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Ailmemts & Remedies Pediatric

Heart Murmurs in Babies

Definition
The heart has four separate chambers, and four one-way valves attaching them. The two lower chambers pump, and they’re called ventricles. The two upper chambers accept incoming blood, and they’re called atria.

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Blood that’s low in oxygen comes from the body into the right atrium, then goes through a valve into the right ventricle, and over to the lungs to get more oxygen. That oxygen-rich blood returns to the heart through the left atrium, then across a valve into the left ventricle. From there it’s pumped through the aorta, which is a large blood vessel, and on to smaller blood vessels throughout the body.

A heart murmur is the term used when an extra swishing sound is heard besides the normal heartbeat, which is the sound of the valves opening and closing. A doctor can hear these sounds with a stethoscope, but a child needs to sit very quietly for that to happen, because his heart is near his chest wall, and outside sounds can get picked up. You might be asked to hold your baby in your lap while the doctor listens, or calm him down; if he’s crying, it’s almost impossible to hear a murmur.

Parents often panic when they are told their baby has been diagnosed with a heart murmur, yet do not realize that heart murmurs are actually common in babies and that, in general, they resolve themselves without affecting the baby’s overall health.Murmurs are very common during childhood and the vast majority are not a sign of disease or anything to worry about. It is extremely important for parents to understand which type of murmur their child has been diagnosed with, if it requires further evaluation and treatment options available if the result is a serious heart defect.

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Symptoms:
There may be no other symptoms – a murmur is generally diagnosed by the sound heard through the stethoscope.

These murmurs usually get resolved by the time the child become adult. The defective heart murmur may need to be tested to find out the real cause of it. The child with innocent murmur can live as healthy life as any other child of healthy heart. Pathological heart murmurs is a defect in the heart with a hole which may be there in the two chambers of the heart. The chest pain, rapid heart beat, bluish color or fingertips, shortness of breath, fainting, fatigue with exertion and signs of congestive heart failure are some of serious symptoms of this disease.

However, if the murmur is due to disease – ie, it isn’t harmless or ‘innocent’ – the child may be cyanosed (blue, especially around the lips), short of breath (especially on feeding), off their feeds, failing to thrive (poor growth) or have frequent chest infections.

Causes:
The majority of heart murmurs are the result of the fast rate at which children’s hearts beat or normal variations in the structure of the heart. Some factors, such as fever or excitement, make these innocent murmurs more likely because they increase the speed at which the heart pumps.

The common cause of baby’s heart murmur is congenital heart disease which may occur when blood vessels or valves attached to the heart don’t get developed even before the child is born. Some children may get birth with heart defects. One in hundred children may be found with this type of birth disorder.

. Some serious heart defects may be due to some illnesses like rheumatic fever, heart disease, heart attacks. It is due to heart defects in structural disorder of a baby’s heart. The defects may be of valve abnormalities, cardiomyopathy and septal which produce murmur. Cardiomyopathy is usually a heart disorder of muscle which can result in defective functioning of the heart.

However, a heart murmur is also the most common sign of congenital heart defects caused by abnormal development of the heart tissues. This may be atrial or ventricular septal defects – a hole in the heart or an abnormal hole between two heart chambers. Sometimes the connections between vessels from the heart don’t close after birth as they should, resulting in patent ductus arteriosus.

Other abnormalities of the heart valves and still rarer problems can also cause a murmur.

Heart murmurs may also be caused by heart failure and infection involving the heart.

Diagnosis:
Although parents often fear the worse, not all heart murmurs are serious. They’re graded on scale from 1 to 6, where 1 is almost inaudible and 6 is quite loud. When your baby’s doctor hears it, he’ll note where in the heart it occurs, at what point in the heartbeat cycle, what type of sound it makes, and whether the noise changes when your child moves. If further evaluation is required, your child will be referred to a pediatric cardiologist.

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Sometimes a heart murmur will be heard at one appointment, when it wasn’t noticed at the last one. This could be because heart murmurs are better heard when children are in certain positions or have a different heart rate. It could also mean it’s due to a heart problem that’s recently developed, or one that’s been there since birth but hasn’t been severe enough to make a detectable murmur.

It can be difficult to tell an innocent murmur from a suspicious one. If a child has an unusual murmur but seems well, the doctor may suggest the child comes back for review in a few weeks or months.

Tests including a chest x-ray, electrocardiogram and echocardiogram may be recommended to examine the structure of the heart and check for abnormalities. If heart disease is suspected, more extensive tests may be needed.

Treatment :
The treatment of innocent murmur is not required at all. Congenital heart defects may be diagnosed after conducting laboratory tests. The parents should consult pediatric cardiologist after confirming the tests. The doctor will provide the suitable treatment to regulate the proper blood flow to the heart.

Some medications may solve the problem but in case of severity, the surgery can be conducted to treat the ailment. The mitral valve prolapsed may not require any treatment but only periodic checkups can be sufficient to be conducted. The doctor can prescribe some anti-biotic but medications should never be self prescribed which pose some serious problems.

The surgery may be conducted in serious types of cases. The anti-clotting medication, medications to put control on irregular heartbeat, palpitations and to open the blood vessels

Alternative treatment:
If a heart murmur requires surgical treatment, there are no alternative treatments, although there are alternative therapies that are helpful for pre- and post-surgical support of the patient. If the heart murmur is innocent, heart activity can be supported using the herb hawthorn (Crataegus laevigata or C. oxyacantha) or coenzyme Q10. These remedies improve heart contractility and the heart’s ability to use oxygen. If the murmur is valvular in origin, herbs that act like antibiotics as well as options that build resistance to infection in the valve areas may be considered.

