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Health Library A to Z

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  • Abrasions
  • An abrasion is a superficial rub or wearing off of the skin, usually caused by a scrape or a brush burn. Abrasions are usually minor injuries that can be treated at home.

  • Acute Bronchitis in Children
  • Bronchitis is an inflammation of the large breathing tubes (bronchi) in the lungs. Short-term (acute) bronchitis means that the symptoms often develop quickly and don't last long.

  • Alpha Thalassemia in Children
  • Alpha thalassemia is an inherited blood disorder. This means it is passed down through the parent’s genes. It causes anemia in affected children. Learn more about symptoms, diagnosis, and treatment.

  • Anemia in Children
  • Anemia is a common problem in children. A child who has anemia doesn't have enough red blood cells or hemoglobin. Read on to learn more about causes, symptoms, diagnosis, and treatment.

  • Aplastic Anemia in Children
  • Aplastic anemia is a serious condition in which the bone marrow doesn’t make enough new blood cells. Read on for details about causes, symptoms, diagnosis, and treatment.

  • Apnea of Prematurity
  • Apnea is a term that means breathing has stopped for more than 20 seconds. It can happen in full-term babies, but it is more common in premature babies. The more premature the baby, the greater the chances that apnea will occur.

  • Arrhythmias in Children
  • An arrhythmia is an abnormal rhythm of the heart. In an arrhythmia, abnormal electrical signals through the heart muscle may cause the heart to beat too fast (tachycardia), too slow (bradycardia), or irregularly. Read on to learn more.

  • Atrial Septal Defect (ASD) in Children
  • The atrial septum is the wall between the two upper chambers of the heart (right and left atria). An atrial septal defect (ASD) is an abnormal hole in this wall. ASD is a heart problem that is present at birth (congenital). Read on for details about symptoms, diagnosis, and treatment.

  • Bacterial Endocarditis in Children
  • Bacterial endocarditis is an infection of the lining of the heart (endocardium), and the heart valves. It does not happen very often, but when it does, it can cause serious heart damage.

  • Birthmarks
  • Detailed information on birthmarks and the different types, including vascular birthmarks, hemangiomas, and port-wine stains.

  • Black Eye (Ecchymosis)
  • A black eye should be seen by a healthcare provider to make sure no injury has happened to the eye itself. Most black eyes heal completely and don't cause any damage.

  • Branchial Cleft Abnormalities in Children
  • A branchial cleft abnormality is a cluster of abnormally formed tissue in the neck. A branchial cleft abnormality is a birth defect. It happens when the area doesn't form as it should during the early stages of an embryo’s development.

  • Bronchiolitis in Children
  • Bronchiolitis is an infection of the lungs. It's when your child has swelling in the smaller airways (bronchioles) of the lung. This swelling blocks air in the smaller airways.

  • Brown Recluse and Black Widow Spider Bites in Children
  • Most spiders in the U.S. are poisonous. The fangs of most spiders are too short or too fragile to break through human skin. Or their poison (venom) is too weak to cause damage. Most spider bites cause only minor, local reactions. But bites from the black widow and the brown recluse spiders can cause serious problems. Read on to learn more.

  • Bruises
  • A bruise is a collection of blood underneath the skin that is caused by injury to an area of the body. Sometimes enough bleeding occurs so that a lump also forms.

  • Candidiasis in Children
  • Candidiasis is an infection caused by yeast called Candida. Candida normally causes no harm, and is found on the skin, vaginal area, and digestive system. But in some cases, it can overgrow. This can cause a rash, itching, and other symptoms.

  • Cardiac Catheterization for Children
  • Cardiac catheterization is a procedure in which a long, flexible tube (catheter) is put into a blood vessel. The doctor then guides the catheter into the heart to find and treat heart problems.

  • Cat Scratch Disease in Children
  • Cat scratch disease is a bacterial infection carried in cat saliva. It is passed from a cat bite or scratch to a human. It can also result from a fleabite, but cats are the main source.

  • Cataracts in Children
  • A cataract is a clouding over the lens of the eye. This area is normally clear (transparent). Some cataracts are small and don’t cause any trouble with vision. Others can cause visual problems in children. Cataracts are rare in children.

  • Cellulitis of the Eye in Children
  • Cellulitis is a serious type of infection and inflammation. It can occur in various parts of the body. When it occurs in the eyelid and tissues in the front part of the eye area, it’s called preseptal cellulitis. When it occurs behind and around the eye in the eye socket (orbit), it’s called orbital cellulitis. Both of these conditions are serious.

  • Cleft Lip and Palate in Children
  • Cleft lip and palate are openings or splits in the upper lip or roof of the mouth (palate). A child can be born with a cleft lip, cleft palate, or both. Cleft lip and palate may be the only birth defects, or they may happen with other defects.

