Past Exam Errors 2 Flashcards
A five-year-old is investigated with a fasting study for suspected hypoglycaemia.
Which combination of plasma glucose, insulin, beta hydroxybutyrate (β-OH-butyrate), lactate and cortisol can
best be described as a normal metabolic response to fasting after 18 hours in a five-year-old?
The non-fasting normal range values are shown in [ ] brackets.
Plasma glucose [3.5-8.0 mmol/L] Insulin [15-120 pmol/L] β-OH-butyrate [0.1-0.3 mmol/L] Lactate [0.3-2.0 mmol/L] Cortisol [150-450 mmol/L]
A. 3.1 10 1.5 0.5 500 B. 3.1 10 0.3 0.5 420 C. 3.3 15 1.4 3.8 450 D. 2.4 10 2.1 1.0 650 E. 2.9 15 1.8 1.0 90
A - BGL 3.1 insulin 10 ketones 1.5 lactate 0.5 cortisol 500
Newborn screening programs around the world carry out programs reflecting local prevalence and need.
Which one of the following congenital conditions has the highest prevalence in Australia and New Zealand?
A. Bilateral hearing impairment. B. Cystic fibrosis. C. Galactosaemia. D. Hypothyroidism. E. Neuroblastoma.
A - bilateral hearing impairment. 1/1,000.
CF 1/2,500
Galactosemia 1/50,000
Hypothyroidism (congenital) 1/3,000
Neuroblastoma 1/100,000
Which one of the following types of mutation is most likely to lead to the introduction of a premature stop
codon?
A. 1 base pair insertion in an exon.
B. 1 base pair insertion in the promoter.
C. 2 base pair duplication in an intron.
D. 3 base pair deletion in an exon.
E. 3 base pair inversion in an exon.
A - 1 base pair insertion in an exon. Need to shift reading frame.
Stop codon would need to be in coding region i.e. exon, not intron. Deletion/changes to 3 base pairs maintains reading frame and is less likely.
Dendritic cells are distinguished by an exceptional ability to carry out which one of the following immune
functions?
A. Antigen presentation. B. Chemokine secretion. C. Cytokine secretion. D. Immunoglobulin secretion. E. Phagocytosis.
A - APC
Which one of the following poses the greatest threat to validity in a longitudinal cohort study? A. Confounding. B. Data collection intervals too long. C. Data collection intervals too short. D. Loss to follow-up. E. Selection bias.
D - loss to follow up
The use of artificial surfactant has been shown to reduce the incidence of which one of the following
complications of prematurity?
A. Chronic lung disease. B. Periventricular haemorrhage. C. Pneumothorax. D. Retinopathy of prematurity. E. Symptomatic patent ductus arteriosus.
C - pneumothorax
The correlation between television violence and aggressive behaviour has been shown to be highest for
which one of the following age groups?
A. Pre-school. B. Primary school. C. Early adolescence. D. Late adolescence. E. Young adults.
A - pre-school
Which one of the following chemotherapeutic agents has activity in the S phase of the cell cycle only?
A. Cisplatin. B. Etoposide (VP-16). C. Ifosfamide. D. Prednisolone. E. Vinblastine.
D - prednisolone
Antimetabolites would be the more common/logical answer? None of the agents listed are antimetabolites.
Some antimetabolites that are commonly used to treat cancer include: 6-mercaptopurine. fludarabine. 5-fluorouracil. gemcitabine. cytarabine. pemetrexed. methotrexate.
Others
Cisplatin is an alkylating agent, and works independently of the cell cycle.
Ifosfamide is cell phase nonspecific as well.
Etoposide’s mechanism of action is to cause single-strand and double-strand breaks in DNA through interaction with DNA topoisomerase II, inducing arrest in the G2-phase of the cell cycle.
Vinblastine is also an alkylating agent, and is cell cycle phase specific; it binds to microtubular proteins in the mitotic spindle, thereby preventing cell division during metaphase.
If one identical twin develops schizophrenia, what is the lifetime risk that the other twin will also develop schizophrenia? A. 25%. B. 50%. C. 75%. D. 90%. E. >99%.
B - 50%
You are providing safety advice to the parents of a six-year-old child of average height and weight.
Which one of the following is the most appropriate car seating arrangement for this child, in order to
decrease the chance of injury in a motor vehicle accident?
A. Back seat; booster; seat belt. B. Back seat; no booster; seat belt. C. Front or back seat; booster; seat belt. D. Front seat; booster; seat belt. E. Front seat; no booster; seat belt.
A - back seat, booster, seat belt.
Vicroads:
Children under 4 years old must travel in a rear facing or forward facing child restraint.
Children aged between 4-7 years must travel in a forward facing child restraint or a booster seat.
Children aged between 7 and 16 are required to use a booster seat or adult seat belt when travelling in a vehicle.
NSW:
National child restraint laws
- Children up to the age of six months must be secured in an approved rearward facing restraint
- Children aged from six months old but under four years old must be secured in either a rear or forward facing approved child restraint with an inbuilt harness
- Children under four years old cannot travel in the front seat of a vehicle with two or more rows
- Children aged from four years old but under seven years old must be secured in a forward facing approved child restraint with an inbuilt harness or an approved booster seat
- Children aged from four years old but under seven years old cannot travel in the front seat of a vehicle with two or more rows, unless all other back seats are occupied by children younger than seven years in an approved child restraint or booster seat
- Children aged from seven years old but under 16 years old who are too small to be restrained by a seatbelt properly adjusted and fastened are strongly recommended to use either a forward-facing seat with an in-built harness for older children, an approved booster seat, or an approved child safety harness in conjunction with the vehicle’s seatbelt
- Children in booster seats must be restrained by a suitable lap and sash type approved seatbelt that is properly adjusted and fastened, or by a suitable approved child safety harness that is properly adjusted and fastened.
The diagram below shows cumulative quantal dose-response curves for a hypothetical drug (drug X). The
Y-axis represents the percentage of the population studied who: for curve (a) achieved the desired
therapeutic effect at a given dose; and for curve (b) experienced the most important toxic effect at a given
dose.
Based on this information, the best estimate of the therapeutic index of drug X is approximately: A. 0 B. 0.3 C. 0.7 D. 1.0 E. 3.0
E - 3.0
TI = Toxic50/Therapeutic50
Toxic50 = dose at which 50% have toxic effect
Therapeutic 50 = dose at which 50% have therapeutic effect
The impact of an intervention in clinical trials and in systematic reviews can be expressed in a number of
ways. One increasingly used format is the number needed to treat (NNT) which indicates how many patients have to be treated with the intervention of interest compared to the control intervention in order to achieve one successful outcome.
In a systematic review of optimal home-management for asthma, the intervention was found to produce a
50% reduction in hospitalisation for asthma. Approximately 10% of patients in the control group required hospitalisation compared to approximately 5% of those who received optimal home-management.
Which one of the following is the best estimate of the NNT for this intervention? A. 2. B. 5. C. 10. D. 20. E. 50.
D - 20
When a study outcome is expressed as a percent, the number needed to treat (NNT) is the inverse of the absolute risk reduction (ARR) expressed as a decimal. The example below compares an event rate of 26% versus 16%:
ARR=(Control event rate)−(Experimental event rate)
ARR=0.26−0.16=0.1
NNT=1/ARR
NNT=1/0.1 = 10patients
In the question, 0.1-0.05 = 0.05, 1/0.05 = 20
A previously well term infant develops multifocal clonic seizures at 72 hours of age. Examination reveals a
bulging fontanelle. A cranial ultrasound shows a large intraventricular haemorrhage. Investigation of the
clotting profile shows:
platelet count 200 x 109/L [150-400]
prothrombin time (PT) 100 seconds [10-24]
activated partial thromboplastin time (APTT) 35 seconds [28-79]
The most likely diagnosis is: A. haemorrhagic disease of the newborn. B. factor VII deficiency. C. factor VIII deficiency. D. factor XII deficiency. E. von Willebrand disease.
B - factor VII deficiency
HDN = vitamin K deficiency = affects factors 2, 7, 9, 10 = should affect both PT and APTT.
In the human foetus near term, the ratio of the output of the right ventricle compared to the left ventricle is closest to: A. 1:2 B. 1:1.5 C. 1:1 D. 2:1 E. 4:1
D - 2:1
Which one of the following pharmacokinetic parameters is most important in the optimal prescribing of beta-
lactam antibiotics?
