Editing Priapism (section)

== Diagnosis and Evaluation ==

* See [https://www.auanet.org/documents/Guidelines/PDF/priapism/NIP%20JU%20SUMMARY%20Figure%20One%20Diagnosis%20of%20Priapism.pdf AUA/SMSNA Guideline Flowchart on Diagnosis of Priapism]

=== UrologySchool.com Summary ===
* '''<span style="color:#ff0000">Recommended</span>'''
**'''<span style="color:#ff0000">History and Physical Exam</span>'''
** '''<span style="color:#ff0000">Labs (2)</span>'''
**# '''<span style="color:#ff0000">Corporal blood gas</span>'''
* '''<span style="color:#ff0000">Optional</span>'''
**'''<span style="color:#ff0000">Labs (3)</span>'''
**#'''<span style="color:#ff0000">CBC</span>'''
**#'''<span style="color:#ff0000">Hemoglobin electrophoresis</span>'''
**#'''<span style="color:#ff0000">Screening for psychoactive drugs and urine toxicology</span>'''
**'''<span style="color:#ff0000">Imaging</span>'''
***'''<span style="color:#ff0000">Penile duplex Doppler ultrasonography</span>'''
****When the diagnosis of acute ischemic versus non-ischemic priapism is indeterminate

=== History and Physical Exam ===

* '''In the majority of cases, the differentiation of acute ischemic priapism versus non-ischemic priapism may be made using only the history and physical exam.'''  
** In cases where the subtype is indeterminate, additional testing may be warranted. 

==== History ====
* '''<span style="color:#ff0000">Signs and Symptoms</span>'''
**'''<span style="color:#ff0000">Sexual history</span>'''
***'''Duration of erection, presence of pain'''
***'''Baseline erectile function'''
* '''<span style="color:#ff0000">Risk factors</span>'''
**'''<span style="color:#ff0000">Medical history</span>'''
*** '''Personal or family history of sickle cell disease, hemoglobinopathies, hypercoagulable states'''
***'''Pelvic, genital, or perineal trauma, especially a perineal straddle injury'''
***'''Previous episodes of priapism and method of treatment'''
** '''<span style="color:#ff0000">Medications that might have precipitated the episode</span>'''
*** '''Use of any erectogenic therapies (both prescription and nutritional supplements)'''
*** '''Use of recreational drugs'''

==== Physical Exam ====
* '''<span style="color:#ff0000">Genitalia</span>'''
**'''<span style="color:#ff0000">The corpora cavernosa are typically affected while the corpus spongiosum and the glans penis are not</span>'''
**'''<span style="color:#ff0000">In ischemic priapism, the corpora cavernosa are often fully rigid and tender</span>'''
**'''<span style="color:#ff0000">In non-ischemic priapism, the corporal cavernosa will be tumescent, partially erect, but not completely rigid. The penis is also unlikely to be tender</span>'''
*'''<span style="color:#ff0000">Abdominal, pelvic, and perineum</span>'''
**'''May reveal evidence of trauma or malignancy.'''

=== Laboratory ===

* '''<span style="color:#ff0000">Corporal blood gas by aspiration</span>'''
** '''<span style="color:#ff0000">Should be obtained in the emergency evaluation of priapism</span>[https://pubmed.ncbi.nlm.nih.gov/35536142/ ★]'''
***Clinical situations where a blood gas may be omitted at the clinician’s discretion (3):
***#Priapism induced by in-office or at home ICI therapies
***#Cases of recurrent ischemic priapism (i.e., SCD)
***#When the diagnosis is abundantly clear by history and examination alone
**Most common diagnostic methods of distinguishing acute ischemic priapism from non-ischemic priapism when the diagnosis cannot be made by history alone
**Blood aspirated from the corpus cavernosum in patients with acute ischemic priapism is hypoxic (dark red), while corporal blood in NIP patients is normally oxygenated (bright red)

