Juan José García

Cross-reactivity between a penicillin and a cephalosporin with the same side chain ☆ ☆☆ ★ ★★

BACKGROUND The cross-reactivity between penicillins and cephalosporins can be influenced by different factors, which are not all well known. The chemical structure of the side chain may contribute to the cross-reactivity. OBJECTIVE The study was carried out in allergic subjects who are selectively responsive to amoxicillin to determine allergenic cross-reactivity with a cephalosporin containing a side chain identical to that of amoxicillin, cefadroxil, and one containing a different side chain, cefamandole. METHODS Allergic subjects with a selective response to amoxicillin were chosen according to the following criteria: history of an immediate allergic reaction to amoxicillin, negative skin test responses to benzylpenicilloyl and minor determinant mixture of benzylpenicillin, negative RAST response to benzylpenicilloyl, and good tolerance to benzylpenicillin and phenoxymethyl penicillin challenges. In addition, subjects had to have a positive skin test response to amoxicillin and/or positive RAST response to amoxicilloyl or, if these test results were negative, a positive challenge test response to amoxicillin. In vivo cross-reactivity to cefadroxil was assessed by giving oral cefadroxil at increasing doses from 5 to 500 mg. In vitro cross-reactivity was determined by RAST inhibition studies with amoxicilloyl RAST disks and the following monomeric conjugates in the fluid phase: amoxicillin-butylamine, cefadroxil-butylamine, and the side chain para-hydroxy-phenylglycine. Tolerance to cefamandole was determined by giving 100 mg and then 500 mg parenterally. RESULTS Twenty-one patients with a selective response to amoxicillin were included in the study. Eight subjects (38%) had a positive response to cefadroxil, and none reacted to cefamandole. In vitro RAST inhibition studies indicated that cefadroxil-butylamine monomers cross-reacted with amoxicillin butylamine and the side chain contributed relevantly to the inhibition. CONCLUSIONS These results indicate that the percentage of cross-reactivity between penicillins and cephalosporins with an identical side chain is high and that this critical part of the molecule seems to be an important contributor to these results. The value is higher than previously reported data from similar studies of non-side-chain-related cephalosporins.

Cross-reactivity between penicillins and cephalosporins: clinical and immunologic studies.

Nineteen well-characterized penicillin-allergic patients were investigated for their sensitivity to cephalosporins containing potentially cross-reactive side chains. All patients were administered cephamandole parenterally and, if this was tolerated, a course of oral cephaloridine was administered. Only two patients responded to the cephamandole; none of the remaining patients reacted to cephaloridine. Benzylpenicilloyl RAST-inhibition studies with sera from three subjects who had not reacted to the cephalosporins demonstrated that cephamandole linked to proteins was capable of recognizing benzylpenicilloyl-specific IgE antibody. It is concluded that consideration of side chain structures can help to predict possible cross-reactions between penicillins and cephalosporins, but carefully controlled challenge tests are advisable before penicillin-allergic patients are treated with cephalosporins. In relation to cross-reacting potential, in vitro experimental studies are difficult to interpret and may in some circumstances overestimate the risk.

Determination of IgE antibodies to the benzylpenicilloyl determinant: a comparison of the sensitivity and specificity of three radio allergo sorbent test methods.

