Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0000727 (
acute abdomen
)
3,084
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Anaphylaxis is a term that implies symptoms that are present in many organs, some of which are potentially fatal. The pathogenic process can either be IgE-dependent or non-IgE-dependent; the latter circumstance may be referred to as anaphylactoid.
Bradykinin
is frequently responsible for the manifestations of IgE-independent reactions. Blood levels may increase because of overproduction; diseases such as the various forms of C1 inhibitor deficiency (hereditary or acquired) or hereditary angioedema with normal C1 inhibitor are examples in this category. Blood levels may also increase because of an abnormality in
bradykinin
metabolism; the angioedema due to ACE inhibitors is a commonly encountered example. Angioedema due to
bradykinin
has the potential to cause airway obstruction and asphyxia as well as severe gastrointestinal symptoms simulating an
acute abdomen
. Formation of
bradykinin
in plasma is a result of a complex interaction among proteins such as factor XII, prekallikrein, and high molecular weight
kininogen
(HK) resulting in HK cleavage and liberation of
bradykinin
. These proteins also assemble along the surface of endothelial cells via zinc-dependent interactions with gC1qR, cytokeratin 1, and u-PAR. Endothelial cell expression (or secretion) of heat-shock protein 90 or prolylcarboxypeptidase can activate the prekallikrein-HK complex to generate
bradykinin
in the absence of factor XII, however factor XII is then secondarily activated by the kallikrein that results.
Bradykinin
is destroyed by carboxypeptidase N and angiotensin-converting enzyme. The hypotension associated with IgE-dependent anaphylaxis maybe mediated, in part, by massive proteolytic digestion of HK by kallikreins (tissue or plasma-derived) or other cell-derived kininogenases.
...
PMID:Kinins, airway obstruction, and anaphylaxis. 2051 82
Angioedema is a self-limiting edema of the subcutaneous or submucosal tissues due to localised increase of microvascular permeability whose mediator may be histamine or
bradykinin
. Patients present to emergency department when angioedema involves oral cavity and larynx (life-threatening conditions) or gut (mimicking an
acute abdomen
). After initial evaluation of consciousness and vital signs to manage breathing and to support circulation if necessary, a simple approach can be applied for a correct diagnosis and treatment. Forms of edema such as anasarca, myxedema, superior vena cava syndrome and acute dermatitis should be ruled out. Then, effort should be done to differentiate histaminergic from non-histaminergic angioedema. Concomitant urticaria and pruritus suggest a histaminergic origin. Exposure to allergens and drugs (mainly ACE inhibitors and non steroidal anti-inflammatory drugs) should be investigated as well as a family history of similar symptoms. Allergic histaminergic angioedema has a rapid course (minutes) whereas non histaminergic angioedema is slower (hours). Since frequently the intervention needs to be immediate, the initial diagnosis is only clinical. However, laboratory tests can be subsequently confirmatory. Allergic angioedema is sensitive to standard therapies such as epinephrine, glucocorticoids and antihistamines whereas non histaminergic angioedema is often resistant to these drugs. Therapeutic options for angioedema due C1-inhibitor deficiencies are C1-inhibitor concentrates, icatibant and ecallantide. If these drugs are not available, fresh frozen plasma can be considered. All these medications have been used also in ACE inhibitor-induced angioedema with variable results thus they are not currently recommended whereas experts agree on the discontinuation of the causative drug.
...
PMID:Angioedema and emergency medicine: From pathophysiology to diagnosis and treatment. 3022 Apr 53