Pediatric Testing 3rd year 2nd semester Flashcards
What is the first step in evaluating infantile growth hormone deficiency?
A) MRI of the brain
B) Random serum GH level
C) Serum IGF-1 level
D) Growth hormone stimulation test
✅ C) IGF-1 is a more stable marker of GH secretion and is the first step in screening.
❌ A) MRI is used later if GHD is confirmed, to check for pituitary abnormalities.
❌ B) Random GH levels are not useful due to pulsatile secretion.
❌ D) Stimulation tests are done if IGF-1 is low but not as a first step.
Which of the following statements about Small for Gestational Age (SGA) and Intrauterine Growth Restriction (IUGR) is true?
A) All SGA infants have IUGR
B) Preterm SGA infants always exhibit catch-up growth
C) Some SGA children remain short throughout life
D) Skeletal maturation is always delayed in SGA infants
Correct Answer: C) Some SGA children remain short throughout life
✅ C) While many SGA infants exhibit catch-up growth, about 15-20% remain permanently short.
❌ A) Not all SGA infants have IUGR—some are constitutionally small without an abnormal restriction of growth.
❌ B) Preterm infants often have inadequate catch-up growth due to poor postnatal nutrition.
❌ D) Skeletal maturation is usually normal and corresponds to chronological age in SGA children.
Which of the following is NOT a diagnostic criterion for ADHD according to the DSM-5?
A) Symptoms must be present before age 12
B) Symptoms must cause impairment in academic or social functioning
C) Symptoms must be observed in at least one setting
D) Symptoms must include at least 6 or more for children under 17
✅ Answer: C) Symptoms must be observed in at least one setting
🔹 Explanation: ADHD symptoms must be observed in two or more settings (e.g., school, home, social settings). If symptoms appear in only one setting, other factors like environment or stress might be causing them.
Explanation:
✅ A) Correct – ADHD symptoms must appear before age 12 for a diagnosis.
✅ B) Correct – ADHD must impair academic, social, or daily functioning (otherwise, it may just be high energy or inattention).
❌ C) Incorrect – ADHD symptoms must be observed in at least two settings (e.g., home and school). If symptoms are only present in one setting, environmental factors may be at play.
✅ D) Correct – Children under 17 need 6+ symptoms, while adults (17+) need only 5 symptoms.
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Clinical Presentation & Diagnosis
* 9-10% of children
* Triad of symptoms
- Inattention
- Hyperactivity
- impulsivity
* DSM-5 describes 3 categories
- Hyperactive-impulsive
- Inattentive
- Combined
1. Must have 6 or more symptoms
2. Symptoms present in 2 or more settings
3. Symptoms cause impairment in academic or social functioning
4. Symptoms present prior to age 12
* A diagnosis of ADHD is allowed in children with ASD
* Symptoms thresholds are lower for 17+: only 5 symptoms are required
Which subtype of ADHD is more commonly diagnosed in girls?
A) Hyperactive-impulsive
B) Inattentive
C) Combined
D) Oppositional
✅ Answer: B) Inattentive
✅ B) Correct – Girls more often have the inattentive subtype, which can lead to underdiagnosis.
Explanation:
❌ A) Incorrect – Hyperactive-impulsive ADHD is more common in boys.
❌ C) Incorrect – The combined subtype is equally common in boys and girls.
❌ D) Incorrect – Oppositional Defiant Disorder (ODD) is not a subtype of ADHD but can be a comorbidity.
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ADHD Management
* Based on the CPS
- Treatment is individualized and depends on comorbidities: anxiety,
sleep disorders, learning disabilities
- Behavioural modification
1. Structure and consistency in daily routine
2. Positive reinforcement
- Educational interventions: academic impairment is a big feature
1. Preferential seating in classroom
2. Positive behaviour reinforcement
3. Consistent structure
4. Repetition of information
5. Instruction includes visual and auditory modalities
- Social skills training
1. Counselling for poor self esteem, oppositional behaviour,
conduct problems
Which of the following conditions is NOT commonly associated with ADHD?
