AKT · Renal & urology/Urological cancer & LUTSlow yield

Erectile dysfunction & priapism

ED = failure to achieve/maintain an erection (vascular/neurogenic/endocrine/psychogenic/drugs); priapism = prolonged unwanted erection

Overview

Two ends of the erectile spectrum. Erectile dysfunction (ED) is the persistent inability to achieve or maintain an erection for satisfactory sex — frequently an early marker of cardiovascular disease or diabetes, so it warrants CV-risk assessment. Priapism is the opposite: a prolonged (>4 h) unwanted erection that is a urological EMERGENCY because the ischaemic form causes corporal necrosis and permanent impotence.

Recognise

ED — organic clues: gradual onset, absent morning/spontaneous erections, vascular risk factors (diabetes, smoking, hypertension), drugs (beta-blockers, thiazides, SSRIs, antipsychotics), endocrine (low testosterone, hyperprolactinaemia)
ED — psychogenic clues: sudden onset, situational, preserved morning erections, relationship/anxiety context; young man
Priapism: painful persistent erection >4 h with a soft glans (ischaemic/low-flow — the emergency); causes — sickle cell disease, drugs (trazodone, intracavernosal agents, recreational), haematological malignancy, spinal cord injury

Red flags

Priapism >4 h = urological EMERGENCY → aspiration ± intracavernosal phenylephrine without delay (ischaemia → permanent erectile dysfunction)
New ED is a sentinel marker of cardiovascular disease/diabetes → assess and modify CV risk; don't co-prescribe a PDE5 inhibitor with nitrates

Differentials & how to tell them apart

Psychogenic vs organic EDpreserved morning erections + sudden situational onset = psychogenic; absent morning erections + vascular risk = organic

Hypogonadism / hyperprolactinaemialow testosterone / raised prolactin — endocrine cause, cross-ref endocrine

Peyronie's diseasepenile curvature/fibrous plaque causing painful/difficult intercourse

Ischaemic vs non-ischaemic priapismischaemic (painful, rigid, low-flow, hypoxic gas) = emergency; non-ischaemic (high-flow, post-traumatic, not painful) less urgent

Investigations

ED: history (organic vs psychogenic), examination (peripheral pulses, genitalia, prostate), bloods — fasting glucose/HbA1c, lipids, morning testosterone (± prolactin/LH/FSH and TFTs if low); assess cardiovascular risk. Priapism: cavernosal blood gas (ischaemic = hypoxic/acidotic, low-flow), FBC/sickle screen, identify the precipitant.

Management

ED → CV-risk assessment + PDE5 inhibitor (not with nitrates); priapism → emergency aspiration ± phenylephrine

1ED: distinguish organic from psychogenic (morning erections, onset, risk factors); check glucose/lipids/morning testosterone and assess cardiovascular risk; treat reversible causes and offer a PDE5 inhibitor.Gate: Do NOT co-prescribe a PDE5 inhibitor with nitrates/nicorandil (severe hypotension); new ED is a sentinel marker of cardiovascular disease — investigate and modify risk.
2Priapism >4 h is a urological EMERGENCY → cavernosal blood gas, then aspiration ± intracavernosal phenylephrine (and treat the cause — sickle cell, culprit drug); surgical shunt if refractory. Delay risks permanent impotence.

ED: address CV risk + lifestyle; PDE5 inhibitor (sildenafil/tadalafil) first-line — treat reversible causes/drugs; PDE5 inhibitor is first-line — CONTRAINDICATED with nitrates/nicorandil (profound hypotension)

ED: treat the underlying cause — testosterone replacement for confirmed hypogonadism, treat hyperprolactinaemia, psychosexual therapy for psychogenic ED; vacuum devices/intracavernosal/prosthesis if refractory

Priapism: aspiration of cavernosal blood ± intracavernosal phenylephrine — the emergency treatment of ischaemic priapism; treat the cause (sickle cell crisis management, stop the culprit drug)

Priapism refractory → surgical shunt — if aspiration/phenylephrine fail

Key points

ED: organic (gradual, NO morning erections, vascular/diabetic/drug/endocrine) vs psychogenic (sudden, situational, morning erections preserved) → PDE5 inhibitor (NEVER with nitrates) + CV-risk assessment (ED is a sentinel CV marker). Priapism >4 h = EMERGENCY (sickle cell, trazodone) → aspiration ± phenylephrine before ischaemia causes permanent impotence.

Monitor & prognosis

ED: response/CV risk factors; priapism: detumescence, recurrence, the underlying cause.

ED treatable and a useful CV warning sign; ischaemic priapism risks permanent impotence if not treated promptly.

Source: NICE CKS (ED); BAUS (priapism); cross-ref cardiovascular/endocrine, child_health (sickle cell)