1. An approach to a child with
microcephaly
Dr.Anita Lamichhane
MD Resident (paediatrics)
Shaikh Zayed Hospital
Lahore

2. Microcephaly
A child whose head circumference is more than
three standard deviations below the mean for
age and sex

3.  Normal head circumference at birth
 Male: 35cm(mean) range = 32---37 cm
 Female: 34cm(mean)
 Rate of growth of head circumference
 2cm/month 1st three months of life
 1cm/month 4-6 months of age
 0.5cm/month 6-12 months of age
 47cm at 1 yr of age
 49 cm at 2 yrs of age

6.  HC reflects brain volume, a small skull reflects a small brain.
 Incidence of moderate to severe mental retardation
 HC from 2-3 SD below the age is 33%.
 HC > 3 SD, incidence is 62%
 Not always associated with mental retardation

7. types of microcephaly
 Primary microcephaly  Secondary microcephaly (non
(genetic) genetic /acquired)
primary defect in brain
development
 prenatal onset
 prenatal onset
 postnatal onset
 postnatal onset

8. Causes of microcephaly

9. Primary microcephaly ( genetic)
 Prenatal onset
chromosomal anomalies
 Down syndrome (21 trisomy)
 Edward syndrome (18 trisomy
 Patau syndrome (13 trisomy )
malformations
 Holoprosencephaly
 Lissencephaly

10. Contd.
malformation syndrome
 de Lange syndrome
hereditary conditions
 Autosomal recessive ( familial)
 Autosomal dominant

11.  Post natal onset
malformation Syndromes
 Aicardi syndrome
 Angel man syndrome
 Fanconi syndrome
 Rubinstein Taybi syndrome

12. Contd…
 Prader-willi syndrome
 Beckwith wiedemann syndrome
 Bloom syndrome
 Cri-du-chat ( 5P )

13. Secondary microcephaly (nongenetic
/acquired)
 Prenatal onset
 Intrauterine TORCH infection
 Fetal alcohol syndrome
 Maternal phenylketonuria

14. Contd…
 Post natal onset
 perinatal asphyxia with resultant HIE
 perinatally acquired herpes simplex
encephalitis/meningitis
 head injury
 endocrine anomalies
hypothyroidism
hypopitutarism
 inherited metabolic disease such as PKU

15.  Congenital CNS anomalies
 Agenesis of the cerebellar vermis
 Agenesis of the corpus callosum
 Encephalocele
 Macrogyria
 Porencephaly
 Schizencephaly

16. Others…..
 Hyperthermia
 Radiation
 Malnutrition
 Drugs
Fetal hydantoin syndrome

17. pathogenesis
 Occurs as a result of
Small brain & poorly growing skull
An abnormal neuronal migration during fetal
development.
Cytoarchitectural derangements.
heterotopias of neuronal cells.

18. Microcephaly Vera
 an Autosomal recessive disorder
 severe hypoplasia of the frontal regions of the brain and skull.
 severe mental retardation.
Note: HC alone should never be used to establish a prognosis for
intellectual development.

19. Aicardi Syndrome
 females only  Severe mental &
development retardation
 agenesis of the corpus
callosum  seizures
 infantile Spasms  gray matter heterotopias.

20. Bloom Syndrome
 Autosomal recessive  a butterfly shaped facial rash.
 Microcephaly  prone to develop Cancer.
 short stature  Genetic diagnosis is available.
 DNA fragility

21. Down's Syndrome
 Trisomy 21  small low set ears and
 Microcephaly.
 incurving of the fifth finger.
 a single palmar crease ( simian
 up slanting Fissures, crease)
 epicanthal Folds,  hypotonia
 flat facial profile,

22. A child with Down Syndrome

23. Edward syndrome
 Trisomy 18
 Microcephaly
 Prominent occiput
 Micrognathia
 Narrow forehead
 Cleft lip and palate
 Low set ears
 ASD & VSD

24. Cri-Du-Chat Syndrome
 Microcephaly
 shrill cat like cry
 High arch palate
 small chin

25. Rubinstein taybi syndrome
 Mental & growth retardation
 Broad thumbs with talpism
 Microcephaly with
 mandibular & maxillary
hypoplasia
 anteverted nose &
 antemongoloid slant to
palpebral fissures