A. The peak concentration/minimum inhibitory concentration (MIC) ratio.
B. Area under the plasma concentration versus time curve (AUC).
C. The AUC/MIC ratio.
D. Time above the MIC.
E. Both AUC/MIC ratio and peak concentration/MIC ratio.
D - time above the MIC
Alison’s notes - patterns of antimicrobial activity
Type I - Concentration-dependent killing
• As concentration of an antibiotic increases, rate of killing increases (best when peak 10x MIC)
• Eliminate bacteria more rapidly when concentrations significantly above MIC
• Significant post-antibiotic effect with duration dependent on peak
• Peak concentration limited by toxicity
Examples: Aminoglycosides, Fluoroquinolones
Goal of therapy: maximise concentrations (peak/MIC)
Type II - Time-dependent killing
• Mainly dependent on time at binding site to kill organisms
• Increasing concentration will not increase effectiveness (maximum killing rate at 2-4x MIC)
• Amount of time above MIC in any one dosing interval is best predictor of clinical response (dosing interval important)
• Minimal to NO post-antibiotic effect
Examples: Penicillins, Cephalosporins, Carbapenems, Erythromycin, Linezolid
Goal: maximise duration of exposure (time above MIC)
Type III - Time and concentration dependent
• Combination of the two
• Rate of bacterial killing related to both time above MIC and total exposure of antibiotic to organism
Examples: Azithromycin, Vancomycin, Clindamycin, Tetracyclines
Goal: maximise amount of drug (24hr AUC/MIC)
Anorexia nervosa is accompanied by significant hormonal changes. Which one of the following is least likely to be found in an adolescent girl with anorexia nervosa? A. Increased plasma cortisol. B. Increased plasma growth hormone. C. Increased plasma oestradiol. D. Normal plasma prolactin. E. Normal plasma thyroxine (T4).
D - normal plasma prolactin. ?Outdated… there seems to be an implication that this was theorised/expected but hasn’t been proven.
Google searches:
- The role of prolactin in anorexia nervosa is controversial and both hyperprolactinaemia and normoprolactinaemia were reported in patients with anorexia nervosa.
- Theoretically, one would expect to find increases in prolactin secretion in patients with anorexia nervosa: the evidence for this is reviewed. However, relevant work to date seems to indicate that this is not so. These paradoxical findings are discussed, and areas of further research are outlined.
Uptodate - endocrine complications of AN.
Reproductive — Suppression of the hypothalamic-pituitary-ovarian axis results in hypogonadotropic hypogonadism with amenorrhea, estradiol deficiency, and infertility. Low LH, low oestradiol, low testosterone.
Adrenal — Increased hypothalamic-pituitary-adrenal (HPA) activity in the setting of the stress of chronic starvation leads to hypercortisolemia.
Growth hormone — Although growth hormone (GH) levels are high in AN, levels of the downstream hormone insulin-like growth factor-1 (IGF-1) are low, indicating a state of “resistance” to GH due to chronic starvation.
Thyroid — Women with AN often have a “euthyroid-sick” pattern of thyroid function tests due to chronic undernutrition: triiodothyronine (T3) levels are low, and reverse T3 (rT3) levels and the ratio of thyroxine (T4) to T3 are high. Thyroid-stimulating hormone (TSH) and T4 levels may be normal or low.
●Basal levels of oxytocin, a hormone that is involved in a range of physiologic processes including social behaviors, modulation of anxiety and depressive symptoms, energy homeostasis, and bone metabolism, are decreased.
A five-year-old boy was successfully treated for a testicular germ cell tumour at two years of age. Therapy
consisted of cisplatin, etoposide (VP-16) and bleomycin.
The most likely long-term complication of the therapy is: A. high tone hearing deficit. B. pulmonary fibrosis. C. renal failure. D. secondary leukaemia. E. sterility.
A - high tone hearing deficit. In general:
- platinum compounds a/w ototoxicity and nephrotoxicity
- etoposide
- bleomycin: pulmonary fibrosis
Uptodate
One study of cisplatin ototoxicity: At a median 51 months following chemotherapy, hearing loss was found in 80 percent of the survivors, and 18 percent had severe or profound hearing loss. Tinnitus (which was reported by 40 percent of survivors) was also significantly correlated with reduced hearing at each frequency.
Other complications:
Cisplatin: The range of cisplatin-induced neurotoxicity includes peripheral neuropathy, ototoxicity (hearing impairment and tinnitus), vestibulopathy, and encephalopathy; the most common are peripheral neuropathy and ototoxicity.
Etoposide — Etoposide (VP-16) is a topoisomerase II inhibitor that is used extensively in the treatment of lung cancer, germ cell tumors, and refractory lymphomas. Although neurotoxicity is uncommon, even in high doses, peripheral neuropathy (less than 2 percent), mild disorientation, seizures, transient cortical blindness, and optic neuritis have been reported.
Bleomycin (lung injury): Rates of any grade of pulmonary toxicity range from 5 to 16 percent, and rates of fatal pulmonary toxicity have been in the range of 0 to 1 (for three courses) and 0 to 3 percent (for four courses). However, more recent data suggest that the overall risk of clinically-apparent and fatal bleomycin-induced lung injury may be lower.
Which one of the following is least likely to present with acute flaccid paralysis? A. Bacterial meningitis. B. Enterovirus 71 meningoencephalitis. C. Guillain-Barré syndrome. D. Infant botulism. E. Poliomyelitis.
A - meningitis. Acute flaccid paralysis is a feature of all the others.
●Encephalitis – Encephalitis is defined as inflammation of the brain parenchyma and is manifested by signs of neurologic dysfunction. Characteristic clinical features include altered mental status (decreased level of consciousness, lethargy, personality change, unusual behavior) lasting at least 24 hours, seizures, and/or focal neurologic signs (eg, cranial nerve palsies, abnormal movements, weakness; 50 to 60 percent), often accompanied by fever, headache, nausea, and vomiting.
●Meningitis – Meningitis is inflammation of the meninges and is typically manifested by fever, headache, nausea, vomiting, photophobia, and stiff neck.
GBS: sudden onset of weakness, usually affecting lower limb, ascending paralysis, symmetrical weakness, pain a prominent feature, 50% sensory involvement.
Infant botulism: p/w floppy infant with poor feeding, weak cry, hypotonia, constipation. General botulism: symmetric descending flaccid paralysis, bulbar musculature initially.
Poliomyelitis: Poliovirus is a species of human enterovirus. A small fraction of patients with poliovirus infection develop central nervous system (CNS) infection -> death of motor neuron -> paralysis. Weakness may vary from one muscle or group of muscles, to quadriplegia, and respiratory failure. Tone is reduced, nearly always in an asymmetric manner. Proximal muscles usually are affected more than distal ones, and legs more commonly than arms. Reflexes are decreased or absent. The sensory examination is normal.
The chronic administration of a thiazide diuretic is associated with all of the following except: A. hypercalciuria. B. hyperglycaemia. C. hyperuricaemia. D. hypochloraemic alkalosis. E. normal serum magnesium.
A - hypercalciuria. Thiazides block Na/Cl cotransported in the DCT.
Thiazides are a potential treatment for hypercalciuria. The overall affect in the kidney in response to diuretics is the increase reabsorption of sodium, and therefore calcium, lowering calcium levels in urine.
Uptodate
Most of the filtered calcium is reabsorbed, an effect that occurs throughout the nephron. Calcium reabsorption in the proximal tubule can be affected by the patient’s volume status as enhanced proximal sodium and water reabsorption due to volume depletion leads to increased passive proximal calcium reabsorption.
Proposed mechanisms — Two main mechanisms have been proposed to explain the effect of thiazides on calcium excretion, but their relative importance is uncertain:
●Increased proximal sodium and water reabsorption due to volume depletion, which leads to increased passive proximal calcium reabsorption
●Increased distal calcium reabsorption at the thiazide-sensitive site in the distal tubule and connecting segment
Diuretic therapy has variable effects on urinary calcium excretion according to the site of action:
●Calcium excretion is increased by osmotic diuretics (such as mannitol) and the carbonic anhydrase inhibitor acetazolamide.
●Calcium excretion is increased by loop diuretics due to diminished reabsorption. This effect may be beneficial in selected patients with hypercalcemia, but can be deleterious in neonates, leading to the development of nephrocalcinosis.
●Calcium excretion is diminished by thiazide-type diuretics by as much as 50 to 150 mg (1.3 to 3.8 mmol) per day due to increased reabsorption.
Which one of the following capsular polysaccharides of Neisseria meningitidis is least immunogenic? A. A. B. B. C. C. D. W-135. E. Y.
B - B
Which one of the following children is least likely to have language skills in the normal range at age five
years?
A. 14 months old; conductive hearing loss (pure tone average 30db hearing loss bilaterally) at
successive hearing tests aged 10 and 13 months; no words.
B. 18 months old; no words.
C. 24 months old; 40 single words; no two-word combinations.
D. 30 months old; acquired severe hearing loss due to meningitis aged 24 months; normal intelligence.
E. 36 months old; many words; not using grammatical markers of tense and person.
E - 36 months old, many words, not using grammatical markers of tense or person.
Which one of the following is the major cause of physiologic neonatal jaundice?
