Effects of NO/cGMP inhibitors in a rat model of anaphylactoid shock

Anaphylactic shock can be defined as an acute syndrome, and it is the most severe clinical manifestation of allergic diseases. Anaphylactoid reactions are similar to anaphylactic events but differ in the pathophysiological mechanism. Nitric oxide (NO) inhibitors during anaphylaxis suggest that NO might decrease the signs and symptoms of anaphylaxis but exacerbate associated vasodilation. Therefore, blocking the effects of NO on vascular smooth muscle by inhibiting the guanylate cyclase (GC) would be a reasonable strategy. This study aimed to investigate the effects of NO/cGMP pathway inhibitors methylene blue (MB), Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME), and indigo carmine (IC) in shock induced by compound 48/80 (C48/80) in rats. The effect was assessed by invasive blood pressure measurement. Shock was initiated by C48/80 intravenous bolus injection 5 min before (prophylactic) or after (treatment) the administration of the inhibitors MB (3 mg/kg), L-NAME (1 mg/kg), and IC (3 mg/kg). Of the groups that received drugs as prophylaxis for shock, only the IC group did not present the final systolic blood pressure (SBP) better than the C48/80 group. Regarding shock treatment with the drugs tested, all groups had the final SBP similar to the C48/80group. Altogether, our results suggested that inhibition of GC and NO synthase in NO production pathway was not sufficient to revert hypotension or significantly improve survival.

Reconocimiento y manejo de la anafilaxia en pediatría / Detection and management of anaphylaxis in children

INTRODUCCIÓN: La anafilaxia es una emergencia. De acuerdo con las últimas recomendaciones internacionales el reconocimiento de los criterios clínicos y el tratamiento temprano con adrenalina intramuscular se asocian a mayor sobrevida. OBJETIVO: Determinar el conocimiento de los médicos pediatras de un Hospital Pediátrico de tercer nivel sobre los criterios diagnósticos y el tratamiento de la anafilaxia. MATERIAL Y MÉTODO: Estudio descriptivo transversal que considera diseño, aplicación y validación de una encuesta anónima a médicos con residencia completa en pediatría que realizan guardias en un hospital de tercer nivel. Los ítems de la Encuesta comprendieron tres dimensiones, experiencia del operador (2 ítems), manejo farmacológico (3 ítems) e identificación del cuadro (4 ítems). El análisis estadístico utilizó el programa SPSS v.21, presentando medidas de tendencia central (mediana, rango y tabla de frecuencias) y para su comparación prueba de Chi cuadrado. Se consideró significativo un valor de p < 0,05. RESULTADOS: Se encuestaron 71 médicos con una mediana de 3 años transcurridos desde el fin de la residencia. 35% identificó todos los criterios clínicos; 99% (70) indicó adrenalina, 73% por vía intramuscular y 55% a dosis correcta (solo el 48% contestó la dosis y vía correctamente). En forma global la adecuación para identificación más manejo correcto fue del 21%. Los médicos con menos de 5 años de experiencia tuvieron mejor desempeño en la administración de adrenalina intramuscular (83% vs 52% p = 0,005) y en la detección de síntomas gastrointestinales (60%vs35% p = 0,043). CONCLUSIONES: Existen dificultades para la identificación y el manejo apropiado de la anafilaxia por pediatras de un Hospital de tercer nivel en un escenario teórico. Aunque la mayoría eligió la adrenalina como droga de primera línea, la mitad no la indicó de forma correcta y solo un tercio reconoció el cuadro en todos sus escenarios.

