Anaphylaxis.docx

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Anaphylaxis Definition Anaphylaxis is a rapidly progessing, life-threatening allergic reaction. Description Anaphylaxis is a type of allergic reaction, in which the immune system responds to otherwise harmless substances from the environment. Unlike other allergic reactions, however, anaphylaxis can kill. Reaction may begin within minutes or even seconds of exposure, and rapidly progress to cause airway constriction, skin and intestinal irritation, and altered heart rhythms. In severe cases, it can result in complete airway obstruction, shock, and death. Causes and symptoms Causes Like the majority of other allergic reactions, anaphylaxis is caused by the release of histamine and other chemicals from mast cells. Mast cells are a type of white blood cell and they are found in large numbers in the tissues that regulate exchange with the environment: the airways, digestive system, and skin. On their surfaces, mast cells display antibodies called IgE (immunoglobulin type E). these antibodies are designed to defect environmental substances to which the immune system is sensitive. Substances from a genuinely threatening source, such as bacteria or viruses, are called antigens. A substance that most people tolerate well, but to which allergens others have an allergic response, is called an allergen. When IgE antibodies bind with allergens, they cause the mast cell to release histamine and other chemicals, which spill out onto neighboring cells. The interaction of these chemicals with receptors on the surface of blood vessels causes the vessels to leak fluid into surrounding tissue, causing fluid accumulation, redness, and swelling. On the smooth muscle cells of the airways and digestive

Transcript of Anaphylaxis.docx

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Anaphylaxis

DefinitionAnaphylaxis is a rapidly progessing, life-threatening allergic reaction.

DescriptionAnaphylaxis is a type of allergic reaction, in which the immune system responds to

otherwise harmless substances from the environment. Unlike other allergic reactions, however, anaphylaxis can kill. Reaction may begin within minutes or even seconds of exposure, and rapidly progress to cause airway constriction, skin and intestinal irritation, and altered heart rhythms. In severe cases, it can result in complete airway obstruction, shock, and death.

Causes and symptoms

CausesLike the majority of other allergic reactions, anaphylaxis is caused by the release of

histamine and other chemicals from mast cells. Mast cells are a type of white blood cell and they are found in large numbers in the tissues that regulate exchange with the environment: the airways, digestive system, and skin.

On their surfaces, mast cells display antibodies called IgE (immunoglobulin type E). these antibodies are designed to defect environmental substances to which the immune system is sensitive. Substances from a genuinely threatening source, such as bacteria or viruses, are called antigens. A substance that most people tolerate well, but to which allergens others have an allergic response, is called an allergen. When IgE antibodies bind with allergens, they cause the mast cell to release histamine and other chemicals, which spill out onto neighboring cells.

The interaction of these chemicals with receptors on the surface of blood vessels causes the vessels to leak fluid into surrounding tissue, causing fluid accumulation, redness, and swelling. On the smooth muscle cells of the airways and digestive system, they cause constriction. On nerve endings, they increase sensitivity and cause itching.

In anaphylaxis, the dramatic response is due to extreme hypersensitivity to the allergen and its usually systemic distribution. Allergen are more likely to cause anaphylaxis if they are introduced directly into the circulatory system by injection.

However, exposure by ingestion, inhalation, or skin contact can also cause anaphylaxis. In some cases, anaphylaxis may develop over time from less severe allergies. Anaphylaxis is most often due to allergens in foods, drugs, and ansect venom. Specific causes include:

Fish, shellfish, and mollusks Nuts and seeds Stings of bees, wasps, or hornets Papain from meat tenderizers Vaccines, including flu and measles vaccines Penicilin Cephalosporins Streptomycin Gamma globulin

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Insulin Hormones (ACTH, thyroid-stimulating hormone) Aspirin and other NSAIDs Latex, from exam gloves or condoms, for example.