  • Common Cold in Children
  • The common cold is one of the most common illnesses in children. Most children will have at least 6 to 8 colds a year.

  • Dermoid Cyst in Children
  • A dermoid cyst is a collection of tissue under the skin. It may contain hair follicles, oil, and sweat glands.

  • Diphtheria in Children
  • A detailed look at diphtheria, including symptoms, treatment, and a vaccination schedule.

  • Disorders of Sex Development
  • When a child's gender is in question at birth, the child has atypical genitalia (ambiguous genitalia). This means that the genitals don't seem to be clearly male or female.

  • Dysphagia in Children
  • Dysphagia means trouble swallowing. This condition happens when food or liquids can’t pass easily from your child’s mouth, into the throat, down the esophagus, and into the stomach when swallowing.

  • Endoscopic Sinus Surgery for Children
  • Endoscopic sinus surgery is a procedure to open the passages of the nose and sinuses. It is done to treat long-term (chronic) sinus infections. An ear, nose, and throat specialist (ENT) does the surgery.

  • Epiglottitis in Children
  • The epiglottis is a flap of cartilage at the base of the tongue at the very back of the throat. When the epiglottis becomes swollen and inflamed, it is called epiglottitis.

  • Ewing Sarcoma in Children
  • Ewing sarcoma is a rare type of cancer. It’s most common in children and teens between ages 10 and 19. It usually grows in bone, but it can also grow in soft tissue that’s connected to the bone. Read on to learn about symptoms, diagnosis, and treatment.

  • Hand-Foot-and-Mouth Disease in Children
  • Hand-foot-and-mouth disease is an illness caused by a virus. It causes a rash on the palms of the hands and soles of the feet. It can also occur in the diaper area, and on the legs and arms.

  • Hemolytic Disease of the Newborn (HDN)
  • Hemolytic disease of the newborn (HDN) is a blood problem in newborns. It occurs when your baby's red blood cells break down at a fast rate.  It’s also called erythroblastosis fetalis.

  • Hemolytic Uremic Syndrome in Children
  • Hemolytic uremic syndrome (HUS) is a rare condition that can lead to kidney failure. The syndrome harms the small structures and vessels inside the kidneys. HUS causes red blood cells to clog the tiny blood vessels in the kidneys. It may cause damage to the kidney tissues.

  • Hemophilia
  • Hemophilia is an inherited bleeding disorder. People with hemophilia can’t stop bleeding because they don’t have enough clotting factor in their blood. Clotting factors are needed for blood to clot. Blood clots to prevent excessive bleeding.

  • Holter Monitoring for Children
  • Holter monitoring is a way to continuously check the electrical activity of the heart. Your child will wear a small device called a Holter monitor for at least 24 to 48 hours. The device constantly checks your child's heart during this time.

  • Hydrocele in Children
  • A hydrocele is fluid buildup in the thin pouch that holds the testes in the scrotum. Up to 1 in 10 baby boys have a hydrocele at birth. In most cases, it goes away without treatment in the first year.

  • Hypocalcemia in the Newborn
  • Hypocalcemia is when a person doesn't have enough calcium in the blood. In babies, it’s called neonatal hypocalcemia. Your baby can get it at different times and from different causes.

  • Hypoglycemia in a Newborn Baby
  • Hypoglycemia is when the level of sugar (glucose) in the blood is too low. Glucose is the main source of fuel for the brain and the body. In a newborn baby, low blood sugar can happen for many reasons. It can cause problems such as shakiness, blue color to the skin, and breathing and feeding problems. Read on to learn more.

  • Hypoglycemia in Children
  • Hypoglycemia is when the level of sugar (glucose) in the blood is too low. Hypoglycemia can be a condition by itself. Or it can be a complication of diabetes or other disorder. Read on to learn more.

  • Impetigo in Children
  • Impetigo is a skin infection. When it affects just the surface, it’s called superficial impetigo. Impetigo can also affect deeper parts of the skin. This is called ecthyma. It may occur on healthy skin. Or it may occur where the skin was injured by a cut, scrape, or insect bite.

  • Inguinal Hernia in Children
  • A hernia occurs when a part of the intestine pushes through a weakness in the belly (abdominal) muscles. A hernia in the groin area is called an inguinal hernia.

  • Insect Stings and Allergic Reactions in Children
  • For most children, the reaction to a sting is brief, with redness and swelling followed by pain and itching. Others may have an allergic reaction that is life-threatening. Read on for details.

  • Intussusception in Children
  • Intussusception is a serious problem in the intestine. It's the most common abdominal emergency in early childhood. Read on to learn more.

  • Juvenile Dermatomyositis
  • Juvenile dermatomyositis (JDM) is a rare disease that causes muscle inflammation and a skin rash.

  • Lead Poisoning in Children
  • Lead poisoning is a totally preventable disease. Children ages 1 to 3 who live in low-income housing built before 1978 are especially at risk. Read on to learn more.

