SUN-249 Testosterone-induced Polycythemia Leading To Life-threatening Venous Thromboembolism: A Case Report

Abstract Disclosure: A. Al-Thunaibat: None. L.L. Ponce Rosas: None. K. Sanu: None. A. Abualnil: None. J.S. Martins Torrontegui: None. C. Penaherrera: None. Introduction: The use of testosterone has become increasingly prevalent in recent years, both through medical prescriptions and non-medical, unauthorized channels. While testosterone is primarily prescribed for the management of hypogonadism, it is also widely misused by athletes and bodybuilders to enhance muscle mass and physical performance due to its anabolic effects. Herein, we presented a case of PE and DVT secondary to testosterone use in a patient with no other risk factors for venous thromboembolism (VTE). Case Presentation: A 45-year-old male with a medical history of HTN, primary hypogonadism, polycythemia secondary to testosterone supplement, asthma, and OSA on CPAP presented to the ED with progressive shortness of breath. He had been on testosterone replacement therapy (TRT) for over seven years. Due to polycythemia, he was advised to undergo therapeutic phlebotomy twice monthly but had been non-compliant for the past month. On presentation, laboratory results showed Hgb 17.8 g/dL, HCT 55%, RBC 6.6 million/μL, WBC 20,000/μL, and troponin 70 ng/L. ABG values 7.40/27/53/17, and total testosterone level was 1004 ng/dL. CT chest with IV contrast revealed massive bilateral pulmonary emboli with right heart strain. Lower extremity doppler ultrasound demonstrated a DVT in the right posterior tibial vein. The patient underwent catheter-directed thrombolysis via EKOS procedure and was subsequently transitioned to a DOAC. Given the diagnosis of VTE, TRT was discontinued permanently. Discussion: Testosterone has well-documented erythropoietic effects, which can contribute to erythrocytosis (HCT > 54%) and increased blood viscosity, thereby raising the risk of VTE. According to the Endocrine Society guidelines, TRT should be withheld if HCT exceeds 54%, and to be resumed only after HCT returns to the normal range, typically at a lower dose. Additionally, therapeutic phlebotomy—in which one unit of blood (500 mL) is removed at regular intervals—is an effective strategy for managing testosterone-induced erythrocytosis. Per the American Urological Association guidelines, total testosterone and CBC should be measured every 6-12 months during therapy. Conclusion: Erythrocytosis is a well-recognized adverse effect of TRT, requiring regular monitoring of CBC and serum testosterone levels. If HCT exceeds 54%, the TRT dose should be adjusted or temporarily discontinued, and therapeutic phlebotomy may be considered to reduce the risk of VTE. Presentation: Sunday, July 13, 2025