26. Cornelia de Lange syndrome
 Mental & growth retardation
 Synophrys
 Micrognathia
 ASD & VSD

27. Patau syndrome
 Trisomy 13
 Microcephaly
 Cutis aplasia ( scalp defect )
 Eyes

cataract
 Colobomata
 Microphthalmia
 corneal opacities
 Hands
polydactyly

28. Phenylketonuria
 Deficiency of phenylalanine hydroxylase in the liver
 Accumulation of phenylalanine in the blood
 Toxic to brain
 Causes
microcephaly
mental retardation
cerebral palsy
eczema
mousy odor of urine

29. Contd…
 Diagnosed by increased serum phenylalanine in
Blood
 Guthrie test ( 5th– 15th day of life)
 Treatment A diet low in phenylalanine

30. How to approach a child
with microcephaly

31. History
 Family history (for genetic cause)
 Exposure of radiation during pregnancy
 Maternal drug history
 Infection during pregnancy
 Maternal DM or PKU

32. Contd..
 Difficult delivery:
forceps delivery,
 meconium stained liquor
 cord around the neck
 and low Apgar Scores all raises the possibility of hypoxic ischemic
encephalopathy
 Significant fever during neonatal period

33.  h/o
 high-pitched cry
 poor feeding
 seizures
 increased movement of the arms
and legs (spasticity)

34. Examination
 Introduction of oneself to the parents
 Size of the parents & other siblings head circumference
 Note the child’s alertness
 Look for any Dysmorphic feature
( intrauterine TORCH, de Lange,
Rubinstein Taybi)

35.  Child’s posture & symmetry of the movements
( voluntary & involuntary )
 Inspect the skin for neurocutaneous stigmata
 Head circumference
 Height & weight & plot in the centile chart

36.  Note the child’s overall growth
generally small
only head small
 examine the head for any scar marks
( surgical repair of Craniosynostosis,
closure of Encephalocele)

37. Contd..
 Shape of the head
 flat occiput of Autosomal recessive
microcephaly
 Palpate the head for ridging along the suture line & any deformity of
skull contour
 (Craniosynostosis) or bony defects ( repaired
Encephalocele)

39.  Anterior fontanelle
 a large AF occurs in
 trisomies
 congenital rubella
 hypothyroidism
 Petechiae or skin rash

40.  Eye
 micropthalmos (TORCH)
 lens for cataract (TORCH, trisomies )
 fundus for chorioretinitis (TORCH)
 glaucoma ( congenital rubella )
 red reflex ( rubella)

41. hypotelorism
(Holoprosencephaly)
upward slant
( down syndrome)
epicanthi fold
( trisomies )
squint
( TORCH)
pupils for anisocoria
( cong. Varicella )

42.  Ears for hearing
impairment ( TORCH )
 neck for goiter
hypothyroidism

43.  Systemic examination
CVS
 for congenital heart defects ( congenital rubella,trisomies )
Abdomen
 hepatosplenomegaly (TORCH)
Genitalia
 micropenis with hypopitutarism structure ( cryptorchidism)
Joint contractures
 Asses the gross and fine motor development– 180 degree maneuver

44. Investigations
 Serological tests for intrauterine TORCH infection
 Chromosomal analysis for Autosomal Trisomy syndrome
 Neonatal screening tests for PKU & congenital hypothyroidism

45.  Urine test
Metabolic screening to detect virus
excretion with CMV
 CSF
to detect intrauterine or perinatal TORCH
infection

46. a) Skull x ray
 for cerebral calcification
CMV --- periventricular
Toxoplasmosis—diffuse
 to detect early closure of sutures

47. CT SCAN/ MRI
 for cerebral malformations
 evidence of perinatal asphyxia or
intrauterine infection

48.  Genetic studies are indicated in patients
with Dysmorphic features

49.  Microcephaly may be diagnosed before birth
by prenatal ultrasound.
 Genetic counseling should be done

50. Management
 No treatment for microcephaly
 Baby’s head cannot be returned to a normal size & shape
 Includes focusing on preventing or minimizing deformities &
maximizing the child’s capabilities at home & in the community.

51. Contd..
 According to the cause.
 Anticonvulsants
 Physiotherapy
 Hearing & speech therapy
 Dietary management for failure to
thrive
 Genetic counseling