A. Decreased bilirubin uptake by the hepatocyte.
B. Decreased hepatic bilirubin conjugation.
C. Decreased hepatic excretion of bilirubin.
D. Increased de novo bilirubin synthesis.
E. Increased enterohepatic circulation.
D - increased de novo bilirubin synthesis
In X-linked severe combined immunodeficiency (SCID), the affected gene codes for the common cytokine
receptor gamma chain whose principal function is:
A. nuclear regulation in T and B cells.
B. rearrangement of the T and B cell receptors.
C. signal transduction in T and B cell receptors.
D. T cell-induced immunoglobulin isotype switching.
E. transduction of gamma C-chain-dependent intracellular signals.
C - signal transduction in T and B cell receptors
Cisapride can cause prolonged Q-T interval and cardiac arrhythmia when used in combination with other drugs. Which one of the following drugs would be most likely to cause arrhythmias in a patient taking cisapride? A. Amoxycillin. B. Cefaclor. C. Erythromycin. D. Metronidazole. E. Trimethoprim-sulfamethoxazole.
C - erythromycin. Note TMP/SMX listed in Parks as a cause, not in the table on uptodate.
MRCPCH - acquired causes of QT prolongation
Antibiotics: erythromycin, clarithromycin, azithromycin, TMP/SMX
Antifungals: azoles (flucon, itracon, ketocon)
Antihistamines: terfenadine
Antidepressants: TCAs
Antipsychotics: haloperidol, resperidone, chlorpromazine
Antiarrhythmic agents
Diuretics (due to K loss): furosemide
Electolyte disturbances: hypokalaemia, hypocalcaemia, hypomagnesaemia
Underlying medical conditions: complete AV block, severe bradycardia, sick sinus syndrome, myocardial dysfunction, CHF, myocarditis, endocrinopathies (hyperparathyroid, hypothyroid, phaechromocytoma), neurologic (encephalitis, head trauma, stroke, SAH), nutritional (alcohol, anorexia, starvation)
One of two siblings is diagnosed with type 1 (insulin-dependent) diabetes mellitus (IDDM). There is no family
history of IDDM. What is the approximate risk that the other sibling will develop IDDM?
A. 1%.
B. 6%.
C. 12%.
D. 25%.
E. 50%.
B - 6%
A Southern blot on tumour tissue from a patient with Burkitt lymphoma is shown above. The signal in the
tumour tissue indicates which one of the following?
A. Amplified DNA.
B. Amplified messenger RNA.
C. Amplified protein.
D. Increased half-life of DNA.
E. Increased half-life of messenger RNA.
A - amplified DNA
Southern blot = DNA
Northern = RNA
Western = protein
Southern was first (persons name), then the others (opposite Southern second, then Western). Think DNA->RNA->protein.
The electrocardiogram (ECG) shown above was obtained from a three-year-old girl with a systolic murmur. Which one of the following is the most likely diagnosis?
(superior axis)
A. Perimembranous ventricular septal defect. B. Persistent ductus arteriosus. C. Primum atrial septal defect. D. Pulmonary valve stenosis. E. Subaortic stenosis.
C - primum ASD
ECG findings
ASD: Primum = superior axis, Secundum = RBBB and 1st degree block
TA has superior axis as well, but cyanotic lesion.
In general, compared with autosomal dominant disorders, autosomal recessive disorders are:
A. more severe more variable within families more likely to be due to new mutations
B. more severe more variable within families less likely to be due to new mutations
C. more severe less variable within families less likely to be due to new mutations
D. less severe more variable within families more likely to be due to new mutations
E. less severe less variable within families less likely to be due to new mutations
C - more severe, less variable within families, less likely to be due to new mutations
Which one of the following is the least important cause of impaired gas exchange in meconium aspiration syndrome? A. Alveolar oedema. B. Bacterial infection. C. Bronchiolar obstruction. D. Pulmonary hypertension. E. Surfactant dysfunction.
B - bacterial infection. Causes chemical pneumonitis, as intrauterine environment sterile.
MRCPCH - MAS
RFs: term or post term, SGA, perinatal asphyxia (fetal distress).
Rare in preterms
Major effects on lung function:
- Airway blockage: increased airway resistence with ball-valve mechanism and gas trapping, high risk of pneumothorax
- Chemical pneumonitis
- Increased risk of infection: E. coli is most common
- Surfactant deficiency: lipid content of meconium displaces surfactant from alveolar surface, PPHN
CXR changes begin as patchy infiltration and hyperinflation. A more homogenous opacification of the lung fields develops of 48 hours as chemical pneumonitis becomes a problem.
No evidence for routine suction if baby is vigorous and otherwise in good condition.
A 900 g, 26-week gestation neonate receiving neonatal-intensive care develops systemic sepsis on day
seven. Klebsiella pneumoniae is grown from the blood cultures with the following sensitivities:
ampicillin resistant
cefotaxime resistant
imipenem sensitive
gentamicin resistant
amikacin sensitive
The most likely mode of resistance of this organism is:
A. altered binding proteins.
B. chromosomally-mediated resistance.
C. extended spectrum beta lactamase production.
D. inducible beta lactamase production.
E. intrinsic resistance.
C - extended spectrum beta lactamase
Google searching:
ESBL producing bacteria, in order of frequency:
- E. coli (67%)
- Klebsiella pneumoniae (25%)
- Pseudomonas, acinetobacter, enterobacter (8-9% together)
The following pharmacokinetic data are provided for five drugs. Drug Volume of distribution (L) Plasma half-life (hr) A 1190 21 B 4620 600 C 70 22 D 7 6 E 126 11 Which of the drugs is most likely to have the slowest rate of clearance from plasma? A. Drug A. B. Drug B. C. Drug C. D. Drug D. E. Drug E.
D - drug D with L=7 and T1/2=6
Alison’s notes:
Clearance=Vd/T0.5
A 16-year-old girl with schizophrenia has been commenced on risperidone.
Which one of the following is the least likely side-effect?
A. Increased dream activity.
B. Menstrual irregularities.
C. Muscle stiffness.
D. Somnolence.
E. Weight loss.
E - weight loss
Weight gain is significant side effect of atypical antipsychotics.
EPSE are the key SE of typical antipsychotics.
T lymphocytes expressing both CD4 and CD8 on the cell surface are most likely to be found in which one of
the following anatomical locations in healthy individuals?
A. Bone marrow.
B. Lymph nodes.
C. Peripheral blood.
D. Spleen.
E. Thymus.
E - thymus
The early T cell progenitor (first step in differentiation) migrates from the bone marrow to the thymus. The rest of the T cell development occurs in the thymus, including double negative and double positive stages (referring to CD4 and CD8).
Which one of the following cardiac conditions is most commonly associated with neurofibromatosis? A. Aortic root dilatation. B. Cardiac rhabdomyomata. C. Coarctation of the aorta. D. Pulmonary stenosis. E. Supravalvular aortic stenosis.
D - pulmonary stenosis
Cardiology manifestations of NF1 are pulmonary stenosis and coarctation.
Other causes of PS: Noonans (valvular), Williams (peripheral), DiGeorge, Alagille (peripheral), congenital rubella (peripheral).
NF1:
- chromosome 17, 50% sporadic, variable expression
- features:>6 CALM, >2 lisch nodules, auxillary freckling, optic glioma, >2 neurofibroma / 1 plexiform neurofibroma, osseous lesion, first degree relative.
For males entering puberty at an average age and height, the increase in height (cm) from the onset of puberty to final height is closest to: A. 17. B. 21. C. 25. D. 29. E. 33.
D - 29cm
Which immunological mechanism is the major cause of the destruction of the small intestinal villous
architecture in coeliac disease?
A. Activation of B lymphocytes.
B. Activation of T lymphocytes.
C. Secretion of anti-endomysial antibodies.
D. Secretion of antigliadin antibodies.
E. Secretion of tissue transglutaminase antibodies.
B - activation of T lymphocytes
A nine-year-old girl presents with obesity. Her height is on the 10th percentile, weight on the 97th
percentile and she has a round face. Shortening of the fourth metacarpals bilaterally are found and
confirmed by X-ray.
Which finding would be most helpful in establishing a diagnosis of pseudohypoparathyroidism?
A. Basal ganglia calcification.
B. Increased fasting plasma insulin/glucose ratio.
C. Increased plasma calcium.
D. Increased serum alkaline phosphatase.
E. Increased serum parathyroid hormone.
E - increased serum PTH
MRCPCH
Autosomal dominant. End organ resistance to raised levels of PTH.
Abnormal phenotype of short stature, obesity, ID, round face, short neck, shortened 4th/5th metacarpals.
High PTH and phosphate, low calcium.
A two-day-old neonate presents with copious purulent eye and nose discharge. Laboratory
examination is performed to diagnose the organism involved.
Which one of the following types of organism would carry the worst prognosis if not treated
immediately?
