Abnormal Child Development + normal/ abnormal growth Flashcards
A 2-year-old child has delays in speech, motor skills, and social interaction. What is the most appropriate term for this pattern of development?
Global developmental delay
A baby is not reaching for objects by 6 months. What is this considered?
Red flag
A child with previously normal development begins losing speech and purposeful hand use. What’s the most likely cause?
Rett syndrome
= Characteristic developmental regression, especially in girls
Which of the following is a prenatal cause of global developmental delay?
A) Hypoxic-ischaemic encephalopathy
B) PKU
C) Meningitis
D) Prematurity
PKU
= It’s a metabolic prenatal cause; A and D are perinatal, C is postnatal
A 4-year-old boy has delayed walking but normal language and social development. What’s this pattern?
Specific delay
Only motor domain affected → think of causes like Duchenne or CP
A child is diagnosed with developmental delay. What’s the first-line genetic investigation?
Oligoarray CGH
Gold standard test for Autism Spectrum Disorder
Autism Diagnostic Observation Schedule
What’s a key feature that distinguishes developmental delay from developmental deviation?
Delay = slower but typical pattern; Deviation = abnormal pattern (e.g. autism)
What measurement should always be plotted in developmental assessment?
Height, weight, and head circumference
A child has motor delay and calf pseudohypertrophy. What test do you order?
Creatine kinase — to screen for Duchenne muscular dystrophy
What is specific Developmental Delay?
Only one domain is affected
(eg) only motor, or only speech/language
Example: A child who has normal play, learning and behaviour but isn’t talking by age 2
Think: Isolated problem, rest of development normal
What is Global Developmental Delay (GDD)?
Two or more domains delayed before age five
(eg) speech + motor, or cognition + social
Example: A child who isn’t walking at 20 months and isn’t speaking at all
Think: Widespread delay in skills
What is Developmental Regression?
Loss of previously acquired skills
Example: A child who used to talk and play normally but stops talking and loses interest in people
Think: They had the skill, but now it’s gone
What is Developmental Deviation?
Atypical development, not just slow
Example: A child who shows repetitive behaviours and doesn’t engage socially (eg, autism)
Think: Unusual pathway, not just behind
If development odd or uneven?
Deviation
When to use oligoarray CGH (comparative genomic hybridisation)?
🧪 First-line test for unexplained developmental delay, intellectual disability, congenital anomalies
Detects microdeletions and duplications (much smaller than karyotyping)
Can’t detect balanced translocations or single-gene disorders
✅ Use when
= child has global delay, dysmorphic features, or unexplained birth defects
When to use Karyotyping?
🧬 Low-resolution chromosome analysis
Detects large chromosomal abnormalities (eg, trisomy 21, Turner’s, translocations)
Slower and less sensitive than CGH
✅ Use when
= you suspect known syndromes with visible changes (e.g. Down’s, balanced translocations in the family)
When to use Whole genome sequencing (WGS)?
📚 Sequences all DNA, including coding and non-coding regions
Can detect single-gene mutations, CNVs, and more
Still used more in research or specialist genetics settings
✅ Use when
= CGH, karyotype, and other tests are normal, but clinical suspicion remains high
When to use FISH (fluorescence in situ hybridisation)?
🔍 Targeted test for a specific microdeletion or rearrangement
Fast and used when you already have a clinical suspicion (eg, DiGeorge, Williams)
✅ Use when
= looking for a known condition, not a screening test
What are the prenatal causes of global developmental delay?
- Down’s syndrome
- PKU, hypothyroidism
- neuronal migration disorders
- TORCH infections
- TOXINS
At what age is pubertal delay diagnosed in boys?
14
What is used as the first-line investigation for a girl with short stature and delayed puberty?
Karyotyping - always rule out Turner’s syndrome
A 6-year-old girl develops breast buds and pubic hair. What is this?
true central precocious puberty if <8 in girls
Which measurement tool is used to assess length in a 1-year-old?
children under 2 should be measured lying down
What is short stature defined as?
Below 2nd centile or >2SD below MPH
A 4-year-old child is growing along the 9th centile consistently. What does this indicate?
Normal growth
Pubertal delay is the absence of secondary sexual development in a girl at what age?
13
What is the best method to calculate a child’s expected height range based on parental height?
mid-parental height helps estimate genetic potential
A boy has short stature, delayed puberty, and a normal bone age. What’s the most likely diagnosis?
Constitutional growth delay
What is the most common error when plotting on a growth chart?
age errors
What defines a fall in growth that is concerning?
more than 2 centile spaces is significant
A 13-year-old girl has not started breast development. What is this?
Pubertal delay
What is a key marker of pubertal onset in girls?
breast buds = first sign of puberty
‘Developing early, pubic hair/breast/testes before age 8–9, tall for age’
What does this describe?
Precocious puberty
‘Girl, short, with dysmorphic features, high FSH’
What is this describing?
Turner’s syndrome
45X
‘Short, but healthy otherwise, delayed bone age, family history’
What does this describe?
Constitutional growth delay
= most common cause of short stature
‘Growing slowly, below 2nd centile, delayed puberty, low IGF-1’
This suggests what?
Growth hormone deficiency
Precocious puberty is seen in boys and girls at what age?
Girls = <8
Boys = <9
Referral points?
- doesn’t smile at 10 weeks
- cannot sit unsupported at 12 months
- cannot walk at 18 months
What are the fine motor skill problems?
hand preference before 12 months is abnormal and may indicate cerebral palsy
What are the gross motor problems?
Duchenne muscular dystrophy
What is an isolated delay in speech?
A speech delay without motor or social issues
Example: No words by 18 months, but normal motor skills
What is an isolated delay in gross motor skills?
A delay in large movements (e.g., walking, sitting) with normal speech and fine motor
Example: Not walking by 18 months, but normal speech
What is an isolated delay in fine motor skills?
A delay in hand movements (e.g., grasping, pointing) with normal speech and gross motor
Example: Can’t pick up small objects at 12 months, but can walk and talk
A 4-month-old baby girl is brought to the clinic by her dad, who is concerned about her development and growth. She has three older siblings who have all developed and grown appropriately. She was born at term via normal vaginal delivery. Her 5-day blood spot test was normal.
The parents have noticed that the baby seems “floppy” and is unable to hold her head up at an age when her other siblings could. She makes no effort to reach for toys and seems uninterested in following objects with his gaze. The parents could be convinced that she occasionally smiles but does not coo or vocalise
What investigations would be most useful in identifying the cause of this child’s symptoms?
Genetic Karyotyping
Social (Personal-Social) Delay
- No smiling by 6–8 weeks
- Doesn’t engage in play or respond to name by 12 months
- Not showing interest in others for 2 years
Vision Delay
- No eye contact or social smile by 6–8 weeks
- Doesn’t follow objects visually by 3 months
- Bumping into objects or not reaching accurately
Hearing and Speech Delay
- No babbling by 6 months
- No single words by 12–15 months
- Not following simple instructions by 18 months
- No 2-word phrases by 2.5 years
Fine Motor Delay
- Can’t reach or grasp toys by 6 months
- No pincer grip by 12 months
- Struggles to stack blocks or use crayons by 2 years
Gross Motor Delay
- Not rolling by 6 months
- Not sitting without support for 8 months
- Not walking by 18 months