INTRODUCTION: Anaphylaxis is an emergency condition. According to the latest international guide lines, early recognition and treatment with intramuscular epinephrine are associated with increased survival. OBJECTIVE: To determine the level of knowledge of pediatricians in a tertiary Pediatric Hos pital about the diagnostic criteria and treatment of anaphylaxis. MATERIAL AND METHOD: A cross-sec tional descriptive study was conducted, designing, applying, and validating an anonymous survey to physicians with complete residency in pediatrics who are on call at a third level hospital. The statisti cal analysis was made using the SPSS v.21 software, presenting measures of central tendency (median, range, and frequency table) and Chi-square test for comparison. A value of p < 0.05 was considered significant. RESULTS: 71 physicians completed the survey with a median of three years after the end of residency.35% of them identified all clinical criteria, 99% (70) indicated epinephrine, 73% chose the intramuscular route, and 55% indicated the correct dose. Only 48% of responders chose the dose and administration route correctly. In general, 21% recognized anaphylaxis and used epinephrine correctly. Physicians with less than five years of experience performed better in the intramuscular administration of epinephrine (83% vs 52% p = 0.005) and in the detection of gastrointestinal symp toms (60% vs 35% p = 0.043). CONCLUSIONS: There are difficulties in the identification and proper management of anaphylaxis by pediatricians of a tertiary Pediatric Hospital in a theoretical clinical setting. Although most of pediatricians chose epinephrine as a first-line drug, half of them did not indicate it correctly, and only one-third recognized anaphylaxis in all scenarios.

Diagnosis and treatment of anaphylaxis: there is an urgent needs to implement the use of guidelines / Diagnóstico e tratamento da anafilaxia: há necessidade urgente de implementar o uso das diretrizes

ABSTRACT Anaphylaxis is a severe, life-threatening generalized or systemic hypersensitivity reaction that requires rapid and adequate care. This study aimed to obtain an integrated view of the level of physicians' knowledge related with treatment of anaphylaxis in studies published within the last 5 years. Sixteen studies were found and four points were identified as of the great interest to the authors: (1) emergency pharmacological treatment, (2) epinephrine auto-injectors prescription, (3) knowledge of the main signs of anaphylaxis, and (4) admission of the patient to verify biphasic reactions. Concern about the use of intramuscular adrenaline as the first choice in relation with anaphylaxis was evident in most studies, rather than its use in the comparison dial, and especially low in a study that included data from Brazil, in which the frequency of its use was 23.8%. An adrenaline autoinjector is highly recommended among specialists for patients at risk of anaphylaxis, however, its use is still infrequent among non-specialists and in countries that this agent is not available. Intervention studies have shown improved medical knowledge of anaphylaxis following disclosure of the information contained in the international guidelines. The analysis of these studies reinforces the need to disseminate international guidelines for diagnosis and treatment of anaphylaxis, as well as providing an adrenaline autoinjector, to improve management and to prevent a fatal outcome.

RESUMO Anafilaxia é uma reação de hipersensibilidade generalizada ou sistêmica grave, com risco de morte, que exige atendimento rápido e correto. Este estudo teve como objetivo obter uma visão integrada do nível de conhecimento dos médicos no atendimento da anafilaxia à luz dos estudos publicados internacionalmente nos últimos 5 anos. Foram encontrados 16 estudos, com quatro pontos identificados como de maior interesse dos autores: (1) tratamento farmacológico de emergência, (2) prescrição de autoinjetores de adrenalina, (3) conhecimento dos principais indícios da anafilaxia e (4) observação do paciente para verificar reações bifásicas. A preocupação com o uso da adrenalina intramuscular como primeira escolha frente à anafilaxia foi evidente na maioria dos estudos, mas o conhecimento sobre seu uso se mostrou desigual e especialmente baixo em estudo que incluiu dados do Brasil, onde a frequência de seu uso foi de 23,8%. A adrenalina autoinjetável é altamente recomendada entre especialistas para pacientes em risco de anafilaxia, mas seu uso ainda é pouco frequente entre não especialistas e em países que não dispõem dela em seus mercados internos. Estudos de intervenção comprovaram a melhora no entendimento dos médicos sobre anafilaxia após a divulgação das informações contidas nas diretrizes internacionais. A análise dos estudos reforça a necessidade de disseminar as diretrizes internacionais no manejo da anafilaxia, bem como de disponibilizar a adrenalina autoinjetável, a fim de melhorar o atendimento e evitar um desfecho fatal.

Actualización en las recomendaciones del tratamiento del choque anafiláctico: novedades sobre el uso de adrenalina / Update on anaphylactic shock treatment recommendations: What's new in the use of epinephrine?