A. Gram-negative coccobacillus.
B. Gram-negative diplococcus.
C. Gram-positive bacillus.
D. Gram-positive coccus.
E. Intra-cytoplasmic inclusion bodies.
B - GN diplococcus
Notes
Neisseria = GN diplococci
Others
GN coccobacillus - enterobacter (e.g. E coli), Hib, pertussis, pseudomonas, legionella, klebsiella
GPB - Diptheria, listeria, clostridia, mycobacteria
GPC - staph, strep
Inclusion bodies - viral
A three-year-old boy is referred with a history of snoring loudly over the previous nine months. On
history no obstructive apnoea has been noted by his mother. A lateral X-ray of neck shows only
moderate adenoidal hypertrophy with a clearly patent airway. A polysomnogram is reported as
showing an obstructive respiratory disturbance index of 5 events/hr with oxygen desaturation
decreases of 4% of baseline, and an arousal index of 20 events/hr [<10] with reduced rapid eye
movement (REM) sleep.
The most appropriate management of this child is:
A. adeno/tonsillectomy.
B. continuous positive airway pressure therapy.
C. inhaled nasal steroids.
D. reassurance.
E. supplemental oxygen.
A - Ts and As
Uptodate
Obstructive sleep apnea (OSA) is characterized by episodes of complete or partial upper airway obstruction during sleep, often resulting in gas exchange abnormalities and arousals, which disrupt sleep. The condition exists in 2 to 5 percent of children and can occur at any age. Untreated pediatric OSA is associated with behavioral and learning problems; in more severe cases, it can be associated with impaired growth (including failure to thrive) and cardiovascular complications. Early diagnosis and treatment may decrease morbidity. Treatment decisions are individualized and depend upon findings from a comprehensive evaluation, including nighttime sleep disruption, daytime dysfunction, physical examination findings, and sleep study findings.
OSA is typically defined by clinically relevant symptoms and an apnea hypopnea index (AHI) >1 or hypoventilation (carbon dioxide >50 mmHg for >25 percent total sleep time) as determined on PSG.
Referral to a specialist for adenotonsillectomy evaluation is generally indicated for otherwise healthy children who have OSA and adenotonsillar hypertrophy (including ≥1+ tonsils). For otherwise healthy children with mild or moderate OSA confirmed by PSG (AHI >1 and <10), watchful waiting with supportive care is a reasonable alternative to adenotonsillectomy. For patients with minimal adenotonsillar tissue or a strong preference for a nonsurgical approach, positive airway pressure therapy is an alternative to adenotonsillectomy.
A two-month-old boy presents with tachypnoea and poor feeding. He is afebrile. His respiratory rate
is 65/minute with mild intercostal recession, his heart rate is 180/minute and his liver is palpable 4 cm
below the right costal margin. No other abnormalities are identified on clinical examination. His
electrocardiogram (ECG) is shown below.
Which one of the following is the most likely diagnosis? A. Anomalous left coronary artery. B. Dilated cardiomyopathy. C. Hypertrophic cardiomyopathy. D. Myocarditis. E. Supraventricular tachycardia.
E - SVT
Others
ALCAPA - STE + inverted T waves aVL, V5, V6, presents 6-8 weeks when PVR drops, unsettled with feeds FTT and cardiomegaly.
Dilated cardiomyopathy - multiple transfusions, recent virus, family hx, ECG with evidence of ischaemia, unrecognised tachycardia (exclude ALCAPA on TTE)
Hypertrophic cardiomyopathy - history of sudden unexplained death or cardiomyopathy or myopathy, IDM, more suggestive of metabolic cause, ECG with short PR and giant complexes, QRS-T axis dissociation
Myocarditis - Long PR, low amplitude QRS / T waves
In which one of the following clinical settings is there the best evidence that prophylactic antibiotics
protect against infection?
A. Cerebrospinal fluid shunt insertion.
B. Chest drain insertion for pneumothorax.
C. Occipital skull fracture.
D. Umbilical artery catheterisation.
E. Urinary catheterisation.
A - cerebrospinal fluid shunt insertion
A 14-year-old girl presents to the emergency department with a 12-hour history of a blistering rash.
The rash is extremely itchy and is spreading up her arm. She is otherwise well and afebrile. A history
is obtained that she had been gardening on the day prior to the rash developing. A diagnosis of an
allergic contact dermatitis is made.
Which one of the following is the most appropriate initial therapy? A. Intravenous antihistamines. B. Oral antihistamines. C. Oral corticosteroids. D. Subcutaneous adrenaline. E. Topical corticosteroids.
C - oral corticosteroids
Uptodate
Allergic contact dermatitis (ACD) is an acquired, inflammatory reaction of the skin that requires absorption of antigen from the skin surface and recruitment of previously sensitized, antigen-specific T lymphocytes into the skin (delayed type hypersensitivity).
Allergic contact dermatitis (ACD) is commonly encountered by the practicing clinician. The most common clinical expression is an eczematous dermatitis that can be mild to severe, acute and short lived, or chronic. The management of ACD is based upon the identification of the offending allergen, avoidance of exposure, use of safe alternatives, and treatment of symptoms.
Oral corticosteroids are the first line treatment for ACD involving >20 percent of the body surface area or for acute ACD involving the face, hands, feet or genitalia if quick relief is desired (eg, involvement of the eyelids).
Others
- Topical corticosteroids are the first line treatment for localized ACD
- Adrenaline for anaphylaxis
- Because it is T lymphocyte driven, antihistamines have no role
A 12-year-old boy with cystic fibrosis presents with a six-week history of increased cough and some
wheeze. He has received a two-week course of oral amoxycillin-clavulanic acid, followed by two
weeks of oral ciprofloxacin without any improvement.
His chest X-ray six months ago is shown below (A) with his recent X-ray (B).
[Acute right perihilar opactiy]
Which one of the following is the most likely cause of his deterioration?
A. Allergic broncho-pulmonary aspergillosis.
B. Atelectasis due to mucus plugging.
C. Burkholderia cepacia infection.
D. Staphylococcus aureus infection.
E. Tuberculosis.
A - ABPA
MRCPCH
Episodic wheezing, low grade fever, brown sputum, eosinophilia, transient pulmonary infiltrates. Usually in children with CF or asthma. Treat with steroids.
Uptodate
Allergic bronchopulmonary aspergillosis (ABPA) is a complex hypersensitivity reaction in response to colonization of the airways with Aspergillus fumigatus that occurs almost exclusively in patients with asthma or cystic fibrosis (CF). In chronic cases, repeated episodes of bronchial obstruction, inflammation, and mucoid impaction can lead to bronchiectasis, fibrosis, and respiratory compromise.
Although invasive fungal disease is rare in patients with CF, allergic bronchopulmonary aspergillosis (ABPA) is increasingly recognized in CF patients. It can be difficult to distinguish between ABPA and the progressive pulmonary disease that is typical in CF because the symptoms and radiographic features are often similar.
In most CF centers, patients are screened with annual evaluation of total serum IgE; a sudden increase should prompt further investigation for possible ABPA. Patients should also be evaluated for ABPA if they have a marked exacerbation of wheezing or otherwise unexplained deterioration in lung function despite antibiotic therapy.
A three-month-old boy presents with tachypnoea and failure to thrive. On examination he is noted to
have a respiratory rate of 60/minute with intercostal and subcostal recession. The liver is palpable
4 cm below the right costal margin. The chest is clear and no murmurs are audible. The oxygen
saturation is 89% in room air but increases to 95% with 1 L of subnasal oxygen. His chest X-ray is
shown below.
Which one of the following is the most likely diagnosis?
A. Bronchiolitis.
B. d-transposition of the great arteries and ventricular septal defect.
C. Primary pulmonary lymphangiectasia.
D. Total anomalous pulmonary venous return.
E. Truncus arteriosus.
D - TAPVR
MRCPCH
Pulmonary veins drain to either SVC/innominate vein (supracardiac) or liver/IVC (infracardiac). Uncommon. NOT duct dependent.
If obstructed -> presents day 1-7 with cyanosis and collapse.
NO MURMUR.
Signs of right heart failure, breathless, acidotic.
May however present up to 6 months if unobstructed, with murmur or heart failure.
ECG normal in neonate. CXR normal or snowman sign.
Bronchiolitis - infective features e.g. fever, coryza, very unlikely to have a clear chest.
D-TGA with VSD - murmur
C -
E - cyanotic at birth, heart failure in weeks, bounding pulses, harsh murmur
A three-year-old boy is evaluated because of longstanding hypotonia, delayed motor milestones and
elevated creatine kinase (CK). Family history revealed that during an anaesthetic, his father
developed fever and muscle rigidity. A muscle biopsy was performed and is shown below. The
section is stained with NADH-trichrome.
Which one of the following is the most likely diagnosis? A. Central core myopathy. B. Duchenne muscular dystrophy. C. Myotonia congenita. D. Nemaline myopathy. E. Spinal muscular atrophy.
