Health Library

Articles In This Section

• A to Z: Cerebral Palsy, Infantile

  Cerebral palsy (CP) is a brain disorder that affects muscle tone and motor skills (the ability to coordinate body movements).

• A to Z: Balanoposthitis

  Learn more about this inflammation of the foreskin and head of the penis.

• A to Z: Barrett’s Esophagus

  Learn about complications of acid reflux and conditions that affect the esophagus and upper gastrointestinal tract.

• A to Z: Beriberi

  Learn about complications of poor nutrition and conditions that can affect the cardiovascular and nervous systems.

• A to Z: Bipolar Disorder

  Childhood bipolar disorder leads to extreme mood shifts for boys and girls. Read more about the significant signs of bipolar disorder in children.

• A to Z: Blepharitis

  Learn about the causes of eye irritation and conditions that can affect the eyes and eyelids.

• A to Z: Blisters

  After a burn or excessive pressure to the skin, a fluid-filled pocket in the skin can form and cause pain and irritation. Learn more here.

• A to Z: Blood in Stool

  Blood in the stool means the presence of blood in a bowel movement.

• A to Z: Blood in Urine

  See: Hematuria (Blood in Urine).

• A to Z: Body Dysmorphic Disorder (BDD)

  Learn about mental health disorders and causes of low self-esteem and negative thoughts about body image.

• A to Z: Borderline Personality Disorder (BPD)

  Learn about personality disorders and complications of mental illness.

• A to Z: Botulism

  Learn about bacterial infections, foodborne illnesses, and conditions that affect the nervous system.

• A to Z: Botulism, Foodborne

  Learn about bacterial infections, foodborne illnesses, and conditions that affect the nervous system.

• A to Z: Botulism, Infant

  Learn about bacterial infections, foodborne illnesses, and conditions that affect the nervous system.

• A to Z: Botulism, Wound

  Learn about bacterial infections, foodborne illnesses, and conditions that affect the nervous system.

• A to Z: Breast Mass/Fibroadenoma

  Learn more about this type of noncancerous tumor, common in women ages 15-35.

• A to Z: Ataxia Telangiectasia

  Learn about this genetic disorder that can weaken the immune system and cause gradual worsening of balance, coordination, and speech.

• A to Z: Ataxia, Cerebellar

  See: Cerebellar Ataxia.

• A to Z: Atopic Dermatitis

  See: Eczema.

• A to Z: Atresia

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Anal

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Aortic

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Biliary

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Choanal

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Esophageal

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Pulmonary

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atresia, Tricuspid

  Learn about congenital defects and conditions that affect vessels, valves, and passages in the heart and other organs.

• A to Z: Atrial Flutter

  Atrial flutter is an abnormal heart rhythm that causes the heart to beat too fast.

• A to Z: Atrial Septal Defect (ASD)

  Learn about congenital heart defects and conditions that affect the heart and circulatory system.

• A to Z: Atrioventricular Septal Defect

  Learn about congenital heart defects and conditions that affect newborn babies.

• A to Z: Attention Deficit Hyperactivity Disorder (ADHD)

  Learn about behavioral disorders and conditions that affect children's moods, activities, and interactions.

• A to Z: Autism

  Learn about developmental disorders and conditions that affect children's moods, activities, and interactions.

• A to Z: Aortic Stenosis

  In aortic stenosis, the aortic valve is narrower than it's supposed to be and can't open all the way.

• A to Z Symptom: Back Pain

  Back pain is fairly common, and is often due to muscle strain or sprain. In students, wearing a heavy backpack is a common cause.

• A to Z: Babesiosis

  Learn about parasitic infections, tickborne illnesses, and conditions that affect the bloodstream and red blood cells.

• A to Z: Bacterial Vaginosis

  Bacterial vaginosis (BV) is an infection in the vagina.

• A to Z: Balanitis

  Learn about conditions that affect the penis and foreskin.

• A to Z: Alpha Thalassemia

  Learn about genetic disorders and diseases and conditions that affect the blood.

• A to Z: Amebiasis

  Amebiasis is an intestinal illness. People get it after eating, drinking, or touching something that's contaminated with a tiny parasite called Entamoeba histolytica.

• A to Z: Amenorrhea

  Amenorrhea is when a girl is not getting her period.

• A to Z: Amenorrhea, Primary

  Primary amenorrhea is when a girl does not start her period by age 15 or 3 years after she begins puberty.

