Paediatric 'mini' examination

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1. Regarding inguinal hernias in children

(a) Boys are affected more often than girls [9l1]

F (b) f Are less common in preterm infants [common]

(c) In infants (less than one years old) approximately 50% present with
incarceration

F (d) f 50% of hernias are bilateral [10.l.]

(e) Approximately 20% of patients will develop a contralateral hernia

Inguinal hernias are the commonest surgical condition of childhood. Approximately 2% of

male infants will develop an inguinal hernia and 99% will be indirect. The male : female ratio
is 9:1. Inguinal hernias are more common on the right and 10% are bilateral. Prematurity is a
significant risk factor. The risk of incareration is increased in infants and therefore a hernia
presenting before one year of age requires urgent surgical assessment. Approximately 20%
will develop a contralateral hernia. The role of contralateral groin exploration at the time of a
unilateral herniotomy is controversial.

2. Regarding undescended testes

(a) 75% of undescended testes descend in the first year of life

F (b) Is associated with a reduced risk of testicular malignancy [increase 5.l.]

(c) Is associated with an increased risk of infertility[ 5"/.] [only 30.l.of bilateral
undesendig testes will be fertil]

F (d) Surgery should be considered in the neonatal period[2 nd year]

(e) Laparoscopy is indicated for impalpable testes [ palpaple undergo

orchidopexy]
/Undescended testes affect 3% of full-term boys. However, the majority of these lie in the
inguinal canal and approximately 75% of undescended testes d with an increased risk of
testicular malignancy which develops in 5% of intra-abdominal testes. Overall, 80% of males
with bilateral descended testes are fertile but only 30% of men with bilateral undescended
testes have normal fertility. Surgery should be performed during the second year of life. Boys
with a palpable testis should undergo a routine orchidopexy. Impalpable testes should be
assessed with laparoscopy.

3. Regarding testicular torsion

(a) The highest incidence is in the neonatal and peripubertal periods

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 (b) May present with abdominal pain and vomiting and few testicular
symptoms

F (c) Radiological investigation with Doppler ultrasound or isotope scanning is

invariably indicated [not Dx and delay surgry]

(d) Testicular viability is reduced if surgery is delayed more than 6 hours

(e) Contralateral orchidopexy should also be performed if a torsion is

confirmed

The commonest causes of the 'acute scrotum' in childhood are testicular torsion, torsion of
an appendix testis and idiopathic scrotal oedema. Testicular torsion can occur at any age but
is most common in the neonatal and peripubertal periods. It usually presents with severe
testicular pain but this may be absent and the testis should be examined in all boys with
abdominal symptoms. If a torsion is clinically suspected then radiological investigations have
little to offer. None are diagnostic and may delay surgery. Testicular viability is reduced with
increasing time from the onset of symptoms. Following reduction of a torsion 3-point fixation
with an non-absorbable suture should be performed. The contralateral testis should also be
fixed.

4. Regarding exomphalos and gastroschisis

F (a) A gastroschisis has a sac[exom...

F (b) Gastroschisis is associated with major congenital abnormalities [exom..

F (c) The postoperative mortality of surgery for gastroschisis approaches 50%

(d) Both conditions may be diagnosed prenatally with ultrasound

F (e) Both conditions require delivery by caesarean section

Exomphalos and gastroschisis are two different congenital anomalies with different clinical
appearances. They are usually diagnosed prenatally by ultrasound but do not inevitably
require delivery by caesarean section. An exomphalos (ompalocele) has a sac, which may
rupture, with umbilicus arising from the apex of the sac. The sac contains intestinal loops,
liver and spleen. It is associated with major congenital anomalies and the prognosis depends
on these associated lesions. A gastroschisi never has a sac and the umbilical cord arises from
the normal site on the abdominal wall. It is rarely associated with other congenital anomalies
and the prognosis is better than for exomphalos.

5. Congenital diaphragmatic hernia

(a) Usually occur through the foramen of Bochdalek[ 90./.]

F (b) Are more common on the right than the left [90./. left]

F (c) Are rarely associated with other congenital anomalies [common 40./.]

(d) Present with respiratory distress in the neonatal period

(e) Neonates usually require sedation, ventilation and intestinal

decompression prior to surgery [36-72 hrs]

Congenital diaphragmatic hernia occurs in approximately 1 in 4,000 live births. 90% occur in
the posterior portion of the diaphragm through the foramen of Bochdalek and 90% occur on
the left. The commonest clinical presentation is with respiratory distress in the neonatal period
and due pulmonary hypoplasia and compression. The abdomen often has a scaphoid
appearance. About 40% of patients have associated congenital anomalies. The diagnosis can
be confirmed radiologically with bowel loops seen in the chest. Neonates usually require

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sedation, ventilation and intestinal decompression prior to surgery between 36 and 72 hours
after birth

6. Regarding oesophageal atresia and tracheo-oesophageal fistula (TOF)

F (a) Most cases of oesophageal atresia are associated with a proximal TOF
to the lower oesophagus [distal. tof 90./. to upp.oesophag]

F (b) Often present prenatally with oligohydramnios [poly]

(c) Postnatally present with difficulty swallowing and aspiration

d t The diagnosis my be confirmed by the inability to pass a nasogastric catheter
[>10cm]or [ water contrast meal]

(e) Radiological evidence of gas in the stomach confirms the presence of

distal TOF

Oesophageal atresia is often associated with tracheo-oesophageal fistula (TOF).

