2008 Paper B Flashcards Preview

Paeds Exam > 2008 Paper B > Flashcards

Flashcards in 2008 Paper B Deck (100):

A five-year-old boy presents with a two day history of swelling of the parotid gland, with associated pain and low-grade fever. He had a similar episode eight months previously. He has obvious swelling of the left cheek, obscuring the angle of the jaw. It is moderately tender. No discharge can be manually expressed from the parotid duct.
The most likely diagnosis is:
A. acute suppurative parotitis.
B. idiopathic recurrent parotitis.
C. mumps.
D. sialolithiasis.
E. Sjögren syndrome

B. idiopathic recurrent parotitis.


A full-term 4.6 kg male infant has recurrent dusky episodes commencing eight hours after a difficult vaginal delivery complicated by mild shoulder dystocia following prolonged rupture of membranes. APGAR scores were six at one minute and nine at five minutes and he was given brief bag and mask ventilation to improve his colour. He is sleepy and has not fed well for the past five hours.
On examination, he has a suffused face, no respiratory distress or heart murmurs and a normotensive fontanelle. His blood glucose level is 4.0 mmol/L and as part of a septic work-up he has a lumbar puncture which gave the following cerebrospinal fluid (CSF) results:

The most likely cause for these findings is:
A. herpes simplex encephalitis.
B. meningitis.
C. subarachnoid haemorrhage.
D. subdural haematoma.
E. traumatic lumbar puncture


C. subarachnoid haemorrhage


A nine-year-old boy is referred for problems with sleeping. He goes to bed at 9 p.m., but is frequently awake for two or more hours before finally falling asleep. During this time he is frequently calling out to his parents, complaining of hearing noises, seeing things in his room and not wishing to be alone. He describes being worried someone is going to break into his house during the night.
Once asleep, he sleeps through the night. He gets up reluctantly at 7 a.m. on weekdays and spontaneously at 7.30 a.m. on weekends. He is not noticeably sleepy during the day, but sometimes falls asleep in the car. During the day he is a confident boy, with many friends and no difficulties separating from his parents for school or other activities.
The most likely primary diagnosis is:
A. generalised anxiety disorder.
B. insomnia with bedtime fears.
C. narcolepsy.
D. night terrors.
E. sleep phase delay syndrome.

B.  insomnia with bedtime fears


What is the commonest cause of failure to thrive in infancy in developed countries?

A. Chronic organ failure.
B. Gastrooesophageal reflux.
C. Inadequate intake.
D. Malabsorption.

E.Recurrent infection

C. Inadequate intake


A 14-year-old girl with a seizure disorder presents because of ongoing seizures. She was initially diagnosed with "grand mal" epilepsy following her first tonic-clonic seizure at 12 years of age.
Her teachers have expressed concern about brief periods of "tuning out" in the classroom. Her parents tell you that she is clumsy and seems "jumpy" first thing in the morning.
Her electroencephalogram (EEG) shows generalised spike waves.
Which of the following anticonvulsants is most likely to worsen her seizures?
A. Carbamazepine.
B. Clonazepam.
C. Phenobarbitone.
D. Sodium valproate.
E. T opiramate.

A. Carbamazepine


A six-month-old female infant presents with a one week history of cough and shortness of breath. She was born at 37 weeks gestation by Caesarean section for breech presentation. There were no problems in the neonatal period. She has been gaining weight well and developing normally. On examination, she is afebrile, with a respiratory rate of 50/min and intercostal recessions. On auscultation, breath sounds are reduced on the right side posteriorly. She has a right Horner syndrome. Her chest X-ray is shown below

Which of the following is the most likely diagnosis?
A. Congenital bronchogenic cyst.
B. Cyst adenomatoid malformation.
C. Neuroblastoma.
D. T eratoma.
E. Thymoma.

C. Neuroblastoma


A five-year-old boy is diagnosed with Duchenne muscular dystrophy. At the time of diagnosis he has a normal cardiac examination, electrocardiogram (ECG), echocardiogram and 24-hour Holter monitor. The cardiac complication most likely to develop in this child is:
A. dilated cardiomyopathy.
B. hypertrophic cardiomyopathy.
C. mitral valve prolapse.
D. supraventricular arrhythmias.
E. ventricular arrhythmias.

A. dilated cardiomyopathy


A previously well six-year-old boy presents with fever and headache. A computed tomography (CT) scan of his brain is shown below.

Which of the following is the most appropriate empiric antibiotic regimen?
A. Ampicillin plus Gentamicin.
B. Cefotaxime plus Gentamicin.
C. Cefotaxime plus Metronidazole.
D. Metronidazole plus Gentamicin.
E. Vancomycin plus Gentamicin.

C. Cefotaxime plus Metronidazole


A fully breast fed female infant born at 41-weeks’ gestation with a birth weight of 3.60 kg is noted to have significant persistent jaundice at two weeks of age. She is still below her birth weight. On physical examination, she is found to have an umbilical hernia, decreased tone and a large anterior fontanelle (4 x 6 cm). The most likely diagnosis is:
A. biliary atresia.
B. breast milk jaundice.
C. Crigler–Najjar syndrome.
D. galactosaemia.
E. hypothyroidism

E. hypothyroidism


A seven-year-old girl is referred for investigation of pallor, lethargy and bruising. Her oral appearance is shown below

Which of the following is the most likely diagnosis?
A. Acute lymphoblastic leukaemia (ALL).
B. Acute myeloid leukaemia (AML).
C. Aplastic anaemia.
D. Burkitt lymphoma.
E. Neuroblastoma.

B. Acute myeloid leukaemia (AML)


A term male neonate presents on day three of life with a history of 12 hours of increasing sleepiness and poor feeding. On examination he has truncal hypotonia but has hypertonic limbs. He does not cry when blood is taken. On initial investigation he is normoglycaemic. His arterial blood gases are as follows:

He is most likely to have a disorder of which of the following groups?
A. Congenital disorders of glycosylation.
B. Mitochondrial disorders.
C. Organic acidaemias.
D. Peroxisomal disorders.
E. Urea cycle disorders

E. Urea cycle disorders


A 14-year-old boy who was admitted to a peripheral hospital three days ago with a history of fevers and macroscopic haematuria is referred for renal assessment. He had previously been well, aside from being treated with oral flucloxacillin for cellulitis following excision of a benign naevus one month ago. His investigations are shown below.

