Clinical Characteristics of Plethora in Polycythemia Vera

Clinical Manifestation

• The American Society of Hematology notes that plethora represents one of the classic clinical phenotypes of Polycythemia Vera, characterized by a ruddy or reddish-purple discoloration of the face and skin, particularly noticeable in sun-exposed areas, due to increased red blood cell mass and engorged superficial blood vessels 1, 2
• Patients with Polycythemia Vera often exhibit engorged superficial veins that are visibly distended due to increased blood volume, as well as conjunctival injection with redness of the eyes 1, 2

Pathophysiologic Basis

• Vascular engorgement from the expanded blood volume filling superficial vessels contributes to the plethoric appearance in patients with Polycythemia Vera 1

Clinical Significance

• The presence of plethora serves as an important diagnostic clue when evaluating patients for Polycythemia Vera, and its improvement can be expected with therapeutic phlebotomy, which reduces hematocrit to target levels below 45% 1, 2