Alergia a beta-lactâmicos na clínica pediátrica: uma abordagem prática

Abstract

Objective: To present a practical approach to the diagnosis and management of allergy to beta-lactam antibiotics.Sources: Allergy journals indexed in MEDLINE and LILACS, as well as seminal studies and texts.Summary of the findings: Allergy to penicillin is commonly reported. In many cases, this results in the decision not to use this drug. About 10% of drug allergy reports are confirmed. The clinical manifestations due to allergic reaction to penicillin vary widely, with emphasis on skin disorders. Gell & Coombs four hypersensitivity mechanisms are involved in allergic reactions. Penicillin is degraded to a major (95%) and minor determinants (5%). Immediate IgE-mediated reactions causing anaphylaxis are associated with minor determinants in 95% of the cases. Hypersensitivity to these products can be assessed using cutaneous tests performed with major and minor determinants, thus avoiding anaphylactic shock in allergic individuals. The present article underscores the basic body of knowledge on allergy to penicillin, providing support for a more accurate diagnosis of this event and for the choice of management in cases of suspected beta-lactam allergy. Conclusions:The incorrect diagnosis of penicillin allergy frequently leads to the exclusion of this drug as a therapeutic option. A better recognition of these situations will enable the use of penicillin and reduce the risks associated with hypersensitivity.J Pediatr (Rio J). 2006;82(5 Suppl):S181-8: Beta-lactam, penicillin, cephalosporin, allergy, hypersensitivity reaction. REVIEW ARTICLE

Hipersensibilidade aos β-lactâmicos e outros antibióticos. Bases biológicas

“…A elevada alta reatividade cruzada in vitro entre penicilinas e cefalosporinas não é a observada "in vivo" 29 . Assim, quando há a necessidade de administrar cefalosporinas a um paciente com histórico de hipersensibilidade às penicilinas, é preciso realizar, previamente testes cutâneos, e o tratamento pode ser iniciado, caso o resultado seja negativo, pois indica que o paciente é reativo apenas à cadeia lateral do antibiótico 30 . Uma exceção a essa reatividade são o monobactâmicos, como o aztreonam, que, pela ausência do núcleo bicíclico, não apresentam reatividade com penicilina e são opção terapêutica para esses casos 4,29 .…”

“…Existem vários protocolos com esse objetivo, que defendem a administração soluções contento o alérgeno em concentrações diminutas, mas crescentes, produzindo aquilo que Legendre et al 36 (2014) descreveram como uma "anafilaxia controlada", onde mastócitos ligados à IgE degranularão em concentrações modestas do alérgeno e não darão uma resposta sistêmica. Na medida em que as dosagens do fármaco forem sendo duplicadas, o que geralmente é feito a cada 15 minutos, obsrva-se a supressão dos receptores de IgE na superfície da mastócitos e quando isso ocorre, a dose clínica necessária da droga poderá ser utilizada 30,36 . É importante enfatizar que essa modalidade de dessensibilização perdura por um período de 24-36 horas, nas quais os mastócitos não mais degranulam em função da supressão induzida, mas o paciente permanece com as bases imunológicas de sua hipersensibilidade ao antimicrobiano e poderá ter uma reação intensa à droga fora desse período de segurança 10 .…”

Employing molecularly imprinted polymers in the development of electroanalytical methodologies for antibiotic determination

“…The β‐lactam group was the first class of antimicrobial natural products introduced in the therapeutic treatment of bacterial infections, this group has represented about 50% of all antibiotics prescribed in 2004 138,140,141 . MIPs were described to the quantification of amoxicillin in pharmaceuticals, milk and honey [93], 110 ampicillin in water, buffer, milk, animal feed and egg, 54,111,112 cefalexin in samples of river water and pharmaceuticals, 75 cefixime in samples of human serum and urine, 44,68 cefotaxime in samples of human serum, 79 cefquinome in buffer, 94 ceftazidime in samples of human serum, 113 cloxacillin in milk 123 and oxacillin in milk 71 …”

Identification of new minor metabolites of penicillin G in human serum by multiple‐stage tandem mass spectrometry

“…The chemical structures of PCNs are similar and the distinction among the analogs is based on the nature of the side‐chain group. Penicillin G (benzylpenicillin or PCN G) was the first antibiotic found by man and is widely applied for human bacterial disease; furthermore, PCN G has been considered as the model compound for the study of allergy to β‐lactam 4, 5…”

“…Penicillin G (benzylpenicillin or PCN G) was the first antibiotic found by man and is widely applied for human bacterial disease; furthermore, PCN G has been considered as the model compound for the study of allergy to b-lactam. [4,5] Allergic drug reactions have been considered to be a serious problem for the diagnosis or treatment of any medical condition. [6] The allergic reactions do not result from known toxicological properties of the drug, but from immune reactions to the parent drug or to its metabolites.…”