The most common cause of an increase of the hematocrit is secondary to elevated erythropoietin levels. Erythrocytosis is assumed to cause higher blood viscosity that could put the cardiovascular system at hemodynamic and rheological risks. Secondary erythrocytosis results from tissue hypoxia, and one can hardly define what cardiovascular consequences are caused by chronic erythrocytosis or hypo...

Polycythemia vera (PV) is characterized by low serum total cholesterol despite its association with vascular events such as myocardial and cerebral infarction. Serum cholesterol level has not been used as a diagnostic criterion for PV since the 2008 revision of the WHO classification. Therefore, we revisited the relationship between serum lipid profile, including total cholesterol level, and er...

Sir, European guidelines for long-term management of the transplant patients were published in your journal in 2002. Section IV.9.3 of these guidelines discusses post-transplant erythrocytosis [1]. It refers to the paper of Wickre et al. [2] and claims that: ‘One study in 53 polycythaemic transplant patients failed to find any increased incidence of thromboembolic events’. In fact, upon reviewi...

While secondary erythrocytosis is often associated with tumors arising from the kidney, other tumors have been described to originate in the liver, uterus, ovary, adrenal gland, and central nervous system, among which cerebellar hemangioblastomas are involved in most instances. Two cases of meningioma associated with erythrocytosis have already been reported. We observed a 59-year-old female pa...

We investigated the pathogenesis of isolated erythrocytosis of 14 yr duration in a 28-yr-old man. The increase in red cell mass was attributed to increased erythropoietin production. An extensive search for recognized causes of secondary erythrocytosis was unrevealing. Family members were found to be hematologically normal. After reduction of the circulating red cell mass by 20%, erythropoietin...

Erythroid colony growth in the presence and absence of erythropoietin was compared in 23 patients with primary proliferative polycythaemia (PPP), nine with idiopathic erythrocytosis, 10 with secondary polycythaemia, 15 with pseudopolycythaemia and in 76 normal subjects. Erythroid colonies growing without erythropoietin stimulation (endogenous erythroid colonies) from peripheral blood (BFU-E) we...

The oxygen sensing pathway modulates erythropoietin expression. In normal cells, intracellular oxygen tensions are directly sensed by prolyl hydroxylase domain (PHD)-containing proteins. PHD2 isozyme has a key role in tagging hypoxia-inducible factor (HIF)-α subunits for polyubiquitination and proteasomal degradation. Erythrocytosis-associated PHD2 mutations reduce hydroxylation of HIF-α. The i...

Populations living at high altitudes (HAs), particularly in the Peruvian Andes, are characterized by a mixture of subjects with erythrocytosis (16 g dl(-1)21 g dl(-1)). Elevated haemoglobin values (EE) are associated with chronic mountain sickness, a condition reflecting the lack of adaptation to HA. According to c...

Nephrocalcinosis: another cause of renal erythrocytosis Although erythrocytosis is not a recognised complication of nephro-calcinosis, in the course of a study of 250 patients with nephro-calcinosis we found nine patients with raised blood haemoglobin concentration and haematocrit value. All patients had radiological medullary nephrocalcinosis, of varying underlying cause (two primary hyperpara...

Secondary erythrocytosis in cyanotic congenital heart disease (CCHD) is a compensatory response to chronic hypoxia which should be managed with caution. CCHD patients, who have compensated erythrocytosis but do not manifest significant neurologic symptoms, may experience secondary life-threatening complications such as stroke in case of inappropriate phlebotomy. This study reports a young man w...