• A to Z: Amenorrhea, Secondary

  Secondary amenorrhea is when a girl who had been getting her period stops menstruating for more than 6 months or for more than three of her usual cycles.

• A to Z: Anal Fissure

  An anal fissure is a cut or tear in the lining of the anus.

• A to Z: Anaphylaxis

  Anaphylaxis is a sudden, life-threatening reaction that is usually caused by an allergy.

• A to Z: Anemia

  Learn about anemia, a common blood disorder that happens when the level of healthy red blood cells in the body becomes too low.

• A to Z: Anorexia Nervosa

  Learn about anorexia nervosa, a type of eating disorder.

• A to Z: Appendicitis

  Appendicitis is an inflammation of the appendix, and requires surgery.

• A to Z: Apthous Ulcers (Canker Sores)

  Apthous ulcers, or canker sores, are non-contagious small ulcers that can occur inside the mouth, often causing discomfort during eating or talking.

• A to Z: Arrhythmia

  An arrhythmia is an abnormal heart rhythm usually caused by an electrical "short circuit" in the heart.

• A to Z: Arteriovenous Malformation (AVM)

  In this condition, an abnormal connection between arteries and veins causes blood to flow too quickly, leading to a risk of bleeding. Learn more here.

• A to Z: Arteritis

  Learn about conditions that affect the heart and blood vessels.

• A to Z: Arthropathy

  Learn about conditions that affect the joints, complications of diabetes, and complications of nervous system damage.

• A to Z: Asthma, Cough Variant

  People with this type of asthma have a cough but no wheezing. Learn more about it here.

• A to Z: Astrocytoma

  This type of brain tumor involves star-shaped cells of the brain that grow out of control. Learn about it here.

• A to Z Symptom: Belly Pain

  Belly pain is common and, most of the time, doesn't have a serious cause.

• A to Z: Abrasion

  An abrasion is a minor scrape of the skin that can be treated easily with proper cleaning and care.

• A to Z: Abscess

  An abscess is a collection of pus that forms as part of the body's response to an infection.

• A to Z: Abscess, Skin

  A skin abscess forms when bacteria get under the skin.

• A to Z: Abscess, Tooth

  A tooth abscess is a collection of infected material (pus) that forms at the tip of the root of a tooth.

• A to Z: Abuse, Physical

  Physical abuse can be any kind of hitting, shaking, burning, pinching, biting, choking, throwing, beating, and other actions that cause physical injury, leave marks, or cause pain.

• A to Z: Abuse, Psychological

  Psychological abuse happens when yelling and anger go too far or when people caring for kids constantly criticize, threaten, or dismiss them until their feelings of self-worth are damaged.

• A to Z: Abuse, Sexual

  Sexual abuse is sexual contact with a child or any behavior that is meant to sexually arouse the abuser.

• A to Z: Abuse, Substance

  Substance abuse is when someone drinks alcohol or smokes or takes drugs in a way that could lead to health, legal, and other problems.

• A to Z: Acanthosis Nigricans

  Acanthosis nigricans is a condition in which the skin thickens and darkens in places.

• A to Z: Acne, Infant

  Infant acne is common in babies, and usually goes away on its own without treatment or scarring.

• A to Z: Acute Febrile Mucocutaneous Lymph Node Syndrome (MCLS)

  See: Kawasaki Disease.

• A to Z: Adenovirus

  Adenoviruses are a group of viruses that can infect the membranes (tissue linings) of the respiratory tract, eyes, intestines, and urinary tract. They are common among infants and young children.

• A to Z: Adrenal Insufficiency

  Adrenal insufficiency is a condition that happens when the adrenal glands do not work properly.

• A to Z: Adynamic Ileus

  Learn about intestinal blockages and conditions that affect the digestive tract.

• A to Z: Alcohol Abuse

  Learn about alcohol abuse and consequences of excessive drinking.

• A to Z: Allergy

  With allergies, the immune system overreacts and tries to "fight" allergens, which are ordinary things that cause an allergic reaction.

• A to Z: Allergy, Drug

  Normally medicines help us treat disease, but in people with drug allergies, taking certain medicines can cause the immune system to react and harm the body.

• A to Z: Alopecia Areata

  Alopecia areata is a condition that causes hair loss on the scalp and sometimes elsewhere on the body.

• A to Z: Spinal Stenosis

  Spinal stenosis is a narrowing of the spaces in the spine, or backbone, where the spinal cord is located. Pressure placed on the spinal cord causes pain and disruption to some body functions.

