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Children's Health Articles
Stuttering is an interruption of the normal flow of speech, which takes on many different patterns. Commonly, it involves either saying a string of repeated sounds or making abnormal pauses during speech.
In early childhood, stuttering is sometimes part of normal speech development. In fact, about 5% of all young children go through a brief period of stuttering when they are learning to talk. Stuttering typically is first noticed between the ages of 2 and 5. It usually goes away on its own within a matter of months. In a small number of children (around 1%), stuttering continues and may get worse. Boys are more likely to stutter than girls.
Fragile X syndrome is an inherited disorder associated with mental retardation and a particular appearance. It is caused by an error in a small piece of the DNA (genetic blueprint) for the FMR1 gene. This gene is found on the X chromosome, one of the two chromosomes (X and Y) that determine gender.
In people with fragile X, a particular section of the DNA code — CGG — is "fragile" and gets repeated an unusually large number of times, compared with the normal 5 to 50 times. As a result, the FMR1 gene is not expressed (turned on), and the body cannot produce FMR1 protein, which is related to nerve function.
Depending on the number of CGG repetitions, fragile X can have a variety of physical, intellectual and behavioral effects. People with more repetitions tend to have more severe symptoms. For example, people with 200 or more CGG repetitions are described as having a full fragile X mutation and usually develop many of the symptoms of fragile X syndrome, including mental retardation. People with 59 to 200 CGG repetitions are described as having a fragile X premutation and may not show any obvious signs or symptoms of fragile X syndrome. The number of CGG repetitions can increase when the gene is passed from generation to generation, increasing the chance of developing the full fragile X mutation.
Fragile X syndrome is seen in approximately 1 in 4,000 to 6,000 males and 1 in 8,000 to 9,000 females. However, many more people carry the fragile X premutation, but show no signs or symptoms of the syndrome. Fragile X syndrome is the most common inherited cause of mental retardation in males.
Tay-Sachs disease is an inherited disease caused by an abnormal gene. People with this abnormal gene do not have an important enzyme called hexosaminidase A (HEXA) that helps to break down a fatty material called ganglioside GM2. This material builds up in the brain, and eventually damages nerve cells and causes neurological problems.
Infants usually begin to show signs of the disease between 3 months and 6 months of age. Children with Tay-Sachs disease can become deaf, blind and paralyzed, and usually die by the age of 5.
Tay-Sachs disease is an autosomal recessive inherited disorder, meaning a child inherits one copy of the abnormal gene from each parent. The parents do not actually have the disease, but carry the Tay-Sachs gene and pass it on to the baby. If both parents have the abnormal Tay-Sachs gene, there is a one-in-four chance that their child will inherit the gene from both of them and have Tay-Sachs disease.
Tay-Sachs disease is most common in Ashkenazi Jews. About one in 30 people with this ancestry carry a copy of the gene. Some non-Jewish groups also have a higher chance of carrying the disease. They include people whose ancestors were French-Canadian, from the Louisiana bayou, or from Amish populations in Pennsylvania.
Pertussis, also known as whooping cough, is a highly contagious bacterial infection that causes violent coughing. The coughing makes it hard to breathe and produces a deep "whooping" sound.
Pertussis is caused by the Bordetella pertussis or Bordetella parapertussis bacteria. Droplets of the bacteria move through the air when an infected person sneezes, coughs or talks. This is how pertussis spreads from person to person.
Pertussis can occur at any age. Serious illness is most common in infants and young children. Older children, adolescents and adults usually have milder symptoms.
The number of pertussis cases in the United States has increased in recent years. There were more than 17,000 reported cases of pertussis in 2009.
Fifth disease, also known as erythema infectiosum, is a common viral infection among school-aged children. It is caused by parvovirus B19, which spreads through direct contact with fluids or mucus from the nose or mouth of an infected person. Fifth disease causes a bright red "slapped cheek" rash that doesn't appear until an infected person is no longer contagious. Fifth disease usually is a mild illness, and some people who are infected may never realize they have it.
Osgood-Schlatter disease is a common, temporary condition that causes knee pain in older children and teenagers, especially those who play sports.
During activities that include a lot of jumping and bending — hockey, basketball, volleyball, soccer, skating, gymnastics, or ballet — the quadriceps muscle (thigh muscle) pulls tightly against the kneecap and the kneecap's anchor, the patellar tendon. The fibers of the patellar tendon are attached to the shinbone (tibia). With repeated pulling against these fiber connections, the tendon can become inflamed at or near its bone attachment. The result is pain and swelling at the tibial tuberosity, which is a raised area at the top of the shinbone. The tibial tuberosity is where the patellar tendon attaches to the bone.
A normal spine has several front-to-back curves between the neck and the pelvis. In scoliosis, the spine curves abnormally to the side or twists. Although scoliosis seems to run in some families, most cases appear for unknown reasons in children and adolescents who previously had a straight spine. Scoliosis without a known cause is called idiopathic scoliosis. Girls and boys are affected equally by idiopathic scoliosis, but girls with this condition are more likely to develop curves that get big enough to require treatment.
Croup is a common respiratory illness in children that causes a change in breathing with a hoarse voice and a brassy, barking cough. Doctors sometimes call croup laryngotracheitis because it usually involves inflammation of the larynx (voice box) and trachea (windpipe).
Croup often is divided into two broad categories:
Infectious croup is caused by an infection with a virus, bacterium or other germ. In the United States, most cases of croup are caused by a virus. These infections usually occur in the fall and winter when people spend more time indoors.
Under these conditions, the virus spreads easily through coughing and sneezing. It also can travel on dirty hands and on things that have had contact with fluids from a sick person's nose or mouth. These include used tissues, toys, drinking glasses and eating utensils.
Once the virus enters the body, it usually begins to attack the upper parts of the breathing system. For this reason, a child with croup may first complain of cold symptoms. These may include a runny nose or nasal congestion. The child also may have a low-grade fever or a mild sore throat.
Later, the virus spreads farther down the throat. The linings of the voice box and windpipe become red, swollen, narrowed and irritated. This triggers hoarseness, a barking cough, and loud, raspy breathing (stridor).
Spasmodic croup is very similar to infectious croup. It can be triggered by infection, but it isn't caused by infection. It tends to run in families, and may be triggered by an allergic reaction.
Spasmodic croup tends to come on suddenly, without fever. Sometimes it can be hard to tell spasmodic croup from infectious croup.
Infectious croup is most common in children younger than age six. Spasmodic croup usually affects children who are between three months and three years old. Before the age of three months, a child's risk of either type of croup is fairly low.