Priapism etiology

Van der Horst C, Stuebinger H, Seif C et al (2003) Priapism-etiology, pathophysiology and management. Int Braz J Urol 29 391-400... 

Although intracavernosal alprostadil injections are effective independent of the etiology for erectile dysfunction, these fail in one-third of patients. Also, they should be used cautiously in patients at risk of priapism, which includes those with sickle cell disease or lymphoproliferative disorders. 

The clinical presentation of these two types of priapism is different. HFP is often seen after an acute injury, and the onset can be delayed. This delayed onset may be due to initial vessel spasm, hemostasis with clot formation or a compressing hematoma. Reabsorption of this clot or hematoma is the mechanism for the late onset. The HFP is often less tumescent when compared with venous priapism. Priapism secondary to arterial causes maybe, as mentioned before, significantly less painful than venous priapism and is not considered as an emergency. The major etiology of HFP is trauma, especially in children or young adults in older men, HFP is a rare event mainly caused by malignancy [2]. High-flow priapism in acute lymphatic leukaemia has also been reported [3]. 

The etiology of priapism has been traditionally divided into primary or idiopatic and secondary to some other condition or disease process. However, in accordance with Pryor (2004), for the purposes of clinical management, it is appropriate to distinguish between high-flow, low-flow, and recurrent or stuttering priapism. 

POHL et al. (1986) evaluated various etiologies for priapism in a study of 230 single case reports in the literature idiopathic causes comprised one-third of the cases, whereas 21% were attributed to alcohol abuse or medications. 

Examples of neurologic etiologic factors include priapism in patients with degenerative stenosis of the lumbar canal, priapism secondary to cauda equine syndrome and herniated disk (Baba et al. 1995). 

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