{| class="wikitable"
!Source
!<span style="color:#ff0000">PO2 (mm Hg)</span>
!<span style="color:#ff0000">PCO2 (mm Hg)</span>
!<span style="color:#ff0000">pH</span>
|-
!Normal arterial blood (room air)
|'''>90'''
|'''<40'''
|'''7.40'''
|-
!Normal mixed venous blood (room air)
|40
|50
|7.35
|-
!<span style="color:#ff0000">Ischemic priapism (first corporal aspirate)</span>
|<span style="color:#ff0000">'''<30'''</span>
|<span style="color:#ff0000">'''>60'''</span>
|<span style="color:#ff0000">'''<7.25'''</span>
|}

* '''CBC'''
** May identify elevated white blood cell counts, potentially identifying cases where priapism is due to underlying malignancy (e.g., leukemia).  
**Among men with sickle cell disease, acute ischemic priapism is associated with lower hemoglobin and elevated lactate dehydrogenase, bilirubin, aspartate aminotransferase, reticulocyte count, white blood cells, and platelet counts. 
**Platelet and eosinophil counts may also be elevated in men with acute ischemic priapism. 
* '''Hemoglobin electrophoresis and other sickle cell testing'''
** '''May be appropriate in select clinical scenarios and based on underlying clinical suspicion (e.g., patient race)'''
***In most cases, most men with sickle cell disease have been diagnosed previously.  
****The yield of identifying men with previously undiagnosed SCD among a cohort of men presenting with priapism is not well established.  
*'''Urine and serum toxicology panels'''
** A thorough medication and social history may provide enough information to determine the underlying cause of the priapism without collection of these studies.
***Testing for potential substances may have a high rate of false negativity, particularly with synthetic and otherwise altered versions of common illicit substances
*'''While CBC, hemoglobin electrophoresis, and toxicology panels may contribute to the identification of underlying cause, they often will not be used to guide treatment of the acute presentation'''

=== Imaging ===

==== Color Doppler US ====
* '''<span style="color:#ff0000">Indications</span>'''
**'''<span style="color:#ff0000">Should not be incorporated into the acute evaluation and management of priapism in the emergency department by non-urologist specialists</span>[https://pubmed.ncbi.nlm.nih.gov/35536142/ ★]'''
***Not the primary way to diagnose priapism
**'''<span style="color:#ff0000">May be utilized in less clearly delineated cases to differentiate between acute ischemic priapism and non-ischemic priapism</span>[https://pubmed.ncbi.nlm.nih.gov/35536142/ ★]'''
*Findings[https://pubmed.ncbi.nlm.nih.gov/34495686/ §]
**Acute ischemic priapism
***Bilateral absence of flow through the cavernosal arteries
***Peak systolic flows <50 cm/sec
***Mean velocity <6.5 cm/sec
***Diastolic reversal (i.e., negative end diastolic velocities)
**Non-ischemic priapism
***Peak systolic velocities of >50 cm/sec.
***In the non-acute setting, may identify anatomical abnormalities, such as a cavernous artery fistula or pseudoaneurysm in patients who already have been diagnosed with non-ischemic priapism. 
****These abnormalities may occur following a straddle injury or direct scrotal trauma and are, therefore, most often found in the perineal portions of the corpora cavernosa.
*Use is limited by
**Number of specialists who can currently perform the procedure
**Equipment might not be readily available
==== Pelvic MRI ====
* Likely does not have a role in the initial diagnostic and treatment phase of priapism'''<span style="color:#ff0000">[https://pubmed.ncbi.nlm.nih.gov/35536142/ ★]</span>'''
*'''Can be used to demonstrate:'''
*# '''A well-established arteriolar-sinusoidal fistula'''
*# '''Presence and extent of tissue thrombus'''
*# '''Corporal smooth muscle infarction'''
*# '''Corporal malignancy or metastasis'''

==== Penile arteriography ====
* Too invasive as a diagnostic procedure to differentiate ischemic from non-ischemic priapism