causal drugs<\/span>.<\/p>\nThe most common drugs to cause this reaction are a number of antiepileptic drugs (particularly carbamazepine, phenobarbital, and phenytoin), the anti-gout drug, allopurinol, olanzapine, and the sulfonamide group of antibiotics. It has been estimated that at least 1 in 10,000 patients treated with an anticonvulsant will develop drug hypersensitivity syndrome.<\/p>\n
The risk of drug hypersensitivity syndrome in patients with allopurinol depends on the dose of allopurinol. It is higher if the patient has kidney disease and is also taking thiazide diuretics.<\/p>\n
It has also been rarely reported to be due to other medications. It can be very difficult to determine the exact cause of drug hypersensitivity syndrome if multiple medications have been started in the past weeks. In approximately 10% of cases, the causal drug<\/span> never identifies<\/p>\n\n
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<\/span>What causes drug hypersensitivity syndrome?<\/span><\/h2>\nDrug hypersensitivity syndrome is a delay T cell<\/span>-mediated reaction. Tissue damage is due to cytotoxic<\/span> T cells<\/span> and cytokine<\/span> launching.<\/p>\n\n- There's a genetic predisposition<\/span><\/span> to drug hypersensitivity syndrome.<\/li>\n
- A defect in the way the liver metabolizes drugs may be responsible.<\/li>\n
- Reactivation of human herpes virus 6 (HHV6, the cause of roseola) or Epstein Barr virus (EBV) may also be important.<\/li>\n<\/ul>\n
<\/span>What are the clinical features of drug hypersensitivity syndrome?<\/span><\/h2>\nDrug hypersensitivity syndrome usually develops over several days, with onset between 2 and 8 weeks after starting the responsible drug.<\/p>\n
Usually a high fever of 38\u201340 C is first noted. This is quickly followed by a extended<\/span> skin eruption<\/span>. The characteristics of the eruption are diverse.<\/p>\n\n- \n
Morbilliform eruption affects 80% of cases, with different morphology<\/span> even targettoid<\/span> lesions, blisters and pustules<\/span>\n<\/li>\n- \nErythroderma<\/span> or exfoliative dermatitis<\/span> (involving> 90% of body surface area) can follow at about 10%<\/li>\n
- Facial swelling affects 30%.<\/li>\n
- \nMucous membrane<\/span> involvement affects 25% (lips, mouth, throat, genitals)<\/li>\n<\/ul>\n
The rash can last for many weeks.<\/p>\n\n<\/span>Rash drug hypersensitivity syndrome<\/span><\/h5>\n<\/section>\n\n\n
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Drug eruption<\/p>\n
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Drug eruption<\/p>\n
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Drug eruption<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>Systemic compromise in drug hypersensitivity syndrome<\/span><\/h3>\nSymptoms may get worse after stopping the drug and can continue for weeks or even months despite drug withdrawal. The severity of the rash does not necessarily correlate with the degree of involvement of the internal organs. Later symptoms depend on the internal organs affected. They may include:<\/p>\n
\n- Enlarged lymph nodes<\/span> multi-site (75%)<\/li>\n
- Hematological disorders: elevated white count (or less commonly, reduced white count), eosinophilia (in 30% this is> 2.0 x 109 \/ L), atypical<\/span> lymphocytes<\/span>, thrombocytopenia<\/span>, anemia<\/span>, hemophagocytic syndrome<\/li>\n
- Enlargement of the liver, hepatitis<\/span> and rarely hepatic<\/span> necrosis<\/span> with liver failure Abnormal liver function tests are found in 70 to 90%<\/li>\n
- Kidney disease: affects approximately 10% and is usually mild (interstitial<\/span> nephritis<\/span>) Renal<\/span> failure is rare<\/li>\n
- Inflammation of the heart (myocarditis<\/span>) or cardiac sac (pericarditis<\/span>), which causes chest pain, dyspnea, and low blood pressure<\/li>\n
- Lung disease, causing shortness of breath and coughing (interstitial pneumonitis<\/span>, pleurisy, pneumonia and acute respiratory distress syndrome)<\/li>\n
- \nNeurological <\/span>participation, which can lead to meningitis<\/span> Y, encephalitis<\/span>, polyneuritis, which causes headache, seizures, coma, and paralysis<\/li>\n
- Gastrointestinal symptoms: stomach flu<\/span>, pancreatitis<\/span>, bleeding and dehydration. In severe, acute cases colitis<\/span> and pancreatitis may occur, and chronic<\/span> enteropathy may occur<\/li>\n
- \nEndocrine<\/span> abnormalities: thyroiditis and diabetes<\/li>\n
- Muscle diseasemyositis<\/span>)<\/li>\n
- Eye disease (uveitis<\/span>)<\/li>\n<\/ul>\n
<\/span>What are the complications of drug hypersensitivity syndrome?<\/span><\/h2>\nMortality from drug hypersensitivity syndrome is estimated to be around 8%. Causes of death include:<\/p>\n
\n- Acute liver failure causes coagulation<\/span> problems, jaundice<\/span> and altered consciousness<\/li>\n
- Multi-organic failure<\/li>\n
- Fulminant myocarditis<\/li>\n
- Hemophagocytosis<\/li>\n<\/ul>\n
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<\/span>How is drug hypersensitivity syndrome diagnosed?<\/span><\/h2>\nThe diagnosis of drug hypersensitivity syndrome is based on the clinical presentation of the triad of:<\/p>\n
\n- High fever<\/li>\n
- Extensive skin rash<\/li>\n
- Organ compromise<\/li>\n<\/ul>\n
It is supported by eosinophilia and abnormal liver function tests.<\/p>\n
As drug hypersensitivity syndrome can occur up to eight weeks after the first exposure to the responsible drug, a great deal of care is required in determining the responsible drug. A temporary<\/span> The association between the use of medications and the onset of the syndrome is the strongest evidence.<\/p>\nThe European Severe Skin Registry Adverse reactions<\/span> Drug and Biological Sample Collection (RegiSCAR) has produced diagnostic criteria to aid in the diagnosis of drug hypersensitivity syndrome. RegiSCAR's inclusion criteria for potential cases require at least 3 of the following:<\/p>\n\n- Hospitalization<\/li>\n
