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Query: UMLS:C0033774 (pruritus)
 14,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The characteristic temperature-dependent pruritus in polycythemia vera (PV) is described. The triggering factor seems to be a sudden decrease in skin temperature, e.g. after a hot bath or shower. The sudden onset and limited duration of the pruritus might suggest an activation or release of some humoral factor(s). In a controlled study we showed that aspirin alleviates this particular pruritus. Therefore, the possibility of prostaglandin and platelet involvement was considered. It was found that substances such as PGE2 and serotonin, produced and released by platelets, could elicit pruritus in healthy volunteers when injected intradermally and that PGE2 enhanced the cutaneous responses to serotonin. Studies of platelet aggregation did not reveal any abnormalitites in the PV patients but ADP was shown to sensitize platelets to adrenaline-induced aggregation in vitro. Although not proven the following hypothesis is suggested: a combination of ADP, emerging from erythrocytes, and catecholamines released from adrenergic vasoconstrictor nerves when the skin is cooled down, might stimulate platelets to aggregation in skin vessels and to production and release of pruritogenic factors.
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PMID:Pruritus in polycythemia vera: treatment with aspirin and possibility of platelet involvement. 9 9

19 patients with cold urticaria, 5 with cold pruritus and 2 with cold rhinitis were successfully treated with peritol with the exception of one patient who suffered from a symptomatic pruritus due to polycythemia vera. Even in cases of recurrence the treatment was at once successful. Therefore peritol seems to be useful in the treatment of diseases due to cold.
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PMID:[Results of the treatment in cases of cold urticaria, cold pruritus and cold rhinitis with peritol (zyproheptadinhydrochlorid) (author's transl)]. 45 11

Polycythemia vera (PV) is one of the myeloproliferative diseases, and, as such, is an example of clonal hematopoiesis. The progeny of a single, abnormal, hematopoietic stem cell gain a growth advantage over their normal counterparts resulting in overproduction of red cells generally accompanied by overproduction of granulocytes and platelets as well. There are a variety of nonspecific symptoms at onset related to the increased red cell mass and hematocrit accompanied by the more specific manifestations of pruritus, erythromelalgia, and hepatic, portal, and mesenteric vein thrombosis. Splenomegaly and hypertension are common. The laboratory hallmark is an increased red cell mass. There is also often an increase in white cell count, platelet count, and leukocyte alkaline phosphatase along with other findings reflecting the increased rate of turnover of hematopoietic cells. The bone marrow biopsy generally displays hypercellularity involving all three cell lines and absent iron stores. The diagnosis of PV depends on excluding spurious polycythemia in which there is a high hematocrit but a normal red cell mass and secondary polycythemia in which there is an increased red cell mass in response to tissue hypoxia or the inappropriate production of erythropoietin, generally by a tumor. In addition, one should try to establish the diagnosis in a positive fashion by a combination of studies of the blood and bone marrow. Phlebotomy and occasionally plateletpheresis should be used as acute therapy. Chronic therapy is guided by the knowledge that patients treated with phlebotomy alone have an increased rate of thrombotic complications particularly in older patients and those with previous thrombotic disease. Myelosuppressive therapy can reduce the incidence of these complications, but is commonly associated with an increased incidence of second malignancies, particularly acute leukemia. At present, hydroxyurea is the myelosuppressive agent of choice. Antiplatelet agents have a limited role except in the palliation of the syndrome of erythromelalgia. Median survival is approximately 10 years. As implied above, the causes of morbidity and mortality vary with the mode of chronic therapy which has been employed, leukemia being more common after myelosuppressive therapy and thrombotic complications being more common after therapy with phlebotomy alone. Ten percent to 50% of patients move into a spent phase followed by postpolycythemic myeloid metaplasia, irrespective of previous therapy employed. Eventually, the major problems may be cytopenias and massive splenomegaly.
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PMID:Polycythemia vera. 158 7

In this paper the current knowledge on water-induced pruritus is reviewed. To the present, three forms, namely aquagenic pruritus (AP), aquagenic pruritus of the elderly (APE) and water-related itching in polycythemia rubra vera (PRV), have been recognized. Despite clinical similarities it appears that the pathophysiology is different in the three forms. The currently most effective treatment for AP is addition of sodium bicarbonate to the water, control of xerosis with emollients for APE and aspirin for water-induced itching in PRV.
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PMID:Water-induced itching. 224 90

