Antithrombin III deficiency in a patient with recurrent venous thromboembolism: A case report.

BACKGROUND: Antithrombin III (AT3) deficiency, an autosomal dominant disease, increases the likelihood of an individual developing venous thromboembolism (VTE). Long-term anticoagulation treatment is required for those suffering from AT3 deficiency. CASE SUMMARY: A man aged 23, who had a history of deep venous thrombosis (DVT), experienced recurrent pain and swelling in his right lower extremity for three days following withdrawal of Rivaroxaban. He was diagnosed with DVT and antithrombin III deficiency as genetic testing revealed a single nucleotide variant in SERPINC1 (c.667T>C, p.S223P). The patient was advised to accept long-term anticoagulant therapy. CONCLUSION: Inherited AT3 deficiency due to SERPINC1 mutations results in recurrent VTE. Patients may benefit from long-term anticoagulant therapy.