Narrative Review

Pathogenesis, Diagnosis, and Treatment of Sleep-Related Painful Erection

Yutao Wang; Jianzhong Zhang; Hongjun Li


Transl Androl Urol. 2021;10(12):4422-4430. 

In This Article

Diagnosis of SRPE

Clinical Characteristics

Patients with SRPE often have the clinical characteristics of repeated waking during REM sleep accompanied by painful erections. Due to the lack of literature support, the effective duration of treatment for the disease is usually 1–3 months, and long-term observation is rare; erections monitored during waking, during intercourse, and during NREM are painless; it is generally believed that the sexual refractory period after ejaculation can make re-erections difficult, and daytime intercourse and ejaculation can inhibit nocturnal erections, but this rule is not followed in SRPE. According to current reports, there is no obvious relationship between the occurrence of SRPE and sexual intercourse, and only one report found the even presence of SRPE after sexual intercourse;[1] each episode of pain lasts from minutes to hours; after being awake or urinating, the symptoms may partially abate; the frequency of episodes ranges from one per hour to several times per night; there is no history of sleep disorders or abnormalities; physical examination and auxiliary examinations of the urinary system and nervous system are unremarkable; no evidence of urinary tract infection; serum prostate-specific antigen and testosterone are within the normal range; the disease occurs at all ages, with an average age of onset of 40 years; there are psychological symptoms such as anxiety, nervousness, irritability, and daytime fatigue; color Doppler ultrasound of the penis, prostate, and kidneys show no abnormalities; the International Erectile Function Score and Nocturnal Penile Erectile Measurements indicates varying degrees of erectile dysfunction; and the intensity of penile erection during pain is grade III–IV.[33]

Differential Diagnosis of SRPE

SRPE needs to be differentiated from priapism, which is a persistent, often painful penile erection that lasts more than 4 hours and has nothing to do with sexual stimulation. Priapism is classified as ischemic penile priapism, non-ischemic penile priapism, and recurrent penile priapism.[34]

In ischemic penile priapism, the cavernous body is stiff, the glans and cavernous body are relaxed, and there is interstitial pressure and damage to the microvessels leading to penile fascial compartment syndrome. Color Doppler ultrasound reveals no blood flow in the cavernous arteries, while body fluid blood gas analysis reveals pO2<30 mmHg, pCO2 >60 mmHg, and pH <7.25.[34] Compared with patients with SRPE, stuttering priapism episodes of ischemia are for the most transient and self-remitting but this priapism is considering harboring of major ischemic priapism. Nearly 30% of patients suffering of stuttering priapism evolve to major episodes of ischemic priapism.[34]

Non-ischemic penile priapism is most often caused by penile, perineal, or pelvic trauma, with laceration of cavernous arterioles leading to the formation of arteriole-sinus fistulas, and is often delayed by a few days.

Recurrent priapism is characterized by long-term periodic erection episodes that are sometimes painful, usually occurring during sleep or sexual stimulation, and may subside spontaneously. It is a common complication of sickle cell disease, caused by microvascular occlusion secondary to hemolysis and stasis.[35–37]