The most likely diagnosis is:
A. acute post-streptococcal glomerulonephritis.
B. Alport syndrome.
C. haemolytic uraemic syndrome.
D. IgA nephropathy.
E. systemic lupus erythematosus (SLE).

E. systemic lupus erythematosus (SLE)


A four-year-old boy was playing with his brother and accidentally swallowed a coin. Initially there was some coughing and spluttering but he subsequently settled. An X-ray taken at the Emergency Department four hours later shows the coin to be at the lower oesophagus just above the gastrooesophageal junction. What is the most appropriate next step?
A. Barium swallow.
B. Domperidone.
C. Endoscopic removal.
D. Oral fluid bolus.
E. X-ray in 48 hours.

C. Endoscopic removal


A four-year-old child has a history of recurrent oral thrush and fungal nail infections since infancy which recur whenever oral anti-fungal medications cease. A clinical photograph of his nails is shown below.

Which of the following disorders is the child most at risk of developing?
A. Autoimmune hepatitis.
B. Coeliac disease.
C. Diabetes mellitus.
D. Hypothyroidism.
E. Thymoma.

D. Hypothyroidism


A term neonate presents with severe cyanosis from the time of delivery. The diagnosis of obstructed total anomalous pulmonary venous drainage is confirmed by echocardiograph. The intervention which would be most likely to adversely affect the patient’s clinical state would be:
A. dobutamine.
B. dopamine.
C. frusemide.
D. oxygen.
E. prostaglandin E1

E. prostaglandin E1


A six-month-old male infant presents with a swelling on the left side of his face as shown in the photograph below

At birth, facial asymmetry and mild fullness of the left cheek had been noted. By three months of age a soft, compressible non-tender mass was noted and seemed to be growing slowly over time. There was no discolouration of overlying skin.
Three days before this presentation he developed fever and irritability and the mass suddenly doubled o
in size. On examination he had a temperature of 38.5 C. The mass was hard, tender, erythematous and warm. There was impetigo on the face and cracking below the left pinna. There was no bruit on auscultation.

His admission laboratory results included:

Haemoglobin (Hb) 104 g/L [100 – 130 g/L] 

Platelets 491 x 10 /L [150 – 450 x 10 /L] 

White Cell Count (WCC) 18.6 x 10 /L [4.0 – 15.0 x 10 /L] 

Neutrophils 11.0 x 10 /L  [0.5 –7.0 x 10 L] 
C–reactive Protein 29 mg/L[<5 mg/L]

The most likely diagnosis is:
A. branchial cyst.
B. haemangioma.
C. lymphatic malformation.
D. parotitis.
E. thyroglossal cyst.

C. lymphatic malformation


A 14-year-old girl presents to the Emergency Department following a paracetamol overdose. Which of the following features on history is most predictive of a further suicide attempt?
A. Current antidepressant therapy.
B. Family history of completed suicide.
C. Past diagnosis of depression.
D. Past suicide attempts.
E. Presence of anxiety disorder.

D. Past suicide attempts


A four-week-old girl is brought into the Emergency Department with increasing redness and swelling of both breasts. A clinical photograph is shown below

Which of the following is the most likely causative organism?
A. Group A beta-haemolytic Streptococcus.
B. Group B Streptococcus.
C. Listeria monocytogenes.
D. Pseudomonas aeruginosa.
E. Staphylococcus aureus.

E. Staphylococcus aureus


A two-year-old child became unwell with fever and irritability. After two days, he developed a rash. The fever settled over the next day, and the rash evolved as shown in the photograph below.

Which of the following most commonly causes secondary skin infection in this condition?
A. Haemophilus influenzae.
B. Pseudomonas aeruginosa.
C. Staphylococcus epidermidis.
D. Streptococcus pneumoniae.
E. Streptococcus pyogenes.

E. Streptococcus pyogenes


An eight-week-old ex-premature baby with congenital hypothyroidism fails to respond to an adequate dose of thyroxine given regularly. The baby is breast fed and is on nutritional supplements. Which of the following nutritional supplements is most likely to affect absorption of thyroxine?
A. Folic acid.
B. Iron.
C. Phosphate.
D. Vitamin A.
E. Vitamin D

B. Iron


A four-week-old infant is referred for assessment as she has not yet regained her birth weight. Her mother reports that breast feeding is not well established. The infant is not clinically cyanosed, but is mildly tachypnoeic with mild hepatomegaly. Pulses are normal. Heart sounds are normal. There is a grade 3/6 systolic murmur. The electrocardiogram (ECG) is shown below


This clinical scenario would be most consistent with the diagnosis of:
A. atrioventricular septal defect.
B. patent ductus arteriosus.
C. tetralogy of Fallot.
D. truncus arteriosus.
E. ventricular septal defect

A. atrioventricular septal defect


A 14-year-old has recently been diagnosed with anorexia nervosa. She has a body mass index (BMI) of 15 kg/m2. She was commenced on nasogastric feeds. The level of which of the following electrolytes is most likely to fall if calories are given too rapidly?
A. Calcium.
B. Chloride.
C. Magnesium.
D. Phosphate.
E. Sodium.

D. Phosphate


You are asked to see a term born infant who is now 12 hours old, because of scalp swelling as shown below


A full blood count was performed:

Haemoglobin (Hb) 8.7 g/L [13.0 18.0 g/dL] 

White Cell Count (WCC) 13.0 x 109/L [6.0 – 18.0 x 109/L] 

Platelets 24 x 109/L [150 - 400 x 109/L]

The most likely diagnosis is:

A. Bernard-Soulier syndrome.
B. congenital cytomegalovirus infection.
C. Glanzmann thrombasthenia.
D. idiopathic thrombocytopenic purpura.
E. neonatal alloimmune thrombocytopenic purpura.


E. neonatal alloimmune thrombocytopenic purpura


In the management of phenylketonuria, the mainstay of treatment is the restriction of dietary intake of:
A. carbohydrate.
B. cholesterol.
C. long-chain triglycerides.
D. phytanic acid.
E. protein.

E. protein


An otherwise well ten-year-old girl with a mild intellectual disability presents for assessment. There are no abnormal findings on clinical examination. Her mother has had two miscarriages and a history of early menopause. The maternal grandfather has recently been referred to a neurologist for investigation of ataxia.
Which one of the following is the most likely diagnosis?
A. Fragile X syndrome.
B. Juvenile onset Huntington disease.
C. Maternal phenylketonuria.
D. Triple X syndrome.
E. Unbalanced form of a familial chromosomal translocation.