A - central core myopathy
Uptodate.
Congenital myopathies are a heterogenous group of hereditary primary muscle disorders that are present from birth, although their onset may be delayed until later in infancy or early childhood. The most common of these rare disorders are nemaline myopathy, central core disease, centronuclear (myotubular) myopathies, and congenital fiber type disproportion.
Congenital myopathies share some common features, though severity is highly variable. Affected individuals usually present at birth or in infancy with hypotonia, weakness, hypoactive deep tendon reflexes, delayed motor milestones, and normal intelligence.
These conditions are caused by genetic abnormalities of muscle development.
Features: neonates, hypotonia+muscle weakness, reflexes present but reduced, predisposition to malignant hyperthermia, usually CK is normal.
These days diagnosis is with genetic testing/sequencing. Muscle biopsy stained with NADH is sometimes valuable.
Others:
- DMD
- Myotonia congenita: Defect in chromosome 7, affects chloride channels in muscles, hypertrophy with no weakness, improves with exercise
- Nemaline: The characteristic rod bodies are best seen with modified Gomori trichrome staining [13]. With this technique, they appear red against a blue-green myofibrillar background.
- SMA: 5q11, regression, proximal myopathy, fasciculations, no reflexes, hypotonia with facial sparing, CK normal
Tacrolimus administration after renal transplantation is least likely to cause which of the following? A. Diabetes mellitus. B. Hypercholesterolaemia. C. Hypomagnesaemia. D. Seizures. E. Tremors.
B - hypercholesterolaemia
Common side effects are hyperglycaemia, renal impairment/AKI, and neurological e.g. tremors, seizures. Diabetes post transplant is common, multifactorial, and incompletely understood.
Other A/E
- hyperkalaemia (hyporenin/hypoaldosterone type 4 RTA)
- hypersensitivity
- HTN
- infection
- malignancy
- hyperkalemia, hypomagnesemia, hyperchloremic metabolic acidosis, hyperuricemia (due to tubular functional alterations)
A seven-year-old girl is referred to the outpatients department for the evaluation of wheezing episodes
which have occurred every month during the previous three months. She was born at 24 weeks
gestation, ventilated for one month and was on supplemental oxygen for a further 12 weeks. Her
clinical examination is normal. Her baseline lung function tests showed the following:
forced vital capacity (FVC) 80% predicted
forced expiratory volume in one second (FEV1) 70% predicted
maximum mid-expiratory flow (MMEF) 30% predicted
She was treated with prednisolone for two weeks (1 mg/kg/day). Repeat lung function tests post
Ventolin were:
FVC 83% predicted
FEV1 75% predicted
MMEF 40% predicted
Her histamine challenge demonstrated a fall in FEV1 of 25%.
Which one of the following is the most likely diagnosis? A. Asthma. B. Bronchial stenosis. C. Bronchomalacia. D. Bronchopulmonary dysplasia. E. Reflux aspiration.
D - BPD
FVC 80-120% = normal.
FEV1/FVC = 87.5% which is normal.
No reversibility with bronchodilator (needs to be 12%+).
Positive histamine challenge (>15-20%).
Essentially normal lung function aside from positive histamine challenge. ?Histamine challenge not super valuable:
“The percentage of asthmatics with bronchial hyperresponsiveness, i.e. sensitivity to the test, increased towards 100% on inhaling increasing concentrations of histamine, but this was accompanied by a decrease in specificity and predictive values of positive test in regard to the diagnosis of asthma. However, lower concentrations of histamine may be preferable in order to distinguish between asthma and non-asthma in population samples, as inhalation of 2.4 mg.ml-1 and provocative concentration producing a 20% fall in forced expiratory volume in one second (FEV1) (PC20) provided an acceptable sensitivity (57%), specificity (98%), and predictive value of a positive test (60%). We conclude that as regards the diagnosis of asthma, a low predictive value confirms that the bronchial challenge test plays only a supplementary, but valuable, role in detecting the disease in population samples.”
Given lack of obstructive picture, no responsiveness to bronchodilator, and history of CLD/extreme prem, BPD is most likely.
The mother of a seven-year-old boy on maintenance chemotherapy for acute lymphoblastic leukaemia
telephones the oncology department to say that a child in her son’s class at school developed
chickenpox yesterday. Her son has no history of having had chickenpox in the past.
Which one of the following actions would you advise for her son?
A. Admission for treatment with intravenous aciclovir.
B. Immediate administration of varicella zoster immune globulin (ZIG).
C. Immediate immunisation with varicella vaccine.
D. Measurement of serum varicella antibody status and administration of ZIG if he is
seronegative.
E. Observe and treat with intravenous aciclovir if chickenpox develops.
B - immediate ZIG.
A male infant was born at term and was well at birth. At four days of age he was discharged from
hospital fully breastfed. Mild umbilical redness was noted at the discharge examination. He returned
a day later with increasing peri-umbilical redness and was commenced on antibiotics. Over the next
24 hours he developed an erythematous rash starting around the perioral area and spreading rapidly
to the face, trunk and flexural areas followed by marked bullous formation and desquamation as
shown below. He was very irritable and had a mild fever.
Which one of the following is the most likely diagnosis? A. Bullous impetigo. B. Bullous varicella. C. Epidermolysis bullosa. D. Neonatal pemphigus. E. Staphylococcal scalded skin syndrome.
E - SSSS
Caused by exotoxin-producing staphylococci. Localised infection becomes widespread after 24-48 hours. Characteristic signs are fever, skin tenderness, marked erythema, bullae, peeling of the skin. Treat with systemic antibiotics (flucloxacillin) and watch fluid balance.
A bulla is a fluid-filled sac or lesion that appears when fluid is trapped under a thin layer of your skin. It’s a type of blister.
Others
- impetigo: superficially spreading skin infection characterised by yellow-brown crust. May be bullous. Peaks late summer, common in children <5. Caused by S. aureus or GAS. Treat with oral antis.
- epidermolysis bullosa: Epidermolysis bullosa (EB) is a group of inherited diseases that are characterised by blistering lesions on the skin and mucous membranes. These may occur anywhere on the body but most commonly appear at sites of friction and minor trauma such as the feet and hands. In some subtypes, blisters may also occur on internal organs, such as the oesophagus, stomach and respiratory tract, without any apparent friction.
A foetus is found to have an isolated echogenic focus in the left ventricle on a routine 18-week
ultrasound. Which one of the following is the most likely explanation for this finding?
A. A variant of normal.
B. Down syndrome.
C. Neurofibromatosis.
D. Papillary muscle myxoma.
E. Tuberous sclerosis (rhabdomyoma).
A - variant of normal
A six-year-old boy with chronic granulomatous disease presents with a cough of three weeks duration.
A chest X-ray shows right upper lobe consolidation. A computed tomography (CT) scan of the chest
shows destruction of the right second rib.
Infection with which one of the following is most likely to give this clinical picture?
A. Aspergillus.
B. Atypical mycobacteria.
C. Candida albicans.
D. Nocardia.
E. Staphylococcus aureus.
A - aspergillus
Disorder of impaired intracellular killing of pathogens and hyperinflammatory state (e.g. IBD, granulomatous lesions). Impaired hydrogen peroxide generation and oxidative burst caused by genetic defects of phox protein subunits constituting the phagocytic NADPH oxidase.
X-linked form accounts for 2/3.
Infections:
- severe bacterial, abscesses, osteomyelitis (staph and pseudomonas)
- supperative adenitis
- pneumonia with pyogenic bacteria, nocardia, aspergillus, burkholderia
- OM
- non typhoidal salmonellosis
- BCG-osis and atypical myobacterial infections
Ix: nitroblue tetrazolium / dihydrorhodamine
Rx: prophylactic antibiotics and antifungals, steroids for granulomas
As per uptodate:
- lung infections are most common
- most common organism is aspergillus (Staph second most common)
The incidence of Grade 3 and 4 acute graft-versus-host disease is greatest when which one of the
following sources of stem cells is utilised?
A. Bone marrow from matched sibling.
B. Bone marrow from matched unrelated donor.
C. Cord blood from matched unrelated donor.
D. Peripheral blood from related matched adult donor.
E. T cell depleted bone marrow from mismatched sibling.
B - bone marrow from a matched unrelated donor
Siblings/related always better. Cord blood more compatible.
A 10-year-old girl has a history of muco-cutaneous candidiasis since age two years and
hypoparathyroidism since age four years. She now has increasing tiredness but is clinically and
biochemically euthyroid.
Which one of the following would be the most useful next test to confirm a diagnosis of adrenal
insufficiency?
A. Adrenal autoantibodies. B. C26:C22 long chain fatty acid ratio. C. Plasma adrenocorticotrophic hormone. D. Plasma cortisol. E. Plasma renin activity.