Approximately 90% of patients have a distal TOF between the upper oesophagus and
trachea. Polyhydramnios may be present prenatally. Postnatally the diagnosis my be
confirmed by the inability to pass a nasogastric tube more than 10 cm. If doubt continues the
diagnosis can be confirmed by passing a small volume of water-soluble contrast down the
tube. Radiological evidence of gas in the stomach confirms a distal TOF. Primary repair of the
atresia is possible in a significant proportion of neonates

7. Regarding meconium ileus

F (a) Is a rare cause of neonatal intestinal obstruction [common]

F (b) Less than 5% of cases are associated with cystic fibrosis [80./.]

(d) Presents with neonatal bile-stained vomiting and abdominal distension

(e) A plain x-ray may show an intra-luminal 'ground glass' appearance and
dilated bowel

Meconium ileus is a common cause of neonatal intraluminal intestinal obstruction. Over 80%
of cases are associated with cystic fibrosis. In these patients, pancreatic secretions are
abnormally viscid and the meconium becomes inspisated in the distal ileum. Beyond the level
of the obstruction the bowel is collapsed and the colon is empty. Bile-stained vomiting in a
neonate is always abnormal and is a feature of meconium ileus. A plain abdominal x-ray will
show dilated ileal loops and intraluminal 'ground glass' appearance. Surgical treatment can be
by enterotomy and lavage
8. Regarding infantile hypertrophic pyloric stenosis

F (a) Usually presents between 6 and 12 months of age [6wks]

F (b) The female : male ratio is 4:1 [m:f 4:1]

(c) Has a strong familial predisposition [5./. mother]

F (d) Pathologically shows hypertrophy of the longitudinal muscle layer of the

pylorus [circular muscle]

F (e) Presents with bile-stained projectile vomiting [non bilous]

Infantile hypertrophic pyloric stenosis present most commonly at approximately 6 weeks

of age. It is more common in boys with a male : female ratio of 4:1. There is a strong familial
predisposition with 5% of affected infants having a mother who also developed the problem.
Pathologically, the pyloric 'tumour' arises from hypertrophy the circular muscle layer. Patients
present with projectile vomiting that is not bile-stained. Following resuscitation and correction
of any electrolyte abnormality, surgical treatment is by pyloromyotomy.

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9. Regarding intussusception

(a) It is the commonest cause of intestinal obstruction between 6 and 18

months

F (b) Usually occurs in the jejunum [iliocolic]

(c) The lead point may be a Peyer's patch or Meckel's diverticulum

F (d) Usually presents with few clinical signs

(e) Has a characteristic 'doughnut' appearance on ultrasound

Intussusception is the commonest cause of intestinal obstruction in the 6 to 18 month age
group. It often occurs in the distal ileum with an ileo-colic intussusception being the most
common type. Lead points include an inflamed Peyer's patch or a Meckel's diverticulum. The
infants usually present with severe intermittent colic, bile-stained vomiting, rectal bleeding and
30% have a 'sausage-shaped' abdominal mass. The diagnosis can often be confirmed by a
'doughnut' appearance on ultrasound.

10. Regarding Hirschsprung's disease

(a) Often presents with neonatal large bowel obstruction [mainly distal may be
proximal .whole colon in5.l.]

(b) Results from absence of ganglion cells in both the Meissner's and
Auberbach's plexus

F (c) A contrast-study will show dilatation of the aganglionic segment

[narrowing] [saw tooth appearance]

F (d) The diagnosis can be confirmed by histological evidence of reducined

acetylcholinesterase in the aganglionic segment [increase]

(e) Early treatment may involve rectal irrigation or an emergency colostomy

Hirschsprung's disease is a common cause of neonatal large bowel obstruction. It results from failure of
migration of ganglion cells to the affected segment of bowel. This always involves the distal colon but
the proximal extent of the involvement is variable and in rare cases may involve the whole of the large
bowel 5./.. Histologically, the affected segment has absent ganglion cells in the Meissner's and
Auerbach's plexus but immunohistochemical evidence of increased ACE activity. 80% of cases present
in the neonatal period. Contrast studies show the affected segment to be tonically contracted. Rectal
irrigation or an emergency colostomy may be required before a definitive 'pull-through' procedure.