En 1998, la Sociedad Argentina de Pediatría publicó la recomendación del tratamiento del choque anafiláctico. Mientras en dicha recomendación se sugería el uso de adrenalina por vía subcutánea, actualmente se considera la vía intramuscular como la más adecuada. Aspectos farmacodinámicos determinan esta preferencia. Para el tratamiento extrahospitalario, el uso de autoinyectores de manera correcta puede colaborar en el control rápido y eficaz de la afección. El uso del resto de las medicaciones propuestas en la recomendación de 1998 se mantiene sin cambios.

In 1998, the Sociedad Argentina de Pediatría issued the recommendation of the treatment of anaphylactic shock. While this recommendation suggested the use of subcutaneous epinephrine, currently the intramuscular via is considered the most appropriate one. Pharmacological aspects determine this preference. For outpatient treatment, the correct use of autoinjectors can control anaphylaxis quickly and effectively. The use of other medications in the proposed 1998 recommendation remains unchanged.

Caso de anafilaxia induzida por rocurônio tratado com o auxílio de sugamadex / Case of anaphylaxis induced by rocuronium treated with sugammadex / Caso de anafilaxia inducida por rocuronio tratado con la ayuda del sugamadex

JUSTIFICATIVA E OBJETIVOS: A anafilaxia durante a anestesia é um evento raro que pode ocorrer em até 1:20.000 casos sendo que aproximadamente 60% a 70% destes casos são secundários ao uso de ralaxantes musculares onde os mais implicados a succinilcolina e o rocurônio. O objetivo deste relato foi descrever o tratamento de um caso de anafilaxia induzida por rocurônio com resposta inadequada a terapia tradicional e resolução do caso após o uso do sugamadex. RELATO DO CASO: Paciente do sexo feminino, com 62 anos de idade, 72 kg, foi encaminhada ao centro cirúrgico para tratamento de hematoma extradural após acidente em domicílio. Foi monitorada com oxímetro de pulso, cardioscópio e tensiômetro para medida da pressão anterial não invasiva (PA). Seus dados basais foram: PA de 138/80 mm Hg, frequência cardíaca (FC) de 80 bpm e saturação arterial (SaO2) de 100% em ar ambiente. A indução da anestesia se processou com propofol 70 mg, fentanil 200 µg e rocurônio 45 mg. Após a intubação traqueal, diagnosticou-se quadro de anafilaxia que não respondeu ao tratamento convencional. Optou-se pelo uso de sugamadex 700 mg por via venosa como agente coadjuvante. A paciente apresentou reversão do quadro com melhora do perfil hemodinâmico sendo operada e conduzida à unidade de terapia intensiva. CONCLUSÃO: Neste caso, o sugamadex foi utilizado para reverter quadro hemodinâmico induzido pela anafilaxia por rocurônio, entretanto não foi possível esclarecer qual o mecanismo exato para a reversão do quadro hemodinâmico.

BACKGROUND AND OBJECTIVES: Anaphylaxis during anesthesia is a rare event that may occur in up to 1:20,000 cases and approximately 60% to 70% of these cases are secondary to the use of muscle relaxants, particularly succinylcholine and rocuronium. The aim of this report is to describe the treatment of a case of rocuronium-induced anaphylaxis with inadequate response to traditional therapy, and the case resolution after using sugammadex. CASE REPORT: A female patient, 62 years old, 72 kg, was referred to the surgical center for treatment of epidural hematoma following an accident at home. She was monitored with pulse oximetry, cardioscope, and blood pressure meter for non-invasive blood pressure (BP) measurement. The baseline data were: BP 138/80 mm Hg, heart rate (HR) 80 bpm, and oxygen saturation (SaO2) 100% on room air. Anesthesia was induced with propofol 70 mg, fentanyl 200 mg, and rocuronium 45 mg. After tracheal intubation, anaphylaxis non-responsive to conventional treatment was diagnosed. We chose the use of sugammadex 700 mg intravenously as an adjuvant agent. The patient had reversal of the anaphylactic reactions with improvement of hemodynamic profile and was operated and conducted to the intensive care unit. CONCLUSION: In this case, sugammadex was used to reverse the hemodynamic picture caused by rocuronium-induced anaphylaxis. However, it was not possible to identify the exact mechanism for the reversal.

