Prevalence of priapism in children and adolescents with sickle cell anemia.

A questionnaire survey was conducted of patients with homozygous sickle cell anemia (Hb SS) and sickle cell beta(0)-thalassemia (Hb S-beta(0)) between 5 and 20 years of age to determine the prevalence and characteristics (number of episodes, timing, duration, cause, or precipitating event) of priapism. Ninety-eight male patients or their parents were surveyed by the same male investigator using a structured verbal interview, which was modified according to the age of the patient. Ninety-four patients had Hb SS and four Hb S-beta(0) thalassemia. Eleven (11%) patients were known to have experienced priapism previously. In response to the questionnaire, 16 of the remaining 87 (18%) patients reported having had priapism on one or more occasions. The actuarial probability of experiencing priapism by 20 years of age was 89% (+/- 9%). The mean age at the initial episode was 12 years, the mean number of episodes per patient was 15.7 (median, 1; range, 1-100), and the mean duration of an episode was 125 minutes. Episodes typically occurred around 4:00 am, and 75% of the patients surveyed had at least one episode starting during sleep or upon awakening from sleep. The prevalence of priapism in children and adolescents with SCA is much higher than previously described. Since early intervention and treatment may prevent irreversible penile fibrosis and impotence, patients and parents should be educated about this complication in advance of its occurrence.