Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presentation, evolution, and treatment of two cases of intraoperative allergic reactions are described. In each case, the offending agent was felt to be hydroxyethyl starch (HES), a synthetic polymer colloid solution used for intravascular volume expansion. Symptoms included urticaria, angioedema, and hypotension in the first patient, and urticaria, hypoxia, and haemoconcentration in the second patient. Both patients had earlier received multiple drugs and/or blood products. However, HES administration in both patients immediately produced allergic symptomatology. The first patient had concurrent depression of serum total complement levels (CH50) and no elevation of plasma histamine levels, which suggested a complement-mediated reaction to HES. Levels of CH50 and histamine were not obtained from the second patient. Direct stimulation of mast cell degranulation by the offending agent, complement activation, or conventional antigen-antibody interaction in a previously exposed patient may initiate intraoperative allergic reactions. Anaesthesia personnel should be aware of the risk of intraoperative allergic reactions to HES and be prepared to treat them rapidly and effectively.
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PMID:Intraoperative allergic reactions to hydroxyethyl starch: a report of two cases. 242 78

Prostaglandin (PG) D2 and histamine concentrations have been measured in blood draining cold-challenged forearm skin in patients with cold urticaria. Local venous concentrations of both histamine and PGD2 rose in four patients who developed a whealing response. Plasma histamine concentration increased from a mean resting value of 0.24 +/- 0.09 (SD) ng/ml to peak values of 16.9 to 96.6 ng/ml. Resting concentrations of PGD2 were below the limit of detection (5 pg/ml) in three patients and 62 and 27 pg/ml in the fourth. Peak plasma PGD2 concentration after challenge ranged from 166 to 279 pg/ml. Time course of histamine and PGD2 release was similar with peak concentrations at 6 and 10 minutes, respectively. The maximum clinical response occurred between 10 and 20 minutes after challenge. Our findings demonstrate that PGD2 is produced in association with mast cell degranulation in man, but the amount, relative to histamine, is low. Despite its high potency in production of inflammatory effects, PGD2 probably has only minor direct effects in cold urticaria, although it may act to potentiate other mediators.
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PMID:Prostaglandin D2 and histamine release in cold urticaria. 242 56

A case of localized heat urticaria in a 70-year-old woman is reported. Increased plasma levels of prostaglandin D2 and blood histamine after heat challenge indicate a role for mast cell degranulation in the pathophysiology of the syndrome. Treatment with astemizole increased the temperature threshold to wealing, but not to itch or erythema. The patient was partially desensitized by repeated exposure to heat and this was further improved by indomethacin. After treatment there was no increase in plasma prostaglandin D2 on challenge. No evidence was found for the activation of the alternative complement pathway.
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PMID:Release of prostaglandin D2 and histamine in a case of localized heat urticaria, and effect of treatments. 243 16

The porphyrias are the only group of diseases caused by endogenous phototoxic agents. While patients with erythropoietic protoporphyria and those with porphyria cutanea tarda both have skin lesions on sun-exposed areas, there are differences in their cutaneous manifestations. Based on information discussed in this chapter, the following pathophysiologic mechanisms can be proposed. In porphyria cutanea tarda, photoactivation of the complement system in the presence of uroporphyrin results in activation of dermal mast cells, which release their proteases. This results in dermal-epidermal separation, reflected clinically as skin fragility and vesicles. The interaction between activated mast cells with fibroblasts, the nature of which is still unclear, may contribute to fibrosis and sclerodermoid skin changes. The stimulatory effect of uroporphyrin on collagen biosynthesis by fibroblasts, which occurs independent of irradiation, may be responsible for the sclerodermoid lesions seen at sun-exposed as well as sun-protected areas. In erythropoietic protoporphyria, mast cell activation can occur as the result of complement activation induced by protoporphyrin and irradiation. Protoporphyrin and irradiation may also directly induce the release of preformed and generated mediators from mast cells, a process mediated at least in part by peroxidation. The release of mast cell mediators may account for the erythema, edema, and urticaria observed in patients with erythropoietic protoporphyria upon exposure to sunlight. Interaction of mast cells with fibroblasts, and the direct membrane-damaging effect of protoporphyrin and irradiation on the latter, may contribute to the waxy thickening of skin seen in chronically sun-exposed areas of these patients. There are, however, many unanswered questions. What accounts for the different biological effects of mast cell-derived mediators: dermal-epidermal separation in one, erythema and urticaria in the other? The fragmentation of dermal collagen bundles associated with cleavage beneath the lamina densa, and the hyperpigmentation and hypertrichosis observed in some patients with porphyria cutanea tarda remain unexplained. What is the mechanism of the reduplication of blood vessel basal lamina in the non-sun-exposed areas of both types of patient? Are there any roles for cytokines and epidermal cell-derived eicosanoids? While it is clear that the pathogenesis of cutaneous lesions in porphyria cutanea tarda and erythropoietic protoporphyria involves interactions among inflammatory mediators and various cells in skin, much still needs to be done to further our understanding of their pathophysiology.
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PMID:Mechanisms of phototoxicity in porphyria cutanea tarda and erythropoietic protoporphyria. 248 74