JUSTIFICATIVA Y OBJETIVOS: La anafilaxia durante la anestesia es un evento raro que puede ocurrir hasta en 1: 20.000 casos siendo que aproximadamente entre un 60% a un 70% de ellos son secundarios al uso de relajantes musculares donde los más implicados son la succinilcolina y el Rocuronio. El objetivo de este relato, fue describir el tratamiento de un caso de anafilaxia inducida por Rocuronio con una respuesta inadecuada a la terapia tradicional y la solución del caso después del uso del sugamadex. RELATO DEL CASO: Paciente del sexo femenino, 62 años, 72 kg, derivada al quirófano para tratamiento de hematoma extradural posterior a accidente en domicilio. Fue monitorizada con oxímetro de pulso, cardioscopio y tensiómetro para la medida de la presión arterial no invasiva (PA). Sus datos basales fueron los siguientes: PA de 138/80 mm Hg, frecuencia cardíaca (FC) de 80 lpm y saturación arterial (SaO2) de 100% en aire ambiente. La inducción de la anestesia fue procesada con propofol 70 mg, fentanil 200 µg y Rocuronio 45 mg. Después de la intubación traqueal se diagnosticó un cuadro de anafilaxia que no respondió al tratamiento convencional. Optamos entonces por el uso del sugamadex 700 mg por vía venosa como agente coadyuvante. La paciente presentó una reversión del cuadro con una mejoría del perfil hemodinámico siendo operada y derivada a la unidad de cuidados intensivos. CONCLUSIONES: En este caso, el sugamadex fue utilizado para revertir el cuadro hemodinámico inducido por la anafilaxia por Rocuronio, pero no se pudo aclarar cuál sería el mecanismo exacto para la reversión del cuadro hemodinámico.

Methylene blue administration in the compound 48/80-induced anaphylactic shock: hemodynamic study in pigs / Administração de azul de metileno no choque anafilático induzido por composto 48/80: estudo hemodinâmico em suínos

PURPOSE: To verify if the methylene blue (MB) administration prevents and/or reverses the compound 48/80 (C48/80)-induced anaphylactic shock in pigs. METHODS: Female Dalland pigs were anesthetized and had the hemodynamic parameters recorded during the necessary time to administer some drugs and observe their effect. The animals were randomly assigned to one of the five groups: 1) control; 2) MB: the animals received a bolus injection of MB (2 mg/kg) followed by continuous infusion of MB (2.66 mg/Kg/h delivered by syringe infusion pump); 3) C48/80: the animals received a bolus injection of C48/80 (4 mg/kg); 4) C48/80+MB: the animals received a bolus injection of C48/80 (4 mg/kg) and 10 minutes after the C48/80 administration the animals received a bolus injection of MB (2 mg/kg) followed by continuous infusion of MB (2.66 mg/Kg/h delivered by syringe infusion pump); 5) MB+C48/80: the animals received a bolus injection of MB (2 mg/kg) and 3 minutes later they received a bolus injection of C48/80 (4 mg/kg). RESULTS: The intravenous infusion of MB alone caused no changes in the mean arterial pressure (MAP) showing that the administered MB dose was safe in this experimental model. The C48/80 was effective in producing experimental anaphylactic shock since it was observed a decrease in both MAP and cardiac output (CO) after its administration. The MB did not prevent or reverse the C48/80-induced anaphylactic shock in this model. In fact, the MAP of the animals with anaphylactic shock treated with MB decreased even more than the MAP of the animals from the C48/80 group. On the other hand, the C48/80-induced epidermal alterations disappeared after the MB infusion. CONCLUSION: Despite our data, the clinical manifestations improvement brings some optimism and does not allow excluding the MB as a possible therapeutic option in the anaphylactic shock.

