Nickan Research Institute Journal of Parathyroid Disease 2345-6558 10 1 2022 01 01 Bilateral upper extremity thrombosis associated with protein C deficiency in a COVID-19 patient; a case report e10149 e10149 10.34172/jpd.2022.10149 EN Zahra Ansari Aval https://orcid.org/0000-0002-6044-8259 Seyed Mohsen Mirhosseini https://orcid.org/0000-0002-2903-682X Sepideh JafariNaeini https://orcid.org/0000-0002-3173-1717 Hamid Ghaderi https://orcid.org/0000-0003-0905-2440 Seyedeh Adeleh Mirjafari https://orcid.org/0000-0003-2780-6736 Journal Article 10.34172/jpd.2022.10149 2022 09 03 2022 10 15 The coronavirus disease 2019 (COVID-19) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has affected different communities all over the world. A wide spectrum of complications has been reported due to COVID-19 infection, among which a hypercoagulability state is one of the most significant. The patient was a 44-year-old obese woman with a history of diabetes, hypothyroidism, cigarette smoking and opium addiction, who had recently been diagnosed with COVID -19 and had undergone cardiac surgery due to right atrial thrombosis. The patient was also affected by bilateral upper extremity thrombosis 20 days after surgery. Protein C deficiency was diagnosed by measuring serum levels and she was discharged from the hospital with apixaban instead of warfarin due to protein c deficiency.