Prognosis
Most children with innocent heart murmurs grow out of them by the time they reach adulthood. Severe causes of heart murmurs may progress to severe symptoms and death.

Prevention:
Heart murmurs in infants or babies can not be prevented but the blood pressure may be treated before the heart murmur gets developed. It is also advised to prevent rheumatic fever in the children to prevent heart murmurs. The regular check ups may be conducted to get to know the defects in advance to treat the ailment.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Sources:
http://www.ehow.com/about_5280475_heart-murmur-babies.html
http://health.stateuniversity.com/pages/696/Heart-Murmurs.html
http://www.livestrong.com/article/22104-heart-murmur-babies/
http://www.bbc.co.uk/health/physical_health/conditions/in_depth/heart/heartmurmurs2.shtml

Heart Murmur in Infants or Newborn Babies

http://fromyourdoctor.com/topic.do?title=Heart+How+it+Works&t=7986

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Ailmemts & Remedies Pediatric

Tetralogy of Fallot

Definition:
Tetralogy of Fallot (TOF) is an abnormality of the heart and major blood vessels, which may be found in babies.

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It’s one of the most complex heart problems, as there are four different abnormalities (hence the term ‘tetralogy’):

•A large ventricular septal defect – one of the more serious types of hole in the heart, in which there is a connection between the two main pumping chambers of the heart (ventricles)

•Narrowing of the pulmonary valve (pulmonary stenosis) – this means the heart has to work harder to pump blood into the lungs to collect oxygen

•Right ventricular hypertrophy – thickening of the muscle wall of the right ventricle

•A displaced aorta – the major blood vessel that takes blood out of the heart and directs it around the body

Although these are the main problems, every child is different and there may be all sorts of other abnormalities.

Tetralogy of Fallot occurs in approximately 400 per million live births.

It was described in 1672 by Niels Stensen, in 1773 by Edward Sandifort, and in 1888 by the French physician Étienne-Louis Arthur Fallot, for whom it is named.

Symptoms:
Tetralogy of Fallot symptoms vary, depending on the extent of obstruction of blood flow out of the right ventricle and into the lungs. Signs and symptoms may include:

click to see the pictures

You may click to see different pictures of  Tetralogy of Fallot

*A bluish coloration of the skin caused by blood low in oxygen (cyanosis)

*Shortness of breath and rapid breathing, especially during feeding

*Loss of consciousness (fainting)

*Clubbing of fingers and toes — an abnormal, rounded shape of the nail bed

*Poor weight gain

*Tiring easily during play

*Irritability

*Prolonged crying

*A heart murmur

Tet spells
Sometimes, babies with tetralogy of Fallot will suddenly develop deep blue skin, nails and lips after crying, feeding, having a bowel movement, or kicking his or her legs upon awakening. These episodes are called “Tet spells” and are caused by a rapid drop in the amount of oxygen in the blood. Toddlers or older children may instinctively squat when they are short of breath. Squatting increases blood flow to the lungs. Tet spells are more common in young infants, around 2 to 4 months old.

Seek medical help if you notice that your baby has the following symptoms:

*Difficulty breathing

*Bluish discoloration of the skin

*Passing out or seizures

*Weakness

*Unusual irritability

If your baby becomes blue (cyanotic), immediately place your child on his or her side and pull the knees up to the chest. This helps increase blood flow to the lungs.

Causes:
The cause of TOF isn’t fully understood. While a baby is in the womb, something interferes with the development of the heart and major blood vessels.

Its cause is thought to be due to environmental or genetic factors or a combination. It is associated with chromosome 22 deletions and DiGeorge syndrome.

Specific genetic associations include:

JAG1[4]
NKX2-5[5]
ZFPM2[6]
VEGF[7]
It occurs slightly more often in males than in females.

Embryology studies show that it is a result of anterior malalignment of the aorticopulmonary septum, resulting in the clinical combination of a VSD, pulmonary stenosis, and an overriding aorta. Right ventricular hypertrophy results from this combination, which causes resistance to blood flow from the right ventricle.

Although no specific single genetic abnormality has yet been found to explain every case, genetics often do play a part in these types of malformations (known as conotruncal abnormalities). In some children, a particular genetic problem can be identified, such as DiGeorge syndrome, where a small piece of chromosome 22 is lost or deleted.

Some researchers have suggested that TOF is caused by an autosomal recessive gene that has yet to be identified and which has variable penetrance (that is, it doesn’t always cause disease).

However, this is far from proven and TOF has also been linked to environmental factors such as certain medications or alcohol taken by the mother while pregnant.

Whatever the cause, in those families who have a child with TOF, the risk of a second child being born with the condition is only increased very slightly.

Risk factors:-
While the exact cause of tetralogy of Fallot is unknown, several factors may increase the risk of a baby being born with this condition. These include:

*A viral illness in the mother, such as rubella (German measles), during pregnancy

*Maternal alcoholism

*Poor nutrition

*A mother older than 40

*A parent with tetralogy of Fallot

*Babies who are also born with Down syndrome or DiGeorge syndrome

Diagnosis:-
The abnormal “coeur-en-sabot” (boot-like) appearance of a heart with tetralogy of Fallot is easily visible via chest x-ray, and before more sophisticated techniques became available, this was the definitive method of diagnosis. Congenital heart defects are now diagnosed with echocardiography, which is quick, involves no radiation, is very specific, and can be done prenatally.

