A painfull erection, lasting for more than 4 hours in the absence of sexual activity is called priapism. It is an emergency condition in urology and requires swift diagnosis and treatment.
There are four types of priapism:
1. Ischemic type, venooclusive with low blood flow. This one is the most commonly diagnosed in childre. It is painflull. The corpora cavernosa ara affected, while the glans and corpus spongiosum of the urethra are soft. It cal lead to serious consequences because ischemia affects corpora cavernosa, causing their fibrosis (in untreated condition). Not the cause, but the starting moment can be masturbation or night erection.
2. Intermitent, periodic priapism – recurrent unwanted, painful erection which usually subside. This group of patients are in risk of finally ending with true ischemic priapism. It is common in people with sickle-cell disease and impedes the quality of life.
3. High-flow priapism is caused by high arterial flow and is not painful. In children pressing the perineum can the condition for a while. This form is much less common then ischemic one.
4. Rare neonatal form – this can last even for a couple of days. The blood flow through corpora cavernosa is preserved and all described cases and spontaneously and happily. Maby it is caused by policythemia, which is normal in this moment of life
The causes of all described cases are sickle-cell disease – 65%, leukemia 10%, trauma 10%, idiopathic 10% and pharmacologically induced 5%. In Polish conditions sickle-cell disease is almost absent, so we must always think about hematologic background of priapism. The peak of this is the 5th decade of life, though is not uncommond in children also.
Erections are natural phenomenon in children since neonatal period and are diven by autonomic reflexes. We can notice them during bath, diaper change, bladder catheterisation and when the baldder is full. These should not be mistaken for priapism.
Low-flow priapism can lead to necrosis of corpora cavernosa with their fibrosis, malformation and shortening of penis and loss or disfunction of erection.
The most common cause of high flow priapism is trauma of the penis or perineum for example during sexual activity or in saddle or bike. Rupture of afferent arterioles in corpora cavernosa leads to formation of arterio-venous fistules. But still some cases are idiopathic.
Priapis is an emergency condition ad requires fast diagnosis and treatment. Differentiation of high and low-flow forms is crucial. It is belived, that after 48 hours of ischemia the damage of corpora cavernosa is irreversible and leads to their fibrosis. Differential diagnosis is based on patients history (trauma in low-flow priapism), clinical signs (ischemic form is painfull and penis tends to be harder), examining flow in doppler ultrasound and assesment of blood gases in blood taken from corpora cavernosa – usually in general anesthesia.
Traditional, home based methods that sometimes can relieve priapism are: extensive physical effort (running the stais for example), ejaculation, micturition and cold bath.
General anesthesia with ketamine in many cases ceases low-flow priapism epizodes, thanks to its special properties in this respect. After induction of anesthesia blood samples should be takes by puncture of corpora cavernosa for blood gases analysis. If anesthesia alone does not bring success the dark desaturated blood should be aspirated from lateral regions of corpora cavernosa, then they ought to be irrigated with warm saline isotonic solution. After that diluted adrenaline or phenylephrine can be injected into corpora cavernosa. In few resistant cases surgical treatment can be considered. It can be creastion of fistulas between corpora cavernosa and corpus spongiosum of the glans (Winter’s method) or corpus spongiosum of urethra (Quackel’s method). In adult patients, after long lasting low-flow priapism episode, one can consider implanting protheses of corpora cavernosa.