ABSTRACT
OBJETIVO: Apresentar uma abordagem prática ao diagnóstico e conduta na alergia a antibióticos beta-lactâmicos. FONTES DOS DADOS: Periódicos da área de alergia indexados nas bases MEDLINE e LILACS, além de estudos e textos clássicos que tratam do tema. SíNTESE DOS DADOS: A alergia à penicilina é relatada com freqüência, em muitos casos resultando na exclusão desse medicamento do arsenal terapêutico. Cerca de 10 por cento dos relatos de alergia a drogas são confirmados. As manifestações clínicas decorrentes da reação alérgica à penicilina são bastante amplas, destacando-se os quadros cutâneos. Os quatro mecanismos de hipersensibilidade de Gell & Coombs estão envolvidos nas reações alérgicas. A penicilina é degradada em determinante maior (95 por cento dos produtos) e em determinantes menores (5 por cento dos produtos). As reações imediatas, mediadas por IgE, e que determinam quadros de anafilaxia, estão relacionadas aos determinantes menores em 95 por cento dos casos. A hipersensibilidade a esses produtos pode ser avaliada através de testes cutâneos realizados com os determinantes maior e menores, permitindo, assim, evitar o choque anafilático em indivíduos alérgicos. O texto ressalta conhecimentos básicos sobre a alergia à penicilina, propiciando um diagnóstico mais adequado desse evento e a conduta em casos de suspeita de alergia a beta-lactâmicos. CONCLUSÃO: O diagnóstico de alergia à penicilina tem sido feito de forma inadequada, resultando em sua exclusão do arsenal terapêutico. O melhor reconhecimento dessas condições permitirá o uso da penicilina com diminuição dos riscos decorrentes da hipersensibilidade.
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 percent 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 percent) and minor determinants (5 percent). Immediate IgE-mediated reactions causing anaphylaxis are associated with minor determinants in 95 percent 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.
Subject(s)
Humans , Child , Anti-Bacterial Agents/adverse effects , Cephalosporins/adverse effects , Drug Hypersensitivity/diagnosis , Hypersensitivity, Immediate/chemically induced , Penicillins/adverse effects , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/immunology , Cephalosporins/chemistry , Cephalosporins/immunology , Penicillins/chemistry , Penicillins/immunology , Sensitivity and Specificity , Skin Tests , Time FactorsABSTRACT
Bactericidal activity of ceftazidime is determined by the time that concentrations in tissue and serum are above the MIC for the pathogens during the dosing interval. Thus, the most effective mode of administration of ceftazidime is continuous infusion. However, this agent is light sensitive which may result in instability when administered by this method without protection from light. Until now we have had no data to demonstrate the stability of this drug during continuous infusion. Therefore, the objective of this study was to provide such data. One gram of ceftazidime was mixed with 1,000 ml normal saline and exposed to two 36 watt fluorescence lights for 24 hours. The distance between ceftazidime solution and light source was 1 meter. Twenty samples (1 g-ceftazidime in normal saline) solution were evaluated. The mean ceftazidime concentrations in normal saline solution were decreased by only 1.69%, 4.44% and 7.19% after 6, 12 and 24 hours after exposure to light, respectively. Therefore, we conclude that the reduction of drug concentration was not considered to be significantly high, and this agent can be administered by continuous infusion.