Treatment:-
Emergency management of tet spells:

Prior to corrective surgery, children with tetralogy of Fallot may be prone to consequential acute hypoxia (tet spells), characterized by sudden cyanosis and syncope. These may be treated with beta-blockers such as propranolol, but acute episodes may require rapid intervention with morphine to reduce ventilatory drive and a vasopressor such as epinephrine, phenylephrine, or norepinephrine to increase blood pressure. Oxygen is effective in treating spells because it is a potent pulmonary vasodilator and systemic vasoconstrictor. This allows more blood flow to the lungs. There are also simple procedures such as squatting and the knee chest position which increases aortic wave reflection, increasing pressure on the left side of the heart, decreasing the right to left shunt thus decreasing the amount of deoxygenated blood entering the systemic circulation.

Palliative surgery:
The condition was initially thought untreatable until surgeon Alfred Blalock, cardiologist Helen B. Taussig, and lab assistant Vivien Thomas at Johns Hopkins University developed a palliative surgical procedure, which involved forming an anastomosis between the subclavian artery and the pulmonary artery (See movie “Something the Lord Made”).  It was actually Helen Taussig who convinced Alfred Blalock that the shunt was going to work. This redirected a large portion of the partially oxygenated blood leaving the heart for the body into the lungs, increasing flow through the pulmonary circuit, and greatly relieving symptoms in patients. The first Blalock-Thomas-Taussig shunt surgery was performed on 15-month old Eileen Saxon on November 29, 1944 with dramatic results.

The Potts shunt  and the Waterston-Cooley shunt  are other shunt procedures which were developed for the same purpose. These are no longer used.

Currently, Blalock-Thomas-Taussig shunts are not normally performed on infants with TOF except for severe variants such as TOF with pulmonary atresia (pseudotruncus arteriosus).

Total surgical repair:
The Blalock-Thomas-Taussig procedure, initially the only surgical treatment available for Tetralogy of Fallot, was palliative but not curative. The first total repair of Tetralogy of Fallot was done by a team led by C. Walton Lillehei at the University of Minnesota in 1954 on a 11-year-old boy. Total repair on infants has had success from 1981, with research indicating that it has a comparatively low mortality rate.

Total repair of Tetralogy of Fallot initially carried a high mortality risk. This risk has gone down steadily over the years. Surgery is now often carried out in infants one year of age or younger with less than 5% perioperative mortality. The open-heart surgery is designed (1) to relieve the right ventricular outflow tract stenosis by careful resection of muscle and (2) to repair the VSD with a Gore-Tex patch or a homograft. Additional reparative or reconstructive surgery may be done on patients as required by their particular cardiac anatomy

Prognosis:-
Untreated, Tetralogy of Fallot rapidly results in progressive right ventricular hypertrophy due to the increased resistance on the right ventricle. This progresses to heart failure (dilated cardiomyopathy) which begins in the right heart and often leads to left heart failure. Actuarial survival for untreated Tetralogy of Fallot is approximately 75% after the first year of life, 60% by four years, 30% by ten years, and 5% by forty years.

Patients who have undergone total surgical repair of Tetralogy of Fallot have improved hemodynamics and often have good to excellent cardiac function after the operation with some to no exercise intolerance (New York Heart Association Class I-II). Surgical success and long-term outcome greatly depends on the particular anatomy of the patient and the surgeon’s skill and experience with this type of repair.

Ninety percent of patients with total repair as infants develop a progressively leaky pulmonary valve as the heart grows to its adult size but the valve does not. Patients also may have damage to the electrical system of the heart from surgical incisions if the middle cardiac nerve is accidentally tapped during surgery. If the nerve is touched, it will cause abnormalities as detected by EKG and/or arrhythmias.

Long-term follow up studies show that patients with total repair of TOF are at risk for sudden cardiac death and for heart failure. Therefore, lifetime follow-up care by an adult congenital cardiologist is recommended to monitor these risks and to recommend treatment, such as interventional procedures or re-operation, if it becomes necessary.

The use of antibiotics is no longer required by cardiologists and varies from case to case.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://www.bbc.co.uk/health/physical_health/conditions/fallotstetralogy.shtml
http://en.wikipedia.org/wiki/Tetralogy_of_Fallot
http://www.drattawarsandeep.com/tetralogy_of_fallot.php
http://www.mayoclinic.com/health/tetralogy-of-fallot/DS00615/DSECTION

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News on Health & Science

Folic Acid Food Cuts Birth Defects

Fortifying flour and pasta products with folic acid appears to cut the number of babies born with congenital heart disease, the most common   of all birth defects, Canadian researchers said on Tuesday.

While food fortification is not mandatory in Europe, a 1998 Canadian requirement has led to a 6 percent drop each year in the number of such defects in Quebec, they reported in the British Medical Journal.

“These findings support the hypothesis that folic acid has a preventive effect on heart defects,” Louise Pilote of McGill University in Montreal and colleagues wrote. “Public health measures to increase folic acid intake were followed by a decrease in the birth prevalence of severe congenital heart defects.”

…………………..

Currently 67 countries fortify wheat flour, 47 of them by mandate, Helena Gardiner of Imperial College in London and Jean-Claude Fouron of CHU Sainte-Justine University Hospital Centre in Montreal noted in an editorial. Folic acid helps the body make healthy new cells.

