Myomatous erythrocytosis syndrome: a uterine fibroid associated with polycythaemia

Myomatous erythrocytosis syndrome (MES) is a rare form of secondary erythrocytosis seen with myomas. Here, we present a case of a postmenopausal, nulliparous woman in her 50s incidentally found to have asymptomatic erythrocytosis on routine laboratory work. She was found to have an 18.5 cm myoma and after surgical resection, the patient’s haematological values returned to normal ranges after a few weeks. This established the diagnosis as MES. The aetiology of MES continues to remain unknown but is most likely caused by an autonomous production of erythropoietin from the myomatous tissue. This case highlights obtaining a detailed history and physical examination to differentiate between the different causes of erythrocytosis, considering MES as a rare cause of secondary erythrocytosis and to prevent unnecessary procedures such as phlebotomy as surgery is the mainstay of treatment.