History
Patients with a high red blood cell mass usually have plethora or a ruddy complexion. However, if the polycythemia is secondary to hypoxia, as in venous-to-arterial shunts or compromised lung and oxygenation, patients can also appear cyanotic.
Increased red blood cell mass increases blood viscosity and decreases tissue perfusion. With impaired circulation to the central nervous system, patients may present with headaches, lethargy, and confusion or more serious presentations, such as stroke and obtundation. In addition, polycythemia potentially predisposes patients to thrombosis. [3]
Congenital heart diseases manifest at birth or in early childhood. In some cases, a family history of congenital heart disease may be present.
Patients with familial hemoglobinopathies that result in increased oxygen affinity usually have a family history of similar problems in several family members, although significant numbers of patients with congenital polycythemia have no family history of similar disorders. [19]
Chronic pruritus in the absence of a rash is more indicative of a primary myeloproliferative disorder than of secondary polycythemia.
Physical Examination
Plethora manifests as increased redness of the skin and mucosal membranes. This finding is easier to detect on the palms or soles, where the skin is light in dark-skinned individuals. Some patients may have acrocyanosis caused by sluggish blood flow through small blood vessels.
The presence of splenomegaly supports a diagnosis of polycythemia vera rather than secondary polycythemia. Cardiac murmurs and clubbing of the fingers may suggest a congenital heart disease.