It is important that women get enough of it before and during a pregnancy to prevent major birth defects involving a baby’s brain or spine. Leafy green vegetables, fruits, dried beans peas and nuts contain folic acid. It can be added to grain products or taken as a dietary supplement.

Even with fortification, many women do not get enough folic acid. In their study, Pilote and colleagues identified all infants born in Quebec with severe congenital heart defects between 1990 and 2005.

Their analysis showed no change in how many babies were born with severe heart defects in the nine years before fortification. But there was a 6 percent decrease annually for each of the seven years after fortification began.

The dip may seem modest but given the complex treatment for the often fatal heart defects, even a small reduction can significantly reduce costs health care costs, the researchers said.


Sources
:The Times Of India

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Diagnonistic Test

Echocardiogram

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Definition
An echocardiogram uses sound waves to produce images of your heart. This common test allows your doctor to see how your heart is beating and pumping blood. Your doctor can use the images from an echocardiogram to identify various abnormalities in the heart muscle and valves.

CLICK TO SEE

It determines the size of your heart, and assess how well it is functioning. The test can estimate how forcefully your heart is pumping blood, and can spot areas of the heart wall that have been injured by a previous heart attack or some other cause.

Depending on what information your doctor needs, you may have one of several types of echocardiograms. Each type of echocardiogram has very few risks involved.

Why it’s done
Your doctor may suggest an echocardiogram if he or she suspects problems with the valves or chambers of your heart or your heart’s ability to pump. An echocardiogram can also be used to detect congenital heart defects in unborn babies.

Depending on what information your doctor needs, you may have one of the following kinds of echocardiograms:

*Transthoracic echocardiogram. This is a standard, noninvasive echocardiogram. A technician (sonographer) spreads gel on your chest and then presses a device known as a transducer firmly against your skin, aiming an ultrasound beam through your chest to your heart. The transducer records the sound wave echoes your heart produces. A computer converts the echoes into moving images on a monitor. If your lungs or ribs obscure the view, a small amount of intravenous dye may be used to improve the images.

*Transesophageal echocardiogram. If it’s difficult to get a clear picture of your heart with a standard echocardiogram, your doctor may recommend a transesophageal echocardiogram. In this procedure, a flexible tube containing a transducer is guided down your throat and into your esophagus, which connects your mouth to your stomach. From there, the transducer can obtain more detailed images of your heart.

*Doppler echocardiogram. When sound waves bounce off blood cells moving through your heart and blood vessels, they change pitch. These changes (Doppler signals) can help your doctor measure the speed and direction of the blood flow in your heart. Doppler techniques are used in most transthoracic and transesophageal echocardiograms.

*Stress echocardiogram. Some heart problems — particularly those involving the coronary arteries that feed your heart muscle — occur only during physical activity. For a stress echocardiogram, ultrasound images of your heart are taken before and immediately after walking on a treadmill or riding a stationary bike. If you’re unable to exercise, you may get an injection of a medication to make your heart work as hard as if you were exercising.

Risk Factors:
There are minimal risks associated with a standard transthoracic echocardiogram. You may feel some discomfort similar to pulling off an adhesive bandage when the technician removes the electrodes placed on your chest during the procedure.

If you have a transesophageal echocardiogram, your throat may be sore for a few hours afterward. Rarely, the tube may scrape the inside of your throat. Your oxygen level will be monitored during the exam to check for any breathing problems caused by the sedation medication.

During a stress echocardiogram, exercise or medication — not the echocardiogram itself — may temporarily cause an irregular heartbeat. Serious complications, such as a heart attack, are rare.

How do you prepare for the test?
No special preparations are necessary for a standard transthoracic echocardiogram. Your doctor will ask you not to eat for a few hours beforehand if you’re having a transesophageal or stress echocardiogram. If you’ll be walking on a treadmill during a stress echocardiogram, wear comfortable shoes. If you’re having a transesophageal echocardiogram, you won’t be able to drive afterward because of the sedating medication you’ll receive. Be sure to make arrangements to get home before you have your test.

What happens when the test is performed?

During the procedure
An echocardiogram can be done in the doctor’s office or a hospital. After undressing from the waist up, you’ll lie on an examining table or bed. The technician will attach sticky patches (electrodes) to your body to help detect and conduct the electrical currents of your heart.

If you’ll have a transesophageal echocardiogram, your throat will be numbed with a numbing spray or gel. You’ll likely be given a sedative to help you relax.

During the echocardiogram, the technician will dim the lights to better view the image on the monitor. You may hear a pulsing “whoosh” sound, which is the machine recording the blood flowing through your heart.

Most echocardiograms take less than an hour, but the timing may vary depending on your condition. During a transthoracic echocardiogram, you may be asked to breathe in a certain way or to roll onto your left side. Sometimes the transducer must be held very firmly against your chest. This can be uncomfortable – but it helps the technician produce the best images of your heart.

After the procedure
If your echocardiogram is normal, no further testing may be needed. If the results are concerning, you may be referred to a heart specialist (cardiologist) for further assessment. Treatment depends on what’s found during the exam and your specific signs and symptoms. You may need a repeat echocardiogram in several months or other diagnostic tests, such as a cardiac computerized tomography (CT) scan or coronary angiogram.

How long is it before the result of the test is known?
If a doctor does the test, you might get some results immediately. If a technician performs the test, he or she records the echocardiogram on a videotape for a cardiologist to review later on. In this case, you’ll probably receive results in several days.