A) Fragile X syndrome
B) Fetal Alcohol Syndrome
C) Cystic Fibrosis
D) Turner Syndrome - ( is a Chromosomal variation where a person is born with a 45X chromosome pattern rather than the typical 46XX
Turner syndrome, commonly known as 45,X, or 45,X0, is a chromosomal disorder in which female cells have only one X chromosome instead of two, or are partially missing an X chromosome leading to the complete or partial deletion of the pseudoautosomal regions in the affected X chromosome.
✅ Answer: C) Cystic Fibrosis
❌ C) Incorrect – Cystic Fibrosis is a lung disorder that does not affect ADHD risk.
Explanation:
✅ A) Correct – Fragile X syndrome is a genetic disorder that often coexists with ADHD.
✅ B) Correct – Fetal Alcohol Syndrome affects brain development, leading to ADHD-like symptoms.
✅ D) Correct – Turner syndrome (a chromosomal disorder) has been linked to ADHD symptoms.
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* Prevalence of inattentive subtype higher in girls
* Prevalence of hyperactivity subtype higher in boys
* Etiology, Risk Factors & Differential Diagnosis
- Associated with other psychiatric conditions
1. Mood disorder, conduct disorder, oppositional defiant disorder, Tourette syndrome or tics, learning disabilities, anxiety
- Associated with a variety of genetic disorders
1. Fragile x syndrome, Williams syndrome, Angelman syndrome, XXY (Klinefelter syndrome), Turner syndrome
- Associated with other circumstances
1. Fetal alcohol syndrome, CNS trauma, CNS infections,
prematurity, metabolic conditions, obstructive sleep apnea
At what age do early signs of Autism Spectrum Disorder (ASD) typically appear?
A) At birth
B) 6 months
C) 12-18 months
D) 5 years
✅ Answer: C) 12-18 months; Atypical communication and interaction appear between 12-18 months
Explanation:
❌ A) Incorrect – Autism is not usually detectable at birth.
❌ B) Incorrect – By 6 months, symptoms are usually not apparent..
❌ D) Incorrect – Most children are diagnosed around 3-4 years, but symptoms appear earlier.
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ASD
* Features are present prior to 3 yoa, some not visible unless triggered by social demands
- Not diagnosed until 3-4 yoa
* Symptoms cause clinically significant impairment in function
* Management
- Atypical communication/interaction observed 12-18mo
1. Failure to orient one’s name, regard people directly, use gestures, develop speech
i) Lack of pointing, showing, imitating, sharing, playing with toys as they are intended, joint attention with parent not there
Which of the following is an appropriate screening tool for ASD in toddlers?
A) PHQ-9
B) M-CHAT-R/F
C) MoCA
D) Beck Depression Inventory
✅ Answer: B) M-CHAT-R/F is a standard autism screening tool for 16-30 months.
Explanation:
❌ A) Incorrect – PHQ-9 is for depression screening.
❌ C) Incorrect – MoCA is a cognitive test for adults.
❌ D) Incorrect – Beck Depression Inventory is not for ASD.
A child with ASD shows regression in speech and social skills at 18 months. What should be done next?
A) Start behavioral therapy immediately
B) Refer to a neurologist to rule out electrical status epilepticus of sleep
C) Recommend speech therapy only
D) Wait until age 5 before further evaluation
✅ Answer: B) Refer to a neurologist to rule out electrical status epilepticus of sleep
Regression may indicate epileptic disorders, requiring EEG testing.
Explanation:
❌ A) Incorrect – Behavioral therapy is helpful but neurological evaluation is critical.
❌ C) Incorrect – Speech therapy alone does not address underlying causes.
❌ D) Incorrect – Waiting may worsen the child’s outcomes.