OBJETIVO: Verificar se a administração de azul de metileno (AM) previne e/ou reverte o choque anafilático induzido por composto 48/80 (C48/80) em suínos. MÉTODOS: Porcos fêmeas Dalland foram anestesiados e tiveram os parâmetros hemodinâmicos registados durante o tempo necessário para administrar algumas drogas e observar seu efeito. Os animais foram aleatoriamente destribuídos em um dos cinco grupos: 1) controle, 2) AM: os animais receberam uma injeção em bolus de AM (2mg/kg), seguido de infusão contínua de AM (2,66mg/Kg /h por bomba de infusão de seringa); 3) C48/80: os animais receberam uma injeção em bolus de C48/80 (4mg/kg); 4) C48/80 + AM: os animais receberam uma injeção em bolus de C48/80 (4mg/kg) e 10 minutos após a administração de C48/80 os animais receberam uma injeção em bolus de AM (2mg/kg), seguido de infusão contínua de AM (2,66mg/kg/h por bomba de infusão de seringa); 5) AM+C48/80: os animais receberam uma injeção em bolus de AM (2mg/kg) e três minutos depois, receberam uma injeção em bolus de C48/80 (4mg/kg). RESULTADOS: A infusão intravenosa de AM não causou mudanças na pressão arterial média (PAM), mostrando que a dose de AM administrada foi segura neste modelo experimental. O C48/80 foi eficaz na indução do choque anafilático experimental, uma vez que foi observada redução na PAM e débito cardíaco (DC), após a sua administração. O AM não preveniu ou reverte o choque anafilático induzido por C48/80 neste modelo. Na verdade, a PAM dos animais com choque anafilático tratados com AM diminuiu mais do que o PAM dos animais do grupo C48/80. Por outro lado, as alterações epidérmicas induzidas pelo C48/80 desapareceu após a infusão do AM. CONCLUSÃO: Apesar dos resultados a melhora clínica das manifestações anafiláticas permite considerar a possibilidade do azul de metileno como opção terapêutica no tratamento do choque anafilático.

Quercetin as a potential anti-allergic drug: which perspectives?

Flavonoids polyphenolic compounds that exert many anti-inflammatory and anti-microbial effects, and exhibit an anti-allergic action. Quercetin is a flavonoids that recently has raised many issues and shown evidence about its action as a potential drug to allergy. A Chinese herbal formula, known as Food Allergy Herbal Formula [FAHF] has been related with blocking of anaphylaxis to peanuts [PNA] in mouse models. Quercetin appears to possess the same potential of FAHF as a safe anti-allergic substance but it opens only a wide perspective, at the moment, due to several complex issues that hamper the possibility to use natural medicine and phytochemicals as true drugs

Anaphylaxis in Latin America: a report of the online Latin American survey on anaphylaxis (OLASA)

OBJECTIVES: The aims of the Online Latin American Survey of Anaphylaxis (OLASA) were to identify the main clinical manifestations, triggers, and treatments of severe allergic reactions in patients who were seen by allergists from July 2008 to June 2010 in 15 Latin American countries and Portugal (n =634). RESULTS: Of all patients, 68.5 percent were older than 18 years, 41.6 percent were male, and 65.4 percent experienced the allergic reaction at home. The etiologic agent was identified in 87.4 percent of cases and predominantly consisted of drugs (31.2 percent), foods (23.3 percent), and insect stings (14.9 percent). The main symptom categories observed during the acute episodes were cutaneous (94.0 percent) and respiratory (79.0 percent). The majority of patients (71.6 percent) were treated initially by a physician (office/emergency room) within the first hour after the reaction occurred (60.2 percent), and 43.5 percent recovered in the first hour after treatment. Most patients were treated in an emergency setting, but only 37.3 percent received parenteral epinephrine alone or associated with other medication. However, 80.5 percent and 70.2 percent were treated with corticosteroids or antihistamines (alone or in association), respectively. A total of 12.9 percent of the patients underwent reanimation maneuvers, and 15.2 percent were hospitalized. Only 5.8 percent of the patients returned to the emergency room after discharge, with 21.7 percent returning in the first 6 hours after initial treatment. CONCLUSION: The main clinical manifestations of severe allergic reactions were cutaneous. The etiologic agents that were identified as causing these acute episodes differed according to age group. Following in order: drugs (31.2 percent), foods (23.3 percent and insect stings (14.9 percent) in adults with foods predominance in children. Treatment provided for acute anaphylactic reactions was not appropriate. It is necessary to improve educational programs in order to enhance the knowledge on this potentially fatal emergency.

Evaluation of anti-allergic activity of gossypin and suramin in mast cell-mediated allergy model.

