What are the key history and physical examination findings for priapism?

Key History and Physical Examination Findings for Priapism

A complete medical, sexual, and surgical history combined with focused genital examination are mandatory for all patients presenting with priapism, as these findings directly determine treatment urgency and approach. 1

Essential History Components

The following historical features must be systematically identified in every patient presenting with priapism 1:

Erection Characteristics

• Duration of erection: Critical for determining treatment urgency, as ischemic priapism >4 hours constitutes a urological emergency requiring immediate intervention 2
• Degree of pain: Ischemic priapism typically presents with severe pain and full rigidity, while non-ischemic priapism is painless with partial tumescence 1, 3
• Baseline erectile function: Establishes pre-existing erectile capacity and helps guide counseling about post-treatment outcomes 1

Precipitating Factors

• Drug use: Specifically inquire about intracavernosal injection therapy (e.g., alprostadil, papaverine), phosphodiesterase-5 inhibitors, antipsychotics, antidepressants (particularly SSRIs like paroxetine), antihypertensives, and recreational drugs including cocaine 1
• Trauma history: Perineal straddle injuries or blunt pelvic/genital trauma suggest non-ischemic (high-flow) priapism from arteriovenous fistula formation 1, 4

Underlying Medical Conditions

• Hematologic disorders: Personal or family history of sickle cell disease or trait, thalassemia, leukemia, or other blood dyscrasias 1
• Malignancies: Particularly genitourinary cancers (prostate, bladder, kidney) or hematologic malignancies that can cause priapism through tumor infiltration or hypercoagulability 1
• Previous priapism episodes: History of stuttering/recurrent priapism and what treatments were effective 1

Spinal Cord Injury

• Neurologic trauma: Priapism associated with spinal cord injury is typically non-ischemic and does not require emergency treatment, unlike idiopathic ischemic priapism 5

Critical Physical Examination Findings

The genitalia, perineum, and abdomen must be carefully examined in all cases 1:

Penile Examination

• Corpora cavernosa rigidity: In ischemic priapism, the corpora cavernosa are fully rigid and exquisitely tender, while the corpus spongiosum and glans penis remain soft and uninvolved 1
• Partial vs. complete tumescence: Non-ischemic priapism exhibits partial corporal tumescence without full rigidity, distinguishing it from the complete rigidity of ischemic priapism 1, 3
• Glans and corpus spongiosum: These structures are characteristically spared in both types of priapism, remaining soft even when the corpora cavernosa are rigid 1

Additional Examination Areas

• Perineum: Examine for signs of trauma, hematoma, or masses that might suggest arterial injury 1
• Abdomen: Palpate for masses, organomegaly (splenomegaly in sickle cell disease), or lymphadenopathy suggesting malignancy 1

Diagnostic Testing to Complete the Evaluation

While not strictly "history and physical," these tests are essential immediate adjuncts 1:

Corporal Blood Gas Analysis

• Mandatory in most cases: Should be obtained at initial presentation to definitively distinguish ischemic from non-ischemic priapism 1
• Ischemic priapism values: PO₂ <30 mmHg, PCO₂ >60 mmHg, pH <7.25 (hypoxic, hypercarbic, acidotic) 1, 6
• Non-ischemic priapism values: Similar to normal arterial blood (PO₂ >90 mmHg, PCO₂ <40 mmHg, pH 7.40) 1, 6
• Can be omitted: Only when diagnosis is abundantly clear (e.g., priapism immediately following intracavernosal injection therapy, known recurrent ischemic priapism in sickle cell disease) 1

Common Pitfalls to Avoid

• Delaying corporal blood gas: While history and exam provide strong clues, blood gas analysis is the definitive diagnostic test and should not be delayed when the diagnosis is uncertain 1
• Assuming all priapism is ischemic: Non-ischemic priapism does not require emergency intervention and can be managed conservatively, making accurate differentiation critical 5, 4
• Inadequate drug history: Many medications cause priapism, and patients may not volunteer information about erectile dysfunction treatments or recreational drug use without direct questioning 1
• Missing the 4-hour window: Tissue damage begins as early as 6 hours, and permanent erectile dysfunction becomes highly likely after 36 hours of ischemic priapism 2, 6