A. Fragile X syndrome


In children with immunodeficiency, the purpose of routine irradiation of administered blood products is to decrease the risk of:
A. alloimmunisation.
B. cytomegalovirus (CMV) infection.
C. graft-versus-host disease.
D. transfusion related acute lung injury (TRALI).
E. variant Creutzfeld-Jakob disease (vCJD).

C. graft-versus-host disease


A five-year-old boy is brought to the Emergency Department. His parents report that he was well when he woke, but by midday he was so unsteady he could not walk. On examination he looks well but frightened. His fundi are normal and his eye movements full, but he has nystagmus on lateral gaze. He has an unsteady gait and falls frequently, but his strength and reflexes are normal.
What is the most likely diagnosis?

A.Guillain-Barré syndrome.

B. Medulloblastoma.


D. Post-infectious cerebellitis.


D. Post-infectious cerebellitis


A six-month-old male infant was admitted with recurrent cough and feeding difficulties. He had been born at 29 weeks gestation. His chest X-ray showed hyperexpansion and increased interstitial markings. Antibody levels were performed:

The most likely cause of these findings is:
A. intestinal lymphangiectasia.
B. protein malabsorption.
C. severe combined immunodeficiency.
D. transient hypogammaglobulinaemia of infancy.
E. X-linked hypogammaglobulinaemia.

D. transient hypogammaglobulinaemia of infancy


A seven-year-old boy is seen with the development of pubic hair over the last 12 months. His growth
velocity is reported to have increased over the same time period. He has previously been well. On th
examination he is over the 97 percentile for height, he has Tanner stage 3 genital development and Tanner stage 3 pubic hair. His testes are 2 ml bilaterally. Initial investigations are as follows:

The most likely cause of his increased growth velocity and pubic hair development is which of the following?
A. Adrenocortical tumour.
B. Benign premature adrenarche.
C. Central precocious puberty.
D. Congenital adrenal hyperplasia.
E. Craniopharyngioma.

D. Congenital adrenal hyperplasia


A five-year-old girl presents with a one week history of pain behind the left ear. On examination she is afebrile. There is a warm, fluctuant mass with erythema of the overlying skin. The left tympanic membrane is bulging and red.
The appearance of the mass is shown in the photograph below

The most likely diagnosis in this case is:
A. acute mastoiditis.
B. atypical mycobacterium infection.
C. infected cystic hygroma.
D. infected sebaceous cyst.
E. postauricular lymphadenitis.

A. acute mastoiditis


Parents of children with autism are often confused about the best interventions to help their child. Which therapy has the best evidence for improving communication outcomes in autism?
A. Atypical antipsychotics.
B. Cerebellar-based therapy.
C. Early intensive behavioural intervention.
D. Secretin.
E. Signing

C. Early intensive behavioural intervention


A ten-year-old girl presents with a three month history of chronic dry cough day and night without wheezing. It is aggravated by exercise and cold air. Baseline chest X-ray and lung function are normal.
What is the most likely diagnosis?

A. Cough variant asthma.

B. Non specific cough.

C. Primary ciliary dyskinesia.

D. Psychogenic cough.

E. Tracheomalacia.

B. Non specific cough


An eight-and-a-half-year-old boy is referred for review of his multiple birth marks as demonstrated in the clinical photograph below. He is well, has no family history of note and has normal growth and development. Physical examination is normal apart from mild pectus excavatum and a soft ejection systolic murmur.

The test or procedure most likely to assist in confirming his suspected diagnosis is:
A. computed tomography (CT) scan of his head.
B. echocardiogram.
C. fundoscopy.
D. skeletal survey.
E. slit lamp examination.

E. slit lamp examination


The electrocardiogram (ECG) shown below is performed on a six-year-old boy because he is noted to have an irregular pulse on routine examination. There is no history of cardiac symptoms.

He is at risk of developing:
A. atrial ectopic tachycardia.
B. atrial fibrillation.
C. complete heart block.
D. re-entrant supraventricular tachycardia.
E. second degree heart block.

D. re-entrant supraventricular tachycardia


A three-year-old boy was found by his mother playing with a syringe in a playground. She brings him to the local Emergency Department with the syringe. He has a small puncture wound on the left palm. He has only had two doses of hepatitis B containing vaccine. The syringe has some dried blood in the hub.
Which of the following should be given?
A. Hepatitis B immunoglobulin.
B. Hepatitis B vaccine.
C. Interferon.
D. Normal immunoglobulin.
E. Zidovudine.

B. Hepatitis B vaccine


An 11-year-old girl presents with a three day history of a painful and swollen right ear. On examination she has asymmetrical facial movements and a swollen and erythematous right pinna, as demonstrated in the clinical photographs below

Which of the following is the most likely explanation for her presentation?
A. Auricular cellulitis.
B. Cholesteatoma.
C. Mastoiditis.
D. Otitis externa.
E. Ramsay-Hunt syndrome.

E. Ramsay-Hunt syndrome


A male infant born at 27 weeks gestation, who is now seven days old, has temperature instability and a paucity of activity, in the absence of evidence of sepsis. His thyroid function is checked and the results are as follows:

The most likely diagnosis explaining these biochemical findings is:
A. hypoxic-ischaemic insult.
B. maternal iodine deficiency.
C. primary hypothyroidism.
D. secondary hypothyroidism.
E. transient hypothyroxinaemia

E. transient hypothyroxinaemia


You review a 15-month-old girl whose father has a diagnosis of neurofibromatosis type 1 (NF1). Her parents want to know if she is affected. If she is affected, which feature is most likely to be present?
A. Axillary freckling.
B. Lisch nodules.
C. Multiple café au lait macules.
D. Optic glioma.
E. Plexiform neurofibroma.

C. Multiple café au lait macules


Antipsychotic medications such as risperidone and haloperidol are used by paediatricians to treat Tourette syndrome, and the symptoms of aggression and anxiety in autism. An acute side effect of these medications is painful and distressing muscle spasms. These can be reversed by which of the following?
A. Benztropine.
B. Cyproheptadine.
C. Diazepam.
D. Flumazenil.
E. Naloxone.

A. Benztropine


A nine-year-old boy is referred with a six month history of involuntary jerking movements. Initially this involved facial twitches, then he had a period of blinking, and more recently he has been turning his head to the left with some elevation of the left shoulder. These have been observed mostly at home. His mother spoke to his teacher, who said she has not noticed any unusual movements. He is popular at school. His concentration is poor. His academic progress has been satisfactory to date. Systems review reveals a persistent dry cough.
What pharmacological treatment is indicated?
A. Clonidine.
B. Haloperidol.
C. Methylphenidate.
D. None.
E. Risperidone.

