Lianne Pickett, Urology ST5 at Great Ormond Street Hospital (GOSH), and Ms Neetu Kumar, Consultant Paediatric Urological Surgeon at GOSH, provide expert insights into the key aspects of paediatric urology.
Curriculum
- Paediatric urology contributes one of the eight stations of the FRCS (Urol) viva. It is a double station, lasting 40 minutes.
- Based on the Intercollegiate Surgical Curriculum Programme (ISCP) Urology Curriculum (Figure 1) and The Joint Surgical Colleges Fellowship Examinations (JSCFT) syllabus, common topics include urinary tract infections (UTIs), inguinoscrotal conditions, phimosis, undescended testes, duplex systems, reflux, hydronephrosis, posterior urethral valves (PUV), spina bifida, intersex, and enuresis.
Embryology and commoncongenital abnormalities [1]
During normal foetal development, the mesonephric duct gives rise to the ureteric bud at the beginning of the fifth week of gestation. The ureteric bud, which gives rise to the ureter, calyces and collecting ducts, advances towards the caudal region of the intermediate mesoderm – the metanephros, fusing at around 32 days and commencing the process of nephrogenesis. Further details can be seen in Table 1.
Common topics / conditions
Recurrent UTI
VUR plays a central role linking UTI, pyelonephritis, renal scarring and end-stage renal disease (ESRD). The RIVUR Trial (2014) reported that prophylactic trimethoprim reduced the risk of recurrent UTIs, but did not reduce occurrence of renal scarring, and increased E.coli resistance patterns [2]. The recommended imaging schedule for babies and children with UTI is illustrated in the 2022 NICE guideline and can be accessed at https://www.nice.org.uk/guidance/ng224. Finally, meta-analysis shows that circumcision reduces the risk of UTI in boys with a history of recurrent UTI or VUR [3].
Urinary incontinence
Urinary incontinence is common in children with diurnal enuresis affecting approximately 15% of four-year-olds, diminishing to 2% in nine-year-olds. A focused history is key to excluding a neurological or anatomical cause (e.g., ureteric ectopia in girls). There is almost never an underlying organic cause for urinary incontinence which occurs solely at night with no daytime symptoms (monosymptomatic nocturnal enuresis). Examination should focus on the abdomen (a palpable bladder which can be ‘expressed’ with suprapubic pressure is pathognomic of neurological disease; while palpable stool will point to constipation), the genitalia, and the spine. Investigations include frequency-volume chart and urinary tract ultrasound and should be performed in all children with diurnal enuresis. Their post-void bladder volume should not be greater than the 10% normal age-adjusted bladder capacity (years + one multiplied by 30). Management of enuresis includes urotherapy (an umbrella term for all non-surgical, non-pharmacological interventions for lower urinary tract disorders (LUTD) in children and adolescents). ERIC, the national charity for children’s bowel and bladder health, is an excellent resource.
Phimosis
The natural history of the foreskin is key in the management timing of phimosis. Oster et al. reported that preputial adhesions were present in up to 63% of six to seven-year-olds, diminishing to 3% in 16–17-year-olds [4]. Prior to that, Douglas Gairdner published the landmark paper ‘The Fate of the Foreskin’ which illustrated that during the first few years of life when the prepuce is still developing, non-retractability is normal and not due to a pathological constriction [5]. A good resource for patient, parents and professionals is: https://4skin-health.alderhey.nhs.uk/
Hydroceles
A patent processus vaginalis (PPV) has been estimated to be present in 80–95% of all male newborns, declining to 60% at one year of age, 40% at two years, and 15– 37% thereafter. Therefore, congenital hydrocoeles should be managed conservatively (except for those with an associated hernia) during the first two years of life. If it persists beyond two years, a PPV ligation (always inguinal approach!) can be offered.
Testicular torsion
As per Mellick and colleagues (2019), salvage rates are highest when presentation and treatment is within zero and six hours (96%), however a proportion (10%) remain viable after >48 hours of symptoms, depending on the degree of torsion [6]. When I attended Torsion Wetlab, run by The South Thames Paediatric Network, a healthy debate revealed that paediatric urology surgeons have a very low threshold for exploration if torsion cannot be excluded, even beyond 48 hours, which is likely informed by the results of the above systematic review.
