Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042109 (urticaria)
 6,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiotensin-converting enzyme (ACE) inhibitor associated angioedema was detected in 39 subjects (17%) of 231 consecutive patients examined in the last 5 years at our out-patient clinic for symptoms of angioedema without urticaria. In these patients, angioedema was most commonly localized to the face. The duration of ACE-inhibitor treatment at the onset of angioedema ranged from 1 day to 8 years with a median of 6 months. The time elapsed between onset of angioedema and withdrawal of ACE-inhibitor ranged from 1 day to 10 years with a median of 10 months. Delayed diagnosis is explained by the unusual characteristics of this adverse reaction: angioedema may start years after beginning the treatment and then it recurs irregularly. In fact, ACE-inhibitors seem to facilitate angioedema in predisposed subjects, rather than causing it with an allergic or idiosyncratic mechanism. Thus, while Cl-inhibitor levels are usually normal in subjects developing ACE-inhibitor-dependent angioedema, we found that ACE-inhibitors caused angioedema in Cl-inhibitor-deficient patients. Because the main inactivator of bradykinin is kininase II, which is identical with ACE, it is believed that bradykinin mediates ACE-inhibitor-dependent angioedema. We had the possibility to examine the plasma bradykinin levels in one ACE-inhibitor-treated patient during an angioedema attack and we found very high levels, but we did not find an increase of break-down products of high-molecular-weight-kininogen as observed during acute attacks in hereditary angioedema. Bradykinin fell to normal levels during remission after withdrawal of the drug. These observations indicate that in ACE-inhibitor-induced angioedema, contrary to hereditary angioedema, the reduction of bradykinin catabolic rate plays a predominant role.
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PMID:Angioedema due to angiotensin-converting enzyme inhibitors. 1060 20

Urticaria is a classic cutaneous manifestation of drug allergy considered like the second most frequent drug eruption after maculopapular exanthemas. Most of the time drugs are responsible of acute urticaria lasting less than 24 hours. The mechanisms of these acute urticarial reactions are multiple, mostly related to an IgE-induced reaction. Nevertheless, some drugs can induce immune complexes and activate the complement cascade (sickness disease). Others may directly release mast cells mediators or activate complement by non immunologic mechanisms in the absence of antibody. In every case, these drugs are unable to generate urticaria during more than 6 weeks, time allowed for calling a chronic urticaria. However drugs like nonsteroidal anti-inflammatory drugs and acetysalicylic acid can, by a pharmacologic mechanism, exacerbate or trigger chronic urticaria. Angiotensin-converting enzyme inhibitors, by a defect of degradation of bradykinin, may also induced angioedemas. In this context, if an allergologic investigation is useful in the exploration of acute urticaria, it seems useless for chronic urticaria.
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PMID:[Drug-induced chronic urticarias]. 1284 7

Urticaria and angioedema are common allergic manifestations and medications are one of common triggering factors. The most severe immediate drug reaction is anaphylaxis. Apart from the well established IgE-mediated immediate type hypersensitivity reactions, the pathogenesis of drug-induced urticaria, angioedema and anaphylaxis often remains obscure. In this article, emphasis is put on nonallergic reactions to the most commonly used drug groups of nonsteroidal antiinflammatory drugs, angiotensin-converting enzyme inhibitors, radiocontrast media, volume expanders and drugs used in general anesthesia. Urticaria is the second most common drug eruption after maculopapular exanthema. The mechanisms of acute urticarial reactions are multiple, mostly IgE mediated, but some drugs can induce immune complex reactions and activate complement cascade, while others can induce direct activation of mast cells and degranulation or activation of complement by non-immune mechanisms. With different types of medications different pathomechanisms are involved. Non-steroid anti-inflammatory drugs are thought to cause reaction due to cyclooxygenase-1 inhibition and overproduction of leukotrienes, blamed for cutaneous and respiratory symptoms. Angiotensin-converting enzyme inhibitors can cause fatal angioedema, which is partially explained with bradykinin excess and impairment of aminopeptidase P and dipeptidyl peptidase IV that are involved in the metabolism of substance P and bradykinin. It remains unknown what additional mechanisms are involved. Radiocontrast media and local anesthetics mostly cause nonallergic hypersensitivity reaction, but in rare cases true allergic reaction can occur. Dextran is known to cause IgG mediated, immune complex anaphylaxis and it is recommended to use human serum albumin as the safest colloid.
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PMID:Nonallergic hypersensitivity to nonsteroidal antiinflammatory drugs, angiotensin-converting enzyme inhibitors, radiocontrast media, local anesthetics, volume substitutes and medications used in general anesthesia. 1938 16

Angiotensin-converting enzyme inhibitors (ACEIs) represent an important group of pharmacological compounds, largely prescribed for more than 30 years. They have been extensively evaluated in clinical trials, demonstrating significant reduction of morbidity and mortality of patients with cardiovascular diseases, mainly high blood pressure, myocardial infarction, heart failure and stroke. Besides their beneficial effects and a general good safety profile, it was proven that ACEIs might also induce adverse effects in some patients, most notably angioedema (AE) and chronic cough. The occurrence rate of adverse events induced by ACEIs is low, but the number of suffering patients is relatively high, since ACEIs is one of the most frequently prescribed medication worldwide. The aim of our study was to evaluate clinical pattern, risk factors and general management of ACEI-induced angioedema in a cohort of patients addressed for allergist evaluation in one university hospital in Romania, during a period of 32 months. It was found that ACEI-induced angioedema (ACEI-AE) represented more than half of the total number of patients addressed for angioedema without urticaria, with variable clinical and time-patterns. Most of the patients were referred by general practitioners (GPs) with diagnosis of urticaria or other skin allergy and continued to take ACEIs for months and years after onset of angioedema. We concluded that the awareness of acquired, non-allergic angioedema induced by ACEI therapy in medical practice is still low and there is a need for improved knowledge and interdisciplinary collaboration in this field.
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PMID:Acquired angioedema induced by angiotensin-converting enzyme inhibitors - experience of a hospital-based allergy center. 3250 96