Results:
Your doctor will look for healthy heart valves and chambers, as well as normal heartbeats. Information from the echocardiogram can reveal many aspects of your heart health, including:

*Heart size. Weakened or damaged heart valves, high blood pressure or other diseases can cause the chambers of your heart to enlarge. Your doctor can use an echocardiogram to evaluate the need for treatment or monitor treatment effectiveness.

*Pumping strength. An echocardiogram can help your doctor determine your heart’s pumping strength. Specific measurements may include the percentage of blood that’s pumped out of a filled ventricle with each heartbeat (ejection fraction) or the volume of blood pumped by the heart in one minute (cardiac output). If your heart isn’t pumping enough blood to meet your body’s needs, heart failure may be a concern.

*Damage to the heart muscle. During an echocardiogram, your doctor can determine whether all parts of the heart wall are contributing equally to your heart’s pumping activity. Parts that move weakly may have been damaged during a heart attack or be receiving too little oxygen. This may indicate coronary artery disease or various other conditions.

*Valve problems. An echocardiogram shows how your heart valves move as your heart beats. Your doctor can determine if the valves open wide enough for adequate blood flow or close fully to prevent blood leakage. Abnormal blood flow patterns and conditions such as aortic valve stenosis — when the heart’s aortic valve is narrowed — can be detected as well.

*Heart defects. Many heart defects can be detected with an echocardiogram, including problems with the heart chambers, abnormal connections between the heart and major blood vessels, and complex heart defects that are present at birth. Echocardiograms can even be used to monitor a baby’s heart development before birth.

Resources:
https://www.health.harvard.edu/fhg/diagnostics/echocardiogram.shtml
http://www.mayoclinic.com/health/echocardiogram/MY00095

http://www.sads.org.uk/cardiac_tests.htm

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Ailmemts & Remedies Pediatric

Down Syndrome

Boy assembling a book case
Image via Wikipedia

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Definition
Down syndrome is the most common cause of mental retardation and malformation in a newborn. It occurs because of the presence of an extra chromosome.

.CLICK & SEE

Chromosomes are the units of genetic information that exist within every cell of the body. Twenty-three distinctive pairs, or 46 total chromosomes, are located within the nucleus (central structure) of each cell. When a baby is conceived by the combining of one sperm cell with one egg cell, the baby receives 23 chromosomes from each parent, for a total of 46 chromosomes. Sometimes, an accident in the production of a sperm or egg cell causes that cell to contain 24 chromosomes. This event is referred to as nondisjunction. When this defective cell is involved in the conception of a baby, that baby will have a total of 47 chromosomes. The extra chromosome in Down syndrome is labeled number 21. For this reason, the existence of three such chromosomes is sometimes referred to as Trisomy 21.

In a very rare number of Down syndrome cases (about 1–2%), the original egg and sperm cells are completely normal. The problem occurs sometime shortly after fertilization; during the phase where cells are dividing rapidly. One cell divides abnormally, creating a line of cells with an extra chromosome 21. This form of genetic disorder is called a mosaic. The individual with this type of Down syndrome has two types of cells: those with 46 chromosomes (the normal number), and those with 47 chromosomes (as occurs in Down syndrome). Some researchers have suggested that individuals with this type of mosaic form of Down syndrome have less severe signs and symptoms of the disorder.

Another relatively rare genetic accident which can cause Down syndrome is called translocation. During cell division, the number 21 chromosome somehow breaks. A piece of the 21 chromosome then becomes attached to another chromosome. Each cell still has 46 chromosomes, but the extra piece of chromosome 21 results in the signs and symptoms of Down syndrome. Translocations occur in about 3–4% of cases of Down syndrome.

Down syndrome occurs in about one in every 800–1,000 births. It affects an equal number of boys and girls. Less than 25% of Down syndrome cases occur due to an extra chromosome in the sperm cell. The majority of cases of Down syndrome occur due to an extra chromosome 21 within the egg cell supplied by the mother (nondisjunction). As a woman’s age (maternal age) increases, the risk of having a Down syndrome baby increases significantly. For example, at younger ages, the risk is about one in 4,000. By the time the woman is age 35, the risk increases to one in 400; by age 40 the risk increases to one in 110; and by age 45 the risk becomes one in 35. There is no increased risk of either mosaicism or translocation with increased maternal age.

Causes and Symptoms:-
While Down syndrome is a chromosomal disorder, a baby is usually identified at birth through observation of a set of common physical characteristics. Babies with Down syndrome tend to be overly quiet, less responsive, with weak, floppy muscles. Furthermore, a number of physical signs may be present. These include:

*flat appearing face
*small head
*flat bridge of the nose
*smaller than normal, low-set nose
*small mouth, which causes the tongue to stick out and to appear overly large
*upward slanting eyes
*extra folds of skin located at the inside corner of each eye, near the nose (called epicanthal folds)
*rounded cheeks
*small, misshapen ears
*small, wide hands
*an unusual, deep crease across the center of the palm (called a simian crease)
*a malformed fifth finger
*a wide space between the big and the second toes
*unusual creases on the soles of the feet
*overly-flexible joints (sometimes referred to as being double-jointed)
*ahorter than normal height

Other types of defects often accompany Down syndrome. About 30–50% of all children with Down syndrome are found to have heart defects. A number of different heart defects are common in Down syndrome, including abnormal openings (holes) in the walls that separate the heart’s chambers (atrial septal defect, ventricular septal defect). These result in abnormal patterns of blood flow within the heart. The abnormal blood flow often means that less oxygen is sent into circulation throughout the body. Another heart defect that occurs in Down syndrome is called Tetralogy of Fallot. Tetralogy of Fallot consists of a hole in the heart, along with three other major heart defects.