D. None


An obese six-year-old girl presents with a four week history of limp with pain in the right hip and medial thigh. On examination she has a low-grade fever, rhinorrhoea and limited internal rotation of the right hip. An X-ray of her pelvis is shown below.

The most likely diagnosis is:
A. irritable hip.
B. juvenile chronic arthritis.
C. osteomyelitis.
D. Perthes disease.
E. slipped upper femoral epiphysis.

D. Perthes disease


In children with recently diagnosed lymphoma, which one of the following therapies is ineffective in reducing the risk of acute kidney injury as a result of tumour lysis syndrome?
A. Allopurinol.
B. Frusemide.
C. Normal (0.9%) saline.
D. Sodium bicarbonate.
E. Uric oxidase (Rasburicase ).

B. Frusemide


Amniocentesis is performed for fetal chromosomal analysis because of advanced maternal age. The study reveals a karyotype of 46XY. High resolution ultrasound performed later in the pregnancy (18 weeks) demonstrates normal female external genitalia. The most likely explanation for this clinical scenario is which of the following?
A. 21-hydroxylase deficiency.
B. Androgen insensitivity.
C. Growth hormone deficiency.
D. Hypogonadotrophic hypogonadism.
E. Maternal contamination of the chromosomal sample

B. Androgen insensitivity


A three-year-old child presents with tachycardia of 210 beats/minute. He is afebrile and clinically stable. While being examined he reverts to sinus rhythm without treatment or intervention. The change to sinus rhythm of 114 beats/minute is captured on the rhythm strip shown.

The findings are consistent with a diagnosis of:
A. atrial ectopic tachycardia.
B. junctional tachycardia.
C. sinus tachycardia.
D. ventricular tachycardia.
E. Wolff-Parkinson-White (WPW) syndrome

A. atrial ectopic tachycardia


A 16-year-old female was diagnosed with ulcerative colitis at the age of 12. Her disease was fairly well controlled, initially with steroids and subsequently on maintenance salazopyrine. Over the last six months she complained of poor concentration, tiredness and vague upper abdominal pain. Blood investigation done by her general practitioner showed:

What condition does this patient most likely have?
A. Autoimmune hepatitis.
B. Cholelithiasis.
C. Non-alcoholic steatohepatitis (NASH).
D. Sclerosing cholangitis.
E. Viral hepatitis.

D. Sclerosing cholangitis


A 15-year-old girl with known anorexia nervosa is brought to the Emergency Department following a collapse at school. On examination she is alert and orientated but feels faint when standing. She is clinically dehydrated with dry mucous membranes, reduced tissue turgor and reduced urine output.

Her heart rate is 45, respiratory rate 30, temperature 35.5 C and blood pressure 90/65 mmHg. Her
blood chemistry is shown below.


Which of the following would be the most likely abnormality to be demonstrated on a 12 lead electrocardiogram?
A. Elevation ST segment.
B. Peaked T-waves.
C. Reduced PR interval.
D. Shortened QT interval.
E. U-waves

E. U-waves


A 12-year-old boy is referred for investigation of a first episode of acute psychosis. He has a past history of mild developmental delay, with recent psychometric testing indicating that he is functioning in the borderline range of intellectual handicap. He had a small ventricular septal defect identified in infancy, for which surgical correction was not required. His facial features are shown in the photograph below.

The most likely diagnosis is:
A. Fragile X syndrome.
B. myotonic dystrophy.
C. Noonan syndrome.
D. velocardiofacial syndrome.
E. Williams syndrome

D. velocardiofacial syndrome


In the staging of Hodgkin lymphoma, several well-recognised constitutional symptoms are known as ‘B symptoms’ and are associated with an increased risk of recurrence. Which one of the following is a ‘B symptom’ in Hodgkin lymphoma?
A. Anorexia.
B. Lethargy.
C. Night sweats.
D. Pain with alcohol ingestion.
E. Pruritis.

C. Night sweats


A 6 month-old girl presents to the Emergency Department with fever and cough. On examination, her o
temperature is 39.5 C, respiratory rate is 60/minute, and oxygen saturation is 95% in room air. She has increased work of breathing, and is noted to have reduced air entry with bronchial breath sounds in the right midzone. A chest X-ray is performed and shown below.

Which of the following is the most appropriate initial therapy?
A. Intravenous azithromycin.
B. Intravenous benzylpenicillin.
C. Intravenous ceftriaxone.
D. Oral amoxycillin.
E. Oral erythromycin.

B. Intravenous benzylpenicillin


Conduct disorder describes a maladaptive and persistent pattern of behaviour encompassing a range of symptoms including aggression, destruction of property, deceitfulness, and serious violations of rules. Early onset (before age 10) conduct disorder most strongly predicts which adult mental health problem?
A. Antisocial personality disorder.
B. Anxiety disorder.
C. Bipolar affective disorder.
D. Major depressive disorder.
E. Schizophrenia.

A. Antisocial personality disorder


A two-year-old girl presents with a three month history of deteriorating gait and behavioural
disturbance. She was born at 33 weeks gestation with an uncomplicated neonatal course. Prior to
presentation there were no concerns on the part of her parents.

On examination she was ataxic, ankle jerks were absent and plantar responses upgoing.
A magnetic resonance imaging (MRI) scan is performed and shown below.

What is the most likely diagnosis?
A. Adrenoleukodystrophy.
B. Ataxia telangiectasia.
C. Friedreich ataxia.
D. Metachromatic leukodystrophy.
E. Periventricular leukomalacia.

D. Metachromatic leukodystrophy

Look for "tigroid" appearance on MRI.

Sparing of subcortical U fibres.


Death during childhood and adolescence in patients with type 1 diabetes is most commonly due to:

A. Addison disease.
B. diabetic ketoacidosis.
C. hypoglycaemia.
D. infection.
E. suicide.

B. diabetic ketoacidosis.


A term born infant is found to be cyanosed at 12 hours of age and subsequent investigation reveals that he has transposition of the great arteries with intact ventricular septum. He is transferred to the nearest cardiac surgical centre and has a balloon atrial septostomy, after which his oxygen saturation in air is 78%. On day three he is commenced on enteral milk feeds. On day five he develops abdominal distension, bilious aspirates and blood in his stool. The following abdominal X-ray is taken:

The most likely diagnosis is:
A. Hirschsprung colitis.
B. malrotation and volvulus.
C. meconium ileus.
D. necrotising enterocolitis.
E. stress ulceration and perforation.