The mast cell-mediated allergic reactions are involved in many allergic diseases, such as asthma, allergic rhinitis and sinusitis. Stimulation of mast cells initiates the process of degranulation, resulting in the release of mediators such as histamine and an array of inflammatory cytokines. In this report, we investigated the effect of gossypin (a biflavonoid) and suramin (a synthetic polysulphonated naphtylurea) on the mast cell-mediated allergy model, and studied the possible mechanism of their action. Both gossypin and suramin inhibited (P<0.001) compound 48/80-induced systemic anaphylaxis reactions, antiprurities (P<0.001) and reduced the histamine release in rats. Further, both showed significant (P<0.001) protection against rat peritoneal mast cells activated by compound 48/80. Thus, our findings provide evidence that gossypin and suramin inhibit mast cell-derived allergic reactions.

Black ant stings caused by Pachycondyla sennaarensis: a significant health hazard

Several species of ants cause stings, but not all lead to allergic reactions. We present a series of cases of allergic reactions following insect bites or stings that presented to our emergency department and that were caused by the black samsum ant [Pachycondyla sennaarensis]. Reactions ranged from mild allergic reactions to severe anaphylactic shock. Patients were treated with subcutaneous epinephrine 0.3 mg, intravenous methylprednisolone 125 mg, intravenous diphenhydramine HCl 50 mg, and intravenous normal saline as appropriate. These cases illustrate the range of clinical presentations to black ant stings, which can include severe reactions, indicating that ant stings are a significant public health hazard in Saudi Arabia. Physicians in the Middle East and Asia need to be aware of ant stings as a cause of severe allergic reactions

The utility of the World Health Organization-The Uppsala Monitoring Centre (WHO-UMC) system for the assessment of adverse drug reactions in hospitalized children.

Although the World Health Organization-The Uppsala Monitoring Centre (WHO-UMC) system has been suggested as a practical tool for classifying adverse drug reactions (ADRs), verification of such system has not been examined. The objective of this study was to evaluate the usefulness of the WHO-UMC classification for the diagnosis of ADRs. The gold standard was the results of drug challenges and serum tryptase in cases of anaphylaxis. Twenty-seven children had ADRs classified by the WHO-UMC system. The causality terms were 'certain' in 4/27, 'probable' in 6/27, 'possible' in 10/27 and 'unlikely' in 7/27 of the patients. Skin prick tests and intradermal tests were positive in 1/20 and 1/5 of the patients, respectively. Drug challenges and serum tryptase were positive in 8/26 and 1/3 of the patients, respectively. After complete evaluation, the positive and negative ADRs were documented in 9/27 patients (33.33%) and 18/27 patients (66.67%), respectively. The multi-level likelihood ratios for ADRs using the WHO-UMC system were infinity in causality term 'certain', 2 in 'probable', 0.5 in 'possible', and 0 in 'unlikely'. In conclusion, causality term 'certain' and 'unlikely' of the WHO-UMC system had large impact on the likelihood of ADRs. In contrast, the causality term 'probable' and 'possible' had small impact on the likelihood of ADRs. Drug challenges and serum tryptase were helpful to confirm ADRs categorized by WHO-UMC system.

Methylene blue for clinical anaphylaxis treatment: a case report

CONTEXT AND OBJECTIVE: Nitric oxide has a pathophysiological role in modulating systemic changes associated with anaphylaxis. Nitric oxide synthase inhibitors may exacerbate bronchospasm in anaphylaxis and worsen clinical conditions, with limited roles in anaphylactic shock treatment. The aim here was to report an anaphylaxis case (not anaphylactic shock), reversed by methylene blue (MB), a guanylyl cyclase inhibitor. CASE REPORT: A 23-year-old female suddenly presented urticaria and pruritus, initially on her face and arms, then over her whole body. Oral antihistamine was administered initially, but without improvement in symptoms and signs until intravenous methylprednisolone 500 mg. Recurrence occurred after two hours, plus vomiting. Associated upper respiratory distress, pulmonary sibilance, laryngeal stridor and facial angioedema (including erythema and lip edema) marked the evolution. At sites with severe pruritus, petechial lesions were observed. The clinical situation worsened, with dyspnea, tachypnea, peroral cyanosis, laryngeal edema with severe expiratory dyspnea and deepening unconsciousness. Conventional treatment was ineffective. Intubation and ventilatory support were then considered, because of severe hypoventilation. But, before doing that, based on our previous experience, 1.5 mg/kg (120 mg) bolus of 4 percent MB was infused, followed by one hour of continuous infusion of another 120 mg diluted in dextrose 5 percent in water. Following the initial intravenous MB dose, the clinical situation reversed completely in less than 20 minutes, thereby avoiding tracheal intubation. CONCLUSION: Although the nitric oxide hypothesis for MB effectiveness discussed here remains unproven, our intention was to share our accumulated cohort experience, which strongly suggests MB is a lifesaving treatment for anaphylactic shock and/or anaphylaxis and other vasoplegic conditions.

