Management of Superficial Thrombophlebitis (STP) in Secondary Care

N.B. This guideline relates to non-pregnant adults.

Introduction

Superficial vein thrombosis, also known as superficial thrombophlebitis (STP), is a common condition, likely more common than deep vein thrombosis. It is a painful condition affecting the superficial veins, usually of the lower limbs. It should not be confused with superficial femoral vein thrombosis, as this is thrombosis in a deep vein and requires full anticoagulation therapy.

STP can occur alone or in association with deep vein thrombosis (DVT). In people with STP 6-44% are associated with or develop DVT, 20-33% with asymptomatic pulmonary embolism (PE) and 2-13% with symptomatic PE. Those associated with the great saphenous vein appear to have the strongest association with venous thromboembolism.

The aims of management include:

  • Detection and treatment of DVT
  • Symptomatic relief of STP
  • Prevention of both extension of STP and development of DVT

Diagnosis

STP is usually a clinical diagnosis based on symptoms of localised swelling, erythema and pain with tenderness over the affected vein. Patients should be assessed for risk factors for DVT and an assessment using the Wells score should be carried out to encourage consideration of this complication. Any chest symptoms should also be taken seriously and PE considered in the differential.

Most patients presenting to hospital with symptoms suggestive of STP should have a compression Doppler USS to assess the length and position of the superficial thrombus and exclude a concurrent DVT.

Note:
Those presenting with STP in the community should be referred to their local DVT service for a Doppler USS if there is either clinical evidence of concurrent DVT or the STP has features indicative of a high risk of STP extension, recurrence or progression to DVT. The DVT pageholder can be contacted via switchboard.

These include the following:

  • STP involves the main trunk of the great saphenous vein (rather than its branches)
  • history of VTE
  • cancer
  • absence of varicose veins
  • severe chronic venous insufficiency

These recommendations are based on the fact that studies of the epidemiology and natural history of STP have focused on cases referred to hospital or vascular laboratories for assessment and therefore are likely biased towards the more clinically severe forms of the condition. Furthermore, the evidence for aggressive treatment of STP, as outlined below, is limited to those presenting to secondary care.

Drug therapy / treatment options

Any STP <3cm from the saphenofemoral junction (SFJ) should be treated as a DVT as the rate of extension to DVT in these patients is very high.

Various treatments have been used for STP, including compression stockings, NSAIDs, LMWH, rivaroxaban, surgical intervention and topical agents.

Two recent studies have demonstrated both fondaparinux and rivaroxaban to be effective in the management of STP, resulting in a reduction in the incidence of DVT and PE. In one study, fondaparinux was demonstrated to be superior to placebo. Due to non-submission, fondaparinux is not recommended by SMC. A more recent study has demonstrated that rivaroxaban is non-inferior to fondaparinux with no increased risk of bleeding.

Based on the above data, it is recommended that patients with a STP of >5cm in length, who do not meet the criteria for therapeutic anticoagulation, receive rivaroxaban 10mg once daily for 6 weeks, as long as there are no contraindications to its use.

Rivaroxaban should be used in preference to fondaparinux for the following reasons:

  • Oral medication is likely to be more acceptable to patients than parenteral treatment
  • Rivaroxaban has a lower acquisition cost than fondaparinux.

If rivaroxaban is not suitable or contraindicated, dalteparin should be used as this is the prophylactic LMWH used in NHS Ayrshire & Arran. The use of dalteparin or rivaroxaban for this indication is off-label.

Table 1 – Treatment recommendations

Example Details of Doppler USS request:

'Suspect STP in greater saphenous vein proximal to the knee. Please assess length and site of STP (in relation to the SFJ) and exclude DVT'

No STP or DVT identified STP ≤3cm from SFJ STP >3cm from SFJ; STP ≥5cm in length STP >3cm from SFJ; STP <5cm in length

Alternative diagnosis for symptoms should be sought

Therapeutic anticoagulation for 3 months (as per DVT guideline ADTC302 on AthenA - link only active if accessing via NHS network)

Rivaroxaban oral 10mg once daily for 6 weeks (42 days) - off-label

NSAIDs for 8-12 days for symptomatic relief only

Notes

  • Patients unsuitable for prophylactic rivaroxaban (see below) should receive dalteparin SC 5000 units once daily.
  • For patients unsuitable for LMWH, consider the use of NSAIDs e.g. ibuprofen oral 400mg 8hourly (for symptomatic relief only) or consider discussion with the vascular team to explore surgical options. Avoid NSAIDs in patients prescribed an anticoagulant. 
  • Grade 1 below the knee compression stocking is recommended for all patients. ABPIs should be considered in patients in whom PVD in their legs is possible.
    • Contraindications to stockings include neuropathy and inability to remove the stockings should they be too tight.
    • ABPIs can also be considered if wishing to increase compression.
    • Information and stocking care should be provided to the patient.
    • Clinical information on when a patient requires to start wearing stockings, sizings, quantities and duration will be supplied by clinician on the patient’s Immediate Discharge Letter.
  • All patients receiving LMWH or rivaroxaban should have a baseline FBC and coagulation screen.
  • Anticoagulation for patients at under 50kg or over 150kg, or with significant CKD, should be discussed with a pharmacist and/or haematologist/renal physician.
  • If a scan reports on a STP distal to the knee >5cm in length, prophylactic dose rivaroxaban or LMWH can also be considered. There is no evidence on the use of therapeutic anticoagulation if the STP is <3cm from the SPJ. Therapeutic anticoagulation (treating as a DVT) for 3 months can be given based on clinical judgement.
  • Patients requiring therapeutic anticoagulation should be treated as those with deep vein thrombosis - please see ADTC 302 for prescribing guidance (link only active if accessing via NHS network).

Unsuitability for rivaroxaban would include (refer to BNF for interactions and contraindications):

  • Pregnancy, breast feeding
  • eGFR <15ml/min/1.73m2
  • Liver disease with cirrhosis and/or coagulopathy
  • Concurrent use of triazoles and imidazole antifungals (except fluconazole), protease inhibitors, strong CYP3A4 inducers, e.g. rifampicin.

 

Guideline reviewed December 2022
Page updated January 2025



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