D. necrotising enterocolitis


A two-year-old boy presents with a history of recurrent ear infections with discharge. He is diagnosed
with X-linked agammaglobulinaemia. What laboratory abnormality would be most specific in
confirming this diagnosis?

A. Absent B cells.
B. Absent T cells.
C. Low immunoglobulin G level.
D. Low neutrophil count.
E. Undetectable immunoglobulin A level.

A. Absent B cells.


An 11-year-old boy has type 1 diabetes. He is brought to the Emergency Department at 4 a.m. on
Friday morning following a hypoglycaemic convulsion. On questioning, his parents report that he has
football training on Thursday afternoons before dinner.
His insulin regimen is long acting insulin and a short acting insulin analogue given together at
breakfast and dinner.
Which of the following would be the best advice to avoid recurrent nocturnal hypoglycaemia after
football training?

A. Decrease his activity at football training.

B. Increase the fat content of his dinner after football training.

C. Reduce the long acting insulin dose at breakfast.

D. Reduce the long acting insulin dose at dinner.

E. Reduce the short acting insulin dose at dinner.

D. Reduce the long acting insulin dose at dinner.


A ten-month-old boy of non-consanguineous parents is found to have severe haemophilia A
(factor VIII deficiency). His father also has severe haemophilia A. His mother is found to be a carrier
of haemophilia A. The chance of a male sibling having the disorder is closest to:

A. zero.
B. 25%
C. 50%
D. 75%
E. 100%

C. 50%


A three-year-old is referred with behavioural problems. He gets extremely worked up, throws himself
onto the ground, kicking and screaming, and often bangs his head. On some days this occurs
5-6 times. His mother finds this distressing, and embarrassing when it occurs in public places.
Further history reveals that he is generally hyperactive, has a short attention span and sleeps poorly.
His father was diagnosed with hyperactivity as a child. His developmental screen (using the Ages and
Stages Questionnaire) is negative. Examination is normal.

What management strategy would you recommend?

A. Cognitive behavioural therapy.
B. Ignoring.
C. Logical consequences.
D. Stimulant medication.
E. Time out.

B. Ignoring


A seven-year-old boy is referred with poorly controlled asthma. He has been taking inhaled fluticasone 125 mcg two puffs twice daily for the past six months, but continues to have daily wheeze and cough requiring up to ten puffs of salbutamol/day.
A chest X-ray shows hyperinflation but no other abnormality. Lung function testing shows a moderate obstructive pattern with a 92% increase in forced expiratory volume in one second (FEV1) after bronchodilator. His flow-volume loops are shown below

The next most appropriate step would be to:
A. add 10 mg prednisolone on alternate days.
B. add inhaled salmeterol 50 mcg twice daily.
C. add oral montelukast, 5 mg once daily.
D. double the fluticasone dose to 250 mcg two puffs twice daily.
E. replace the fluticasone with budesonide 100 mcg two puffs twice daily.

B.  add inhaled salmeterol 50 mcg twice daily


An eight-year-old girl who recently commenced overnight automated peritoneal dialysis is brought to the Emergency Department with a six hour history of central abdominal pain. On examination, she is afebrile, with mild generalised abdominal discomfort but no abdominal guarding or rebound tenderness. The Tenckhoff exit site is mildly inflamed with a small amount of purulent exudate. Urgent Gram stain of the peritoneal fluid is shown below.

The most appropriate antibiotic treatment is:
A. intraperitoneal cephazolin.
B. intraperitoneal flucloxacillin.
C. intravenous vancomycin.
D. oral cephalexin.
E. oral flucloxacillin.

A. intraperitoneal cephazolin


Beckwith–Wiedemann syndrome is a well recognised disorder of somatic overgrowth that is associated with cancer predisposition. The most commonly reported tumour is:
A. adrenocortical carcinoma.
B. hepatoblastoma.
C. leiomyosarcoma.
D. neuroblastoma.
E. Wilms tumour.

E. Wilms tumour.


A term born infant presents to the Emergency Department at five days of age with a six hour history of bilious vomiting. The parents report that he passed a normal stool 12 hours beforehand. On examination, he has mild abdominal distension and his perfusion is decreased, with a capillary refill time of three seconds. Plain abdominal X-ray is normal.
Which of the following investigations is most likely to be diagnostic?
A. Abdominal ultrasound.
B. Air enema.
C. Barium enema.
D. Barium meal.
E. Computed tomography scan of the abdomen.

D. Barium meal


An eight-year-old girl is referred for assessment of her chronic perineal irritation. A photograph of her genitalia is shown below

Which of the following is the most likely diagnosis?
A. Child sexual abuse.
B. Lichen sclerosis et atrophicus.
C. Mucocutaneous candidiasis.
D. Perineal psoriasis.
E. Pinworm infestation.

B.  Lichen sclerosis et atrophicus


A ten-year-old boy is referred with long-standing concerns regarding inattentive and impulsive behaviour. These symptoms are present in both home and school settings, and are causing significant impairment in academic and social functioning. He was diagnosed with idiopathic generalised epilepsy at age six. He has good seizure control with sodium valproate. 

What is the most appropriate pharmacological treatment for his inattention and impulsivity?

A. Atomoxetine.
B. Clonidine.
C. Methylphenidate.
D. Risperidone.

E. Sertraline.

C. Methylphenidate


A two-year-old boy was brought to the Emergency Department after he passed a large amount of blood per rectum. He was a previously healthy boy and on clinical examination he appeared pale but alert. He was not in any distress, his heart rate was 160 beats/minute and his systolic blood pressure was 70 mmHg. Examination revealed a soft but mildly distended abdomen. There was no localised tenderness or palpable mass. He continued to pass maroon coloured clots during the examination. Initial haemoglobin was 70 g/L [105 – 135 g/L].
What is the most likely diagnosis?

A. Allergic colitis.
B. Duodenal ulcer.

C. Intussusception.
D. Meckel diverticulum.

E. Rectal polyp.

D. Meckel diverticulum


There is a risk of sudden death associated with sports activities in children with congenital heart disease. Participation in competitive sports would pose the greatest risk to a 12-year-old boy with which of the following lesions?
A. Large atrial septal defect.
B. Moderate aortic stenosis.
C. Post-operative arterial switch for transposition of great vessels with normal haemodynamics.
D. Post-operative repair of tetralogy of Fallot with normal haemodynamics.
E. Restrictive ventricular septal defect.

