Microcephaly is a type of neurodevelopmental disorder of children characterized by smaller head size as compared to other children of the same age and gender. In many cases, it occurs due to abnormal development of brain during fetal growth.
A smaller than normal head size is the classical symptom of microcephaly. Many children often have a normal head size at birth; but eventually as the child grows, the size of the head appears to become proportionately smaller compared to the rest of the body.
Some percentages of affected children also are dwarf and underweight. In addition, development of other motor functions is delayed and neurological defects are evident. Seizures and convulsions are a common accompaniment of microcephlay. Some children with microcephaly may develop clumsiness while some other may develop spastic qualdriplegia. Affected children develop a large head with a preceding forehead and a wrinkled scalp .
Entire Body System
- Developmental Disorder
Microcephaly (MCPH) is a developmental disorder characterized by reduced brain size and intellectual disability. A proportion of microcephaly is caused by defects in a single gene. [ncbi.nlm.nih.gov]
The consequences of microcephaly itself include neurologic and developmental disorders (eg, seizure disorders, intellectual disability, spasticity). [msdmanuals.com]
- El Salvador
Locally acquired Zika was reported for the first time in Brazil in May 2015, and the virus has since been reported in 14 countries and territories in Latin America and the Caribbean: Brazil, Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras [cdc.gov]
These women traveled to American Samoa, Brazil, El Salvador, Guatemala, Haiti, Honduras, Mexico, Puerto Rico and Samoa. All of the countries have reported local transmission of the Zika virus. [newsweek.com]
FILE - Women wait their turn for their pre-natal exams at the National Hospital for Women in San Salvador, El Salvador, Jan. 29, 2016. [voanews.com]
As of January 27, 2016, the list of affected countries includes Barbados, Bolivia, Brazil, Colombia, Dominican Republic, Ecuador, El Salvador, French Guiana, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto [livescience.com]
- Cape Verde
Virgin Islands, Venezuela, Samoa and Cape Verde, according to the Centers for Disease Control (CDC). [livescience.com]
The locations are: Barbados, Bolivia, Ecuador, Guadeloupe, Saint Martin, Guyana, Cape Verde, and Samoa. [arstechnica.co.uk]
Studies of Zika-infected pregnant Latin American women who were due to deliver their babies soon should yield evidence, Kieny said, adding that data also was coming from studies in French Polynesia and Cape Verde. [reuters.com]
- Common Cold
If it was Zika, there was the unimaginable potential that microcephaly could become as widespread as the common cold. Aedes aegypti is in every city in every part of Brazil, and for 30 years the country had tried—and failed—to control the pest. [newsweek.com]
- Failure to Thrive
Failure to thrive and mild facial dysmorphic features were also present. To our knowledge, this complex malformation (neurocutaneous) phenotype has not been previously reported. [ncbi.nlm.nih.gov]
‘However, three or more minor malformations, especially if associated with short stature or failure to thrive, microcephaly or developmental delay, should engender further investigation.’ [en.oxforddictionaries.com]
Among them may be present: failure to thrive, spasticity (involuntary muscle contractions), impaired motor function, mental and psychomotor retardation, seizures, sight loss and hearing problems, joint and skeleton deformities (including dwarfism – short [medigoo.com]
Then, they reversed course, saying that the severity of her microcephaly was stronger than they had initially imagined, and she was showing a failure to thrive. They told Gwen she should get ready to say goodbye to her precious girl. [redbookmag.com]
After birth, a baby with microcephaly may have these signs and symptoms: Small head size Failure to thrive (slow weight gain and growth) High-pitched crying Little appetite or problems with feeding Muscle spasms To diagnose microcephaly after birth, your [marchofdimes.org]
- Skin Rash
After the first reports of Zika symptoms (skin rash, fever, arthralgia, headache, and conjunctivitis) were reported, a subsequent increase was reported in cases of Guillain-Barre syndrome and microcephaly [ 5, 6 ]. [link.springer.com]
The maternal infection with Zika virus was considered in the presence of symptoms (skin rash, fever associated with arthralgia, myalgia, non-purulent conjunctivitis or headache) and positive result of the transcription polymerase chain reaction (RT- PCR [nutritionj.biomedcentral.com]
MCPH1 607117 primary microcephaly 1 AR 23 MED17 603810 postnatal progressive microcephaly, seizures, and brain atrophy AR 1 MFSD2A 614397 Microcephaly 15, primary, autosomal recessive AR 1 MSMO1 607545 Microcephaly, congenital cataract, and psoriasiform dermatitis [centogene.com]
- Small Head
Additional tests used to diagnose microcephaly might include: Measuring the circumference of your child’s head. Measuring the circumference of the parents’ heads to determine if small head size runs in the family. CT scan of the head. [gillettechildrens.org]
Health Minister Marcelo Castro said Wednesday, March 9, that the Brazilian Health Ministry has changed guidelines that determine if newborns have microcephaly, or abnormally small heads that can indicate brain damage. [dailymail.co.uk]
Microcephaly is an abnormally small head. Often the head is small because the brain is small and abnormally developed. Microcephaly can be caused by many disorders including genetic abnormalities, infections, and brain defects. [msdmanuals.com]
"Relative" microcephaly, i.e., a small head on a small child, may be associated with a much better intellectual prognosis than absolute microcephaly, although the average IQ of children with absolute microcephaly ascertained in a normal school system [ncbi.nlm.nih.gov]
Reaction to microcephaly "There is huge fear of microcephaly. It's all over the local news about the Zika virus case in Texas. People are afraid as the virus can be passed by mosquitoes - we have a lot of mosquitoes here in Texas. [bbc.com]
There may be thousands of these children in Brazil, and scientists fear thousands more might come as the Zika virus leaps across Latin America and the Caribbean. [nytimes.com]
However, abortion activists have been exploiting the crisis, causing fears among pregnant women and calling for legalized abortion in South America, where abortion is widely prohibited. [lifenews.com]
The fear of being right quarreled in Brito’s mind with the fear of being wrong. If it was Zika, there was the unimaginable potential that microcephaly could become as widespread as the common cold. [newsweek.com]
This is why we can and should turn our attention not to fear-mongering but to help creating places where children with disabilities can thrive. Edmund taught me that disability is not hell on earth for a family. It’s not constant misery. [thedailybeast.com]
This classification could be confusing in rare disorders with variable phenotypic characteristics. However, identification of the causative gene through genetic study would allow determining the definite diagnosis. [ncbi.nlm.nih.gov]
The confusion has lead Brazil’s public health leaders to ask that health workers temporarily halt reporting suspected cases so they can mull the data. [dallasnews.com]
Brazil's microcephaly figures are causing no end of confusion. [nature.com]
Regardless of the confusion, Zip became Barnum’s most consistent draw and due to that position Zip became one of the better paid performers – $100 a week in addition to that $1 a day ‘hush money’. [web.archive.org]
At birth, if microcephaly is suspected, then a thorough checkup should be carried out. In addition, the head circumference should be measured and compared with standardized growth charts. In many cases, the head circumference of the parents can also be measured to determine whether the condition is a common occurrence in the family. Parents should be asked about the developmental milestones of the child to further understand the condition.