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ASD Management
- Based on history: evaluate metabolic disorders, lead levels, thyroid studies
- Neuroimaging if microcephaly/macrocephaly is present
- Refer to neurologist if there is skill regression 12-24 mo
- 20-30% have plateau or loss of skills (language and/or social) between 12-24 mo; loss is gradual
1. Refer to neurologist, rule out electrical status epilepticus of sleep (also has regression)
Interpretation of the Note:
“Refer to neurologist, rule out electrical status epilepticus of sleep (also has regression)”
This means the patient should be referred to a neurologist to rule out (R/O) electrical status epilepticus during sleep (ESES) as a potential diagnosis.
ESES is a rare epilepsy syndrome where abnormal electrical brain activity occurs predominantly during sleep and can lead to cognitive, language, and behavioral regression in children.
The mention of “regression” suggests that the patient has been losing previously acquired skills (e.g., speech, motor function, or academic abilities), which raises concern for neurological conditions like ESES.
- Recurrence risk
1. 4-14% if there is already 1 child with ASD
What is the most effective early intervention for ASD?
A) Special diets (e.g., gluten-free)
B) Early intensive behavioral therapy
C) Pharmacologic treatment
D) Reducing screen time
✅ Answer: B) Early intensive behavioral therapy; Early, intensive behavioral therapy (≥25 hrs/week) improves long-term outcomes.
Explanation:
❌ A) Incorrect – Diet changes have no proven effect on ASD symptoms.
❌ C) Incorrect – Medications help with comorbid conditions (e.g., anxiety) but do not treat ASD itself.
❌ D) Incorrect – Reducing screen time is beneficial but not a primary treatment.
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ASD Interventions
- Behavioural: early intervention: 25 hours per week for optimal cognitive and adaptive function
1. Cost: $1.4-2.4 million
- Initiation prior to age 3 = better outcomes
- Repetitive behavours that are calming and enjoyable should not be targeted for treatment
- Early Start Denver Model as an example
- Address concerns on sleep, feeding, constipation, pain from an
infection, anxiety
- Focus on sleep hygiene
- Pharmacologic approach: address inattentiveness, hyperactivity, anxiety, irritability, aggression
1. Stimulants less likely to be effective, resulting in discontinuation
2. Consider non stimulants like guanfacine for kids <5yoa, those with lower IQ, severe anxiety, unstable mood, low weight/poor appetite
- Functional behaviour assessment
- Positive behaviour reinforcement
1. Replacement behaviours for negative behaviours
Family & Social Support - Importance of family centered care
- Education on symptoms and treatment strategies for behaviour but also for comorbid conditions
- Importance of community resources and support networks
- Advocate for educational resources
Which of the following features is commonly associated with Turner Syndrome?
A) Tall stature
B) Webbed neck
C) Macroglossia
D) Hypotonia
Answer: B) Webbed neck – Correct. One of the characteristic physical traits of Turner Syndrome is a webbed neck, often due to lymphedema in infancy.
A) Tall stature – Incorrect. Turner Syndrome is associated with short stature, not tall stature (which is more common in Marfan Syndrome).
C) Macroglossia – Incorrect. Macroglossia (large tongue) is a feature of conditions like Beckwith-Wiedemann Syndrome, not Turner Syndrome.
D) Hypotonia – Incorrect. Hypotonia (low muscle tone) is more commonly seen in Down Syndrome rather than Turner Syndrome.
Which organ system is most commonly affected in Turner Syndrome?
A) Cardiovascular
B) Gastrointestinal
C) Respiratory
D) Musculoskeletal
Answer: A) Cardiovascular – Correct. Turner Syndrome is associated with congenital heart defects, including coarctation of the aorta and bicuspid aortic valve.
B) Gastrointestinal – Incorrect. While Turner Syndrome can have some GI-related concerns (e.g., celiac disease), it is not the primary system affected.
C) Respiratory – Incorrect. Unlike conditions such as cystic fibrosis or Marfan Syndrome (which can cause spontaneous pneumothorax), Turner Syndrome does not primarily affect the respiratory system.
D) Musculoskeletal – Incorrect. While short stature is a characteristic feature, musculoskeletal complications are not the main concern.
What is a common endocrine issue in individuals with Turner Syndrome?