We report the investigation and treatment of a 28-year-old woman with the rare condition of non-familial vibratory angiodema. Lesions were reproduced using a vibrator set at pre-determined frequencies and amplitudes, applied for a fixed time period. There was no indication of the production of tolerance in the patient with repeated vibration, but terfenadine produced a good therapeutic response. There was no evidence of mast cell degranulation at the ultrastructural level. The patient also had mild delayed pressure urticaria and dermographism, thus demonstrating the clustering frequently found in the physical urticarias.
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PMID:Vibratory angioedema: lesion induction, clinical features, laboratory and ultrastructural findings and response to therapy. 257 34

Four patients with cholinergic urticaria associated with additional cardiorespiratory manifestations are described. Two patients reported cold, in addition to heat and exercise, as a factor inducing symptoms. Prospective exercise challenge documented a rise in in plasma histamine sixfold to 20-fold above baseline values that accompanied onset of symptoms. All four subjects had proved refractory to conventional antihistamine therapy. Institution of ketotifen at doses ranging from 3 to 8 mg per day resulted in symptomatic improvement, and in all four subjects a repeat exercise challenge confirmed clinical improvement. In three subjects exercise challenge with ketotifen demonstrated blockade of mast cell-mediator release. Plasma histamine levels remained at baseline. In the fourth patient, histamine rose to about half the peak observed before ketotifen therapy. These findings confirm the observation that ketotifen is both an H1 histamine-receptor antagonist as well as a stabilizer of mast cell-mediator release. We speculate that ketotifen may prove more effective than conventional antihistamines in the management of severe urticaria.
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PMID:Refractory cholinergic urticaria successfully treated with ketotifen. 237 Mar 85

The abundance of mast cells in human dermis, together with their ability to release a variety of vasoactive and pro-inflammatory mediators following cross-linkage of their cell-surface receptors for IgE, enables these cells to provide an effective defence mechanism within this organ. A similar defensive function is attributed to mast cells of other human organs such as intestine and lung which are in contact with the external environment and therefore susceptible to infiltration by foreign allergens and micro-organisms. However, mast cells of the skin apparently differ from those present in lung and intestine in being activated for histamine release by a variety of endogenous neuropeptides which stimulate the rapid release of histamine in the virtual absence of eicosanoids. This would provide a mechanism of neurogenic control of a variety of homeostatic functions such as blood flow, angiogenesis and fibroblast proliferation. Such processes would aid in the remodelling of tissue during wound healing, and increased numbers of mast cells have been noted around healing wounds of rat skin and areas of developing fibrosis. Neuropeptides modulate the activity of a variety of immuno-competent leucocytes including macrophages, monocytes and lymphocytes. The findings that skin mast cells are activated by neuropeptides suggest that these cells may also be included amongst those involved in neuro-immune interactions. Activation of skin mast cells by non-immunological stimuli may contribute to the aetiology of some forms of skin disease. Patients with chronic idiopathic urticaria appear to have enhanced vascular responsiveness to intradermal injections of the histamine liberator codeine suggesting that this disease may involve hyper-responsiveness of their mast cells to endogenous non-immunological stimuli. The findings of large increases in histamine accompanied by small increases in PGD2 in venous effluent of thermally challenged limbs of patients with cold- or heat-induced urticaria may suggest that their mast cells had been activated by a non-immunological stimulus. However, the interpretation of results gained using such relatively complex in-vivo systems are difficult, as the cellular origin of the detected mediators is by no means clear. However, it is hoped that in the future the alliance of newly developed in-vitro techniques to investigate mast cell function together with in-vivo methods to investigate their interaction with elements in their tissue environment will greatly increase our understanding of the role of the human skin mast cell in health and disease.
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PMID:The human skin mast cell. 266 2

