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Essential Thrombocytosis Clinical Presentation

  • Author: Asheesh Lal, MBBS, MD; Chief Editor: Emmanuel C Besa, MD  more...
Updated: Nov 06, 2015


Approximately 25-33% of patients with essential thrombocytosis (primary thrombocythemia) are asymptomatic at diagnosis. The remainder report vasomotor symptoms or complications from thrombosis or bleeding. Most symptomatic patients present with symptoms that relate to small- or large-vessel thrombosis.

Neurologic symptoms are as follows:

  • Headache is the most common neurologic symptom
  • Microvascular occlusion of the toes and fingers causes digital pain; gangrene; or erythromelalgia, which is is characterized by burning pain and dusky extremity congestion
  • The pain increases with exposure to heat and improves with cold; a single dose of aspirin may provide relief for several days
  • Patients also report paresthesias and episodic transient ischemic attacks; transient neurologic symptoms include the following:
    • Unsteadiness
    • Dysarthria
    • Dysphoria
    • Vertigo
    • Dizziness
    • Migraine
    • Syncope
    • Scotoma
    • Seizures

Thrombosis of large veins and arteries is common and may result in occlusion of the leg, coronary, and renal arteries. Other arteries may be involved. Venous thrombosis of the splenic, hepatic, or leg and pelvic veins may develop. Priapism is a rare complication. Pulmonary hypertension may result from pulmonary vasculature occlusion.

Bleeding complications are as follows:

  • The gastrointestinal tract is the primary site of bleeding complications; approximately 40% of these patients have duodenal arcade thrombosis, resulting in sloughing of the duodenal mucosa, simulating a duodenal ulcer
  • Other sites of bleeding include the skin, eyes, gums, urinary tract, joints, and brain
  • Bleeding is usually not severe and only rarely requires transfusion
  • The bleeding is generally associated with a platelet count greater than 1 million/µL

Constitutional symptoms (occur in 20-30% of patients). Weight loss is unusual. Other symptoms include sweating, low-grade fever, and pruritus.

Pregnancy complications are as follows[19] :

  • Spontaneous abortions increase
  • Placental infarctions may occur, resulting in intrauterine growth retardation and fetal death.
  • In most cases, fetal loss occurs during the first trimester
  • A patient history of spontaneous abortion is the greatest risk factor for subsequent spontaneous abortions
  • Excessive bleeding during delivery is rare
  • Patients with successful pregnancies show a decrease in platelet count


In most patients with essential thrombocytosis, physical examination findings are unremarkable. Approximately 40-50% of patients present with splenomegaly; 20% present with hepatomegaly.



The etiology and predisposing factors for the development of essential thrombocytosis (primary thrombocythemia) remain unclear. Genetic transmission of this disorder is rare, although reports show several families with multiple members affected by essential thrombocytosis (primary thrombocythemia). Research suggests that a thrombopoietin production or receptor abnormality can cause familial essential thrombocytosis (primary thrombocythemia).[20]

Contributor Information and Disclosures

Asheesh Lal, MBBS, MD Physician, Department of Internal Medicine, Lexington Medical Center

Asheesh Lal, MBBS, MD is a member of the following medical societies: American Society of Clinical Oncology, American Society of Hematology

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Marcel E Conrad, MD Distinguished Professor of Medicine (Retired), University of South Alabama College of Medicine

Marcel E Conrad, MD is a member of the following medical societies: Alpha Omega Alpha, American Association for the Advancement of Science, American Association of Blood Banks, American Chemical Society, American College of Physicians, American Physiological Society, American Society for Clinical Investigation, American Society of Hematology, Association of American Physicians, Association of Military Surgeons of the US, International Society of Hematology, Society for Experimental Biology and Medicine, SWOG

Disclosure: Partner received none from No financial interests for none.

Chief Editor

Emmanuel C Besa, MD Professor Emeritus, Department of Medicine, Division of Hematologic Malignancies and Hematopoietic Stem Cell Transplantation, Kimmel Cancer Center, Jefferson Medical College of Thomas Jefferson University

Emmanuel C Besa, MD is a member of the following medical societies: American Association for Cancer Education, American Society of Clinical Oncology, American College of Clinical Pharmacology, American Federation for Medical Research, American Society of Hematology, New York Academy of Sciences

Disclosure: Nothing to disclose.


Wadie F Bahou, MD Chief, Division of Hematology, Hematology/Oncology Fellowship Director, Professor, Department of Internal Medicine, State University of New York at Stony Brook

Wadie F Bahou, MD is a member of the following medical societies: American Society of Hematology

Disclosure: Nothing to disclose.

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Peripheral blood smear in essential thrombocytosis showing increased platelet numbers. Courtesy Wei Wang, MD, and John Lazarchick, MD; Department of Pathology, Medical University of South Carolina.
Bone marrow biopsy in essential thrombocytosis showing increased megakaryocytes. Courtesy Wei Wang, MD, and John Lazarchick, MD; Department of Pathology, Medical University of South Carolina.
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