B. Moderate aortic stenosis


You are asked to see a four-month-old in the Intensive Care Unit. He has been hypotonic and weak since birth. On examination, there is no facial weakness but he has profound weakness of the extremities with areflexia. His chest X-ray is shown.

The most likely diagnosis is:
A. congenital myotonic dystrophy.
B. mitochondrial myopathy.
C. nemaline myopathy.
D. Pompe disease.
E. spinal muscular atrophy.

D. Pompe disease


An 18-month-old boy presents with a seven day history of fever, irritability, and refusal to walk. On o
examination his temperature is 38.9 C. He has erythematous and oedematous hands and feet. He has pharyngitis. He has unilateral cervical lymphadenopathy.
Which of the following results is least consistent with the diagnosis of Kawasaki disease?
A. Cerebrospinal fluid lymphocytosis.
B. Elevated serum transaminases.
C. Sterile pyuria.
D. Thrombocytopenia.
E. T oxic granulation in neutrophils.

D. Thrombocytopenia


A 15-year-old boy presents to the Emergency Department following a fall onto both hands during a basketball match. He complains of pain and tenderness at the base of his right thumb and wrist. There is no obvious deformity or swelling and his radiograph is provided below.

Which of the following is the next best step in management?
A. Compression bandage.
B. Removable wrist splint.
C. Short arm backslab.
D. Short arm full plaster.
E. Short arm plaster with thumb spica.

E. Short arm plaster with thumb spica


In mild diffuse acquired brain injury in childhood which of the following is most likely to be impaired?
A. Executive function.
B. Hearing.
C. Motor control.
D. Speech.
E. Vision.

A. Executive function


A four-year-old boy presents with a painful left knee and a rash. He had developed a cold a week prior and had been taking cefaclor syrup for five days. What is the most likely mechanism of this adverse reaction to cefaclor?
A. Delayed type hypersensitivity.
B. Eosinophil degranulation.
C. IgE mediated allergy.
D. Immune complex deposition.
E. Neutrophil activation.

D. Immune complex deposition


A four-year-old boy has had wakings at night for the past six months. His mother describes that she
hears him cry out, and when she goes into his room he is sitting up in bed crying vigorously.
Sometimes he gets out of bed and runs frantically around his bedroom or even around the house,
seemingly trying to get away from something. She describes that once he even tried to get out the
front door. He is not aware of her presence and will eventually lie back down and return to sleep after
about five minutes.
Which of the following is the most appropriate next step in management?
A. Daytime sleep-deprived electroencephalogram (EEG).
B. Magnetic resonance imaging (MRI) scan of the brain.
C. Overnight video EEG.
D. Polysomnography.
E. Sleep diary.

E. sleep diary


A nine-year-old boy presents to the Emergency Department with an intense and prolonged angry
outburst. His mother was unable to manage his behaviour. He has a history of aggressive behaviour
and has been diagnosed with attention deficit hyperactivity disorder (ADHD).
The most likely diagnosis is:
A. Asperger syndrome.
B. bipolar affective disorder.
C. illicit drug use.
D. oppositional defiant disorder.
E. schizophrenia.

D. oppositional defiant disorder.


A six-year-old girl is seen in the Emergency Department after falling from a swing and hitting her head.
The history suggests loss of consciousness at the scene. On examination her Glasgow Coma Score
is 14/15. Head circumference is 47.5 cm (
parietal bone. Her parents say she is “behind at school”. Skull X-ray appearance is shown below.

This most likely diagnosis is:
A. craniosynostosis.
B. hydrocephalus.
C. Langerhans cell histiocytosis.
D. osteopetrosis.
E. periostotic fibrous dysplasia.

A. craniosynostosis.


A six-month-old infant drinks 1000 ml of a standard cow milk formula daily. Approximately how much
energy does the child get per day from his milk intake?
A. 200 kcal (840 kJ)
B. 500 kcal (2100 kJ)
C. 670 kcal (2820 kJ)
D. 810 kcal (3400 kJ)
E. 1000 kcal (4200 kJ)

C. 670 kcal (2820 kJ)


An 11-year-old Caucasian girl presents with progressive weight gain and poor growth velocity over
12 months. On examination she is 66 kg (>97th percentile) and 131 cm tall (
blood pressure is 120/85 mmHg. She has Tanner stage 3 pubic hair, Tanner stage 2 breast
development and some axillary hair. Her profile is shown in the photograph below.

Which is the most appropriate first investigation to make the correct diagnosis for her symptoms?

A. 24-hour urinary free cortisol level.
B. Abdominal ultrasound.
C. Adrenocorticotrophin level.
D. Androstenedione level.
E. Random blood glucose level.

A. 24-hour urinary free cortisol level.


What is the most common comorbid problem associated with school refusal in primary school aged
A. Abdominal migraine.
B. Attention deficit hyperactivity disorder.
C. Depression.
D. Learning difficulties.
E. Separation anxiety.

E. Separation anxiety.


A six-month-old girl is referred to the outpatient clinic for assessment of delayed development. She
will not reach, sit unsupported or roll. She weighs 7.6 kg (50th - 75th percentile), and measures 67cm in
length (50th percentile). Her head circumference is 41 cm (25th percentile). Her head and facial
appearance is shown below.

The most likely reason for this appearance is:
A. coronal synostosis.
B. deformational plagiocephaly.
C. lambdoid synostosis.
D. metopic synostosis.
E. sagittal synostosis.

D. metopic synostosis.


Which of the following problems with language development is characteristic of children with Asperger
A. Articulation difficulties.
B. Expressive language delay.
C. Pragmatic language difficulties.
D. Receptive language delay.
E. Voice production difficulties.

C. Pragmatic language difficulties.


A 32-week gestation infant with ascites is being mechanically ventilated with synchronous intermittent
mandatory ventilation. The ventilator settings are as follows:

Positive inspiratory pressure (PIP) 24 cm H2O

Positive end-expiratory pressure (PEEP) 5 cm H2O

FiO2 80%

Set respiratory rate 30 breaths/minute

Inspiratory time (Ti) 0.3 seconds

At a time when the infant's oxygen saturation is 86%, an arterial blood gas shows:

pH 7.26 [7.34 – 7.43]

Partial pressure of oxygen (pO2) 40 mmHg [50 – 80 mmHg]

Partial pressure of carbon dioxide (pCO2) 48 mmHg [31 – 42 mmHg]

Bicarbonate (HCO3) 21 mmol/L [20 – 26 mmol/L]

A chest X-ray is performed and is shown below:

The most appropriate change to the ventilator settings is:
A. increase fraction of inspired oxygen.
B. increase inspiratory time.
C. increase peak inspiratory pressure.
D. increase positive end expiratory pressure.
E. increase set ventilator rate.