- Reaction suspected of being related to drugs<\/li>\n
- Acute skin rash<\/li>\n
- Fever above 38 C<\/li>\n
- Enlarged lymph nodes at two sites<\/li>\n
- Involvement of at least one internal organ<\/li>\n
- Blood count abnormalities such as low platelets<\/span>raised eosinophils<\/span> or abnormal lymphocyte<\/span> tell<\/li>\n<\/ul>\n
Attempts to confirm which drug has caused the drug hypersensitivity syndrome may include patch<\/span> testing Patch testing has been reported to be most successful for antiepileptic drugs, with a 50% of positive reactions. Not useful for allopurinol, with 0% of positive reactions. The lymphocyte transformation test is available in some centers, where specialized interpretation can reveal the offending drug in most cases.<\/p>\n<\/span>Research on drug hypersensitivity syndrome<\/span><\/h3>\nAfter taking a careful history and performing a general and skin exam, the following tests may be ordered.<\/p>\n
Skin biopsy<\/span> usually shows dense infiltration<\/span> of inflammatory<\/span> cells, including lymphocytes and eosinophils, extravasated<\/span> erythrocytes<\/span>and edema<\/span>.<\/p>\nBlood tests can include:<\/p>\n
\n- Blood count and coagulation studies<\/li>\n
- Biochemical tests: at least liver function, kidney function, muscle. enzymes<\/span>\n<\/li>\n
- Viral serology<\/span>: hepatitis B, C, EBV, CMV, HHV-6<\/li>\n
- Endocrine function: thyroid, glucose<\/span> levels<\/li>\n<\/ul>\n
A urinalysis is done to assess kidney damage.<\/p>\n
Cardiac and pulmonary<\/span> evaluation may include electrocardiograph (ECG), echocardiogram<\/span>and chest x-ray. Scans may be done to evaluate the liver, kidneys, and brain based on symptoms and the results of initial tests.<\/p>\n<\/span>What is the treatment for drug hypersensitivity syndrome?<\/span><\/h2>\nTreatment consists of immediate withdrawal of all suspected medications, followed by careful monitoring and supportive care. It is very important that patients with high fever and rash, where it is considered a diagnosis of drug hypersensitivity syndrome, have blood tests as soon as possible.<\/p>\n
Systemic steroids (eg, Prednisone) are generally used in the most severe cases of drug hypersensitivity syndrome involving significant exfoliative dermatitis, pneumonitis, and \/ or hepatitis. However, the benefits of corticosteroids are unknown as controlled clinical trials are lacking. Once effective, they must be withdrawn very slowly, as the syndrome may recur as the dose is reduced.<\/p>\n
Cyclosporine has been reported to be an effective alternative treatment for drug hypersensitivity syndrome.<\/p>\n
Additional treatment may include intravenous immunoglobulin<\/span>, plasmapheresis and immunomodulator<\/span> medications such as cyclophosphamide, mycophenolate, and rituximab.<\/p>\nSupportive treatment for the rash may include:<\/p>\n
\n- Dressings<\/li>\n
- Current<\/span> corticosteroids<\/li>\n
- Emollients<\/span><\/li>\n
- Oral antihistamines.<\/li>\n<\/ul>\n
Fluid, electrolyte, and calorie intake may need attention. A warm environment and skilled nursing care are required. Secondary infections may require antibiotics.<\/p>\n
<\/span>How can drug hypersensitivity syndrome be prevented?<\/span><\/h2>\nPatients who develop drug hypersensitivity syndrome should avoid taking the offending drugs again.<\/p>\n
Cross-reactions are common between the three main aromatic anticonvulsant medications (phenytoin, carbamazepine, and phenobarbitone), and patients who have experienced drug hypersensitivity syndrome with any of these medications should avoid all three.<\/p>\n
Because genetic factors are suspected in drug hypersensitivity syndrome, first-degree relatives should be alerted to their high risk of developing hypersensitivity reactions to the same drugs.<\/p>\n
<\/span>What is the prognosis for drug hypersensitivity syndrome?<\/span><\/h2>\nMost patients fully recover from drug hypersensitivity within weeks to months. Relapse<\/span> After the initial improvement it is common.<\/p>\nPatients recovering from drug hypersensitivity syndrome are believed to be at risk of developing autoimmune<\/span> diseases<\/p>\n<\/section>","protected":false},"excerpt":{"rendered":"\u00bfQu\u00e9 es la droga? hipersensibilidad s\u00edndrome? El s\u00edndrome de hipersensibilidad a medicamentos es una reacci\u00f3n grave e inesperada a un medicamento, que afecta varios sistemas de \u00f3rganos al mismo tiempo….<\/p>","protected":false},"author":8,"featured_media":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":{"footnotes":""},"categories":[204],"tags":[],"class_list":["post-7861","wiki","type-wiki","status-publish","format-standard","category-glosario-definiciones"],"_links":{"self":[{"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/wiki\/7861","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/wiki"}],"about":[{"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/types\/wiki"}],"author":[{"embeddable":true,"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/comments?post=7861"}],"version-history":[{"count":0,"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/wiki\/7861\/revisions"}],"wp:attachment":[{"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/media?parent=7861"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/categories?post=7861"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/doctorhoogstra.com\/en\/wp-json\/wp\/v2\/tags?post=7861"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}