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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Spurious polycythemia is not a primary disease process. It sometimes may be nothing more than an unusual, but normal, physiologic state. In other instances, however, it is associated with a true abnormality of plasma volume. Although there is probably overlap between these extremes, differentiation of these subclasses may be of prognostic significance. The elevation in hematocrit bears no relation to morbidity, and, because there is no evidence of abnormal erythroid proliferation, reduction of red cell volume via phlebotomy or myelosuppression is inappropriate. Nonhematologic parameters, particularly hypertension, are the major factors of significance in the substantial cardiovascular morbidity in spurious polycythemia, and they demand attentive and aggressive management.
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PMID:Spurious polycythemia. 119 27

The investigation of elderly patients presenting with raised PCV values has been described. Suitable clinical and laboratory investigation enables the separation of those with a raised red cell mass (RCM) into three groups: primary proliferative polycythaemia (PPP), secondary polycythaemia and idiopathic erythrocytosis. Those patients with a raised PCV but normal RCM either have apparent polycythaemia (normal plasma volume) or relative polycythaemia (low plasma volume). PPP is a clonal disorder with a peak incidence in the elderly. It commonly presents with vascular occlusive symptoms/signs involving larger vessels, both arterial and venous. The microvasculature may also be involved, particularly when there is associated thrombocythaemia. Effective treatment is required to minimize the future vascular occlusive incidence and diminish the complication rate of surgery if it is ever required. Both the PCV and the platelet count, if elevated, should be adequately controlled. 32P is probably the simplest treatment and is very effective, but venesection and intermittent low-dose busulphan is equally satisfactory in the co-operative patient with good peripheral veins. Secondary polycythaemia may arise from a variety of causes, particularly from arterial hypoxaemia and renal lesions. Occasionally, more than one pathology is identified in the elderly patient. Lung disease is the most common cause of hypoxaemia. Venesection may be indicated in those patients with excessively raised PCV values. The term idiopathic erythrocytosis should only be used for patients who have been adequately investigated. These patients most commonly present with ischaemic or vascular occlusive symptoms/signs. Relative polycythaemia may be caused by fluid loss, but generally the origin of the low plasma volume is not established. Apparent polycythaemia may represent a physiological variant or a stage before the development of a definitely raised RCM. The management of idiopathic erythrocytosis, and relative and apparent polycythaemia, should initially involved removal of known risk factors if present (e.g. hypertension) with the addition of venesection in selected patients. Reactive thrombocytosis in the elderly is most commonly due to malignant disease of chronic infection. The high platelet count is usually asymptomatic, and antiplatelet therapy is rarely required. Primary thrombocythaemia (PT) is a clonal myeloproliferative disorder similar to PPP. The finding of splenomegaly, abnormal platelet morphology or function helps to separate PT from reactive thrombosis. PT most commonly presents with digital or transient cerebral ischaemia or haemorrhage.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Polycythaemia and thrombocythaemia in the elderly. 332 42

Relative polycythaemia is a general term which includes patients with a normal red cell mass but a contraction of the plasma volume as the cause for the polycythaemia. The relative polycythaemias can broadly be divided into two groups. Firstly, relative polycythaemia may be due to a primary loss of plasma volume due to dehydration, capillary leak or hypo-oncotic pressure. Secondly, relative polycythaemia may be due to a primary contraction of the vascular compartment (i.e. reduced venous compliance). It is this second group which is the least understood and is analysed in detail in this review. In general, this group of polycythaemias is secondary to exogenous or endogenous stress and is mediated via the sympathetic nervous system. Hypoxia, smoking, neurological disorders, myocardial infarction and acute psychological stress have all been demonstrated as possible factors. In many cases of chronic stress polycythaemias aetiological factors may be identified, whereas in others the term idiopathic is probably appropriate. There appears to be a relationship between the idiopathic stress polycythaemias, hypertension and psychological stress. Other patients may have primarily a disorder of blood volume control involving the autonomic nervous system and its receptors. The haemorheological significance of relative polycythaemia and its management are discussed. Treatment is generally dictated by the underlying cause. In stress polycythaemias the stimulus should be removed as far as possible. However, in some patients with chronic idiopathic stress polycythaemia, regular venesection may be required to maintain the venous haematocrit at an appropriate level.
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PMID:The contracted plasma volume syndromes (relative polycythaemias) and their haemorheological significance. 332 61

Erythrocytosis is a relatively common phenomenon following renal transplantation. It is not only associated with some special clinical conditions, but also increases the risk of thromboembolism. We therefore studied the clinical manifestations and possible risk factors of erythrocytosis in our renal-transplant patients. Study of 175 patients showed that erythrocytosis, defined as Hct > or = 50%, was found in 17 patients (9.7%), 14 males and 3 females. Among these 17 patients, 13 received cadaveric grafts and the other 4 living-related grafts. True erythrocytosis, defined as erythrocytosis with elevated red blood cell (RBC) mass, was found in 7 patients. Relative erythrocytosis, defined as erythrocytosis with normal RBC mass, was found in the other 10 patients. Six patients developed acquired renal cysts of the native or graft kidneys during the post transplant period. The incidence of acquired renal cysts in the erythrocytosis group was significantly higher than that in the non-erythrocytosis group. The clinical and demographic characteristics were similar in terms of age, gender, serum albumin, and serum creatinine in the erythrocytosis and non-erythrocytosis groups. The incidences of abnormal liver function, and hypertension were similar between the 2 groups. Seventeen of the 161 patients (10.6%) receiving cyclosporine regimen developed erythrocytosis, but none of the 14 patients receiving non-cyclosporine regimen developed erythrocytosis (p > 0.05). Only one patient with true erythrocytosis had an elevated serum erythropoietin (EPO) level and no thromboembolic complications occurred in the erythrocytosis group. We conclude that: (1) the incidence of erythrocytosis in our transplant patients was 9.7%; (2) a higher incidence of acquired renal cysts was found in the erythrocytosis group; (3) most of the patients with erythrocytosis had a normal serum EPO level; (4) no thromboembolic complications occurred in our patients.
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PMID:Post-renal transplant erythrocytosis. 892 41

A 46-year-old man suspected of spurious polycythemia received nephrectomy. Spurious polycythemia patients with high blood pressure as a complication have a high possibility of developing cerebral vascular disease. For its prevention, it is important to decrease blood viscosity by phlebotomy and to perform anticoagulation therapy. It is also necessary to deal with these patients as a high-risk group of cerebral vascular disease even if there is no symptoms. We were able to manage this case safely without any complication by aggressive perioperative phlebotomy and anticoagulation therapy.
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PMID:[Anesthesia for nephrectomy in a patient suspected of spurious polycythemia]. 1802 10