The quantitation of in vitro IgE antibodies to the benzylpenicilloyl determinant (BPO) is a useful tool for evaluating suspected penicillin allergic subjects. Although many different methods have been employed, few studies have compared their diagnostic specificity and sensitivity. In this study, the sensitivity and specificity of three different radio allergo sorbent test (RAST) methods for quantitating specific IgE antibodies to the BPO determinant were compared. Thirty positive control sera (serum samples from penicillin allergic subjects with a positive clinical history and a positive penicillin skin test) and 30 negative control sera (sera from subjects with no history of penicillin allergy and negative skin tests) were tested for BPO‐specific IgE antibodies by RAST using three different conjugates coupled to the solid phase: benzylpenicillin conjugated to polylysine (BPO‐PLL), benzylpenicillin conjugated to human serum albumin (BPO‐HSA), and benzylpenicillin conjugated to an aminospacer (BPO‐SP). Receiver operator control curves (ROC analysis) were carried out by determining different cut‐off points between positive and negative values. Contingence tables were constructed and sensitivity, specificity, negative predictive values (PV–), and positive predictive values (PV+) were calculated. Pearson correlation coefficients (r) and intraclass correlation coefficients (ICC) were determined and the differences between methods were compared by χ2 analysis. Analysis of the areas defined by the ROC curves showed statistical differences among the three methods. When cut‐off points for optimal sensitivity and specificity were chosen, the BPO‐HSA assay was less sensitive and less specific and had a lower PV– and PV+ than the BPO‐PLL and BPO‐SP assays. Assessment of r and ICC indicated that the correlation was very high, but the concordance between the PLL and SP methods was higher than between the PLL and HSA or SP and HSA methods. We conclude that for quantitating IgE antibodies by RAST to the BPO determinant, BPO‐SP or BPO‐PLL conjugates offer advantages in sensitivity and specificity compared with BPO‐HSA. These results support and extend previous in vitro studies by our group and highlight the importance of the carrier for RAST assays. J. Clin. Lab. Anal. 11:251–257, 1997.

Intolerance to piroxicam in patients with adverse reactions to nonsteroidal antiinflammatory drugs

To evaluate the tolerance to piroxicam in patients with urticaria induced by analgesic and/or nonsteroidal antiinflammatory drugs (NSAIDs), we carried out a 2-year study in an outpatient clinic. All the patients referred to the clinic for study entered a protocol for evaluation of intolerance to one or more drugs. If patients were allergic to at least two different NSAIDs they were allocated to group A, but if patients were allergic to only one they were considered as having selective intolerance (group B). Either piroxicam or placebo was administered under controlled conditions to both groups. In group A, five out of 18 patients had a positive response to piroxicam. In group B, in all the 25 cases studied a good tolerance to piroxicam was shown. These results indicate that in the group with intolerance to NSAIDs piroxicam induced a positive reaction in 27% of the cases, and that this drug should be administered with caution and with a previous controlled challenge in this type of patient. Piroxicam was well tolerated in the group with selective intolerance, indicating that mechanisms other than interference with the prostaglandin synthesis and release of inflammatory mediators participate in allergic reactions to NSAIDs.

Fixed drug eruption induced by mepivacaine

Less than 1% of adverse reactions to local anesthetics are allergic in nature? In particular, two types of immunologically mediated reactions to local anesthetics are commonly described: (1) IgE-mediated reactions (Gell and Coombs type I) and (2) allergic contact dermatitis (Gell and Coombs type IV). Although extremely rare, IgE-mediated reactions do occur in response to both amideand ester-group agents?, 3 They may be characterized by hives, angioedema, bronchospasm, rhinorrhea, or, in severe cases, by shock. Topical anesthetics are not only widely used but are also potent contact sensitizers. They produce more than 80% of the total allergic reactions to local anesthetics. 4 They are characterized by contact dermatitis. On the basis of limited patch testing data, it has been postulated that ester-group anesthetic agents cross-react with each other, but not with the amide-group agents. This postulate appears to hold true with regald to contact hypersensitivity but has never been adequately studied with regard to IgE-mediated hypersensitivity, s Fixed drug eruption is characterized by an isolated erythematous macular pruritic lesion. An acute phase is followed by desquamation and hyperpigmentation. The lesion usually appears in the oral or genital mucous membranes but occasionally arises on the face. With re-stimulation, lesions always appear in the same place. The agents usually involved are: phenolphthalein, tetracycline, sulfonamides, barbiturates, and nonsteroidal antiinflammatory drugs.

Competition of Thermal Electricity Generators with Coupled Transmission and Emission Constraints

AbstractThermal generators’ emissions constitute an externality on which a regulator might wish to impose constraints. In addition, transmission capacity for sending energy may be naturally restricted by the grid facilities. Both pollution standards and transmission capacity impose constraints, coupling the strategies of the agents in their joint strategy space. To force competitive electricity generators to respect those constraints when individual monitoring is unavailable we envisage the regulator solving a generalized Nash equilibrium problem to establish an equilibrium in which the joint constraints are satisfied. If the regulator appropriately modifies the generators’ payoffs then they will play a decoupled game in which they can ignore the information on the joint constraints. For the payoff modification to induce the required behavior, a coupled constraints equilibrium needs to exist and be unique. We borrow from the electrical engineering (EE) literature a three-node network model that has these ...

