Secondary erythrocytosis

ABSTRACT

Introduction

Erythrocytosis is associated with an elevation of the hemoglobin level above 16.5 g/dL in men and above 16 g/dL in women and an elevation of the hematocrit level above 49% in men and > 48% in women. In primary erythrocytosis, the defect is a clonal disorder in the myeloid compartment of the bone marrow, leading to an increased red cell production. Secondary erythrocytosis is the result of external stimuli to the bone marrow, leading to the production of red cells in excess. Secondary erythrocytosis is more common than primary erythrocytosis and has a broad differential diagnosis.

Areas covered

This review will discuss secondary erythrocytosis, its causes, clinical presentation, and both diagnostic and therapeutic approaches.

Expert opinion

Although secondary erythrocytosis is more common than PV, there are still challenges and difficulties associated with the distinction between these two conditions. Moreover, there is a paucity of data and guidance when it comes to the management of certain congenital and acquired conditions. A pragmatic approach is recommended in order to identify the cause for this condition. Treatment should be directed at the management of the underlying cause.

KEYWORDS:

• Secondary erythrocytosis
• secondary polycythemia
• erythropoietin
• congenital erythrocytosis
• acquired erythrocytosis

Article highlights

• Erythrocytosis is associated with an elevation of the hemoglobin level above 16.5 g/dL in men and above 16 g/dL in women and an elevation of the hematocrit level above 49% in men and >48% in women

• Secondary erythrocytosis occurs when external stimuli promote an excess production of erythropoietin resulting in an increased erythropoiesis

• Secondary erythrocytosis can be divided into rare congenital and more common acquired forms

• The clinical picture in secondary erythrocytosis varies and may be determined by the underlying disease as well as the severity of erythrocytosis, and thus, the level of blood viscosity

• There is no generalized treatment approach to secondary erythrocytosis.

• Treatment depends on the underlying etiology and in some cases should incorporate interdisciplinary management

Declaration of interest

CM Rojas-Hernandez has received research funding support from Daiichi Sankyo and ANTHOS Pharmaceuticals. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers of this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.