A) Hyperthyroidism
B) Hypogonadism
C) Hyperparathyroidism
D) Cushing’s syndrome
B) Hypogonadism – Correct. Ovarian failure is common in Turner Syndrome, leading to primary hypogonadism and infertility.
A) Hyperthyroidism – Incorrect. Turner Syndrome is associated with hypothyroidism, not hyperthyroidism.
C) Hyperparathyroidism – Incorrect. This condition is more commonly associated with parathyroid tumors or multiple endocrine neoplasia.
D) Cushing’s syndrome – Incorrect. Cushing’s syndrome is caused by excessive cortisol production and is unrelated to Turner Syndrome.
Which of the following is a potential treatment or management strategy for Turner Syndrome?
A) Growth hormone therapy
B) Testosterone replacement
C) Gene therapy
D) Bone marrow transplant
A) Growth hormone therapy – Correct. Growth hormone therapy is commonly used to improve final adult height in Turner Syndrome patients.
B) Testosterone replacement – Incorrect. Turner Syndrome affects females and typically requires estrogen therapy, not testosterone.
C) Gene therapy – Incorrect. There is no current gene therapy available to correct the chromosomal abnormality in Turner Syndrome.
D) Bone marrow transplant – Incorrect. This treatment is used for hematologic conditions like leukemia but is not relevant for Turner Syndrome.
What is the most common chromosomal abnormality leading to Down Syndrome?
A) Trisomy 18
B) Monosomy X
C) Trisomy 21
D) XXY Syndrome
Answer: C) Trisomy 21 because Down Syndrome occurs due to three copies of chromosome 21.
A is incorrect because Trisomy 18 causes Edwards Syndrome, not Down Syndrome.
B is incorrect because Monosomy X is Turner Syndrome.
D is incorrect because XXY Syndrome is Klinefelter Syndrome, which affects males.
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Trisomy 21 Down Syndrome
- Occurs in 1:700 newborns
- Three copies of chromosome # 21, instead of the normal 2
1. Impairment in nondisjunction: failure of a pair of chromosomes
to separate during meiosis
- Individuals have recognizable features, congenital anomalies and increased infant and neonatal mortality
- Living children have cognitive and physical disabilities/challenges
- Most trisomic embryos are lost early in pregnancy
1. Early screening in pregnancy: increased anxiety and burden of deciding whether or not to terminate the pregnancy; on the flip side: gives more time to create development support plans, and treatment plans when baby is born
Which of the following health concerns is most commonly associated with Down Syndrome?
A) Marfan Syndrome
B) Congenital heart disease
C) Huntington’s disease
D) Sickle cell anemia
Answer: B) Congenital heart disease; because up to 50% of individuals with Down Syndrome have congenital heart defects.
A is incorrect because Marfan Syndrome is a connective tissue disorder.
C is incorrect because Huntington’s disease is a neurodegenerative disorder unrelated to Down Syndrome.
D is incorrect because sickle cell anemia is a genetic blood disorder unrelated to Down Syndrome.
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Trisomy 21 Down Syndrome
- Distinct facial features and generalized hypotonia
1. Upslanting palpebral fissures, flat nasal bridge, epicanthal folds, midface hypoplasia, flattened occiput
- Newborn: feeding difficulties, constipation, prolonged physiologic jaundice, transient blood count abnormalities
- Childhood: thyroid dysfunction, visual issues, hearing loss, obstructive sleep apnea, celiac disease, atlantooccipital instability
- Cognitive disability is variable: mild to severe
- Complications: up to 50% have congenital heart disease, septal defects, esophageal and duodenal atresias seen in about 15% of kids
- Increased incidence of: transient myeloproliferative disorder, leukemia, Alzheimer disease
Trisomy 21 Down Syndrome
- Treatment
1. Surgical intervention for cardiac and GI anomalies
2. Developmental support: feeding, physical and occupational therapy, speech therapy, screening for hearing loss and autoimmune disorders (hypothyroidism and celiac)
3. Goal: help children develop to their full potential
4. Parental support: support groups National Down Syndrome Society www.ndss.org
5. Genetic Counselling: risk of have infants with trisomies increases with maternal age, most parents have normal chromosomes, some parents have abnormal karyotypes and so risk is greater
Duchenne Muscular Dystrophy is caused by a mutation in which gene?