C - plasma ACTH
Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED) is an autosomal recessive disease caused by mutations in the autoimmune regulator (AIRE) gene, characterized by the clinical triad of chronic mucocutaneous candidiasis (CMC), hypoparathyroidism, and adrenal insufficiency.
MRCPCH: Autoimmune polyglandular syndrome type 1 = Addison disease, chronic mucocutaneous candidiasis, hypoparathyroidism.
In general testing for adrenal insufficiency relies on demonstrating an inability to respond when stimulated, i.e. the synacthen test. A dose of synthetic ACTH is given and cortisol measured after 30 and 60 minutes. A normal response would be a cortisol level >450-500nmol/L at 30 minutes.
An asymptomatic infant undergoing a routine discharge check on day two is noted to have a
continuous murmur. His arterial oxygen saturation is 88% in room air.
Which one of the following is the most likely diagnosis?
A. Coronary artery fistula.
B. Persistent ductus arteriosus.
C. Pulmonary atresia and ventricular septal defect.
D. Ruptured sinus of Valsalva.
E. Transposition of the great arteries.
C - PA with VSD
Cyanotic lesions: PA with VSD, TGA
Continuous murmur is from a PDA, however a PDA by itself doesn’t cause hypoxia unless there is pulmonary hypertension creating a right to left shunt, otherwise the shunt is left to right hence normal sats.
TGA - more profoundly cyanotic (sats in 50s) given separation of circuits.
Others
- coronary artery fistula: usually asymptomatic, continuous murmur, bounding pulses, not cyanotic
- rupture sinus of Valsalva: sudden onset chest pain, signs of severe heart failure and dyspnoea, continuous murmur, more common in Marfans syndrome
A four-month-old boy is referred for investigation of severe failure to thrive. His weight has
progressively fallen below the 3rd percentile (weight 3.2 kg). He drinks approximately 600 mL of
cows’ milk-based formula per day. He has only mild regurgitation after feeds and no diarrhoea.
On examination he appears generally well in himself and very alert. He has lost most of his
subcutaneous tissue. His abdomen is non-tender without palpable masses or organomegaly.
The most likely diagnosis is: A. cows’ milk intolerance. B. cystic fibrosis. C. diencephalic syndrome. D. hyperthyroidism. E. neuroblastoma.
C - diencephalic syndrome.
Uptodate
Diencephalic syndrome is a rare consequence of hypothalamic tumors and is characterized by failure to thrive with severe emaciation but normal linear growth, increased appetite, and hyperactivity.
Diencephalic syndrome, a disorder associated with central nervous system tumors, is a rare cause of profound weight loss related to increased energy expenditure but should not be overlooked.
Poor weight gain by age as per uptodate for birth-6mo:
- Poor quality of suck (whether breast- or bottle-fed) and/or oral motor dysfunction
- Improper formula preparation
- Breastfeeding problems, including insufficient milk supply
- Inadequate number of feedings
- Poor feeding interactions (eg, infant gags or vomits during feeding, caretaker misreads signals of hunger or satiety)
- Child neglect
- Parental mental illness
- Metabolic, chromosomal, or anatomic abnormalities
- Underfeeding (possibly related to poverty)
- Milk protein intolerance
- Cystic fibrosis
- Congenital heart disease
- Gastroesophageal reflux disease
Others
A - unlikely given cows milk intake with no reflux or diarrhoea
B - surely more likely than diencephalic syndrome
D - neonatal hyperthyroidism/Graves results from maternal Graves, not mentioned here
E - no palpable abdominal mass
A 10-year-old obese boy presents with high fevers, shortness of breath, and he appears quite unwell.
A chest X-ray reveals bilateral pleural effusions and a large heart. Ultrasound confirms a pericardial
effusion. There is no pulsus paradoxus. He is started on intravenous cefotaxime. He becomes more
short of breath and remains oxygen dependent after 24 hours, with his chest X-ray showing increased
pleural effusions. There are no changes in blood pressure.
The priority in his management is to:
A. add intravenous flucloxacillin.
B. insert large pleural chest drains.
C. observe in intensive care unit.
D. perform a thoracotomy to create a pericardial window.
E. perform pleural and pericardial paracentesis.
B - insert large pleural chest drains. Possibly because no tamponade/pulsus paradoxus? Otherwise would need pericardiocentesis.
Uptodate
Pulsus paradoxus: Systemic blood pressure is not constant but varies slightly from heart beat to heart beat and between inspiration and expiration. Normally, the systolic blood pressure decreases by less than 10 mmHg during inspiration, but a decline of this magnitude is not detectable on examination of the peripheral pulse. Moderate to severe cardiac tamponade, and occasionally constrictive pericarditis, induce hemodynamic changes that enhance the inspiratory fall in systolic blood pressure. This exaggerated drop in systemic blood pressure during inspiration is termed pulsus paradoxus. For patients without an indwelling arterial catheter, pulsus paradoxus must be measured by the clinician using a manually-operated sphygmomanometer. To measure pulsus paradoxus, a manually-operated sphygmomanometer is employed for blood pressure measurement in the standard fashion except that the cuff is deflated more slowly than usual. During deflation, the first Korotkoff sounds are audible with heart beats occurring only during expiration. With further cuff deflation, Korotkoff sounds become audible on all heart beats throughout the respiratory cycle. The difference between the systolic pressure at which the first Korotkoff sounds are heard during expiration and the pressure at which they are heard throughout the respiratory cycle quantifies pulsus paradoxus. Severe pulsus paradoxus, variably defined as >10 to 20 mmHg, can be palpated in the radial, brachial, or femoral pulses as a weakening or disappearance of the pulse during inspiration.
The presence of a pulsus paradoxus greater than 10 mmHg increases the likelihood of tamponade by 3.3-fold, while its absence greatly lowers but does not completely eliminate the possibility of cardiac tamponade.
The parents of a 15-year-old boy telephone about his changing behaviour over the previous two
weeks. His teachers have described poor concentration and disruptive behaviour at school and he
has been truant for most of the past week. He has been very difficult to live with, arguing with his
older brother, watching television all night and going out during the day. The parents of his girlfriend
are also concerned as they believe the boy and their daughter have started having unprotected sex
and he has encouraged her to leave school. The boy refuses to see you.
Which one of the following diagnoses best explains these symptoms?
A. Attention deficit/hyperactivity disorder.
B. Bipolar affective disorder.
C. Conduct disorder.
D. Marijuana abuse.
E. Schizophreniform disorder.
B - bipolar affective disorder. Not really sure why, can’t see anything in the stem about mania or depression. Might be outdated? 2002.
Which one of the following is the least reliable predictor of neurodevelopmental outcome in term
infants with hypoxic-ischaemic encephalopathy?
A. Age at onset of seizures of less than 12 hours.
B. An abnormal electroencephalogram (EEG) at seven days of age.
C. Anuria or oliguria for more than 24 hours.
D. Apgar score at 10 minutes.
E. Neurological examination at 10 days of age.
D - APGAR score at 10 minutes
A 15-year-old boy presents to the clinic with a three-month history of intermittent left knee pain at night
subsequent to being struck on the knee by a cricket ball which resulted in extensive bruising. One
week prior to presentation he noticed a swelling just above the knee. An X-ray of his left knee is
shown below.
Which one of the following is the most likely diagnosis? A. Aneurysmal bone cyst. B. Chronic osteomyelitis. C. Ewing sarcoma. D. Osteochondroma. E. Osteogenic sarcoma.
E - osteogenic sarcoma (AKA osteosarcoma).
Stevens-Johnson syndrome is most likely to occur with which one of the following anticonvulsant drugs? A. Carbamazepine. B. Lamotrigine. C. Phenytoin. D. Sodium valproate. E. Vigabatrin.
B - lamotrigine
Uptodate
Stevens-Johnson syndrome/toxic epidermal necrolysis — Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a severe mucocutaneous eruption that is frequently triggered by medications. Allopurinol, certain antiepileptics, antibacterial sulfonamides, and oxicam nonsteroidal anti-inflammatory drugs (NSAIDs) are most frequently implicated. This disorder is characterized by epidermal necrosis and sloughing of the mucous membranes and skin. The amount of skin detachment related to the body surface area is used to distinguish SJS from TEN; detachment affects less than 10 percent of the body surface in SJS and more than 30 percent in TEN.
An 18-month-old girl develops fever and diarrhoea. Two days later she begins to vomit, develops a
faint, generalised maculopapular rash, increasing tachypnoea and becomes obtunded. She is febrile
39.2°C, pale and poorly perfused. Her capillary refill time is 4 seconds. Her pulse is 140/minute and
thready. Blood pressure is 90/60 mmHg. Her apex beat is difficult to feel but is in the mid-axillary line.
