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)

Mastocytosis comprises several diseases characterized by an abnormal increase in tissue mast cells. Cutaneous mastocytosis (CM) is the most common form of mastocytosis, affects predominantly children, and presents as a mast cell hyperplasia limited to the skin. Systemic mastocytosis (SM) comprises multiple distinct entities in which mast cells in filtrate the skin and/or other organs. The diagnosis of SM is based on the presence of one major criterion and one minor criterion or three minor criteria. Major criteria include the presence of multifocal dense infiltrates of > 15 mast cells in bone marrow and/or other extracutaneous organs. Four minor criteria include the presence of elevated serum alpha-tryptase levels > 20 ng/mL, the expression of CD2 and CD25 surface markers in c-kit-positive mast cells from bone marrow or other organs, the presence of a c-kit mutations on bone marrow and/or other tissues mast cells, and the presence of > 25% abnormal spindle-shaped mast cells in bone marrow and/or tissues. Symptoms of CM include pruritus, flushing urticaria, and dermatographism. Symptoms of SM include cutaneous symptoms in association with syncope, gastric distress, nausea and vomiting, diarrhea, bone pain, and neuropsychiatric symptoms. Activating and nonactivating mutations of c-kit (Asp816Val) are seen in adult SM and in some pediatric CM (Gly839Lys), indicating a clonal dysregulation. There is no cure for mastocytosis but the majority of pediatric CM regress at puberty. Women with mastocytosis are fertile and pregnancy and delivery have been successful by blocking mast cell-mediated symptoms. Symptomatic treatment aimed at reducing the effect of mediators is effective with antihistamines and mast cell-stabilizing agents such as sodium cromolyn. To reduce mast cell burden, interferon alpha, steroids, and purine analogs have been used with varying results. Future directions include tyrosine kinase inhibitors and bone marrow transplant.
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PMID:Mastocytosis: classification, diagnosis, and clinical presentation. 1505 60

Systemic mastocytosis (SM), as opposed to cutaneous-only mastocytosis, implies the presence of neoplastic mast cell infiltration in extracutaneous tissue. Mast cell disease in adults is often systemic and often involves the bone marrow. Typical clinical and laboratory features of SM include urticaria pigmentosa, mast cell mediator symptoms (eg, headache, flushing, lightheadedness, urticaria and pruritus, nausea, diarrhea, abdominal pain, and vasodilatory shock), bone pain (eg, osteoporosis, lytic bone lesions, and fractures), hepatosplenomegaly, cytopenia, eosinophilia, elevated serum tryptase and histamine, and bone marrow fibrosis and angiogenesis. SM may be indolent (no evidence of organ dysfunction), aggressive (presence of organ dysfunction), associated with another often chronic myeloid hematologic disease (SM-AHD), or present as mast cell leukemia or sarcoma. Mast cell-mediator symptoms are treated with histamine antagonists and cromolyn sodium. Indolent SM does not require cytoreductive therapy. Aggressive SM and SM-AHD are managed based on their molecular profile. Recent information suggests that FIP1-like-1-platelet-derived growth factor receptor-alpha(+) SM responds well to imatinib mesylate, whereas interferon-alpha should be considered as a first-line treatment in all of the other cases, including patients with Asp816Val(+) SM. Cladribine has been shown to be effective in patients who develop resistance to interferon treatment.
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PMID:Systemic mastocytosis: current concepts and treatment advances. 1508 68

Systemic mastocytosis (SM) results from clonal, neoplastic proliferation of abnormal mast cells. Patients become susceptible to itching, urticaria, and anaphylactic shock, which occurs due to histamine release from mast cells. SM may coexist alongside other systemic diseases, thus confounding the overall clinical presentation. We discuss a 23-year-old woman with refractory pruritus, which was initially attributed to primary sclerosing cholangitis but had a nonresponse to antihistaminics, ursodiol, and cholestyramine. Concurrent evaluation for polyarthritis revealed increased uptake in the proximal femur on a bone scan, and subsequent bone marrow biopsy revealed indolent SM, and this was understood to be the cause of her intractable pruritus.
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PMID:Systemic Mastocytosis Causing Refractory Pruritus in a Liver Disease Patient. 2792 Oct 51

Hymenoptera venom allergy ranks among the top three causes of anaphylaxis worldwide, and approximately one-quarter of sting-induced reactions are classified as severe. Fatal sting reactions are exceedingly rare, but certain factors may entail a considerably higher risk. Delayed administration of epinephrine and upright posture are situational risk factors which may determine an unfavorable outcome of the acute anaphylactic episode and should be addressed during individual patient education. Systemic mastocytosis and senior age are major, unmodifiable long-term risk factors and thus reinforce the indication for venom immunotherapy. Vespid venom allergy and male sex likewise augment the risk of severe or even fatal reactions. Further studies are required to assess the impact of specific cardiovascular comorbidities. Available data regarding potential effects of beta-blockers and/or ACE inhibitors in coexisting venom allergy are inconclusive and do not justify recommendations to discontinue guideline-directed antihypertensive treatment. The absence of urticaria/angioedema during sting-induced anaphylaxis is indicative of a severe reaction, serum tryptase elevation, and mast cell clonality. Determination of basal serum tryptase levels is an established diagnostic tool for risk assessment in Hymenoptera venom-allergic patients. Measurement of platelet-activating factor acetylhydrolase activity represents a complementary approach but is not available for routine diagnostic use.
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PMID:Risk factors and indicators of severe systemic insect sting reactions. 3119 89