkinson NF. Evaluation of the immunologic cross-reactivity of aztreonam in patients with cystic fibrosis who are allergic to penicillin and/or cephalosporin antibiotics. Rev Infect Dis 1991 13(Suppl 7) S598-607. 

Sastre J, Quijano LD, Novalbos A, Hernandez G, Cuesta J, de las Heras M, Lluch M, Fernandez M. ainical cross-reactivity between amoxicillin and cepha-droxil in patients allergic to amoxicillin and with good tolerance of penicillin. Allergy 1996 51(6) 383-6. 

Hypersensitity reaction in patients with hypersensitivity reactions to penicillins, the incidence of cross-reactivity to carbapenems is 50%. 

Cross-reactivity between pencillins and cephalosporins ranges from 5% to 10%. Even though some patients with a history of penicillin allergy may tolerate cephalosporins, patients with a history of anaphylaxis to penicillin should not receive cephalosporins. 

E Because JK has experienced anaphylaxis to amoxicillin, prescription of any type of penicillin or cephalosporin should be avoided. Cross-reactivity between penicillins and cephalosporins is incomplete, but with a history of anaphylaxis to penicillins, cephalosporins should not be prescribed. Clindamycin would be an appropriate alternative to use to treat the cellulitis. 

Other /3-lactam derivatives (e.g., monobactams and carbapen-ems) have been studied for potential cross-reactivity with peniciUms. In vitro and in vivo studies have demonstrated that aztreonam only weakly cross-reacts with penicillin and that it may be administered safely to most patients who are peniciUin-allergic. In contrast, there is considerable cross-reactivity between imipenem (a carbapenem) and penicillin. Therefore, imipenem (and other carbapenems) should not be administered to patients who have positive penicillin skin tests. 

Describe the cross-reactivity between penicillins and cephalosporins. 

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. 

Allergy Cephalosporins cause a range of allergic reactions from skin rashes to anaphylactic shock. These reactions occur less frequently with cephalosporins than with penicillins. Complete cross-hypersensitivity between different cephalosporins should be assumed. Cross-reactivity between penicillins and cephalosporins is incomplete (5-10%), so penicillin-allergic patients are sometimes treated successfully with a cephalosporin. However, patients with a history of anaphylaxis to penicillins should not be treated with a cephalosporin. 

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