She has a pansystolic murmur radiating to the axilla. Her respiratory rate is 52/minute and chest
clear. Her liver is palpable 5 cm below the costal margin. She is drowsy and has moderate neck
stiffness. Her generalised rash is truncal and is fine, maculopapular and blanches on pressure.
Investigations show:
haemoglobin 108 g/L [110-140]
white cell count 11.4 x 109/L [4.0-11.0]
neutrophils 5.2 x 109/L [1.0-4.0]
platelet count 201 x 109/L [150-400]
liver function tests normal
cerebrospinal fluid (CSF)
white cell count 420 x 106/L (300 polymorphs, 120 monocytes)
red cell count 20 x 106/L
sugar 2.2 mmol/L (blood sugar 4.2 mmol/L)
protein 0.5 mmol/L [0.2-0.6]
CSF Gram stain no organisms seen
chest X-ray cardiomegaly with pulmonary congestion
Which one of the following is the most likely causative organism? A. Coxsackie B virus. B. Enterovirus 71. C. Herpes simplex virus. D. Mycoplasma pneumoniae. E. Neisseria meningitidis.
A - coxsackie B virus. Given CSF results (Gram stain, protein, sugar) in keeping with viral, + heart/lung involvement, group B enteroviruses/coxsackievirus are most common cause. Enterovirus 71 causes HFM, and if involving CNS preferentially targets motor nuclei/anterior horn cells causing paresis.
Uptodate
Spectrum of disease — More than 90 percent of infections caused by the non-polio enteroviruses are asymptomatic or result only in an undifferentiated febrile illness. When more serious disease occurs, the clinical spectrum and disease severity vary with the age, gender, and immune status of the host. Some clinical syndromes (viral meningitis and some exanthema) are caused by numerous enterovirus serotypes, while others appear limited to specific enterovirus subgroups (eg, hand, foot, and mouth disease [HFM] with enterovirus A71 and some group A coxsackieviruses, and pleurodynia and myocarditis with the group B coxsackieviruses).
Central nervous system infections — Acute enterovirus infection of the CNS occurs at all ages. Meningitis is the most common CNS manifestation. Both generalized and focal encephalitis occur less frequently. Certain enteroviruses (ie, polioviruses, enterovirus D68, enterovirus A71) preferentially target the motor nuclei and anterior horn cells of the brainstem and spinal cord, causing acute paresis of cranial and spinal nerves.
Viral (aseptic) meningitis — Aseptic meningitis affects persons of all ages but is most commonly observed in infants less than one year of age. The enteroviruses cause more than 90 percent of cases in infants; the majority are due to species B enteroviruses, which include the group B coxsackieviruses and most echoviruses.
RCH - CSF interpretation
Bacterial: WCC >100 and predominantly neutrophils, usually <100 lymphocytes, protein >1, glucose CSF:blood <0.4
Viral: WCC elevated, predominantly lymphocytes, protein 0.4-1, glucose normal
Abuse of which one of the following recreational drugs during pregnancy presents the greatest risk of birth defects to the foetus? A. Amphetamines. B. Cocaine. C. Heroin. D. THC (tetrahydrocannibol). E. Tobacco.
B - cocaine. ?Outdated. Cocaine crosses the placenta and fetal blood-brain barrier; vasoconstriction is the major purported mechanism for fetal and placental damage. Teratogenic effects have not been definitively proven.
Doesn’t seem to be definitive evidence that any of the listed drugs increase the risk of birth defects.
Uptodate
THC/cannabis - Available data do not suggest an increase in congenital anomalies among children born to marijuana users.
Amphetamines - Amphetamines and their byproducts cross the placenta. No fetal structural abnormalities have been definitively associated with perinatal amphetamine exposure.
Opioids - Multiple obstetric complications have been associated with opioid use disorder in pregnancy. Nothing listed about congenital anomalies of the foetus.
Smoking - Although the overall rate of congenital malformations does not appear to be higher among infants born to pregnant individuals who smoke, smoking may increase the risk of specific anomalies. Studies have reported links between maternal smoking and the development of cleft lip with or without cleft palate, gastroschisis, anal atresia, transverse limb reduction defects, cardiac defects, digital anomalies (polydactyly, syndactyly, or adactyly), and bilateral renal agenesis or hypoplasia.
A five-year-old girl of Indian origin presents with three months of increasing lethargy and fatigue, with
occasional fevers. Previously active, she is increasingly reluctant to get up in the morning or walk,
and cries and complains that she hurts all over. A lump has appeared in her armpit and discharges
white material intermittently (see photograph shown above). The family moved from India two years
ago. She is fully immunised. There is no history of tuberculosis (TB) in the family or of TB contact.
On examination she has difficulty rising from the floor unaided and has generalised weakness most
marked in the hips and shoulders. The lesion in the axilla is firm and non-tender with induration of the
underlying skin.
Which one of the following is the most likely diagnosis?
A. Dermatomyositis.
B. Relapsing panniculitis (Weber-Christian disease).
C. Systemic lupus erythematosus.
D. Tuberculosis.
E. Visceral larva migrans.
A - dermatomyositis. Other options don’t really explain widespread weakness.
MRCPCH
Non-suppurative myositis with characteristic skin rash and vasculitis. Occurs in girls more commonly. Peak incidence 4-10 years.
Features:
- muscle pain and occasional tenderness
- muscle weakness (limb, girdle, neck, palate, swallowing)
- oedema
- rash (periorbital heliotrope eruption and oedema)
- deep red patches over extensor surface of finger joints (Gottron patches), elbows, kness, ankles
- vasculitis, skin ulceration
- nailfold and eyelid (dilated capillaries)
- retinitis in some
- myocarditis with arrhythmias can occur
- arthralgia/arthritis with contractures
- limited joint mobility
- GI dysfunction
- pulmonary involvement
- calcinosis after 1-2 years
Investigations:
- MRI shows inflammation
- ESR usually normal
- serum muscle enzymes elevated
- EMG shows denervation/myopathy
- biopsy shows inflammation or fibre necrosis and small vessel occlusive vasculitis
- ANAs positive in some
Prognosis
- variable, usually good with adequate treatment
Management
- PT, splinting
- steroids
- cytotoxic drugs if required
- anti-TNF
- careful monitoring essential
Others:
- Panniculitis refers to a group of conditions characterised by inflammation of the fat layer below the skin (sub-cutaneous fat).
- Visceral larva migrans (VLM) is a condition in humans caused by the migratory larvae of certain nematodes, humans being a dead-end host, and was first reported in 1952. Nematodes causing such zoonotic infections are Baylisascaris procyonis, Toxocara canis, Toxocara cati, and Ascaris suum.
Which one of the following is least likely to be associated with Munchausen by proxy syndrome?
A. Father frequently absent.
B. Maternal intravenous drug abuse.
C. Older sibling died from sudden infant death syndrome aged six months.
D. Recurrent polymicrobial bacteraemia.
E. Recurrent unwitnessed seizures.
B - maternal IVDU
Uptodate:
Perpetrator features — Limited evidence suggests some common features among perpetrators. Systematic study of mothers who medically abused their children have focused on perpetrators of severe abuse and found the following associations:
●Over 95 percent are female, mostly mothers or primary caretakers, although cases of collusion with other caregivers, including male members of the household have been described
●History of factitious or somatoform disorders
●History of unfortunate childhoods (eg, deprivation and abuse)
●Past history of self-harm, alcohol or drug abuse, and criminal activity
The emergence of variant Creutzfeldt-Jakob disease (vCJD) in the United Kingdom has resulted in
changes to the Australian Red Cross and New Zealand Blood Services’ procedures including a
deferral of blood donations from people who have been in the United Kingdom for six months or more
between 1980 and 1996. The main reason for this deferral is:
A. blood from a sheep incubating bovine spongiform encephalopathy (BSE) was able to cause
the disease when transfused into another sheep.
B. blood from experimentally infected primates with vCJD has been shown to transmit the
disease.
C. blood from human beings with clinically evident vCJD has been reported to transmit the
disease after intracerebral inoculation into animals.
D. there is evidence that a blood donor from the United Kingdom who was incubating vCJD has
transmitted the disease to a recipient.
E. tonsils from patients with vCJD contain the prion protein which is thought to be a good index of
infectivity.
A - blood from a sheep incubating bovine spongiform encephalopathy was able to cause the disease when transfused into another sheep.
Which one of the following sleep behaviours has the highest prevalence in primary school aged children? A. Bruxism. B. Enuresis. C. Night terrors. D. Sleep talking. E. Sleep walking.
A - bruxism
Uptodate:
Sleep-related bruxism involves activation of the masticatory muscles, resulting in tooth clenching and grinding during sleep. The prevalence of bruxism during sleep peaks in childhood and progressively declines with age. Although often asymptomatic, frequent bruxism may become clinically significant when it interferes with sleep or results in tooth wear or jaw discomfort.
