Thrombus may form in superficial veins, impeding drainage to the deep veins and eventually disrupting venous return. (1)
Thrombophlebitis migrans may herald the presence of visceral carcinoma - Trousseau's sign.
Virchow's triad provides a framework for thinking about thrombosis. Pathophysiologic risk factors for the development of superficial vein thrombosis (SuVT) include (2):
- endothelial injury (caused by infection or intravenous devices),
- venous stasis (such as from chronic venous insufficiency or prolonged immobility),
- hypercoagulability (due to cancer or pregnancy)
The incidence of SuVT is greater in females than males.
Varicose veins are considered the most important clinically identifiable predisposing factor (3).
Other stated risk factors of SuVT are (3):
- advanced age,
- exogenous estrogens,
- autoimmune or infectious diseases,
- obesity,
- recent trauma or surgery,
- active malignancy,
- history of venous thromboembolic disease,
- and respiratory or cardiac failure
Lower extremity SuVT versus upper extremity SuVT
- clinical risk factors for lower extremity SuVT are similar to those of deep vein thrombosis (DVT) and pulmonary embolism (PE) and include pregnancy, varicose veins, and active cancer
- upper extremity SuVT is primarily caused by indwelling intravenous catheters
- SuVT generally affects lower limbs, especially the great saphenous vein (60% to 80%) or the small/short saphenous vein (10% to 20%) (3)
- can occur at other sites (10% to 20%) and may occur bilaterally (5% to 10%)
Clinical features:
- typically present with a tender, red, palpable cord under the skin in the upper or lower extremity
- some surrounding edema or associated pruritis may occur (3)
- significant swelling of the limb is more commonly associated with DVT and should only be attributed to SuVT after DVT has been excluded (3)
Approximately 10% of patients with superficial vein thrombosis (SuVT) progress to deep vein thrombosis (DVT) or pulmonary embolism (PE) (2)
- about 25% of patients with lower extremity SuVT present with concomitant DVT
- this is probably because risk factors for SuVT and DVT are similar
- also SuVT can extend into deep veins
D-dimer in diagnosis of SuVT
- has a sensitivity of approximately 48% to 74.3% and, therefore, is not reliable for excluding SuVT (2)
Ultrasound in SuVT
- can identify concomitant DVT, evaluate the extent of the thrombus, and confirm the diagnosis (3)
SuVTs within 3 cm of a deep vein should be treated with therapeutic dose anticoagulation (2).
Reference:
- Thrombosis Canada. Superficial thrombophlebitis, superficial vein thrombosis. Aug 2023 [internet publication].
- Piazza G, Krishnathasan D, Hamade N, et al. Superficial Vein Thrombosis: A Review. JAMA. 2025;334(22):2020–2030.
- Czysz A, Higbee SL. Superficial Thrombophlebitis. [Updated 2023 Jan 2]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-.