Subject(s)
Ceftazidime/chemistry , Cephalosporins/chemistry , Drug Stability , Light , Sodium Chloride , SolutionsABSTRACT
Las cefalosporinas son uno de los grupos de mayor importancia dentro de los ß-lactámicos. Existen diversas clasificaciones de esta moléculas, siendo la más utilizada aquella que agrupa a estos compuesto de acuerdo a propiedades estructurales, microbiológicas y desarrollo histórico: primera a cuarta generación. Las cefalosporinas de tercera generación han sido ampliamente utilizadas, pero la emergencia de resistencia bacteriana fundamentalmente derivada de la producción de ß-lactamasas tanto cromosomales como plasmidiales, ha limitado el uso de estos compuestos. Las cefalosporinas de cuarta generación se caracterizan por la presencia de un nitrógeno cuaternario en C, además de mantener el grupo metoxi-imino aminotiazolil en C. Presentan una elevada penetración intracelular a través de la membrana externa de bacilos Gram negativos y tienen una baja afinidad por enzimas que degradan cefalosporinas de tercera generación. Cefepime, una cefalosporina de cuarta generación, demostró una mayor actividad inhibitoria sobre cepas chilenas de Klebsiella pneumoniae y Escherichia coli productoras de ß- lactamasa de espectro extendido, que cefotaxima y ceftazidima
Subject(s)
Humans , Cephalosporins/pharmacology , Communicable Diseases/drug therapy , Cefotaxime/pharmacology , Ceftazidime/pharmacology , Cephalosporin Resistance , Cephalosporins/chemistry , Cephalosporins/classification , Drug Resistance, Microbial , Lactams/pharmacologyABSTRACT
El cefepime es un antibiótico útil para el tratamiento de diferentes enfermedades. En el presente artículo se describe el efecto de esta cefalosporina, que se caracterizó en pacientes con infecciones de vías respiratorias y urinarias, bacteriemia, septicemia y neutropenia febril. También se detallan aspectos sobre su actividad en casos de infecciones intraabdominales, ginecológicas y de la piel. En estos estudios se identificó que el cefepime produjo las mejores respuestas clínicas, en comparación con cefalosporinas de tercera generación. Por ello, el cefepime representa una alternativa terapéutica muy útil para controlar infecciones adquiridas en la comunidad o nosocomiales
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Cephalosporins/chemistry , Cephalosporins/pharmacology , Statistics/methods , Neutropenia/therapy , Respiratory Tract Infections/therapy , Sepsis/therapy , Urinary Tract Infections/therapyABSTRACT
Among different matrices prepared, ampicilloic acid-polymer matrix offered 86.7% adsorption, 95% elution and 82.4% overall recovery of penicillinase. The structure of both the side chain and penicilloic or cephalosporoic acid moieties contribute to the affinity interactions.
Subject(s)
Adsorption , Bacillus cereus/enzymology , Cephalosporins/chemistry , Chromatography, Affinity/methods , Fermentation , Ligands , Penicillanic Acid/analogs & derivatives , Penicillinase/analysisABSTRACT
Las cefalosporinas orales son antibióticos beta lactámicos de amplio espectro, frecuentemente usados en el tratamiento de infecciones de la comunidad en forma empírica o previa comprobación microbiológica, tanto en las debidas a gérmenes gram positivos como negaticos. Diferen entre ellas respecto a su espectro y potencia antimicrobiana, resistencia bacteriana, farmacocinética y costo. En general las cefalosporinas de 1 ra. generación son más activas sobre los gram positivos, tienen menos resistencia a las beta lactamasas de los negativos, menor t 1/2 y menor costo. Las de 2da. generación amplían su espectro, por aumento de resistencia a las beta lactamasas y presentan vida media más larga. Los agentes de 3ra. generación son los más activos frente a enterobacterias, tienen alta resistencia a las beta lactamasas, propiedades farmacocinéticas mejoradas que permiten una o dos administraciones diárias y mayor costo. La habilidad en la elección y uso de las cefalosporinas, continúa siendo un desafío para el médico clínico, ya que el desarrollo de nuevas cefalosporinas continúa (impulsado por el avance de la resistencia bacteriana que ha afectado todos los pasos del mecanismo íntimo de acción de estas drogas) y que en un futuro cercano serán introducidas nuevas cefalosporinas en el mercado
Subject(s)
Humans , Cephalosporins/pharmacology , Administration, Oral , Gram-Negative Bacteria , Gram-Positive Bacteria , Cephalosporins/chemistry , Cephalosporins/economics , Cephalosporins/therapeutic use , Gram-Negative Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/drug therapy , Drug Resistance, MicrobialABSTRACT
The Schiff's base formation between 6-aminopenicillanic acid, 7-aminodesacetoxycephalosporanic acid and 7-aminocephalosporanic acid and p-dimethylaminobenzaldehyde (PDAB) was investigated. The factors that affect the reaction such as concentration of PDAB, time and pH were studied and optimised for estimation of these intermediates.
Subject(s)
Benzaldehydes/chemistry , Calibration , Cephalosporins/chemistry , Hydrogen-Ion Concentration , Indicators and Reagents/chemistry , Kinetics , Penicillanic Acid/analogs & derivatives , Schiff Bases/chemistrySubject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacokinetics , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/therapeutic use , Pediatrics , Aminoglycosides/administration & dosage , Aminoglycosides/pharmacokinetics , Aminoglycosides/toxicity , Aminoglycosides/therapeutic use , Anti-Bacterial Agents/toxicity , Cephalosporins/chemistry , Cephalosporins/classification , Cephalosporins/toxicity , Clindamycin/pharmacology , Clindamycin/supply & distribution , Clindamycin/toxicity , Penicillins/administration & dosage , Penicillins/adverse effects , Penicillins/chemistry , Penicillins/classificationABSTRACT
Mostra a química, a farmacologia, a eficácia clínica, o perfil de segurança, a dosagem e administração e a ação sobre o "Haemophilus Influenzae" do antibiótico Faclor