If there are signs of developmental delay, certain tests along with Computerized Tomography (CT) scan and Magnetic Resonance Imaging (MRI) of the head will be required to determine the underlying disease conditions .
In many cases, it is possible to detect microcephaly by prenatal ultrasound examination carried out during the third trimester. However, the condition can be difficult to diagnose in the early stages of fetal development .
- So far there is no treatment regime to enlarge the child’s head. If craniosynostosis is the underlying cause of microcephaly, then surgery can be done to correct the fusion and provide space for development of child’s brain. However, in other conditions, only supportive therapy is indicated to manage the symptoms and improve the child's quality of life.
- Medications are given in cases when the child is hyperactive or is experiencing seizures and convulsions. In addition, various types of therapies such as speech, occupational and physical are also employed in the early developmental years.
- If microcephaly is diagnosed at birth, then frequent examinations are required in order to monitor the brain development of the child. The child’s family is also given education about the disease which is helpful in improving the child's quality of life.
Microcephaly cannot be treated. The treatment regime that is administered is supportive in nature, primarily geared towards improving the quality of life of the affected children. The life expectancy of children with microcephaly is greatly reduced and the chances of having a normal brain function are poor.
Abnormal development of the brain during infancy or fetal growth can lead to a head size that is smaller than normal. In many cases, microcephaly occus as a result of genetic factors. Other factors which can also favor abnormal brain development include the following:
- Craniosynostosis, which causes premature fusion of sutures leading to abnormal brain growth
- Cerebral anoxia, that causes decreased oxygen supply to the brain during fetal growth
- Chromosomal abnormalities such as Down syndrome
- Infections during pregnancy and exposure of the fetus to drugs or alcohol and toxicogenic compounds
- Development of phenylketonuria and severe malnutrition during pregnancy 
The average prevalence of microcephaly is estimated to be 25%. The condition of microcephaly can also lead to intellect disability; however, in about 15% cases, the child has normal intellectual levels . In a study carried out on children affected by microcephaly, it was found that 10.5% of them had IQ scores below 70; whereas, 28% of them had IQ scores 70 – 80. In the US, about 25,000 infants annually develop microcephaly .
The growth of the head depends on the brain development. When the brain cannot grow at a normal rate, microcephaly develops. Various genes and genetic defects have a pivotal role to play in the development of microcephaly. Studies have postulated the fact that mutation occurring in the DNA repair pathway is one of the major causes of poor brain growth. In addition to genetic mutations, centrosomal abnormalities are another factor that favor the development of microcephaly .
It is not always possible to prevent the development of microcephaly. However, parents with affected children may want to consider genetic counseling for future pregnancies .
In addition to this, pregnant mothers can take certain steps to avoid exposing the fetus to alcohol, drugs, toxins and other chemical compounds. Pregnant women are also advised to consume a nutritious diet to avoid malnutrition because severe malnutrition has been identified as a potential risk factor for poor brain development during fetal growth .
Children affected with microcephaly have to face serious developmental problems and deteriorated quality of life. So far, there is no treatment for correcting this condition; however, if supportive therapies are introduced in the early stages; the quality of life of the affected children can be improved. Interplay of various genetic and environmental factors is known to play a role in the causation of microcephaly .
Microcephaly is a condition in which the head of a child is smaller than normal for his age. It is frequently accompanied by underlying disorders of the brain and mental retardation. It usually results from genetic abnormalities. Exposure of the fetus to toxins, alcohol and chemicals during pregnancy also causes poor brain growth and contributes to the development of microcephaly. Symptoms of microcephaly include seizures, convulsions, high pitched crying, mental retardation and developmental delays. The diagnosis of microcephaly is made by measuring the head circumference of the affected child. Thereafter, several tests to determine the growth of the child are done at various stages of growing years. There is no specific treatment for microcephaly. Medications are given for managing the symptoms of seizures, convulsions and hyperactivity. Speech and occupational therapy are also indicated to improve the quality of life.
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