Priapism is a condition in which a

penis A penis (plural ''penises'' or ''penes'' () is the primary sexual organ that male animals use to inseminate females (or hermaphrodites) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males d ...

remains erect for hours in the absence of stimulation or after stimulation has ended. There are three types:

ischemic Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...

(low-flow), nonischemic (high-flow), and recurrent ischemic (intermittent). Most cases are ischemic. Ischemic priapism is generally painful while nonischemic priapism is not. In ischemic priapism, most of the penis is hard; however, the

glans penis In male human anatomy, the glans penis, commonly referred to as the glans, is the bulbous structure at the distal end of the human penis that is the human male's most sensitive erogenous zone and their primary anatomical source of sexual ...

is not. In nonischemic priapism, the entire penis is only somewhat hard. Very rarely, clitoral priapism occurs in women.

Sickle cell disease Sickle cell disease (SCD) is a group of blood disorders typically inherited from a person's parents. The most common type is known as sickle cell anaemia. It results in an abnormality in the oxygen-carrying protein haemoglobin found in red b ...

is the most common cause of ischemic priapism. Other causes include medications such as

antipsychotic Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range o ...

s, SSRIs,

blood thinners Anticoagulants, commonly known as blood thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time. Some of them occur naturally in blood-eating animals such as leeches and mosquitoes, where t ...

and prostaglandin E1, as well as drugs such as

cocaine Cocaine (from , from , ultimately from Quechua: ''kúka'') is a central nervous system (CNS) stimulant mainly used recreationally for its euphoric effects. It is primarily obtained from the leaves of two Coca species native to South Am ...

. Ischemic priapism occurs when blood does not adequately drain from the penis. Nonischemic priapism is typically due to a connection forming between an

artery An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pu ...

and the corpus cavernosum or disruption of the

parasympathetic nervous system The parasympathetic nervous system (PSNS) is one of the three divisions of the autonomic nervous system, the others being the sympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part ...

resulting in increased arterial flow. Nonischemic priapism may occur following trauma to the penis or a

spinal cord injury A spinal cord injury (SCI) is damage to the spinal cord that causes temporary or permanent changes in its function. Symptoms may include loss of muscle function, sensation, or autonomic function in the parts of the body served by the spinal co ...

. Diagnosis may be supported by blood gas analysis of blood aspirated from the penis or an

ultrasound Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies fr ...

. Treatment depends on the type. Ischemic priapism is typically treated with a

nerve block Nerve block or regional nerve blockade is any deliberate interruption of signals traveling along a nerve, often for the purpose of pain relief. Local anesthetic nerve block (sometimes referred to as simply "nerve block") is a short-term block, ...

of the penis followed by aspiration of blood from the corpora cavernosa. If this is not sufficient, the corpus cavernosum may be irrigated with cold,

normal saline Saline (also known as saline solution) is a mixture of sodium chloride (salt) and water. It has a number of uses in medicine including cleaning wounds, removal and storage of contact lenses, and help with dry eyes. By injection into a vein i ...

or injected with

phenylephrine Phenylephrine is a medication primarily used as a decongestant, to dilate the pupil, to increase blood pressure, and to relieve hemorrhoids. In the United States, it was previously used orally as an over-the-counter decongestant to relieve na ...

. Nonischemic priapism is often treated with cold packs and compression. Surgery may be done if usual measures are not effective. In ischemic priapism, the risk of permanent scarring of the penis begins to increase after four hours and definitely occurs after 48 hours. Priapism occurs in about 1 in 20,000 to 1 in 100,000 males per year.

Classification

Priapism is classified into three groups: ischemic (low-flow), nonischemic (high-flow), and recurrent ischemic. The majority of cases (19 out of 20) are ischemic in nature. Some sources give a duration of four hours as a definition of priapism, but others give six. "The duration of a normal erection before it is classifiable as priapism is still controversial. Ongoing penile erections for more than 6 hours can be classified as priapism." Priapism in females (continued, painful erection of the

clitoris The clitoris ( or ) is a female sex organ present in mammals, ostriches and a limited number of other animals. In humans, the visible portion – the glans – is at the front junction of the labia minora (inner lips), above the o ...

) is significantly rarer than priapism in men and is known as clitoral priapism or clitorism. It is associated with persistent genital arousal disorder (PGAD). Only a few case reports of women experiencing clitoral priapism exist.

Signs and symptoms

Complications

Because

priapism causes the blood to remain in the penis for unusually long periods of time, the blood becomes deprived of oxygen, which can cause damage to the penile tissue. Such damage can result in

erectile dysfunction Erectile dysfunction (ED), also called impotence, is the type of sexual dysfunction in which the penis fails to become or stay erect during sexual activity. It is the most common sexual problem in men.Cunningham GR, Rosen RC. Overview of ma ...

or disfigurement of the penis. In extreme cases, if the penis develops severe vascular disease, the priapism can result in penile

gangrene Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the gan ...

Low-flow priapism

Causes of low-flow priapism include

sickle cell anemia Sickle cell disease (SCD) is a group of blood disorders typically inherited from a person's parents. The most common type is known as sickle cell anaemia. It results in an abnormality in the oxygen-carrying protein haemoglobin found in red b ...