Cryptorchidism / non-palpable testicles
The undescended testis is a popular topic for the exam. Candidates may be quizzed on the embryologic timeline, the role of imaging (remember there is no role for ultrasound!), surgical treatment (palpable versus non-palpable), and timing of treatment with respect to the risk of testicular cancer [7] versus the risk of testicular atrophy, anaesthetic complications, and infection rate in early orchidopexy i.e., < one year of age [8]. Currently, the recommended age for orchidopexy is between six and twelve months of age.
Non-palpable testes should raise suspicion for congenital adrenal hyperplasia (CAH). CAH is the commonest form of 46XX DSD, and the most common form of ambiguous genitalia in the western world. Severe forms of CAH may present as a paediatric urology emergency due to severe hyponatraemia in neonates.
Hypospadias
The aim of surgical management of hypospadias is to achieve a penis straight enough for erections and intercourse. Understanding the over-riding concepts, rather than listing the various techniques is key. This comprises correction of any chordee, reconstruction of the urethra (i.e., a tubularised urethroplasty with or without incision depending on the width of the urethral plate), and sufficient skin coverage to achieve a good cosmetic result. The best way of understanding these concepts is to scrub in and assist. This will translate to a more fluent and authentic discussion in the exam. Notably, examiners have been known to quiz candidates on the type of dressing used! In general, surgical correction is recommended between six and eighteen months of age.
Hydronephrosis
The incidence of foetal hydronephrosis ranges from 0.5–5%, and when mild, usually represents a transient physiological state. Nevertheless, a significant minority (approximately 0.2%) will be associated with a clinically significant uropathy. The urinary tract dilatation (UTD) classification was developed to grade severity and guide investigations. Upper tract dilatation in the foetus / infant may lead to further discussion of the various underlying aetiologies (e.g., PUJO, VUR, PUV, and urethrocele). These topics may be presented to a candidate using an image (e.g., ‘key-hole sign’ in PUV).
Conclusion
Paediatric urology exam preparation is unpredictable; attending clinics, elective lists, and viva courses like that run by the British Association of Paediatric Urologists (BAPU) is invaluable. I would recommend key resources including the book Essentials of Paediatric Urology (published by CRC Press), PedsUroFLO lectures by the University of California San Francisco (https://pedsuroflo.ucsf.edu/home), and the Course in Operative Paediatric Urology (COPU) run by the paediatric urological surgeons at Leeds General Infirmary. Good luck!
TAKE HOME MESSAGES
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Don’t overlook paediatric urology for the exam.
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Use the curriculum as set out by ISCP and JSCFT to guide your revision.
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Focus on the clinical application of embryology.
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Know the ‘basics’ well.
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Attend paediatric urology clinics and lists.
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Familiarise yourself with the dates of key courses early so as not to miss out.
References
1. Wilcox DT, Thomas DF. Essentials of Paediatric Urology, 3rd edition. Boca Raton, Florida, USA; CRC Press; 2022.
2. The RIVUR Trial Investigators. Antimicrobial prophylaxis for children with vesicoureteral reflux. New England Journal of Medicine 2014;370:2367–76.
3. Singh-Grewal D, Macdessi J, Craig J. Circumcision for the prevention of urinary tract infection in boys: A systematic review of randomised trials and observational studies. Archives of Disease in Childhood 2005;90:853–958.
4. Oster J. Further fate of the foreskin. incidence of preputial adhesions, phimosis, and smegma among Danish schoolboys. Archives of Disease in Childhood 1968;43:200–3.
5. Gairdner D. Fate of the foreskin. British Medical Journal 1949;2:1433–7.
6. Mellick LB, Sinex JE, Gibson RW, Mears K. A systematic review of testicle survival time after a torsion event. Pediatric Emergency Care 2019;35:821–5.
7. Pettersson A, Richiardi L, Nordenskjold A, et al. Kaijser M, Akre O. Age at surgery for undescended testis and risk of testicular cancer. New England Journal of Medicine 2007;356:1835–41.
8. Paediatric Surgical Trainee Research Network. Timing of Orchidopexy and its relationship to postoperative testicular atrophy: Results from the orchestra study. BJS Open 2021;5.
Declaration of competing interests: None declared.
