Source:http://linkedlifedata.com/resource/umls/id/C0033117
MSH: A prolonged painful erection that may lasts hours and is not associated with sexual activity. It is seen in patients with SICKLE CELL ANEMIA, advanced malignancy, spinal trauma; and certain drug treatments.,NCI: Persistent and usually painful erection that lasts for at least four hours, in the absence of physical or psychological stimulation. It may be caused by hematologic disorders including sickle cell disease and leukemia, spinal cord injuries, and medications.