A) FBN1
B) Dystrophin
C) CFTR
D) BRCA1
Answer: B) Dystrophin because DMD is due to a mutation in the dystrophin gene, which leads to progressive muscle degeneration.
A is incorrect because FBN1 is associated with Marfan Syndrome.
C is incorrect because CFTR mutations cause Cystic Fibrosis.
D is incorrect because BRCA1 mutations are linked to breast and ovarian cancer.
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Duchenne Muscular Dystrophy
- X-linked disorder
- Gene on the X chromosome responsible for the synthesis of
the muscle cytoskeleton protein dystrophin
1. Mutation causes synthesis failure = progressive degeneration of skeletal and cardiac muscle
2. Large deletions or duplications detected in 65% of cases
3. Molecular analysis has replaced muscle biopsy for diagnosis
- Incidence in Canada: 1/4700 live male births
- Considered with these symptoms: hypotonia, proximal muscle weakness, pseudohypertrophy of calf muscles by age 5-6. delayed motor milestones or abnormal gait
1. Elevated creatinine kinase
How does dystrophin deficiency lead to Duchenne Muscular Dystrophy (DMD)?
Dystrophin is a structural protein that helps anchor muscle fibers to the surrounding extracellular matrix, providing stability during muscle contraction. It connects the actin cytoskeleton of muscle cells to the dystroglycan complex in the cell membrane, which links to the extracellular matrix.
In DMD, mutations in the dystrophin gene (DMD gene) result in little or no production of functional dystrophin.
Without dystrophin, muscle fibers become fragile and susceptible to damage during contractions.
Over time, muscle cells undergo repeated injury and necrosis, leading to progressive muscle wasting and weakness.
The body attempts to repair the damage, but fibrous and fatty tissue replaces muscle fibers (pseudohypertrophy), further impairing function.
Which of the following is NOT a characteristic of Duchenne Muscular Dystrophy?
A) Progressive muscle weakness
B) X-linked inheritance
C) Increased risk of cardiomyopathy
D) Autosomal recessive inheritance
Answer: D) Autosomal recessive inheritance
D is correct because DMD follows an X-linked recessive inheritance pattern, not autosomal recessive.
A is incorrect because progressive muscle weakness is a hallmark of DMD.
B is incorrect because DMD is inherited in an X-linked manner.
C is incorrect because cardiomyopathy is a common complication in individuals with DMD.
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X-linked Inheritance vs. Autosomal Recessive Inheritance
X-linked inheritance (like DMD):
The gene responsible is located on the X chromosome.
Males (XY) who inherit a mutated X chromosome always express the disease because they have no second X chromosome to compensate.
Females (XX) can be carriers (one normal X and one mutated X), and may have mild symptoms but usually don’t develop full-blown disease.
Autosomal recessive inheritance (e.g., cystic fibrosis, sickle cell anemia):
The gene responsible is on one of the 22 autosomes (non-sex chromosomes).
A person must inherit two copies of the mutated gene (one from each parent) to develop the disease.
If they inherit only one mutated copy, they are a carrier but do not usually have symptoms.
Marfan Syndrome primarily affects which type of tissue?
A) Epithelial tissue
B) Connective tissue
C) Nervous tissue
D) Muscular tissue
Answer: B) Connective tissue because Marfan Syndrome is a connective tissue disorder caused by a mutation in the FBN1 gene.
A is incorrect because epithelial tissue is not the primary issue in Marfan Syndrome.
C is incorrect because it is not a nervous system disorder.
D is incorrect because although the disorder affects musculoskeletal structures, the primary defect is in connective tissue.