The clinical characteristics of aquagenic pruritus (AP) based on a series of thirty-six patients are presented. AP is characterized by the development of severe, prickling-like skin discomfort that is without observable skin lesions and that is evoked by contact with water at any temperature. Other causes of pruritus associated with water contact must be excluded. In the thirty-six patients, skin discomfort developed within minutes of water contact in approximately half. In others, discomfort began 2 to 15 minutes after water exposure had ceased. The pruritus was usually generalized, lasting from 10 to 120 minutes (average, 40.6 minutes), and in 55% was associated with symptoms of acute emotional liability. There was no increased prevalence of atopy. Thirty-three percent reported a family history of water-related itching. Of fourteen patients treated with ultraviolet B phototherapy, eight (57%) noted significant relief. Of thirty-four patients, sixteen (47%) noted partial relief with oral antihistamine therapy. Patients with polycythemia rubra vera (PRV) may present with symptoms similar to those of AP, and all patients with symptoms consistent with AP should be investigated for the presence of PRV.
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PMID:Aquagenic pruritus. 241 68

Four patients with aquagenic pruritus (AP), one patient with polycythemia rubra vera, one patient with cold urticaria, and three normal control volunteers were studied to better understand the pathophysiology of water-induced itching. Punch biopsy specimens were taken before and after water contact; the specimens were immediately frozen, sectioned, and stained histochemically for acetylcholinesterase (AChE) activity. This was localized in the nerve fibers surrounding eccrine sweat glands and was quantified by microspectrophotometry. In AP and polycythemia rubra vera after water exposure a significantly increased AChE activity suggesting acetylcholine release was observed, whereas in the patient with cold urticaria and the controls, a significant decrease was noted. Two related patients with AP had an inherited abnormality of serum cholinesterase, which, however, had no obvious correlation with their particular disease. The proof of AChE activation might support the clinical diagnosis and indicate a hypothetical involvement of eccrine sweat glands in the pathogenesis of AP.
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PMID:Aquagenic pruritus. Water-induced activation of acetylcholinesterase. 333 47

This article reviews the neurophysiology of pruritus and presents evidence that itch is a separate modality from pain, rather than a submodality of pain. The numerous suggested pruritogens are reviewed, and evidence supporting each one is critically examined. The systemic causes of generalized pruritus are reviewed, with detailed review of the literature on uremic pruritus, cholestatic pruritus, and the pruritus associated with polycythemia vera. The specific treatments used for each of these conditions are reviewed, as well as the use of antihistamines in generalized pruritus. An approach to the workup of a patient with pruritus is suggested.
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PMID:A review of pruritus. 351 95

We studied blood histamine activity (HA) and cutaneous fibrinolytic activity (CFA) in a patient with polycythaemia rubra vera (PRV) and water-induced pruritus, before and after water exposure. The results suggest that the water-induced itching in PRV is associated with an increase in HA. In addition, markedly increased levels of CFA were found both before and after water exposure. These findings have been previously reported in patients with aquagenic pruritus (AP) but not in patients with PRV. As the water-induced itching in PRV and AP share many common features, these findings suggest that the pathophysiology of the water-induced pruritus in these two conditions may be similar.
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PMID:Polycythaemia rubra vera and water-induced pruritus: blood histamine levels and cutaneous fibrinolytic activity before and after water challenge. 356 71

Thirty-six patients with polycythemia vera were treated with hydroxyurea for 12 to 67 months. Nineteen patients were previously treated with other drugs. In the vast majority of patients, an average dose of 1 g/day was sufficient to control hematocrit value and platelet count. Half of the patients experienced relief of pruritus, and two thirds experienced regression of splenomegaly. None of the patients had either thrombotic complications or leukemia. Four patients suffered from mild side effects, which included fever, hyperbilirubinemia, and stomatitis, and were relieved of their symptoms when treatment was stopped. However, two patients experienced renal failure, a possible major complication not described previously.
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PMID:Treatment of polycythemia vera with hydroxyurea. 394 10

Aquagenic pruritus is now a well-recognized symptom complex, usually of unknown origin. A few prove to have polycythemia rubra vera. We describe an important and distinct subset, termed aquagenic pruritus of the elderly, in which old age, dry skin, and seasonal weather conditions are major factors. Unlike other varieties, aquagenic pruritus of the elderly responds to appropriate local measures.
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PMID:Water-induced itching without cutaneous signs. Aquagenic pruritus. 394 25


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