SymptomsSymptoms may include:- Urticaria (hives)- Swelling and irritation of the tongue or mouth- Swelling of the sinuses- Difficulty breathing- Wheezing- Cramping, vomiting, or diarrhea- Anxiety or confusion- Strong, very rapid heartbeat (palpitations)- Loss of consciousnessNot all symptoms may be present

DiagnosisAnaphylaxis is diagnosed based on the rapid development of symptoms in response to a

suspect allergen. Identification of the culprit may be done with RAST testing, a blood test that identifies IgE reactions to specific allergens. Skin testing may be done for less severe anaphylatic reactions.

Anaphylaxis is an acute, potentially lethal, multisystem syndrome resulting from the sudden release of mast cell and basophil-derived mediators into the circulation. It most often results from immulogic reactions to foods, medications, and insect stings, although it can also be induced through nonimmulogic mechanisms by any agent capable of producing a sudden, systemic degranulation of mast cells or basophils.

The phenomenen of anaphylaxis was first described in the modern medical lirerature in 1902 in a study involving protocols for immunizing dogs with jellyfish toxin. The injection of small amounts of toxin in some animals, rather than generating protection, precipitated the rapid onset of fatal or near-fatal symptoms. The authors named this response “1’anaphylaxie,” which is derived from derived from the Greek words a- (against) and phylaxis (immunity or protection).

Anaphylaxis is a systemic, type I hypersensitivity reaction that often has fatal consequences. Anaphylaxis has a variety of causes including foods, latex, drugs, and hymenoptera venom. Epinephrine given early is the most important intervention. Adjunctive treatments injclude fluid therapy, H (1) anjd H (2) histamine receptor antagonists, corticosteroids, and bronchodilators; however these do not substitute for epinephrine. Patients with a hystory of anaphylaxis should be educated about their condition, especially with respect to trigger avoidance and in the correct use of epinephrine autoinjector kits. Such kits should be available to the sensitized patient at all times.

Anaphylaxis is an acute fatal or potentially fatal hypersensitivity reation. Anaphylaxis represent a clinical diagnosis based on history and physical examination and includes symptoms of airway obstruction, generalized skin reactions, particularly flushing, itching, urticaria, angioedema cardiovascular symptoms including hypotension and gastrointestinal symptoms.

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These symptoms result from the action of mast cell mediators, especially histamine and lipid mediators such as leukotriens and plaelet activiting factor on shock tissue. The shock tissue includes blood vessels, mucous glands, smooth muscle, and nerve endings.

Anaphylaxis follows the typical immediate hypersensitity time course, with a reaction beginning within minutes of antigen exposure. A late-phase reaction hours after the initial reaction may occur. Mast cell mediator release can be triggered by both IgE and non-IgE mediated factors. Therefore, anaphylaxis may be termed anphylaxis (IgE mediated) or anaphylactoid (non-IgE mediated). The most common IgE mediated triggers are drugs, typically penicillin or other beta-lactam antibiotics, foods, most commonly nuts, peanuts, fish and shellfish, or hymenoptera stings. Non- IgE mediated causes include factors causing marked complement activation such as plasma proteins or compounds which act on the mast cell membrane, such as vancomycin, quinolone antibiotics, or radiographic contrast media. The pathophysiology of some trigger factor, such us aspirin, remains unclear.

Therapy of anaphylaxis revolves around patient education, avoidance, desensitization or pharmacologic pretreatment when agents causing anaphylaxis need to be readministered, and early recognition and prompt therapy of reactions should they occur.

IgE-dependent and IgE-independent hypersensitivity reactions, the latter due to physical, chemical or hyperosmolar stimuli, may evolve as anaphylaxis or an anaphylactoid reaction, by an escalating release of mediators from mast cell and basophils. Without immediete treatment, anaphylaxis goes along with substansial morbidity (shock, multiple organ failure) and mortality; within minutes this explosive clinical response can be fatal. The severity of anaphylactic/anaphylactoid reactions is graded from stages 0 to IV in order to guide the management of this disease, stage III corresponding to anaphylactic shock. Severe anaphylactic reactions may take progressive course despite adequate therapy; even in the case of an initial favourable response to treatment measures life-trheatening symptoms may recur; there may be late-phase reactions 6 to 12 hour after the initial reaction.

