Microcephaly

Microcephaly

Dr. Noorjan A.Muhammed

Microcephaly

Is a neurodevelopmental disorder.
It is usually defined as a head circumference (HC) more than 2 standard deviations below the mean for age and gender
or
(HC) less than 5th centile for age and gender. Microcephaly may be congenital or it may develop in the first few years of life.

Causes

It has been classified in two types based on the onset:
A. Congenital

1.Familial microcephaly

2.Chromosomal Syndromes
Down syndrome
Edward Syndrome
Patau Syndrome
Cri-du-chat
Williams syndrome
DiGeorge syndrome

3. Congenital Infections

Congenital cytomegalovirus infection
Toxoplasmosis
Congenital rubella syndrome

4. Drugs

Fetal alcohol syndrome


5. Other

Radiation exposure to mother

Maternal Malnutrition
Maternal Phenylketonuria
Poorly controlled Gestational diabetes
Maternal Hypothyroidism
Placental insufficiency

B.Postnatal causes

1. Inborn errors of metabolism
Mitochondrial disorders
Amino acidopathies
Organic acidemia

2. Disruptive injuries

Traumatic brain injury
Hypoxic-ischemic encephalopathy
Ischemic stroke
Hemorrhagic stroke


3. Infections
Congenital HIV encephalopathy
Meningitis
Encephalitis

4. Toxins

Lead poisoning
Chronic renal failure

5.Others

Hypothyroidism
Anemia
Congenital heart disease
Malnutrition

Presentation

Infants with microcephaly are born with either a normal or reduced head size. Subsequently the head fails to grow while the face continues to develop at a normal rate, producing a child with a small head and a receding forehead, and a loose, often wrinkled scalp.

Development of motor functions and speech may be delayed.

Hyperactivity and intellectual disability are common occurrences
Convulsions may also occur.
Motor ability varies, ranging from clumsiness in some to spastic quadriplegia in others.


Prognosis

Generally there is no specific treatment for microcephaly.

Treatment is symptomatic and supportive.