  • Leukemia in Children
  • Leukemia is cancer of the blood. It’s the most common form of cancer in childhood. The cancer cells grow in bone marrow and go into the blood.

  • Lung Transplantation in Children
  • A detailed look at lung transplantation in children, including why it is advised, information about the surgery, and the long-term outlook for a child after a lung transplant.

  • Lymphatic Malformations in Children
  • A lymphatic malformation is a lymphatic vessel that isn't formed correctly. The vessel traps the lymph fluid and causes cysts to form. Your child may have 1 or more of these cysts.

  • Meckel Diverticulum
  • Meckel diverticulum is a small pouch in the wall of the intestine. It’s near where the small and large intestines meet. This condition is the most common birth defect of the digestive system. It happens to about 1 in 50 babies.

  • Micropenis in Children
  • A micropenis is a penis that is smaller than normal. A penis length of less than 0.75 inches is considered micropenis.

  • Mushroom Poisoning in Children
  • Mushroom poisoning happens when a child eats a mushroom that has poisons (toxins). Here's what you need to know, from symptoms to diagnosis and treatment.

  • Natal Teeth
  • Natal teeth are teeth that are present when a baby is born. The teeth are often not fully developed and may have a weak root.

  • Necrotizing Enterocolitis in the Newborn
  • Necrotizing enterocolitis (NEC) is a serious illness in newborns. It happens when tissue in the large intestine (colon) gets inflamed. This inflammation damages and sometimes kills the tissue in your baby’s colon.

  • Neonatal Abstinence Syndrome
  • Neonatal abstinence syndrome is what happens when babies are exposed to drugs in the uterus before birth. Babies can then go through drug withdrawal after birth.

  • Newborn Reflexes
  • Ever wonder why your baby flings his arms out sideways when startled? This reaction--called the Moro reflex--is one of many natural reflexes your newborn should exhibit. Read on to learn about common newborn reflexes and what they mean.

  • Newborn Screening Tests
  • A national program exists to screen all newborns for certain disorders in the first few days of life.

  • Normal Breast Development
  • Breast development occurs in distinct stages, first before birth, and again at puberty and during the childbearing years. Changes also occur to the breasts during menstruation and when a woman reaches menopause.

  • Normal Vision
  • To understand how certain problems can affect your child's vision, it’s important to know how normal vision happens.

  • Osteosarcoma (Osteogenic Sarcoma) in Children
  • Osteosarcoma is cancer of the bone. It is rare, but it is the most common type of bone cancer in children and teens. Learn more about risks, symptoms, diagnosis, treatment, and prevention.

  • Overuse Injuries
  • Detailed information on overuse injuries in children, including jumper's knee, patellar tendonitis, little leaguers' elbow or shoulder, and more.

  • Pilomatrixoma in Children
  • A pilomatrixoma is a slow-growing, hard lump found under the skin. It is most common on the face and neck, but it may be on other parts of the body. Read on to learn more.

  • Pneumothorax in Children
  • A pneumothorax is an air leak in the lungs. It's when air from the lungs leaks into the chest area.

  • Posttraumatic Stress Disorder (PTSD) in Children
  • Posttraumatic stress disorder (PTSD) is a mental health problem. A child with PTSD has constant, scary thoughts and memories of a past event. The child finds the event terrifying, either physically or emotionally.

  • Prescription Drug Addiction
  • Three kinds of prescription medicines are potentially addictive: opioids, tranquilizers, and stimulants. Here's what you should know.

  • Pulmonary Atresia
  • Pulmonary atresia (PA) is a heart defect. It happens when the fetal heart doesn’t form as it should during the first 8 weeks of pregnancy.

  • Puncture Wounds in Children
  • A puncture wound is a deep wound made by a sharp object. This type of wound may become infected easily because dirt and germs are carried deep into the tissues.

  • Pyloric Stenosis
  • Pyloric stenosis is a problem that causes forceful vomiting. It affects babies from birth to 6 months of age. It can lead to dehydration. This condition is the second most common reason why newborns have surgery.

  • Respiratory Syncytial Virus (RSV) in Children
  • RSV is a viral illness that causes symptoms such as trouble breathing. It’s the most common cause of inflammation of the small airways in the lungs (bronchiolitis) and pneumonia in babies.

  • School Refusal
  • There are many reasons why a child would feel anxious and not want to go to school. Read on to learn more about school refusal.

  • Scoliosis in Children
  • Scoliosis is a deformity of the backbone (spine). It's when the spine has a side-to-side curve. The curve of the spine measures 10° or more.

  • Second-Degree Burn in Children
  • A burn is damage to tissues of the body caused by contact with things such as heat, radiation, or chemicals. A second-degree burn affects the outer layer of skin (epidermis) and part of the inner layer of skin (dermis).

