Treatments for priapism in boys and men with sickle cell disease.

BACKGROUND

Sickle cell disease comprises a group of genetic haemoglobin disorders. The predominant symptom associated with sickle cell disease is pain resulting from the occlusion of small blood vessels by abnormally 'sickle-shaped' red blood cells. There are other complications, including chronic organ damage and prolonged painful erection of the penis, known as priapism. Severity of sickle cell disease is variable, and treatment is usually symptomatic. Priapism affects up to half of all men with sickle cell disease, however, there is no consistency in treatment. We therefore need to know the best way of treating this complication in order to offer an effective interventional approach to all affected individuals.

OBJECTIVES

To assess the benefits and risks of different treatments for stuttering (repeated short episodes) and fulminant (lasting for six hours or more) priapism in sickle cell disease.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also searched trial registries.Date of the most recent search of the Group's Haemoglobinopathies Trials Register: 15 September 2017.Date of most recent search of trial registries and of Embase: 12 December 2016.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials comparing non-surgical or surgical treatment with placebo or no treatment, or with another intervention for stuttering or fulminant priapism.

DATA COLLECTION AND ANALYSIS

The authors independently extracted data and assessed the risk of bias of the trials.

MAIN RESULTS

Three trials with 102 participants were identified and met the criteria for inclusion in this review. These trials compared stilboestrol to placebo, sildenafil to placebo and ephedrine or etilefrine to placebo and ranged in duration from two weeks to six months. All of the trials were conducted in an outpatient setting in Jamaica, Nigeria and the UK. None of the trials measured our first primary outcome, detumescence but all three trials reported on the reduction in frequency of stuttering priapism, our second primary outcome. No significant effect of any of the treatments was seen compared to placebo. Immediate side effects were not found to be significantly different from placebo in the two trials where this information was reported. We considered the quality of evidence to be low to very low as all of the trials were at risk of bias and all had low participant numbers.

AUTHORS' CONCLUSIONS: There is a lack of evidence for the benefits or risks of the different treatments for both stuttering and fulminant priapism in sickle cell disease. This systematic review has clearly identified the need for well-designed, adequately-powered, multicentre randomised controlled trials assessing the effectiveness of specific interventions for priapism in sickle cell disease.