(most common in children),

leukemia Leukemia ( also spelled leukaemia and pronounced ) is a group of blood cancers that usually begin in the bone marrow and result in high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or ...

, and other blood dyscrasias such as

thalassemia Thalassemias are inherited blood disorders characterized by decreased hemoglobin production. Symptoms depend on the type and can vary from none to severe. Often there is mild to severe anemia (low red blood cells or hemoglobin). Anemia can resul ...

and

multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, ane ...

, and the use of various drugs, as well as cancers. A genome-wide association study on Brazilian patients with sickle cell disease identified four single nucleotide polymorphisms in LINC02537 and

NAALADL2 N-Acetylated Alpha-Linked Acidic Dipeptidase Like 2 (NAALADL2) is a protein, encoded by the gene ''NAALADL2'' in humans. ''NAALADL2'' shares 25%–26% sequence identity and 45% sequence similarity with the glutamate carboxypeptidase II family which ...

significantly associated with priapism. Other conditions such as

Fabry's disease Fabry disease, also known as Anderson–Fabry disease, is a rare genetic disease that can affect many parts of the body, including the kidneys, heart, and skin. Fabry disease is one of a group of conditions known as lysosomal storage disease ...

, as well as neurologic disorders such as

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spin ...

lesions and spinal cord trauma (priapism has been reported in people who have been hanged; see death erection). Priapism can also be caused by reactions to

medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the medical field an ...

s. The most common medications that cause priapism are intra-cavernous injections for the treatment of

( papaverine, alprostadil). Other medication groups reported are antihypertensives,

s (e.g.,

chlorpromazine Chlorpromazine (CPZ), marketed under the brand names Thorazine and Largactil among others, is an antipsychotic medication. It is primarily used to treat psychotic disorders such as schizophrenia. Other uses include the treatment of bipolar di ...

clozapine Clozapine is a psychiatric medication and is the first atypical antipsychotic (also called second-generation antipsychotic). It is primarily used to treat people with schizophrenia and schizoaffective disorders who have had an inadequate resp ...

antidepressant Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness ...

s (most notably trazodone),

anti-convulsant Anticonvulsants (also known as antiepileptic drugs or recently as antiseizure drugs) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of ...

and

mood stabilizer A mood stabilizer is a psychiatric medication used to treat mood disorders characterized by intense and sustained mood shifts, such as bipolar disorder and the bipolar type of schizoaffective disorder. Uses Mood stabilizers are best known for th ...

drugs such as sodium valproate.

Anticoagulants Anticoagulants, commonly known as blood thinners, are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time. Some of them occur naturally in blood-eating animals such as leeches and mosquitoes, where they ...

, cantharides (''Spanish Fly'') and recreational drugs (

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

, heroin and

) have been associated. Priapism is also known to occur from bites of the Brazilian wandering spider.

High-flow priapism

Causes of high-flow priapism include: *blunt trauma to the perineum or penis, with laceration of the cavernous artery, which can generate an arterial-lacunar fistula. *Anticoagulants (heparin and warfarin). *Antihypertensives (i.e., hydralazine, guanethidine and propranolol). *Hormones (i.e., gonadotropin releasing hormone and testosterone).

Diagnosis

The diagnosis is often based on the history of the condition as well as a

physical exam In a physical examination, medical examination, or clinical examination, a medical practitioner examines a patient for any possible medical signs or symptoms of a medical condition. It generally consists of a series of questions about the patient ...

. Blood gas testing the blood from the cavernosa of the penis can help in the diagnosis. If the low-flow type of priapism is present, the blood typically has a low pH, while if the high-flow type is present, the pH is typically normal. Color Doppler

may also help differentiate the two. Testing a person to make sure they do not have a

hemoglobinopathy Hemoglobinopathy is the medical term for a group of inherited blood disorders and diseases that primarily affect red blood cells. They are single-gene disorders and, in most cases, they are inherited as autosomal co-dominant traits. There are tw ...

may also be reasonable.

Ultrasonography

Penile ultrasonography Penile ulltrasonography is medical ultrasonography of the penis. Ultrasound is an excellent method for the study of the penis, such as indicated in trauma, priapism, erectile dysfunction or suspected Peyronie's disease.Originally copied from:CC- ...

with Doppler is the imaging method of choice, because it is noninvasive, widely available, and highly sensitive. By means of this method, it is possible to diagnose priapism and differentiate between its low- and high-flow forms.Originally copied from:

CC-BY A Creative Commons (CC) license is one of several public copyright licenses that enable the free distribution of an otherwise copyrighted "work".A "work" is any creative material made by a person. A painting, a graphic, a book, a song/lyric ...

license In low-flow (ischemic) priapism the flow in the cavernous arteries is reduced or absent. As the condition progresses, there is an increase in echogenicity of the corpora cavernosa, attributed to tissue edema. Eventually, changes in the echotexture of the corpora cavernosa can be observed due to the fibrotic transformation generated by tissue anoxia. In high-flow priapism normal or increased, turbulent blood flow in the cavernous arteries is seen. The area surrounding the fistula presents a hypoechoic, irregular lesion in the cavernous tissue.