Malformations of the gastrointestinal tract are present in about 5–7% of children with Down syndrome. The most common malformation is a narrowed, obstructed duodenum (the part of the intestine into which the stomach empties). This disorder, called duodenal atresia, interferes with the baby’s milk or formula leaving the stomach and entering the intestine for digestion. The baby often vomits forcibly after feeding, and cannot gain weight appropriately until the defect is repaired.

Other medical conditions that occur in patients with Down syndrome include an increased chance of developing infections, especially ear infections and pneumonia; certain kidney disorders; thyroid disease (especially low or hypothyroid); hearing loss; vision impairment requiring glasses (corrective lenses); and a 20-times greater chance of developing leukemia (a blood disorder).

Development in a baby and child with Down syndrome occurs at a much slower than normal rate. Because of weak, floppy muscles (hypotonia), babies learn to sit up, crawl, and walk much later than their normal peers. Talking is also quite delayed. The level of mental retardation is considered to be mild-to-moderate in Down syndrome. The actual IQ range of Down syndrome children is quite varied, but the majority of such children are in what is sometimes known as the trainable range. This means that most people with Down syndrome can be trained to do regular self-care tasks, function in a socially appropriate manner in a normal home environment, and even hold simple jobs.

As people with Down syndrome age, they face an increased chance of developing the brain disease called Alzheimer’s (sometimes referred to as dementia or senility). Most people have a six in 100 risk of developing Alzheimer’s, but people with Down syndrome have a 25 in 100 chance of the disease. Alzheimer’s disease causes the brain to shrink and to break down. The number of brain cells decreases, and abnormal deposits and structural arrangements occur. This process results in a loss of brain functioning. People with Alzheimer’s have strikingly faulty memories. Over time, people with Alzheimer’s disease will lapse into an increasingly unresponsive state. Some researchers have shown that even Down syndrome patients who do not appear to have Alzheimer’s disease have the same changes occurring to the structures and cells of their brains.

As people with Down syndrome age, they also have an increased chance of developing a number of other illnesses, including cataracts, thyroid problems, diabetes, and seizure disorders.

Diagnosises:-
Diagnosis is usually suspected at birth, when the characteristic physical signs of Down syndrome are noted. Once this suspicion has been raised, genetic testing (chromosome analysis) can be undertaken in order to verify the presence of the disorder. This testing is usually done on a blood sample, although chromosome analysis can also be done on other types of tissue, including skin. The cells to be studied are prepared in a laboratory. Chemical stain is added to make the characteristics of the cells and the chromosomes stand out. Chemicals are added to prompt the cells to go through normal development, up to the point where the chromosomes are most visible, prior to cell division. At this point, they are examined under a microscope and photographed. The photograph is used to sort the different sizes and shapes of chromosomes into pairs. In most cases of Down syndrome, one extra chromosome 21 will be revealed. The final result of such testing, with the photographed chromosomes paired and organized by shape and size, is called the individual’s karyotype.

Two types of prenatal tests are used to detect Down syndrome in a fetus: screening tests and diagnostic tests. Screening tests estimate the risk that a fetus has DS; diagnostic tests can tell whether the fetus actually has the condition.

Screening tests are cost-effective and easy to perform. But because they can’t give a definitive answer as to whether a baby has DS, these tests are used to help parents decide whether to have more diagnostic tests.

Diagnostic tests are about 99% accurate in detecting Down syndrome and other chromosomal abnormalities. However, because they’re performed inside the uterus, they are associated with a risk of miscarriage and other complications.

For this reason, invasive diagnostic testing previously was generally recommended only for women age 35 or older, those with a family history of genetic defects, or those who’ve had an abnormal result on a screening test.

However, the American College of Obstetrics and Gynecology (ACOG) now recommends that all pregnant women be offered screening with the option for invasive diagnostic testing for Down syndrome, regardless of age.

If you’re unsure about which test, if any, is right for you, your doctor or a genetic counselor can help you sort through the pros and cons of each.

Screening tests include:-
*Nuchal translucency testing. This test, performed between 11 and 14 weeks of pregnancy, uses ultrasound to measure the clear space in the folds of tissue behind a developing baby’s neck. (Babies with DS and other chromosomal abnormalities tend to accumulate fluid there, making the space appear larger.) This measurement, taken together with the mother’s age and the baby’s gestational age, can be used to calculate the odds that the baby has DS. Nuchal translucency testing is usually performed along with a maternal blood test.

*The triple screen or quadruple screen (also called the multiple marker test). These tests measure the quantities of normal substances in the mother’s blood. As the names imply, triple screen tests for three markers and quadruple screen includes one additional marker and is more accurate. These tests are typically offered between 15 and 18 weeks of pregnancy.

*Integrated screen. This uses results from first trimester screening tests (with or without nuchal translucency) and blood tests with second trimester quad screen to come up with the most accurate screening results.

*A genetic ultrasound. A detailed ultrasound is often performed at 18 to 20 weeks in conjunction with the blood tests, and it checks the fetus for some of the physical traits abnormalities associated with Down syndrome.

Diagnostic tests include:-
*Chorionic villus sampling (CVS). CVS involves taking a tiny sample of the placenta, either through the cervix or through a needle inserted in the abdomen. The advantage of this test is that it can be performed during the first trimester, between 8 and 12 weeks. The disadvantage is that it carries a slightly greater risk of miscarriage as compared with amniocentesis and has other complications.