Impacto asistencial de la implantación de la vía clínica de septorrinoplastia

Resumen Las vias clinicas son instrumentos de mejora continua de la calidad asistencial, que conjugan la calidad cientifico-tecnica, la calidad gestora y la satisfaccion de los pacientes y profesionales para alcanzar los mejores resultados posibles mediante la medicina basada en la evidencia y la eficiencia en los procesos. Objetivos Analizar los resultados de la via de septorrinoplastia durante el primer ano de la implantacion y verificar la repercusion asistencial que ha supuesto su introduccion en el servicio de maxilofacial. Metodologia La evaluacion de los resultados de la via se ha obtenido de los documentos de la via y de la revision de historias clinicas. La valoracion del impacto de la via clinica se efectuo comparando los resultados de los pacientes intervenidos e incluidos en via con un grupo control formado por los pacientes intervenidos del mismo proceso durante el ano 1999, siendo ambos grupos comparables. Resultados De los 39 pacientes intervenidos durante el ano 2000 de septorrinoplastia en el servicio de maxilofacial 35 fueron incluidos en via (cobertura del 89,7%). La estancia media hospitalaria de los pacientes ingresados en via fue de 2,17 dias (DE: 0,62 dias), ajustandose a lo programado en via, frente a la estancia del grupo control de 2,41 dias (DE: 1, 24 dias). Las variaciones innecesarias debidas a los profesionales fueron un 20% en el grupo en via clinica frente al 84,8% en el grupo control (p La encuesta de satisfaccion con una cobertura del 60% (21/35) valoro la atencion recibida por el servicio con un indice de satisfaccion global (IS) del 98,3%. Conclusiones La via clinica de septorrinoplastia, primera via implantada en el Servicio de Maxilofacial, se revela como un instrumento innovador de la gestion clinica, que permite reducir de manera importante la variabilidad innecesaria, ajustar la estancia hospitalaria, aumentar la efectividad de la asistencia sin menoscabo de la calidad asistencial y conseguir una alta satisfaccion del paciente.

Evaluación de las reclamaciones presentadas en un servicio de urgencias pediátricas en un hospital materno-infantil

Resumen Fundamento El estudio de las reclamaciones realizadas por los usuarios en un Servicio de Urgencias, representa un parametro de calidad asistencial que nos permite valorar la satisfaccion del usuario y conocer los aspectos mejorables en el proceso de atencion al usuario. El objetivo es conocer la incidencia y analizar los motivos de las reclamaciones realizadas en un Servicio de Urgencias Pediatricas, asicomo su posible repercusion en la evolucion clinica del paciente. Metodos Estudio descriptivo y retrospectivo analizando las reclamaciones efectuadas en el Servicio de Urgencias Pediatricas de nuestro centro, entre enero-96 y julio-99. Para ello confeccionamos una hoja de recogida de datos y posteriormente revisamos las historias clinicas de los pacientes implicados. Resultados Se valoran un total de 61 reclamaciones, con una tasa anual media de 0,23/1000 urgencias pediatricas atendidas en urgencias. No hallamos diferencias entre el sexo de los pacientes, ni entre el parentesco de quien formula la queja. La forma de realizar la reclamacion fue como sigue: 72% escrita, 13% verbal, 15% telefonicamente. Con relacion a la distribucion de los dias de la semana, encontramos que el viernes con un 25% es el de mayor incidencia, seguido de lunes con el 20% y domingo con un 15%. El mes del ano con mayor numero de reclamaciones es febrero (18%), seguido de enero y junio (15%) y marzo (10%). Los motivos mas frecuentes de reclamacion fueron: demora excesiva en la atencion urgente (37%), insatisfaccion asistencial (30%), trato personal inadecuado (12%). La mayoria de reclamaciones se dirigieron hacia el estamento medico (89%), seguido del personal de enfermeria (5%). En ningun caso el motivo de reclamacion se ha relacionado directamente con la evolucion clinica del paciente y la mayoria de usuarios volvieron, por otros motivos, al servicio de urgencias. Conclusiones 1. La causa mas importante de reclamacion, y por tanto, de descontento del usuario es la demora asistencial, seguido de insatisfaccion asistencial. 2. En ningun caso, la demora asistencial ha supuesto cambio clinico en el paciente. 3. A pesar de la reclamacion del usuario, la mayoria, en caso necesario, acude nuevamente solicitando asistencia.