Based largely on cross-sectional survey studies and self-report, sleep-related bruxism affects 15 to 40 percent of children.
RCH:
At 4 years of age, nearly 1 in 3 children wets the bed, but this falls to about 1 in 10 by age 6.
A 14-year-old girl presents with bitemporal hemianopia. Her magnetic resonance imaging (MRI) scan
is shown above. She has grown poorly for five years and has a history of polydipsia and polyuria. Her
height is <1st percentile, weight on the 3rd percentile and she has no signs of puberty.
Investigations reveal:
computed tomography (CT) scan of head mass as seen on MRI, no calcification
free thyroxine (free T4) 8 pmol/L [10-20]
thyroid-stimulating hormone (TSH) 2.50 mU/L [0.03-4.50]
urea and electrolytes normal
urine specific gravity 1.02 [1.05-1.25]
beta human chorionic gonadotrophin detected
Which one of the following is the most likely diagnosis? A. Craniopharyngioma. B. Germinoma. C. Glioma. D. Haemangioma. E. Hamartoma.
B - germinoma. Even without the image bhCG is a bit of a giveaway.
MRCPCH
Tumours derived from germ cells can be gonadal (30%) or extragonadal (70%). Extragonadal sites are the sacrococcygeal region, retroperitoneum, mediastinum, neck, and pineal area of the brain.
Gonadal tissue can give rise to any cell type, so tumours express any cell line in any stage of differentiation.
Presenting features vary with site of original. Occasionally endocrinology-related pathology with abnormal or precocious puberty.
Serum markers alpha-fetoprotein and beta-human chorionic gonadotrophin are useful in diagnosing and monitoring disease state.
You are asked to see a well neonate with a birthmark (shown above - port wine stain to face).
Which one of the following would be the most important next step in evaluation of this child?
A. Cardiac assessment.
B. Chromosomal analysis.
C. Magnetic resonance imaging (MRI) scan of the brain.
D. Ophthalmological assessment.
E. Renal ultrasound.
D - ophthalmological assessment. ?SWS -> glaucoma.
MRCPCH
Sturge Weber syndrome
- glaucoma 50% before the age of 2
- choroidal haemangiomas 40%
Uptodate:
The predominant ocular abnormality of SWS is glaucoma (increased intraocular pressure), which occurs in 30 to 70 percent of affected patients. Therefore, we suggest ophthalmology referral and follow-up for all patients presenting with SWS and for all infants and children presenting with a capillary malformation involving the upper and lower eyelids and/or extensive lesions in the frontotemporal region (V1 and V2 segments).
Sturge-Weber syndrome (SWS) is a rare congenital vascular disorder characterized by facial capillary malformation (port wine stain) and associated capillary-venous malformations affecting the brain and eye. It is not a heritable disorder. Thus, recurrence is unlikely.
SWS is characterized by a facial capillary malformation, also known as a port wine stain, and an associated leptomeningeal capillary-venous malformation (leptomeningeal angioma) involving the brain and eye. These vascular malformations are associated with specific neurologic and ocular abnormalities.
The neurologic features of SWS may be progressive and include seizures, focal neurologic deficits, and intellectual disability. Visual field defects are common when the occipital cortex is affected. These manifestations occur with variable severity. Hydrocephalus also may occur. This complication is thought to result from increased venous pressure caused by thrombosis of the deep venous channels or extensive arteriovenous anastomoses. A small proportion of patients have no neurologic abnormalities.
Ocular features of SWS include glaucoma and capillary-venous vascular malformations of the conjunctiva, episclera, choroid, and retina.
A 14-year-old girl with cystic fibrosis is reviewed in clinic. It is two months since her last review and in
that time she has lost 2 kg in weight, and has had a 10% reduction in forced expiratory volume in one
second (FEV1) but has had no recent wet cough. She has had normal stools. On examination her
chest is clear.
Which one of the following is the most likely diagnosis?
A. Diabetes mellitus.
B. Gastro-oesophageal reflux.
C. Inadequate pancreatic supplementation.
D. Inadequate salt intake.
E. Recurrent active bronchitis.
A - diabetes mellitus. Others less likely as essentially asymptomatic.
Uptodate
Cystic fibrosis-related diabetes mellitus — CFRD is a common cause of nutritional decline in individuals with CF and is also associated with declines in pulmonary function; treatment with insulin attenuates or reverses these effects. The prevalence of CFRD rises markedly with age, so that CFRD affects approximately 15 percent of adolescents with CF and almost 50 percent of adults over age 30 years. Patients with CF should be screened for CFRD using periodic oral glucose tolerance testing starting at 10 years of age.
Others
- Patients with pancreatic insufficiency characteristically have frequent, bulky, foul-smelling stools that may be oily. Older children may also report that their stools float or stick to the toilet bowl (reflecting their high fat content).
- Acute exacerbations with cough, tachypnea, dyspnea, increased sputum production, malaise, anorexia, and weight loss
- Occasionally, individuals with CF may develop subacute or chronic hypovolemia with hyponatremia, hypochloremia, hypokalemia, and metabolic alkalosis (sometimes known as pseudo-Bartter syndrome). In contrast with Bartter syndrome, urinary chloride excretion is low. This condition is caused by excessive loss of sodium and chloride in sweat and may develop in CF patients with inadequate sodium intake.
Anorexia nervosa has a highly variable outcome. Which one of the following factors is least predictive
of a poor prognosis?
A. Degree of weight loss at initial presentation.
B. Frequent hospitalisations.
C. Highly disturbed relationships with family members.
D. Prepubertal onset.
E. Poor premorbid functioning.
A - degree of weight loss at presentation
MRCPCH
Good prognosticators
- younger age at onset (?but not prepubertal…)
- less denial
- improved self-esteem
Poor prognosticators
- parental conflict
- bulimia
- coexisting behavioural disorders
A male infant is born at term following an uncomplicated pregnancy. He has Apgar scores of 8 at 1
and 5 minutes. Severe hypotonia is present from birth. Feeding is difficult to establish and tube
feeding is required. However, no respiratory support is needed. On examination at six weeks of age,
he remains very hypotonic and is still being tube fed. His reflexes are normal and despite his
hypotonia, he is observed to move all limbs and has a normal cry.
The investigation which is most likely to make a diagnosis in this infant is:
A. acetylcholine receptor studies.
B. deletion studies for spinal muscular atrophy.
C. dystrophin deletion studies.
D. fluorescent in-situ hybridisation (FISH) for deletion on chromosome 15p.
E. mutation testing for myotonic dystrophy.
D - FISH for deletion on chromosome 15p
?Prader Willi Syndrome
MRCPCH
Hypotonia in neonates:
- Central causes: encephalopathy, IVH, infection, T21/13/18, structural brain abnormalities, metabolic disease, drugs, PWS, hypothyroidism, kernicterus (early)
- Spinal cord lesions: trauma, tumours, cysts, vascular malformations
- NMD: SMA, congenital myotonic dystrophy, congenital myopathies, myasthenia gravis
PWS
- clinical: neonatal hypotonia and poor feeding
- moderate learning disability
- hyperphagia and obesity later in childhood
- small genitalia
- 70% deletion on paternal chromosome 15
A 13-year-old girl presents with a four-week history of progressive deterioration with lethargy,
occasional vomiting and peripheral oedema. Urinalysis shows 4+ blood and 4+ protein.
The following blood results are obtained:
haemoglobin 78 g/L [115-150]
plasma potassium 7.0 mmol/L [3.5-5.0]
plasma creatinine 0.60 mmol/L [0.04-0.08]
plasma urea 60.0 mmol/L [3.2-7.7]
Her renal biopsy (shown below) shows crescentic glomerulonephritis.
Her clinical progress over the next three months is most likely to show which one of the following?
A. Complete and spontaneous recovery of renal function.
B. Dialysis dependence.
C. Good response to high dose cyclosporin A.
D. Persistent heavy proteinuria.
E. Recurrent macroscopic haematuria.
D - persistent heavy proteinuria
Rapidly progressive GN — Rapidly progressive glomerulonephritis (RPGN) is a clinical syndrome manifested by features of subacute nephritic syndrome with a progressive loss of kidney function over a comparatively short period of time (days, weeks, or months). It is characterized morphologically by extensive crescent formation.
RPGN occurs rarely in children. Causes of pediatric RPGN include:
●Primary GN – IgA nephropathy, MPGN, and anti-glomerular basement membrane (GBM) disease
●Secondary GN – Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis, lupus nephritis, poststreptococcal GN, IgAV (HSP) nephritis
Early diagnosis with kidney biopsy and serologic testing, and early initiation of appropriate therapy are essential to minimize the degree of irreversible kidney injury. Empiric therapy may be started in patients with severe disease, particularly if either kidney biopsy or interpretation of the biopsy will be delayed. However, despite aggressive treatment, approximately half of the affected children will develop end-stage kidney disease (ESKD).
