[Acute venous disorders: deep vein thrombosis and superficial vein thrombosis of the lower extremity : Diagnosis and treatment in dermatology practice].

BACKGROUND: Deep vein thrombosis (DVT) is associated with potentially serious complications such as pulmonary embolism (PE) and postthrombotic syndrome. Superficial vein thrombosis (SVT) is also clinically relevant, as concomitant DVT and/or PE may already be present at initial diagnosis or may develop during follow-up.

OBJECTIVE: Which diagnostic and therapeutic steps are most relevant for dermatologists in clinical practice?

METHODS: Overview of the German S2k guideline and selected literature, supplemented by two case vignettes.

RESULTS: DVT diagnostics are guided by clinical pretest probability (Wells score). In patients with low probability, a negative D‑dimer test can rule out DVT. In patients with high probability or a positive D‑dimer test, duplex compression ultrasonography is indicated. In confirmed DVT, prompt therapeutic anticoagulation is required, preferably with direct oral anticoagulants, usually for ≥ 3 months depending on provocation status and risk of recurrence. In SVT, thrombus length and proximity to the deep venous junction determine management. SVT ≥ 5 cm, marked symptoms, or relevant risk factors warrant 45 days of anticoagulation (e.g., fondaparinux 2.5 mg s.c. once daily). SVT < 3 cm from the junction or with progression into the deep venous system requires therapeutic-dose anticoagulation analogous to DVT. Short-segment distal SVT can often be managed symptomatically.

CONCLUSION: Structured risk stratification, focused diagnostic work-up, and guideline-concordant therapy are essential to prevent thromboembolic complications.