D. increase positive end expiratory pressure.


A six-week-old infant is seen in outpatients for follow-up of a renal abnormality noted prenatally. The
postnatal ultrasound of the right kidney is shown below and a MAG 3 nuclear renal scan shows no
function of this kidney. The left kidney is reported as showing no abnormality.
Which one of the following diagnoses is most consistent with these clinical features?
A. Autosomal dominant polycystic kidney disease.
B. Autosomal recessive polycystic kidney disease.
C. Multicystic dysplastic kidney.
D. Pelviureteric junction obstruction.
E. Vesicoureteric reflux.

C. Multicystic dysplastic kidney


A one-month-old male presents to the Emergency Department with a fever. A suprapubic aspirate is
performed, and initial microscopy reveals > 300 x 103 leukocytes. Which of the following is the most
appropriate initial antibiotic treatment?

A. Amoxicillin plus clavulanic acid.
B. Ampicillin plus gentamicin.
C. Cefotaxime.
D. Cephalexin.
E. Trimethoprim-sulphamethoxazole.

B. Ampicillin plus gentamicin.


A 14-year-old vegan girl presents with severe tiredness. Three weeks previously she was treated for
fever, cough and dyspnoea with a seven day course of amoxycillin.

Laboratory tests include:
Haemoglobin (Hb) 90 g/L [115 – 140 g/L]
Red Cell Count (RCC) 2.6 x 1012/L [3.9 – 5.6 x 1012/L]
Mean Cell Volume (MCV) 97 fL [72 – 88 fL]
White Cell Count (WCC) 5.0 x 109/L [4.0 – 13.0 x 109/L]
Neutrophils 4.3 x 109/L [1.2 – 8.0 x 109/L]
Platelets 150 x 109/L [150 – 400 x 109/L]
Reticulocytes 300 x 109/L [15 – 100 x 109/L]
Monospot negative
Blood film: polychromasia, microspherocytes, rouleaux, agglutination

Which of the following is the most likely underlying cause of this anaemia?

A. Hereditary spherocytosis.
B. Infectious mononucleosis.
C. Mycoplasma pneumoniae infection.
D. Penicillin induced haemolysis.
E. Vitamin B12 deficiency.

C. Mycoplasma pneumoniae infection.

Cold agglutinin disease. M. Pneumoniae and infectious mononucleosis most common causes.


A 15-year-old boy presents with failure to develop puberty. He has a past history of acute
lymphoblastic leukaemia treated with bone marrow transplant and chemotherapy at five years of age.
On examination his height is on the 3rd percentile, his testes are 4 ml bilaterally, and he has
Tanner stage 2 pubic hair.
Investigations include the following:

Luteinising Hormone (LH) 39 IU/L [1 - 8 IU/L]
Follicular Stimulating Hormone 52 IU/L [<12 IU/L]
Testosterone 4.3 nmol/L [8.0 – 35.0 nmol/L]
The most likely cause for his pubertal delay is which of the following?

A. Constitutional delay of growth.
B. Growth hormone deficiency.
C. Hypogonadotrophic hypogonadism.
D. Secondary pituitary tumour.
E. Testicular failure.

E. Testicular failure.


An eight-year-old boy is seen in the Emergency Department with a six-week history of irritability and
the development of subacute proximal weakness.
Examination reveals mild proximal weakness and a rash that is shown below.
What is the most likely diagnosis?

A. Coxsackie B infection.
B. Dermatomyositis.
C. Guillain-Barré syndrome.
D. Polymyositis.
E. Raynaud phenomenon.

B. Dermatomyositis.


You are asked to see a two-day-old baby with feeding difficulties and severe hypotonia. Based on
your assessment, you consider there is a strong clinical likelihood that she has Prader-Willi syndrome.
Which of the following investigations is most likely to confirm your clinical diagnosis?

A. Chromosome analysis.
B. FISH for 15q11.2-13.
C. Methylation analysis of the Prader-Willi critical region.
D. Sequence analysis of the imprinting centre.
E. Uniparental disomy studies of the Prader-Willi critical region.

C. Methylation analysis of the Prader-Willi critical region.


A 15-year-old boy presents with dysphagia and regurgitation of undigested food. His barium swallow
images are shown below.

What is the most likely diagnosis?

A. Achalasia.
B. Eosinophilic oesophagitis.
C. Peptic stricture.
D. Tracheo-oesophageal fistula.
E. Vascular ring.

A. Achalasia.


A six-year-old boy is referred with a history of atopic eczema, chronic sinusitis, recurrent otitis media
and two past admissions for bacterial pneumonia. He has had nine courses of antibiotics prescribed
in the past year.

On examination he is on the third percentile for weight and height. He has no significant
lymphadenopathy, normal tonsillar tissue and his spleen tip is palpable. There is moderate flexural
Laboratory tests include:

Haemoglobin (Hb) 152 g/L [115 – 150 g/L]
Platelets 130 x 109/L [150 – 450 x 109/L]
White Cell Count (WCC) 9.1 x 109/L [1.2 – 8.0 x 109/L]
Neutrophils 4.3 x 109/L [0.5 – 7.0 x 109/L]
Lymphocytes 1.9 x 109/L [2.7 – 12.0 x 109/L]
Eosinophils 2.0 x 109/L [0.0 – 1.0 x 109/L]
IgG 3.4 g/L [7.7 – 11.2 g/L]
IgA <0.1 g/L [0.6 – 1.6 g/L]
IgM 0.1 g/L [0.5 – 1.5 g/L]
IgE 450 KU/L [0 – 250 KU/L]

The most likely diagnosis is:

A. common variable immunodeficiency.
B. hyper IgE syndrome.
C. selective IgA deficiency.
D. Wiskott-Aldrich syndrome.
E. X-linked agammaglobulinaemia.

A. common variable immunodeficiency.


A three-year-old boy develops urticaria, throat tightness and wheeze after ingestion of a dessert containing cashew nuts. He is given adrenaline in the Emergency Department with rapid relief. Skin prick allergy testing was performed to a range of nuts.
Cashew 5 x 5 mm
Histamine control 3 x 3 mm
Normal saline 0 x 0 mm

The likelihood of spontaneous resolution of his cashew allergy is closest to:

A. 5%
B. 20%
C. 50%
D. 70%
E. 90%

B. 20%


A four-month-old infant is referred from a refugee centre for assessment of a neck lump, present since birth. He is feeding well and gaining weight normally. On examination there is a 1 cm x 1 cm mass in the anterior neck; overlying skin is red and warm. A thick discharge is expressed from the lesion.