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Marfan Syndrome
* Autosomal dominant disorder
- 75% of individuals have an affected parents, 25% have a de novo mutation in the FBN1 gene
* Skeletal abnormalities: arachnodactyly based on Ghent criteria
- Tall thin with long limbs, long thin facies, deep set eyes, malar flattening, retrognathia
- Motor milestones delayed
* Lens dislocation
* Dilation of the aortic root
- Spontaneous pneumothorax, dysrhythmias, aneurism and dissection
* Dural ectasia
* Positive family history in some cases
What does FBN1 stand for?
FBN1 stands for Fibrillin-1, which is a glycoprotein essential for the formation of elastic fibers in connective tissue.
It is encoded by the FBN1 gene on chromosome 15.
Mutations in FBN1 cause Marfan Syndrome, leading to weakened connective tissue and complications in the cardiovascular, skeletal, and ocular systems.
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Why is the most serious complication of Marfan Syndrome aortic dissection and not mitral valve prolapse?
You’re absolutely right that Marfan Syndrome affects connective tissue, and mitral valve prolapse (MVP) is a possible consequence. However, aortic dissection is far more life-threatening than MVP, which is why it was the correct answer.
Here’s why:
Aortic dissection occurs when a tear forms in the inner layer of the aortic wall, allowing blood to enter and separate the layers.
This is a medical emergency because it can lead to aortic rupture, severe internal bleeding, and death.
In Marfan Syndrome, aortic root dilation (weakening and enlargement of the aortic base) predisposes individuals to dissection.
In contrast, while mitral valve prolapse (MVP) is common in Marfan Syndrome, it is rarely life-threatening.
MVP occurs when the mitral valve flaps bulge backward into the left atrium, sometimes causing mitral regurgitation (leakage of blood backward).
Severe regurgitation may eventually require valve repair or replacement, but it does not pose an immediate fatal risk like aortic dissection.
So, while both MVP and aortic complications are part of Marfan Syndrome, aortic dissection is the most severe and urgent cardiovascular risk.
Which of the following is a serious cardiovascular complication of Marfan Syndrome?
A) Aortic dissection
B) Myocardial infarction
C) Mitral valve prolapse
D) Ventricular hypertrophy
Answer: A) Aortic dissection because Marfan Syndrome is associated with aortic root dilation, which increases the risk of aortic dissection.
B is incorrect because myocardial infarction is more commonly linked to atherosclerosis.
C is incorrect because while mitral valve prolapse may occur, it is not the most serious cardiovascular complication.
D is incorrect because ventricular hypertrophy is more associated with hypertension and other cardiac conditions.
Which of the following is an important differential diagnosis to consider when evaluating a patient with suspected Marfan Syndrome?
A) Ehlers-Danlos Syndrome
B) Homocystinuria
C) Loeys-Dietz Syndrome
D) All of the above
Answer: D) All of the above
Explanation:
A is correct because Ehlers-Danlos Syndrome is another connective tissue disorder that can present with joint hypermobility and vascular complications.
B is correct because homocystinuria can have overlapping features with Marfan Syndrome, but it requires metabolic testing for differentiation.
C is correct because Loeys-Dietz Syndrome also involves aortic aneurysms and dissection but presents with distinct craniofacial features.
D is correct because all of the listed conditions must be considered in the differential diagnosis of Marfan Syndrome.
Which of the following treatments can slow the rate of aortic dilation in patients with Marfan Syndrome?
A) Beta-adrenergic blockers
B) Angiotensin II receptor antagonists
C) Diuretics
D) Both A and B
Answer: D) Both A and B
Explanation:
A is correct because beta-adrenergic blockers reduce stress on the aorta, decreasing the risk of dilation and dissection.
B is correct because angiotensin II receptor antagonists (ARBs), like losartan, have been shown to slow aortic dilation in Marfan Syndrome.
C is incorrect because diuretics do not specifically slow aortic dilation and could lower blood pressure excessively, potentially leading to hypoperfusion.
D is correct because both A and B are evidence-based treatments for Marfan-related aortic dilation.