Treatment

Medical evaluation is recommended for erections that last for longer than four hours. Pain can often be reduced with a

dorsal penile nerve The dorsal nerve of the penis is the deepest division of the pudendal nerve; it accompanies the internal pudendal artery along the ramus of the ischium; it then runs forward along the margin of the inferior ramus of the pubis, between the superio ...

block or penile

ring block Nerve block or regional nerve blockade is any deliberate interruption of signals traveling along a nerve, often for the purpose of pain relief. Local anesthetic nerve block (sometimes referred to as simply "nerve block") is a short-term block, u ...

. For those with nonischemic priapism, cold packs and pressure to the area may be sufficient.

Pseudoephedrine

Orally administered

pseudoephedrine Pseudoephedrine (PSE) is a sympathomimetic drug of the phenethylamine and amphetamine chemical classes. It may be used as a nasal/sinus decongestant, as a stimulant, or as a wakefulness-promoting agent in higher doses. It was first charac ...

is a first-line treatment for priapism. Erection is largely a parasympathetic response, so the sympathetic action of pseudoephedrine may serve to relieve this condition. Pseudoephedrine is an alpha-agonist agent that exerts a constriction effect on smooth muscle of corpora cavernosum, which in turn facilitates venous outflow. Pseudoephedrine is no longer available in some countries.

Aspiration

For those with ischemic priapism, the initial treatment is typically aspiration of blood from the corpus cavernosum. This is done on either side. If this is not sufficiently effective, then cold

may be injected and removed.

Medications

If aspiration is not sufficient, a small dose of

may be injected into the corpus cavernosum. Side effects of phenylephrine may include:

high blood pressure Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high b ...

, slow heart rate, and

arrhythmia Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults ...

. If this medication is used, it is recommended that people be monitored for at least an hour after. For those with recurrent ischemic priapism,

diethylstilbestrol Diethylstilbestrol (DES), also known as stilbestrol or stilboestrol, is a nonsteroidal estrogen medication, which is presently rarely used. In the past, it was widely used for a variety of indications, including pregnancy support for those with a ...

(DES) or terbutaline may be tried.

Surgery

Distal shunts, such as the Winter's, involve puncturing the glans (the distal part of the penis) into one of the cavernosa, where the old, stagnant blood is held. This causes the blood to leave the penis and return to the circulation. This procedure can be performed by a urologist at the bedside. Winter's shunts are often the first invasive technique used, especially in hematologically induced priapism, as it is relatively simple and repeatable. Proximal shunts, such as the Quackel's, are more involved and entail operative dissection in the

perineum The perineum in humans is the space between the anus and scrotum in the male, or between the anus and the vulva in the female. The perineum is the region of the body between the pubic symphysis (pubic arch) and the coccyx (tail bone), inclu ...

where the corpora meet the spongiosum while making an incision in both and suturing both openings together. Shunts created between the corpora cavernosa and great saphenous vein called a Grayhack shunt can be done though this technique is rarely used. As the complication rates with prolonged priapism are high, early

penile prosthesis A penile implant is an implanted device intended for the treatment of erectile dysfunction, Peyronie's disease, ischemic priapism, deformity and any traumatic injury of the penis, and for phalloplasty or metoidioplasty, including in gender-affi ...

implantation may be considered. As well as allowing early resumption of sexual activity, early implantation can avoid the formation of dense fibrosis and, hence, a shortened penis.

Sickle cell anemia

In sickle cell anemia, treatment is initially with

intravenous fluids Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...

pain medication An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...

, and

oxygen therapy Oxygen therapy, also known as supplemental oxygen, is the use of oxygen as medical treatment. Acute indications for therapy include hypoxemia (low blood oxygen levels), carbon monoxide toxicity and cluster headache. It may also be prophylactic ...

. The typical treatment of priapism may be carried out as well.

Blood transfusions Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but m ...

are not usually recommended as part of the initial treatment, but if other treatments are not effective,

exchange transfusion An exchange transfusion is a blood transfusion in which the patient's blood or components of it are exchanged with (replaced by) other blood or blood products. The patient's blood is removed and replaced by donated blood or blood components. This ...

may be done.

History

Persistent semi-erections and intermittent states of prolonged erections have historically been sometimes called semi-priapism.

Terminology

The name comes from the Greek god

Priapus In Greek mythology, Priapus (; grc, Πρίαπος, ) is a minor rustic fertility god, protector of livestock, fruit plants, gardens and male genitalia. Priapus is marked by his oversized, permanent erection, which gave rise to the medical term ...

( grc, Πρίαπος), a fertility god, often represented with a disproportionately large, permanent erection.

References

External links

Guideline on the Management of Priapism (2003)
- American Urological Association website
The unabridged 275-page version of this guideline.
* {{Male diseases of the pelvis and genitals Penis disorders Medical emergencies Sexual health Wikipedia emergency medicine articles ready to translate