Diagnosis and Treatment of Primary Polycythæmia

Clinical Problems: Progressive Neurological Deficits in Primary Polycythaemia

“…3 Although not performed in Case 1, the level of the haemoglobin and the presence of splenomegaly make a "pseudopolycythaemia" unlikely.…”

Polycythemia vera: myths, mechanisms, and management

“…76,120 By contrast, in polycythemia vera where erythropoiesis is autonomous and erythropoietin production is suppressed, as the red cell mass increases the plasma volume may be unchanged or increase 121 until the hematocrit level is more than 60%. 122 Unfortunately, the hematocrit level, whether directly determined by centrifugation or calculated from the mean corpuscular volume (MCV) and the red cell count, will not reflect these changes because even under normal circumstances, the distribution of red cells and plasma is not uniform throughout the circulatory system. [123][124][125] Rather, as demonstrated by independent determinations of the red cell mass and plasma volume, the ratio of red cells to plasma is higher in the peripheral vessels, venous or arterial, than it is in the body as a whole (ie, whole body hematocrit derived from independent measurements of red cell mass and plasma volume/peripheral venous hematocrit ϭ 0.92).…”

“…Indeed, even today, there are advocates of 32 P therapy, 201,245 although it has been widely appreciated for 50 years that this agent was least effective against the most troublesome feature of polycythemia vera, extramedullary hematopoiesis. 167,189,246 Central to the myth of survival is the assumption that polycythemia vera is a monolithic disease when in fact it is not 122,146,246,247 and while no one would advocate withholding treatment once the diagnosis was established, it is important to emphasize that the disease can develop gradually and be substantially advanced before it becomes clinically problematic ( Figure 2). Presumably, this is a consequence not only of the slow rate of hematopoietic cell accumulation but also the concomitant compensatory expansion of the plasma volume.…”

Chorea, polycythaemis, and cyanotic heart disease.

“…Several of the early accounts, beginning with Vaquez's classic case of vertigo (Vaquez, 1892), mentioned the nervous system (Cabot, 1899;Osler, 1903;Hutchison and Miller, 1906) and a neurological syndrome soon became commonplace in the natural history of the disorder (Jacobs, 1912;Lucas, 1912;Christian, 1917;Weber, 1921;Brockbank, 1929;Sloan, 1933;de Secondi, 1940). In recent years, the predominance of cerebral symptoms has emerged from many reviews and the neurological complications of polycythaemia, both central and peripheral, are now regarded as a major source of morbidity and mortality (Tinney et al, 1943;Videbaek, 1950;Johnson and Chalgren, 1951;Lawrence et al, 1953;Calabresi and Meyer, 1959;Croizat et al, 1960;Silverstein et al, 1962;Campbell et al, 1970).…”