CONTEXTO E OBJETIVO: O óxido nítrico (NO) tem papel fisiopatológico na modulação das alterações sistêmicas associadas à anafilaxia. Inibidores da sintase do NO podem exacerbar a broncoconstrição na anafilaxia e piorar as condições clínicas e têm um papel limitado no tratamento do choque anafilático. O objetivo deste relato foi o de apresentar um caso de anafilaxia (não-choque anafilático) revertido pela inibição da guanilato ciclase pelo azul de metileno. RELATO DE CASO: Mulher de 23 anos apresentou repentina urticária e prurido, inicialmente localizados na face e nos braços, que se estenderam para quase todo o corpo. Utilizou-se, inicialmente, anti-histamínico, mas pequena melhora só foi observada após o uso endovenoso de 500 mg metilprednisolona. Após duas horas, os sintomas voltaram acompanhados de vômitos. Observou-se dificuldade respiratória alta, sibilos respiratórios, estridores laríngeos, angioedema facial, incluindo eritema, edema de lábios e, nos locais de intenso prurido, observaram-se petéquias. O quadro agravou-se com dispnéia, taquipnéia, parestesia peroral, edema laríngeo, grave dispnéia expiratória com crescente perda da consciência. O tratamento convencional não foi efetivo. Considerou-se intubação pela grave hipoventilação. Com base em nossa prévia experiência, um bolo endovenoso de 1,5 mg/kg (120 mg) de azul de metileno a 4 por cento diluído em soro glicosado 5 por cento, seguido de outros 120 mg infundidos durante uma hora. Após a dose endovenosa inicial do azul de metileno, a situação clínica reverteu-se completamente, evitando-se a intubação traqueal. CONCLUSÃO: Embora a hipótese da eficácia da relação entre o óxido nítrico e o azul de metileno ainda esteja por ser provada, nossa intenção foi de compartilhar nossa experiência acumulada, que sugere fortemente que o azul de metileno seja um tratamento salvador de vidas para o choque anafilático e/ou anafilaxia e outras condições vasoplégicas.

Black [samsum] ant induced anaphylaxis in Saudi Arabia

Ant allergy is a rare clinical problem that ranges from local to systemic reaction and life-threatening anaphylaxis. Different types of ants including the imported fire ants, the black [samsum] ants, and others, are considered health hazard in many parts of the world. We report a 32-year-old Saudi female from Hafr-Al-Batin in the Northern region of Saudi Arabia, with history of recurrent anaphylaxis following black [samsum] ant stings and we review the related literature. This is the first report of black [samsum] ant allergy in Saudi Arabia

Reacciones anafilácticas / Anaphylactic reactions

La anafilaxia se define como una reacción sistémica generalizada caracterizada por síntomas y signos de rápida instalación después de la exposición a un antígeno en personas previamente sensibilizadas.

Evaluation of E-721B, an indigenous herbal combination in experimental models of immediate hypersensitivity.

E-721B, an indigenous herbal combination was investigated for its usefulness in immediate hypersensitivity using different animal models. The drug inhibited the mast cell degranulation induced both by antigen and compound 48/80, the Schultz-Dale response in sensitized guinea pig ileum smooth muscle preparation and the production of precipitating antibodies in 50% of tested rats. It also inhibited the mast cell degranulation in passively sensitized rats indicating its suppressive action on production of reaginic antibody (IgE). However, the drug did not inhibit the 48 hours passive cutaneous anaphylaxis reaction in rats, indicating that a single dose of the drug does not have cromoglycate like properties. All the above results indicate the inhibitory effect of E-721B on immediate hypersensitive reactions such as asthma.