Hospitalizaciones infantiles asociadas a infección por virus de la gripe en 6 ciudades de España (2014-2016)

INTRODUCTION There are only a limited number of studies on the impact of influenza in the Spanish child population. The present work intends to increase this knowledge by studying some key aspects, such as the incidence of hospital admissions, clinic variables, comorbidities, and the vaccination status in the hospitalised children. METHODS A retrospective, observational study was conducted by reviewing the medical records of children under 15 years and hospitalised due to community acquired influenza confirmed microbiologically, during 2́flu seasons (2014-2015 and 2015-2016). The study was carried out in 10 hospitals of 6cities, which represent approximately 12% of the Spanish child population. RESULTS A total of 907 children were admitted to hospital with main diagnosis of influenza infection (447 <2 years), estimating an average annual rate of hospitalisation incidence of 0.51 cases / 1,000 children (95% CI; 0.48-0.55). Just under half (45%) of the cases had an underlying disease considered a risk factor for severe influenza, and most (74%) had not been vaccinated. The percentage of children with underlying diseases increased with age, from 26% in children <6 months to 74% in children >10 years. Admission to the PICU was required in 10% (92) of the cases, mainly due to acute respiratory failure. CONCLUSION Influenza continues to be an important cause of hospitalisation in the Spanish child population. Children <6 months of age and children with underlying diseases make up the majority (> 50%) of the cases. Many of the severe forms of childhood influenza that occur today could be avoided if current vaccination guidelines were met.

Bloodstream infection in patients receiving hematopoietic stem cell transplant. Seven years of experience with adults and children

BACKGROUND Bloodstream infection is a common complication, which can be life-threatening for hematopoietic stem cells transplant recipients. OBJECTIVE To analyze the characteristics of bloodstream infections in hematopoietic stem cell transplant recipients. MATERIALS AND METHODS Observational, retrospective study. We reviewed the records of 451 patients (autologous and allogeneic transplants) from January 2009 to October 2015. RESULTS 99 positive blood cultures in 73 patients with bloodstream infection (16%) were found. Mortality attributable to infectious causes was 17%. From the 99 bloodstream infection, 63% were caused by gram-negative bacilli (Escherichia coli 45%, Klebsiella spp 23%, Pseudomonas spp 11% Acinetobacter spp % and other bacilli 15%), 33% by gram-positive cocci, 3% by fungi and 1% by gram-positive bacilli. The gram-negative bacilli were ciprofloxacin resistant (81%), piperacillin/tazobactam resistant (48%), extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae (40%), cefepime resistant (39%) and there was no resistance noted to amikacin. DISCUSSION There is a higher frequency of gram-negative bacilli infection, with a high percentage of multiresistant microorganisms and high resistance to empirical antibiotic treatment.BACKGROUND: Bloodstream infection is a common complication, which can be life-threatening for hematopoietic stem cells transplant recipients. OBJECTIVE: To analyze the characteristics of bloodstream infections in hematopoietic stem cell transplant recipients. MATERIALS AND METHODS: Observational, retrospective study. We reviewed the records of 451 patients (autologous and allogeneic transplants) from January 2009 to October 2015. RESULTS: 99 positive blood cultures in 73 patients with bloodstream infection (16%) were found. Mortality attributable to infectious causes was 17%. From the 99 bloodstream infection, 63% were caused by gram-negative bacilli (Escherichia coli 45%, Klebsiella spp 23%, Pseudomonas spp 11% Acinetobacter spp % and other bacilli 15%), 33% by gram-positive cocci, 3% by fungi and 1% by gram-positive bacilli. The gram-negative bacilli were ciprofloxacin resistant (81%), piperacillin/tazobactam resistant (48%), extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae (40%), cefepime resistant (39%) and there was no resistance noted to amikacin. DISCUSSION: There is a higher frequency of gram-negative bacilli infection, with a high percentage of multiresistant microorganisms and high resistance to empirical antibiotic treatment.