Two patients with local heat urticaria were examined for evidence of histamine release and for changes in mast cell morphology after local heat challenge. Both patients demonstrated significant release of histamine into the draining venous blood in the challenged arm. Biopsy specimens revealed mucosal edema after 30 min, followed by a mononuclear, perivascular infiltrate by 6 hr, and increasing in intensity by 24 hr. Degranulated mast cells were observed by electron microscopy. Heat challenge was repeated after treatment with hydroxyzine, cimetidine, or a combination of both drugs. Neither hydroxyzine nor cimetidine alone affected the clinical response to challenge, but both drugs together completely abolished the clinical response. In addition, the combination of both drugs taken regularly completely prevented symptoms. This observation suggests that histamine is one of the major mediators of this disorder and that both H1 and H2 receptors are operative.
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PMID:Mediator release in local heat urticaria: protection with combined H1 and H2 antagonists. 286 Dec 21

Mastocytosis is a disease characterized by an increase in the number of tissue mast cells and a concomitant increase in mast cell-derived mediators. To demonstrate the spectrum of skin disease in mastocytosis in the pediatric population, five children with mastocytosis and complaints of urticaria (4/5), bullae/vesicles (3/5), abdominal pain (3/5), flushing (2/5), headache (1/5), and bone pain (1/5) are reviewed. Confirmation of the diagnosis of cutaneous mastocytosis was obtained by histologic examination of a biopsy of lesional skin; however, mast cell numbers in lesional skin did not correlate with plasma histamine levels or the extent of cutaneous involvement. Mastocytosis is a diagnosis that must be recognized in the differential diagnosis of pediatric urticarial diseases.
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PMID:Mastocytosis in infants and children: recognition of patterns of skin disease. 292 86

Sixteen patients with chronic idiopathic urticaria were skin tested with their own serum, IO with autologous plasma and five with serum that had been heated to 56 degrees C to inactivate complement. Eight showed a weal and flare response to whole serum, four to plasma and five to heat-treated serum. All serum-positive patients showed the same response to their own plasma and to heated serum, indicating that the mediator concerned is not generated by clotting and is not dependent on a functioning complement pathway. Three control subjects were negative to autologous serum, plasma and heated serum. Local tachyphylaxis was demonstrated in five serum-positive patients on reinjection of the same site with autologous serum on 3 consecutive days. This raises the possibility that the serological mediator may be acting by mast cell degranulation or directly on receptors in blood vessels and that repeated injections could induce a change in the number of receptors. Passage of whole autologous serum from four serum-positive patients through ultrafiltration membranes showed that fractions with a molecular weight of less than 30,000 daltons were still able to produce a positive skin test response, but those less than 1000 daltons were not. All serum fractions from two serum-negative patients and three normal controls were negative. Whole autologous serum from five serum-positive patients and two control subjects were separated by column chromatography. On skin testing with pooled fractions, the greatest response was produced by fractions of 10,000-15,000 daltons in the serum-positive patients, but there was no response in the controls.
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PMID:Preliminary identification of a low molecular weight serological mediator in chronic idiopathic urticaria. 316 39


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