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Haemoglobinopathies 37
Genitourinary Manifestations Surgery should be considered only if these measures are unsuccessful.
The most common genitourinary manifestations of sickle cell disease The aim of the surgery is to allow the blood from the engorged corpora
are haematuria, urinary tract infection, and priapism. The haematuria is cavernosa to return to the systemic circulation, most commonly via the
often painless and is thought to result from microinfarctions of the renal corpus spongiosum. A cavernoglanular shunt is the easiest to perform
papillae. Management is predominantly conservative. and has the fewest complications. It can be performed with a large
Urinary tract infection (UTI) is more common in patients with SCD biopsy needle (Winter shunt) or a scalpel (Ebbehøj shunt) inserted
compared to the general population. The reason for this is remains percutaneously through the glans. It can also be performed by excising
unclear, but children found to have a UTI should undergo the same a piece of the tunica albuginea at the tip of the corpus cavernosum
careful urological evaluation as nonsickle children. (Al-Ghorab procedure). If such measures fail to achieve detumescence,
Priapism is a well-recognised complication of SCD and can be a more proximal procedure to create a cavernospongiosal shunt
challenging to manage. The condition involves prolonged and painful (Quackel’s procedure) or to anastomose the saphenous vein to one of
penile erection, which can lead to irreversible fibrosis and impotence if the corpora cavernosa (Grayhack procedure) may be warranted.
it persists. About 90% of cases lasting longer than 24 hours have been Recurrent priapism is a common problem, and much effort has been
associated with subsequent erectile dysfunction. Priapism occurs most focused on developing a preventive therapy. Gonadotropin-releasing
commonly in children aged 5–13 years (and in adults aged 21–29 years) hormone analogues and, more recently, 5α-reductase inhibitors appear
and affects 28% of the male paediatric sickle population. The majority to be effective in controlling recurrent priapism, but they have
of children presenting with priapism have sickle cell disease. significant side effects and are not currently licensed for use in children.
The most important history to obtain in a patient presenting with Phosphodiesterase inhibitors are also under evaluation.
priapism pertains to the duration of the current episode and to previous Skin
episodes and their treatment. Alternative causes of priapism, including Leg ulcers are less common in children than in adults and affect approx-
trauma, drugs, and malignancy, should be excluded. imately 3% of patients between the ages of 10 and 19 years with sickle
Examination generally demonstrates rigid corpora cavernosa with a cell anaemia. The ulcers occur spontaneously or as a result of local trau-
soft glans penis and corpus spongiosum. Involvement of the glans can ma with subsequent infection and skin necrosis, but no specific organ-
suggest corporeal infarction. isms have been incriminated. The majority of ulcers are located on the
Investigations should seek to establish or exclude the diagnosis of a lower leg (Figure 7.2); they can also involve the dorsum of the foot and,
haemoglobinopathy in all cases of priapism if this is not already known. more rarely, the sole. Ulcers typically persist for prolonged periods of
Many centres recommend blood gas analysis of blood aspirated from time and take up to 16 times longer to heal than venous ulcers.
the corpus cavernosum to exclude nonischaemic causes of priapism. Surgical intervention can be required to debride infected necrotic
Compared to the ischaemic, low-flow priapism most typical in SCD, ulcers or for skin grafting in intractable cases. Various techniques have
nonischaemic priapism is a high-flow state with causes that include been deployed, including myocutaneous flaps and split thickness skin
cavernous artery fistulas. It is normally relatively pain-free and will grafts but, as with other surgery in this population, such procedures are
often resolve without treatment. In ischaemic priapism, aspirated plagued by a poor success rate.
cavernosal blood is expected to appear dark in colour with an oxygen
saturation of less than 4 kPa (30 mm Hg) and a pH < 7.25. Where the
resources are available, this analysis can be supplemented by colour
duplex ultrasonography.
The evidence base for the management of priapism is poor; as a
result, considerable variation exists in current management practices.
The following discussion is derived largely from the American
Urological Association guidelines, which are based on a review of the
limited evidence and consensus opinion.
Initial management for all sickle patients presenting with priapism
should involve analgesia and hydration. In the past, additional
measures, including ice packs, heat packs, and spinal anaesthesia with
hypotension, have been advocated, but these measures are now thought
to be counterproductive. The role for blood transfusion in this setting, Figure 7.2: Leg ulcer in a patient with sickle cell disease.
although commonly used, is unproven, and in some cases, transfusion
has been associated with serious adverse effects.
Priapism that persists for greater than 4 hours requires urgent focal Surgical Manifestations of the Thalassaemias
treatment that should be carried out in conjunction with the systemic Compared to sickle cell disease, there are relatively few surgical mani-
treatments described above. The initial intervention can be either a festations of the thalassaemias. As in SCD, chronic haemolysis can lead
therapeutic aspiration of corporeal blood or an intracavernous injection to gallstone formation and symptomatic gallstone disease may require
of a sympathomimetic agent. Both procedures can be carried out under cholecystectomy. Splenectomy is sometimes carried out to treat painful
local anaesthetic, following a dorsal nerve block or a penile shaft block. splenomegaly or hypersplenic pancytopaenia; it can also be in used to
A therapeutic aspiration is often carried out first, using an 18- or decrease a patient’s transfusion requirement.
19-gauge butterfly needle inserted into either corpora cavernosa. Postoperative Complications
Blood can then be aspirated, accompanied by irrigation with saline if
so desired. If this procedure fails to achieve detumescence, it should Patients with sickle cell disease clearly experience a higher rate of
be followed by the intracavernous administration of phenylephrine, postoperative complications than the general population. Observed
an α-1 adrenergic agonist. Depending on the age of the child, a small complications include the acute chest syndrome, painful vaso-occlusive
quantity of the drug diluted in normal saline can be injected with careful crises, neurological events, acute kidney injury, and postoperative
monitoring for any side effects including hypertension or arrhythmias. infections. The high postoperative complication rate has traditionally
This can be repeated every 3–5 minutes, as required, for approximately been attributed to unfavourable intraoperative conditions precipitating
1 hour before an assessment of the treatment’s efficacy is made. erythrocyte sickling and leading to vascular occlusion and subsequent