A photograph of the lesion is shown below.

The most likely diagnosis is:

A. branchial cleft remnant.
B. cystic hygroma.
C. Mycobacterium avium complex.
D. thyroglossal cyst.
E. tuberculosis.

D. thyroglossal cyst.


Conduct disorder relates to persistent maladaptive and anti-social behaviours which can present in childhood or adolescence. The treatment which is best supported by the literature on the treatment of severe conduct disorder is:

A. adolescent group therapy.
B. assertiveness training.
C. cognitive behavioural therapy.
D. multisystemic therapy.
E. risperidone.

D. multisystemic therapy.


A 13-year-old girl presents with intermittent headaches for the last two years. They have become more frequent in recent months and now occur most mornings. A magnetic resonance imaging (MRI) scan is performed and shown below.

The most likely diagnosis is:

A. brainstem glioma.
B. craniopharyngioma.
C. ependymoma.
D. medulloblastoma.
E. pilocytic astrocytoma.

E. pilocytic astrocytoma.


A ten-year-old girl is referred for management of nocturnal enuresis. She has no daytime symptoms but has not been dry at night for any longer than one week since she was a young child. The most appropriate treatment for this child is:

A. desmopressin acetate.
B. enuresis alarm.
C. imipramine.
D. psychological counselling.
E. oxybutinin.

B. enuresis alarm


A seven-year-old boy with a past history of asthma presents to the Emergency Department with a three day history of coryza and increasing shortness of breath. On examination he is very tachypnoeic, with widespread wheeze on auscultation. His temperature is 37.4oC. His chest X-ray is shown below.

This X-ray is most consistent with which of the following diagnoses?

A. Diaphragmatic eventration.
B. Pleural effusion.
C. Pneumothorax.
D. Right lower lobe pneumonia.
E. Right middle and lower lobe collapse.

E. Right middle and lower lobe collapse


The parents of an 18-month-old boy present with concerns that he may have autism. The failure of
attainment of which developmental skill is the best indicator of this diagnosis at this age?

A. Pointing with index finger to something of interest.
B. Remaining focussed on a task for three minutes.
C. Self-feeding with a spoon.
D. Speaking in two-word combinations.
E. Symbolic play.

A. Pointing with index finger to something of interest.


A 13-year-old boy collapses while playing soccer. There is a brief period of loss of consciousness, but he is now awake, alert and oriented, although complaining of a severe headache. A computed tomography (CT) scan of his head is shown below.

Which of the following is the most likely diagnosis?

A. Diffuse cerebral oedema.
B. Extradural haemorrhage.
C. Migraine.
D. Subarachnoid haemorrhage.
E. Subdural haemorrhage

D. Subarachnoid haemorrhage.


A four-year-old boy is reviewed eight hours after ingesting at least 20 ferrous sulphate tablets. Shortly afterwards he developed abdominal pain and vomiting. Specks of blood were noted in the vomitus. These symptoms have now resolved and on examination he is alert, pale and well perfused.

Abdominal X-ray is normal.

The most appropriate next step in management is:

A. activated charcoal.
B. desferrioxamine.
D. endoscopy.
E. whole bowel irrigation.

B. desferrioxamine.

Iron tabs can be seen on AXR.

Indications for IV deferoxamine:

  • Severe symptoms (altered mental status, hemodynamic instability, persistent vomiting and/or diarrhea)
  • Anion gap metabolic acidosis
  • Peak serum iron concentration (SIC) greater than 500 mcg/dL (90 micromol/L)
  • Significant number of pills on abdominal radiograph


A ten-month-old boy presents with the facial rash as shown below. He has had dry skin on his cheeks
for some weeks, and his parents have been applying moisturiser and Mometasone furoate 0.1%.
In addition to oral antibiotics, the most appropriate management now would be to:

A. add topical aciclovir.
B. add topical mupirocin.
C. add topical triclosan.
D. change to hydrocortisone 1% cream.
E. change to pimecrolimus cream.

D. change to hydrocortisone 1% cream.


A previously well sixteen-year-old boy presents to the Outpatient Department with a three week history
of cough. On examination his temperature is 37.8oC and there is reduced air entry in the right upper
lobe. He has no unwell contacts and has not travelled outside Australia since visiting extended family
in the Philippines three years ago. His chest X-ray is shown below.

The most likely infecting organism is:

A. Aspergillus fumigatus.
B. Legionella pneumophila.
C. Mycobacterium tuberculosis.
D. Mycoplasma pneumoniae.
E. Streptococcus pneumoniae.

C. Mycobacterium tuberculosis.


An eight-year-old boy is undergoing investigation for recently recognised mild anaemia,
thrombocytopenia and neutropenia. A photograph of his right thumb is shown below.

The investigation most likely to confirm the underlying diagnosis is:

A. acid sucrose lysis test .
B. bone marrow karyotype.
C. chromosome breakage studies.
D. flow cytometry.
E. urine phosphate to creatinine ratio.

C. chromosome breakage studies.

Fanconi's Anaemia.


A male infant born at 26 weeks gestation, who is now four weeks old, is fully established on enteral
milk feeds which are fortified to a total caloric intake of 150 kcal/kg/day. He had mild hyaline
membrane disease but is now breathing in 23% supplemental oxygen, to maintain oxygen saturations
between 90% and 94%. He is no longer having apnoeas and his only medication is a vitamin
supplement. His birthweight plotted on the 50th percentile and is now plotting between the 3rd and
10th percentile for weight. His blood results are as follows:

Sodium 134 mmol/L [135 – 145 mmol/L]
Potassium 4.7 mmol/L [3.5 – 5.1 mmol/L]
Chloride 98 mmol/L [98 – 110 mmol/L]
Bicarbonate (HCO3) 20 mmol/L [20 – 26 mmol/L]
Haemoglobin (Hb) 10.1 g/dL [13.0 – 18.0 g/dL]
The most likely cause for this infant’s inadequate weight gain is:

A. anaemia of prematurity.
B. high intestinal losses of chloride.
C. high renal losses of sodium.
D. inadequate caloric intake.
E. metabolic acidosis.

C. high renal losses of sodium.