For the initial emergency management a differentiation between IgE mediated and IgE independent anaphylactoid reactions is not required. These are the pertinent principles of therapy in hypotensive and hypoxic patient: removal of the likely noxious agent at the site of introduction, provision of a patient airway, 100% oxygen supplementation, intravenous fluid therapy and phamacological support with catecholamines. After primary care the monitoring and therapy of the patient with anaphylactic shock has to be continued on the intensive care unit. Guideliness for management af acute anaphylaxis referring to both the stage of disease including shock and the main clinical manifestation (cutaneous, pulmonay, cardiovascular) have been established by a German interdisciplinary consensus conference and were published in 1994; consensus guideliness for emergency medical treatment have been communicated by the ILCOR (1997) and the project team of the Resuscitation Council (UK) (1999).

Shock (shok)1. A sudden disturbance of mental equilibrium2. A profound hemodynamic and metabolic disturbance due to failure of the

circulatory system to maintain adequate perfusion of vital organs.

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anafilaksis

definisiAnafilaksis adalah berkembang pesat, reaksi alergi mengancam nyawa.

deskripsiAnafilaksis adalah jenis reaksi alergi, di mana sistem kekebalan tubuh merespon zat yang tidak

berbahaya lain dari lingkungan. Tidak seperti reaksi alergi lainnya, bagaimanapun, anafilaksis dapat membunuh. Reaksi dapat dimulai dalam beberapa menit atau bahkan detik dari eksposur, dan berkembang cepat menyebabkan penyempitan saluran napas, iritasi kulit dan usus, dan irama jantung berubah. Dalam kasus yang berat, dapat mengakibatkan obstruksi jalan napas lengkap, syok, dan kematian.

Penyebab dan Gejala

penyebabSeperti sebagian besar reaksi alergi lainnya, anafilaksis disebabkan oleh pelepasan histamin dan

bahan kimia lainnya dari sel mast. Sel mast adalah jenis sel darah putih dan mereka ditemukan dalam jumlah besar dalam jaringan yang mengatur pertukaran dengan lingkungan: saluran udara, sistem pencernaan, dan kulit.

Pada permukaannya, sel mast menampilkan antibodi disebut IgE (immunoglobulin tipe E). antibodi ini dirancang untuk merusak zat lingkungan dimana sistem kekebalan tubuh sensitif. Zat dari sumber yang benar-benar mengancam, seperti bakteri atau virus, yang disebut antigen. Sebuah substansi yang kebanyakan orang mentolerir dengan baik, tetapi untuk alergen yang lain memiliki respon alergi, disebut alergen. Ketika antibodi IgE mengikat dengan alergen, mereka menyebabkan sel mast untuk melepaskan histamin dan bahan kimia lainnya, yang tumpah ke sel berdekatan.

Interaksi bahan kimia dengan reseptor pada permukaan pembuluh darah menyebabkan pembuluh cairan bocor ke jaringan sekitarnya, menyebabkan akumulasi cairan, kemerahan, dan bengkak. Pada sel-sel otot polos saluran pernafasan dan sistem pencernaan, mereka menyebabkan penyempitan. Pada ujung saraf, mereka meningkatkan sensitivitas dan menimbulkan rasa gatal.

Dalam anafilaksis, respon yang dramatis adalah karena hipersensitivitas ekstrim terhadap alergen dan distribusi biasanya sistemik. Allergen lebih mungkin menyebabkan anafilaksis jika mereka dimasukkan langsung ke dalam sistem peredaran darah melalui suntikan.

