Priapism & sickle cell

What priapism is

Priapism is a prolonged erection that persists beyond, or occurs without, sexual stimulation. It is not a sign of sexual health — it is a circulatory problem in which blood cannot leave the penis, and the trapped blood becomes progressively starved of oxygen and acidic, damaging the smooth muscle of the erectile tissue.

The three types

• Ischaemic (low-flow) priapism — the common and dangerous form. The penis is rigid and usually painful, and blood is not draining. This is the true emergency.
• Non-ischaemic (high-flow) priapism — usually follows trauma to the perineum or genitals, creating an abnormal arterial connection. The erection is typically partial and painless, and it is not an emergency, though it does need specialist assessment.
• Recurrent ischaemic (stuttering) priapism — repeated self-limiting episodes, often at night, most commonly seen in sickle cell disease. Each episode causes incremental damage, and this pattern very often precedes a major episode.

Priapism in sickle cell disease

Priapism is one of the most under-discussed complications of sickle cell disease. A substantial proportion of men and boys with sickle cell disease experience it, frequently starting in childhood or adolescence, and many never mention it — through embarrassment, or because nobody has ever asked or explained that it is a recognised part of the condition.

The consequences of not raising it are significant. Repeated stuttering episodes progressively scar the erectile tissue, and by adulthood many affected men have permanent erectile dysfunction that could have been reduced with earlier management. Recognising and treating stuttering priapism early is therefore the single most valuable intervention.

Other causes

• Intracavernosal injection therapy for erectile dysfunction, at too high a dose
• Medications, including some antidepressants, antipsychotics and blood pressure drugs
• Recreational drugs, including cocaine and excess alcohol
• Other blood disorders, including thalassaemia and leukaemia
• Pelvic or genital trauma
• Rarely, tumours affecting pelvic drainage

How priapism is managed

Acute ischaemic priapism is treated urgently by aspirating blood from the erectile tissue and injecting a medication to constrict the vessels. If this fails, a surgical shunt is created to allow drainage. Where an episode has been very prolonged and the tissue is not salvageable, early insertion of a penile prosthesis is sometimes recommended, because scarring makes later implantation considerably more difficult.

Recurrent stuttering priapism is managed differently — the aim is prevention. This may involve optimising sickle cell treatment with the haematology team, hormonal or other preventive medication, self-administered rescue treatment for men who have been taught to use it, and clear written guidance about when to attend hospital. Non-ischaemic priapism often resolves without intervention and is managed conservatively, with embolisation reserved for persistent cases.

My practice in this area

I established the joint sickle cell urology clinic at Guy's Hospital in 2013 with consultant haematologist Rachel Kesse-Adu, managing patients with sickle cell priapism. The clinic has since expanded to King's College Hospital and the Evelina Hospital. I have been a UK National Haemoglobinopathy Advisory Panel expert member for sickle cell disease since 2020, and I am currently involved in writing national practice guidelines for sickle cell priapism.

With Dr Kesse-Adu, the Sickle Cell Society UK and industry partners, I helped produce an educational animation about sickle cell priapism aimed at children with sickle cell disease and their carers. It won three awards at the 77th Annual Association of Medical Illustrators Conference in 2023 — the Award of Excellence in Education, the Social Impact Award and the Member's Choice Award — and is hosted on both the BAUS and Sickle Cell Society UK websites. You can watch it on the videos page.