*Amniocentesis. This test, performed between 15 and 20 weeks of pregnancy, involves the removal of a small amount of amniotic fluid through a needle inserted in the abdomen. The cells can then be analyzed for the presence of chromosomal abnormalities. Amniocentesis carries a small risk of complications, such as preterm labor and miscarriage.

*Percutaneous umbilical blood sampling (PUBS). Usually performed after 20 weeks, this test uses a needle to retrieve a small sample of blood from the umbilical cord. It carries risks similar to those associated with amniocentesis.
After a baby is born, if the doctor suspects DS based on the infant’s physical characteristics, a karyotype — a blood or tissue sample stained to show chromosomes grouped by size, number, and shape — can be performed to verify the diagnosis.

Treatment:-
No treatment is available to cure Down syndrome. Treatment is directed at addressing the individual concerns of a particular patient. For example, heart defects will many times require surgical repair, as will duodenal atresia. Many Down syndrome patients will need to wear glasses to correct vision. Patients with hearing impairment benefit from hearing aids.

At one time, most children with Down syndrome did not live past childhood. Many would often become sick from infections. Others would die from their heart problems or other problems they had at birth. Today, most of these health problems can be treated and most children who have it will grow into adulthood.

Medicines can help with infections and surgery can correct heart, stomach, and intestinal problems. If the person gets leukaemia, there are medical treatments that can be very successful. Someone with Down syndrome has a good chance of living to be 50 years old or more.

A new drug, referred to as a “smart drug,” has been receiving some attention in the treatment of Down syndrome patients. This drug, piracetam, has not been proven to increase intellectual ability, despite testimonials that have been receiving attention on television and the Internet. Piracetam has not been approved for use in the United States, although it is being sold via the Internet. The National Down Syndrome Society and the National Down Syndrome Congress do not recommend the use of this drug as of 2001.

While some decades ago, all Down syndrome children were quickly placed into institutions for lifelong care. Research shows very clearly that the best outlook for children with Down syndrome is a normal family life in their own home. This requires careful support and education of the parents and the siblings. It is a life-changing event to learn that a new baby has a permanent condition that will effect essentially all aspects of his or her development. Some community groups exist to help families deal with the emotional effects of this new information, and to help plan for the baby’s future. Schools are required to provide services for children with Down syndrome, sometimes in separate special education classrooms, and sometimes in regular classrooms (this is called mainstreaming or inclusion).

Prognosis:-
The prognosis in Down syndrome is quite variable, depending on the types of complications (heart defects, susceptibility to infections, development of leukemia) of each individual baby. The severity of the retardation can also vary significantly. Without the presence of heart defects, about 90% of children with Down syndrome live into their teens. People with Down syndrome appear to go through the normal physical changes of aging more rapidly, however. The average age of death for an individual with Down syndrome is about 50–55 years.

Still, the prognosis for a baby born with Down syndrome is better than ever before. Because of modern medical treatments, including antibiotics to treat infections and surgery to treat heart defects and duodenal atresia, life expectancy has greatly increased. Community and family support allows people with Down syndrome to have rich, meaningful relationships. Because of educational programs, some people with Down syndrome are able to hold jobs.

Men with Down syndrome appear to be uniformly sterile (meaning that they are unable to have offspring). Women with Down syndrome, however, are fully capable of having babies. About 50% of these babies, however, will also be born with Down syndrome.

Prevention:-
Efforts at prevention of Down syndrome are aimed at genetic counseling of couples who are preparing to have babies. A counselor needs to inform a woman that her risk of having a baby with Down syndrome increases with her increasing age. Two types of testing is available during a pregnancy to determine if the baby being carried has Down syndrome.

Screening tests are used to estimate the chance that an individual woman will have a baby with Down syndrome. At 14–17 weeks of pregnancy, measurements of a substance called AFP (alpha-fetoprotein) can be performed. AFP is normally found circulating in the blood of a pregnant woman, but may be unusually high or low with certain disorders. Carrying a baby with Down syndrome often causes AFP to be lower than normal. This information alone, or along with measurements of two other hormones, is considered along with the mother’s age to calculate the risk of the baby being born with Down syndrome. These results are only predictions, and are only correct about 60% of the time.

The only way to definitively establish (with about 98–99% accuracy) the presence or absence of Down syndrome in a developing baby, is to test tissue from the pregnancy itself. This is usually done either by amniocentesis or chorionic villus sampling (CVS). In amniocentesis, a small amount of the fluid in which the baby is floating is withdrawn with a long, thin needle. In chorionic villus sampling, a tiny tube is inserted into the opening of the uterus to retrieve a small sample of the placenta (the organ that attaches the growing baby to the mother via the umbilical cord, and provides oxygen and nutrition). Both amniocentesis and CVS allow the baby’s own karyotype to be determined. A couple must then decide whether to use this information in order to begin to prepare for the arrival of a baby with Down syndrome, or to terminate the pregnancy.

Once a couple has had one baby with Down syndrome, they are often concerned about the likelihood of future offspring also being born with the disorder. Most research indicates that this chance remains the same as for any woman at a similar age. However, when the baby with Down syndrome has the type that results from a translocation, it is possible that one of the two parents is a carrier of that defect. A carrier “carries” the genetic defect, but does not actually have the disorder. When one parent is a carrier of a translocation, the chance of future offspring having Down syndrome is greatly increased. The specific risk will have to be calculated by a genetic counselor.