Namun, paparan oleh konsumsi, inhalasi, atau kontak dengan kulit juga bisa menyebabkan anafilaksis. Dalam beberapa kasus, anafilaksis dapat berkembang dari waktu ke waktu dari alergi kurang parah. Anafilaksis yang paling sering disebabkan oleh alergen dalam makanan, obat-obatan, dan racun serangga. Penyebab spesifik termasuk:

• Ikan, kerang, dan moluska• Kacang-kacangan dan biji-bijian• Sengatan lebah, tawon, atau hornet• Papain dari pelunak daging• Vaksin, termasuk vaksin flu dan campak• Penicilin

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• Cephalosporins• Streptomisin• Gamma globulin• Insulin• Hormon (ACTH, thyroid-stimulating hormone)• Aspirin dan NSAID lainnya• Lateks, dari pemeriksaan sarung tangan atau kondom, misalnya.

gejalaGejala mungkin termasuk:- Urtikaria (hives=penyakit gatal bintik merah dan bengkak)- Pembengkakan dan iritasi lidah atau mulut- Pembengkakan sinus- Kesulitan bernapas- mengi- Kram, muntah, atau diare- Kecemasan atau kebingungan- detak jantung Kuat, yang sangat cepat (palpitasi)- Kehilangan kesadaranTidak semua gejala akan timbul

diagnosaAnafilaksis didiagnosis berdasarkan perkembangan pesat dari gejala dalam merespon alergen

dicurigai. Identifikasi penyebabnya dapat dilakukan dengan pengujian RAST, tes darah yang mengidentifikasi reaksi IgE terhadap alergen tertentu. Tes kulit dapat dilakukan untuk reaksi anaphylatic kurang parah.

Anafilaksis adalah, akut berpotensi mematikan, sindrom multisistem dihasilkan dari pelepasan tiba-tiba sel mast dan basofil yang diturunkan mediator ke dalam sirkulasi. Ini paling sering hasil dari reaksi immulogic terhadap makanan, obat-obatan, dan sengatan serangga, meskipun juga dapat diinduksi melalui mekanisme nonimmulogic oleh agen mampu menghasilkan degranulasi, tiba-tiba sistemik dari sel mast atau basofil.

The phenomenen anafilaksis pertama kali dijelaskan dalam lirerature medis modern pada tahun 1902 dalam sebuah studi yang melibatkan protokol untuk mengimunisasi anjing dengan racun ubur-ubur. Injeksi sejumlah kecil toksin pada beberapa hewan, bukan perlindungan menghasilkan, diendapkan onset yang cepat gejala yang fatal atau dekat-fatal. Para penulis bernama respon "1'anaphylaxie," yang berasal dari berasal dari kata Yunani a-(melawan) dan phylaxis (kekebalan atau perlindungan).

Anafilaksis adalah jenis, sistemik I reaksi hipersensitivitas yang sering berakibat fatal. Anafilaksis memiliki berbagai penyebab, termasuk makanan, lateks, obat-obatan, dan racun hymenoptera. Epinefrin diberikan awal adalah intervensi yang paling penting. Pengobatan ajuvan injclude terapi cairan, H (1) anjd H (2) antagonis reseptor histamin, kortikosteroid, dan bronkodilator, namun ini tidak menggantikan epinefrin. Pasien dengan hystory anafilaksis harus dididik tentang kondisi mereka, terutama berkenaan dengan memicu penghindaran dan dalam penggunaan yang benar dari kit epinefrin autoinjector. Kit tersebut harus tersedia bagi pasien peka setiap saat.

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Anafilaksis adalah reation hipersensitivitas akut fatal atau fatal. Anafilaksis merupakan diagnosis klinis berdasarkan pada sejarah dan pemeriksaan fisik dan termasuk gejala obstruksi jalan napas, reaksi kulit umum, terutama memerah, gatal, urtikaria, angioedema gejala kardiovaskular termasuk gejala hipotensi dan gastrointestinal. Ini hasil Gejala dari tindakan mediator sel mast, terutama histamin dan mediator lipid seperti leukotriens dan faktor activiting plaelet pada jaringan shock. Jaringan kejutan meliputi pembuluh darah, kelenjar lendir, otot polos, dan ujung saraf.

