Cross-allergy penicillin

Some types of allergic reaction, for example immediate or delayed-type skin allergies, serum-sickness-like reactions and anaphylactic reactions, may occur in a proportion of patients given penicillin treatment. There is some, but not complete, cross-allergy with cephalosporins. 

Because penicillins and cephalosporins have a common chemical structure, cross-allergies occur with these drugs. Thus before initiating therapy with a penicillin. 

The cephalosporins are contraindicated in patients with known allergies or intolerances to any of the cephalosporins. Because the penicillins and cephalosporins have a common chemical structure, cross-allergies occur with these drugs. Thus before initiating therapy with a cephalosporin, careful inquiry should be made concerning previous hypersensitivity reactions to the other drugs. Because a secondary vitamin K deficiency can develop with cephalosporin use, the cephalosporins are contraindicated in patients with hemophilia. Cefaclor is also contraindicated in any patient with previous drug-related joint and skin reactions. 

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. 

Hypersensitivity reactions are frequent early in a course of penicillamine, with urticarial or maculopapular rashes, fever, and lymphadenopathy. Cross-allergy to penicillin can occur. In addition, the use of penicillamine can be complicated by a unique variety of often serious autoimmune reactions, involving the skin, kidneys, liver, lungs, muscles, or other organs. Proteinuria is found in more than 10% of patients and sometimes develops into the nephrotic syndrome. Pemphigus, myasthenia gravis, polymyositis, or a lupus-like syndrome occur in smaller percentages. 

Immune cross-reactivity of benzylpenicillin and ceph-alothin was reported.23 cross-allergenicity to penicillins and cephalorsporins was noted.23 in contrast, in a study on the allergenicity and toxicity of cephaloridlne and ceph-alothin, no cross-allergy with the penicillins was observed.27 An orally effective cephalosporin, e.. cephalexin, as well as oral penicillins, would appear to have greatly less sensitizing potential than those given by injection. 

Because of cross-reactions between cephalosporins and penicillins, caution should be used when prescribing cephalosporins to patients with penicillin allergy. If a patient had anaphylaxis, angioedema, or urticaria fol-... 

Imipenem-cilastatin is one of the drugs of first choice for the empirical therapy of many polymicrobial pulmonary, intraabdominal, and soft tissue infections. The notable adverse effect of imipenem-cilastatin is seizures affecting 1% of patients. Risk factors for seizures are old age, head trauma, previous seizure disorder, cerebrovascular accident, and renal failure. Among patients with a history of penicillin allergy, 10% are cross-sensitive to imipenem-cilastatin. 

Cephalosporins are sensitizing and may elicit a variety of hypersensitivity reactions that are identical to those of penicillins, including anaphylaxis, fever, skin rashes, nephritis, granulocytopenia, and hemolytic anemia. However, the chemical nucleus of cephalosporins is sufficiently different from that of penicillins so that some individuals with a history of penicillin allergy may tolerate cephalosporins. The frequency of cross-allergenicity between the two groups of drugs is uncertain but is probably around 5-10%. However, patients with a history of anaphylaxis to penicillins should not receive cephalosporins. 

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>. 

Allergic manifestations The cephalosporins should be avoided or used with caution in individuals allergic to penicillins (about 5 to 15% show cross-sensitivity). In contrast, the incidence of allergic reactions to cephalosporins is 1-2% in patients without a history of allergy to penicillins. 

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. 

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. 

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). 

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. 

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. 

Once an individual is alleigjic to one penicillin, he or she is most likely allergic to all of the penicillins. Those alleigic to penicillin also have a higher incidence of allei to the cephalosporins (see Ch ). 8). Allergy to dni in the same or related groups is called cross-sensitivity or cross-allergenicity. 

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. 

First-generation cephalosporin prototype bactericidal beta-lactam inhibitor of cell wall synthesis. Active against gram-positive cocci, E coli, K pneumoniae. but does not enter CSF. Tox potential allergy partial cross-reactivity with penicillins. 

Antibiotic carbapenem active against many aerobic and anaerobic bacteria, including penicillinase-producing organisms a bactericidal inhibitor of cell wall synthesis. Used with cilastatin (which inhibits metabolism by renal dehydropeptidases). Tox allergy (partial cross-reactivity with penicillins), seizures (overdose). Meropenem is similar but does not require cilastatin. 

Allergenicity is less commonly experienced and is less severe with cephalosporins than with penicillins. Cephalosporins frequently are administered to patients who have had a mild or delayed penicillin reaction. Cross-allergenicity is comparatively common, however, and cephalosporins should be administered with caution for patients who have a history of allergies. Patients who have had a rapid and severe reaction to penicillins should not be treated with cephalosporins. 

Antimicrobial medication requires the nurse to follow the same general administration procedures that are required for any type of medication. The most critical step is to determine if the patient has allergies to drugs, food, environmental stimuM, and a family history of allergies to antibiotics. There is also a high incidence of cross sensitivity between some antibiotics such as penicillin and cephalasporins. Always display allergies in red and clearly write them on the patient s record. Even if the patient s record indicates that the patient doesn t have allergies, always ask the patient each time you administer the antimicrobial medication. 

Hjorth N (1958) Contact dermatitis from vitamin B (thiamine). Relapse after ingestion of thiamine. Cross sensitization to cocarboxylase. J Invest Dermatol 30 261-264 Hjorth N (1961) Eczematous allergy to balsams. Acta Derm Venereol [Suppl] (Stockh) 41 46 Hjorth N (1967) Occupational dermatitis among veterinary surgeons caused by penetha-mate (benzyl-penicillin-B-diethyl-aminoethyl ester). Berufsdermatosen 15 163-175 Hjorth N (1972) Contact dermatitis from l,3-diiodo-2-hydroxypropane. Contact Dermatitis Newslett 12 322... 

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