  • Sickle Cell Disease in Children
  • Sickle cell disease is an inherited blood disorder that is present at birth. Children with SCD make an abnormal type of hemoglobin. This is the protein in red blood cells that carries oxygen to all parts of the body.

  • Swimmer’s Ear in Children
  • Swimmer’s ear (otitis externa) is an inflammation of the external ear canal. Swimmer’s ear is caused by bacteria or fungi. Water that stays in the ear canal during swimming, for instance, may let bacteria and fungi grow.

  • Teething
  • A baby's first tooth often appears between 5 and 7 months of age. Some babies get their first tooth a little earlier and others a little later. Here's what you need to know.

  • Testicular Torsion in Children
  • Testicular torsion is a painful twisting of the testicles and spermatic cord. Torsion causes blood to not flow to the testicles. This can damage them. Treatment needs to be done right away to prevent long-lasting (permanent) injury to the testicles.

  • Thrombocytopenia in the Newborn
  • Thrombocytopenia means that a newborn baby has too few platelets in their blood. Platelets are blood cells that help the blood clot. They are made in the bone marrow.

  • Tinea Versicolor in Children
  • Tinea versicolor is a fungal skin infection. It’s caused by yeast on the skin. It occurs most often in teens and young adults. But it can happen at any time.

  • Tricuspid Atresia
  • Tricuspid atresia (TA) is a heart defect present at birth (congenital). It occurs when the tricuspid valve doesn’t form right during fetal heart development. This happens during the first 8 weeks of pregnancy. Read on to learn details about this condition.

  • Truncus Arteriosus (TA)
  • Truncus arteriosus is a heart defect that is present at birth (congenital). It occurs when there is an abnormal connection between the aorta and pulmonary artery. Normally, the aorta and the pulmonary artery are separate. Read on to learn more.

  • Type 1 Diabetes Mellitus in Children
  • Diabetes is a condition in which the body can't make enough insulin, or can't use insulin normally. Type 1 diabetes is an autoimmune disorder. The body's immune system damages the cells in the pancreas that make insulin. Insulin is a hormone. It helps sugar (glucose) in the blood get into cells of the body to be used as fuel. When glucose can’t enter the cells, it builds up in the blood. This is called high blood sugar (hyperglycemia).

  • Type 2 Diabetes in Children
  • Diabetes is a condition in which the body can't make enough insulin, or can't use insulin normally. Type 2 diabetes is a metabolic disorder. Insulin is a hormone. It helps sugar (glucose) in the blood get into cells of the body to be used as fuel. When glucose can’t enter the cells, it builds up in the blood. This is called high blood sugar (hyperglycemia). High blood sugar can cause problems all over the body.

  • Ultrafast CT Scan for Children
  • An ultrafast computed tomography (CT) scan is an imaging test that uses X-rays and a computer to look at your child’s heart. It gives the healthcare provider many details about your child’s heart that other imaging tests can’t.

  • Umbilical Cord Care
  • In a few weeks, your baby will have the cutest little belly button. But right now the healing remains of his umbilical cord need special care. Here's how to make sure the cord remainder stays infection-free.

  • Understanding Eating Disorders
  • At least 8 million people in the U.S. are living with an eating disorder. Read on for a helpful overview of the three main types of eating disorders.

  • Understanding the Teen Brain
  • Parents need to realize the rational part of a teen's brain isn't fully developed and won't be until they are 25 years old or so.

  • Undescended Testes in Children
  • Undescended testes is when one or both of the male testes have not passed down into the scrotal sac. This is a condition seen in some newborn baby boys.

  • Unwrap the Gift of Toy Safety
  • Your challenge is to find toys that your children will enjoy and that you know are safe. Read on to learn important tips that can help.

  • Upper Respiratory Disorders
  • Detailed information on the most common types of upper respiratory infections, including common cold, influenza, pharyngitis, tonsillitis, and sinusitis

  • Urticaria (Hives) in Children
  • Hives is a sudden outbreak of red, itchy, and swollen areas on the skin. It often happens as an allergic reaction from eating certain foods or taking certain medicines. Here's what you should know.

  • Vesicoureteral Reflux (VUR) in Children
  • Vesicoureteral reflux (VUR) is a condition where urine in the bladder flows in the wrong direction. It goes up into the tubes (ureters) that lead to the kidneys.

  • Vulvitis in Teens
  • Vulvitis is an inflammation of the vulva. The vulva is the outer part of the female reproductive system.

  • Why Children Bite
  • A young child may bite out of frustration or when under stress. Biting may also be an attempt to gain power, or just a way of exploring the world. Read on to learn how to respond if your child bites, no matter what the cause.

  • Your 2-Year-Old Child
  • The "terrible twos" phase of a child's life also can be the "terrific twos." Read on to learn more about how to deal with your 2-year-old child.