Anafilaksis mengikuti kursus hypersensitity waktu yang khas langsung, dengan awal reaksi dalam beberapa menit pemaparan antigen. Beberapa jam reaksi akhir-fase setelah reaksi awal dapat terjadi. Sel mast pelepasan mediator dapat dipicu oleh kedua IgE dan non-IgE faktor dimediasi. Oleh karena itu, anafilaksis dapat disebut anphylaxis (IgE mediated) atau anaphylactoid (non-IgE mediated). IgE yang paling umum pemicu dimediasi adalah obat, biasanya penisilin atau beta-laktam antibiotik, makanan, paling sering kacang, kacang, ikan dan kerang, atau sengatan hymenoptera. Non-IgE penyebab dimediasi termasuk faktor yang menyebabkan aktivasi komplemen ditandai seperti protein plasma atau senyawa yang bertindak atas membran sel mast, seperti vankomisin, antibiotik kuinolon, atau media kontras radiografi. Patofisiologi beberapa faktor pemicu, aspirin seperti kita, masih belum jelas.

Terapi anafilaksis berkisar edukasi pasien, menghindari, desensitisasi atau pretreatment farmakologis ketika agen penyebab anafilaksis perlu readministered, dan pengenalan dini dan terapi cepat reaksi yang mungkin terjadi.

Reaksi hipersensitivitas IgE-dependent dan IgE-independen, yang kedua karena fisik, rangsangan kimia atau hiperosmolar, dapat berkembang sebagai anafilaksis atau reaksi anaphylactoid, oleh rilis meningkatnya mediator dari sel mast dan basofil. Tanpa pengobatan immediete, anafilaksis sejalan dengan morbiditas substansial (shock, kegagalan organ multiple) dan kematian, dalam beberapa menit ini respons klinis peledak bisa berakibat fatal. Tingkat keparahan anafilaksis / anaphylactoid reaksi dinilai dari 0 sampai tahap IV dalam rangka untuk memandu pengelolaan penyakit ini, tahap III sesuai dengan syok anafilaksis. Parah reaksi anafilaksis dapat mengambil kursus progresif meskipun terapi yang memadai, bahkan dalam kasus respon yang menguntungkan awal untuk tindakan pengobatan hidup trheatening gejala bisa kambuh, mungkin ada akhir-fase reaksi 6 sampai 12 jam setelah reaksi awal.

Untuk manajemen darurat awal pembedaan antara dimediasi IgE dan reaksi anafilaktoid IgE independen tidak diperlukan. Ini adalah prinsip-prinsip yang bersangkutan terapi pada pasien hipotensi dan hipoksia: penghapusan agen berbahaya kemungkinan di lokasi pengenalan, penyediaan jalan napas pasien, suplementasi oksigen 100%, terapi cairan intravena dan dukungan phamacological dengan katekolamin. Setelah perawatan primer pemantauan dan terapi pasien dengan syok anafilaksis harus dilanjutkan pada unit perawatan intensif. Guideliness untuk anafilaksis af manajemen akut mengacu pada kedua tahap penyakit, termasuk shock dan manifestasi klinis utama (kulit, pulmonay, kardiovaskular) telah dibentuk oleh sebuah konferensi konsensus Jerman interdisipliner dan diterbitkan pada tahun 1994, guideliness konsensus untuk perawatan medis darurat telah dikomunikasikan oleh ILCOR (1997) dan tim proyek dari Dewan Resuscitation (Inggris) (1999).

Shock (shok)1. Sebuah gangguan tiba-tiba keseimbangan mental

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2. Sebuah hemodinamik mendalam dan gangguan metabolisme akibat kegagalan sistem sirkulasi untuk mempertahankan perfusi memadai organ vital.