Research:-
Main article: Research of Down syndrome-related genes
Down syndrome is “a developmental abnormality characterized by trisomy of human chromosome 21″ (Nelson 619). The extra copy of chromosome-21 leads to an over expression of certain genes located on chromosome-21.

Research by Arron et al shows that some of the phenotypes associated with Down Syndrome can be related to the dysregulation of transcription factors (596), and in particular, NFAT. NFAT is controlled in part by two proteins, DSCR1 and DYRK1A; these genes are located on chromosome-21 (Epstein 582). In people with Down Syndrome, these proteins have 1.5 times greater concentration than normal (Arron et al. 597). The elevated levels of DSCR1 and DYRK1A keep NFAT primarily located in the cytoplasm rather than in the nucleus, preventing NFATc from activating the transcription of target genes and thus the production of certain proteins (Epstein 583).

This dysregulation was discovered by testing in transgenic mice that had segments of their chromosomes duplicated to simulate a human chromosome-21 trisomy (Arron et al. 597). A test involving grip strength showed that the genetically modified mice had a significantly weaker grip, much like the characteristically poor muscle tone of an individual with Down Syndrome (Arron et al. 596). The mice squeezed a probe with a paw and displayed a .2 newton weaker grip (Arron et al. 596). Down syndrome is also characterized by increased socialization. When modified and unmodified mice were observed for social interaction, the modified mice showed as much as 25% more interactions as compared to the unmodified mice (Arron et al. 596).

The genes that may be responsible for the phenotypes associated may be located proximal to 21q22.3. Testing by Olson et al. in transgenic mice show the duplicated genes presumed to cause the phenotypes are not enough to cause the exact features. While the mice had sections of multiple genes duplicated to approximate a human chromosome-21 triplication, they only showed slight craniofacial abnormalities (688-690). The transgenic mice were compared to mice that had no gene duplication by measuring distances on various points on their skeletal structure and comparing them to the normal mice (Olson et al. 687). The exact characteristics of Down Syndrome were not observed, so more genes involved for Down Syndrome phenotypes have to be located elsewhere.

Reeves et al, using 250 clones of chromosome-21 and specific gene markers, were able to map the gene in mutated bacteria. The testing had 99.7% coverage of the gene with 99.9995% accuracy due to multiple redundancies in the mapping techniques. In the study 225 genes were identified (311-313).

The search for major genes that may be involved in Down syndrome symptoms is normally in the region 21q21–21q22.3. However, studies by Reeves et al. show that 41% of the genes on chromosome-21 have no functional purpose, and only 54% of functional genes have a known protein sequence. Functionality of genes was determined by a computer using exon prediction analysis (312). Exon sequence was obtained by the same procedures of the chromosome-21 mapping.

Research has led to an understanding that two genes located on chromosome-21, that code for proteins that control gene regulators, DSCR1 and DYRK1A can be responsible for some of the phenotypes associated with Down Syndrome. DSCR1 and DYRK1A cannot be blamed outright for the symptoms; there are a lot of genes that have no known purpose. Much more research would be needed to produce any appropriate or ethically acceptable treatment options.

Recent use of transgenic mice to study specific genes in the Down syndrome critical region has yielded some results. APP is an Amyloid beta A4 precursor protein. It is suspected to have a major role in cognitive difficulties. Another gene, ETS2 is Avian Erythroblastosis Virus E26 Oncogene Homolog 2. Researchers have “demonstrated that over-expression of ETS2 results in apoptosis. Transgenic mice over-expressing ETS2 developed a smaller thymus and lymphocyte abnormalities, similar to features observed in Down syndrome.”

Vitamin supplements, in particular supplemental antioxidants and folinic acid, have been shown to be ineffective in the treatment of Down syndrome.

Sociological and cultural aspects:-
Advocates for people with Down syndrome point to various factors, such as additional educational support and parental support groups to improve parenting knowledge and skills. There are also strides being made in education, housing, and social settings to create environments which are accessible and supportive to people with Down syndrome. In most developed countries, since the early twentieth century many people with Down syndrome were housed in institutions or colonies and excluded from society. However, since the early 1960s parents and their organizations (such as MENCAP), educators and other professionals have generally advocated a policy of inclusion, bringing people with any form of mental or physical disability into general society as much as possible. In many countries, people with Down syndrome are educated in the normal school system; there are increasingly higher-quality opportunities to move from special (segregated) education to regular education settings.

Despite these changes, the additional support needs of people with Down syndrome can still pose a challenge to parents and families. Although living with family is preferable to institutionalization, people with Down syndrome often encounter patronizing attitudes and discrimination in the wider community.

The first World Down Syndrome Day was held on 21 March 2006. The day and month were chosen to correspond with 21 and trisomy respectively. It was proclaimed by European Down Syndrome Association during their European congress in Palma de Mallorca (febr. 2005). In the United States, the National Down Syndrome Society observes Down Syndrome Month every October as “a forum for dispelling stereotypes, providing accurate information, and raising awareness of the potential of individuals with Down syndrome.” In South Africa, Down Syndrome Awareness Day is held every October 20.[49] Organizations such as Special Olympics Hawaii provide year-round sports training for individuals with intellectual disabilities such as down syndrome.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://www.answers.com/topic/down-syndrome-diagnosis
http://kidshealth.org/parent/medical/genetic/down_syndrome.html
http://www.charliebrewersworld.com/page4.htm
http://en.wikipedia.org/wiki/Down_syndrome

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