Winning Abstracts from the 2010 Medical Student Abstract Competition: Priapism: A Rare Presenting Feature Of Chronic Myeloid Leukemia
Author: Michael McNeal, MD, recent graduate of Texas A&M University System Health Science Center
Priapism is the persistent abnormal erection of the penis without accompanying sexual desire. It is normally classified into idiopathic, the more common type, and secondary, due to an underlying cause. Secondary causes of priapism include disorders such as sickle cell anemia, trauma, leukemia, cancerous invasion of the penis, drugs, and alcohol ingestion. Priapism is further defined as either low-flow (ischemic) or high-flow (non-ischemic). Priapism secondary to chronic myelogenous leukemia is an ischemic or low-flow process that is a urologic emergency. The most common complication is impotence, the incidence of which increases with the amount of time elapsing prior to treatment.
A 21 year-old African American male with no history of sickle cell disease presented to the emergency room with persistent priapism lasting 36 hours. Thirty-six hours prior to admission he was asymptomatic and engaged in successful intercourse. Afterwards, the erection did not resolve and approximately 4 hours later it became painful. The patient endured the pain into the next day. On the morning of admission he awoke with increased pain and a continued erection. He had two similar episodes occurring weeks and months prior that had spontaneously resolved. He denied the use of medications or illegal drugs, fevers, night sweats, weakness, fatigue, abdominal pain, fullness, weight loss, and early satiety. Phenylephrine was administered and the patient underwent irrigation and evacuation without resolution of the erection. The patient was taken to the operating room where a glans-corporal shunt was done resulting in improvement but not resolution of the erection. Lab work drawn in the ER revealed a hemoglobin of 9.7 g/dl, platelets of 267,000 g/dl, and a white blood count of 205,000 g/dl with a differential of 54% granulocytes, 9% bands, 11% lymphocytes 0% monocytes, 0% eosinophils, 1% basophils, 5% metamyelocytes, 12% myelocytes, and 1% promyelocytes. A bone marrow biopsy was consistent with chronic myelogenous leukemia and the diagnosis was confirmed by FISH for t(9;22). The patient was started on hydroxyurea and imatinib. His white count dropped to 92,700 and the patient was discharged with outpatient follow-up with both oncology and urology. Within seven days his white count had decreased further to 22,400. His priapism resolved shortly after discharge from the hospital.
Priapism is a rare feature of chronic myeloid leukemia occurring in 1-2% of males. Hyperleukocytosis causes microaggregation, resulting in sludging and stasis of blood within the veins. The most common long-term complication is a thrombosis in the corpora cavernosa accompanied by fibrosis and impotence. The timing of treatment for this condition is crucial with ideal treatment occurring in the first 24 hours.