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Last reviewed: 20 Mar 2025
Last updated: 14 Mar 2025

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • calf swelling
  • pain or tenderness along deep venous system
  • chest pain
  • tachypnoea
  • breathlessness
  • hypotension
  • tachycardia

Other diagnostic factors

  • family history of venous thromboembolism (VTE)

Risk factors

  • history of unprovoked venous thromboembolism
  • increasing age
  • pregnancy/postpartum
  • obesity
  • smoking
  • malignancy
  • acute inflammatory state
  • antiphospholipid antibodies (aPLs)
  • myeloproliferative disorders
  • nephrotic syndrome
  • Behcet's disease
  • HIV infection
  • disseminated intravascular coagulation
  • paroxysmal nocturnal haemoglobinuria
  • heparin-induced thrombocytopenia
  • oestrogen-containing oral contraceptive pill/hormone replacement therapy/selective oestrogen receptor modulator therapy
  • chemotherapy
  • surgery
  • long-haul flight (>4 hours)
  • antithrombin deficiency
  • protein C deficiency
  • protein S deficiency
  • plasminogen deficiency
  • elevated fibrinogen
  • dysfibrinogenaemia
  • factor V Leiden
  • prothrombin gene mutation (G-20210-A; also referred to as F2 c.*97G>A variant)
  • elevated factor VIII levels (>150 U/L)
  • elevated levels of factor IX or XI
  • hyperhomocysteinaemia
  • sickle cell disease
  • elevated levels of thrombin-activatable fibrinolysis inhibitor (TAFI)

Diagnostic investigations

1st investigations to order

  • FBC
  • peripheral blood smear
  • activated partial thromboplastin time (aPTT)
  • fibrinogen
  • prothrombin time (PT)
  • D-dimer
  • serum albumin
  • serum creatinine
  • serum cholesterol
  • serum triglycerides

Investigations to consider

  • heritable thrombophilia test
  • polymerase chain reaction (PCR) for factor V Leiden
  • antiphospholipid antibodies (lupus anticoagulant, anticardiolipin antibodies, anti-beta-2 glycoprotein 1 antibodies)
  • homocysteine level
  • factor VIII level
  • myeloproliferative neoplasm panel
  • flow cytometry for paroxysmal nocturnal haemoglobinuria
  • heparin-induced thrombocytopenia (HIT) test
  • chest x-ray
  • abdominal CT
  • abdominal ultrasound
  • tumour markers
  • 24-hour urine collection for protein, or spot urine for protein/creatinine ratio

Treatment algorithm

Contributors

Authors

Lara N. Roberts, MBBS, MD (Res), FRCP, FRCPath
Lara N. Roberts

Consultant Haematologist

King's Thrombosis Centre

King's College Hospital

London

UK

Disclosures

LNR has received speaker fees from Bayer and Viatris.

Roopen Arya, BMBCh (Oxon), MA, PhD, FRCP, FRCPath
Roopen Arya

Professor of Thrombosis and Haemostasis

King's Thrombosis Centre

King's College NHS Foundation Trust

London

UK

Disclosures

RA declares that he has no competing interests.

Peer reviewers

Beverly Hunt, FRCP, FRCPath, MD

Professor of Thrombosis & Haemostasis

King's College

Consultant

Departments of Haematology, Pathology & Rheumatology

Lead in Blood Sciences

Guy's & St Thomas' NHS Foundation Trust

London

UK

Disclosures

BH declares that she has no competing interests.

Per Morten Sandset, MD, PhD

Senior Consultant and Head of Department

Oslo University Hospital Ullevål

Department of Hematology

Professor in Hematology

University of Oslo

Oslo

Norway

Disclosures

PMS declares that he has no competing interests.

Michael Bromberg, MD, PhD

Associate Professor

Director of Hematologic Malignancies

Medicine and Pharmacology

Temple University School of Medicine

Philadelphia

PA

Disclosures

MB declares that he has no competing interests.

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