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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
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