• A to Z: Spondyloepiphyseal Dysplasia (SED)

  Learn about genetic disorders and conditions that affect growth and development.

• A to Z: Spondylolisthesis

  Spondylolisthesis (or "slipped vertebra") is when one of the vertebrae slips forward and out of place on the vertebra beneath it.

• A to Z: Spondylolysis

  Spondylolysis is when there is a defect of a narrow piece of bone in the vertebra.

• A to Z: Sprain

  Sprains are common injuries, especially among active older kids and teens who play sports.

• A to Z: Sprain, Ankle

  Ankle sprains are common in kids and teens who play sports. They happen when the ligaments that support the ankle get overly stretched or torn.

• A to Z: Sprain, Knee

  A knee sprain happens when a ligament is stretched or torn because the knee gets twisted, bent, or hit.

• A to Z: Sprain, Wrist

  A sprain is the stretch or partial tear of ligaments (which connect two bones). A wrist sprain happens when the ligaments that support the wrist bend or twist too far.

• A to Z: Talipes Equinovarus

  Learn about birth defects and congenital conditions that affect the feet and legs.

• A to Z: Tenosynovitis

  Learn about overuse injuries and conditions that affect the tendons and muscles.

• A to Z: Fracture, Patella (Kneecap)

  A fractured patella is a broken kneecap (the flat, round bone that protects the knee joint).

• A to Z: Acute Lymphoblastic Leukemia (ALL)

  Learn about different types of leukemia and cancers that affect the blood and bone marrow.

• A to Z: Acute Myeloid Leukemia (AML)

  Learn about different types of leukemia and cancers that affect the blood and bone marrow.

• A to Z: Brain Stem Glioma

  This type of brain tumor forms in the brain stem, the part of the brain that coordinates messages and controls processes like breathing and digestion. Learn more here.

• A to Z: Ependymoma

  This tumor forms from cells in the brain and spinal cord that make cerebrospinal fluid. Learn more about this cancer here.

• A to Z: Graft Versus Host Disease

  When a person receives a stem cell transplant, this treatable complication can make it tougher for the immune system to heal.

• A to Z: Hemophagocytic Syndrome

  Hemophagocytic syndrome (HPS) is a rare and potentially life-threatening blood disorder of the immune system. It mostly affects infants and children but can develop at any age.

• A to Z: Neoplasm (Tumor), Malignant

  Learn about tumors and cancer.

• A to Z: Neutropenia

  Neutropenia is when the body has very low levels of certain white blood cells called neutrophils, the body's main defense against infection.

• A to Z: Primitive Neuroectodermal Tumor (PNET)

  Primitive neuroectodermal tumors, or PNETs, are tumors that can happen anywhere in the brain or spine.

• A to Z: Kyphosis, Congenital

  Learn more about congenital kyphosis, an abnormal rounding of the spine that develops before birth.

• A to Z: Kyphosis, Postural

  Learn more about postural kyphosis, an abnormal rounding of the spine caused by irregular development of bones and muscles, sometimes due to slouching or poor posture.

• A to Z: Kyphosis, Scheuermann’s

  Learn more about Scheuermann's kyphosis, an abnormal rounding of the spine that can run in families and is usually seen in teens.

• A to Z: Lateral Malleolar Fracture

  See: Fracture, Lateral Malleolus.

• A to Z: Legg-Calvé-Perthes Disease

  Learn about this rare hip disorder, which is most common in boys.

• A to Z: Lumbago

  Learn about causes of back pain and conditions that affect the back and spine.

• A to Z: Medial Collateral Ligament (MCL) Injuries

  Learn more about MCL injuries and how they're treated.

• A to Z: Nursemaid’s Elbow (Annular Ligament Displacement)

  Nursemaid's elbow is a common injury in young kids that happens when a ligament slips out of place near the elbow.

• A to Z: Ollier Disease

  See: Chondrodystrophy.

• A to Z: Osteochondritis Dissecans

  Learn about osteochondritis dissecans, a joint condition in which a piece of bone and cartilage become unattached, either partially or completely.

• A to Z: Osteodystrophy

  Learn about complications of kidney and liver disease and conditions that affect bone development.

• A to Z: Osteogenesis Imperfecta

  Learn more about congenital disorders and bone deformities.

• A to Z: Osteoporosis

  Mostly affecting older people, osteoporosis is a disease that weakens the bones, causing them to become brittle and easily fractured.

• A to Z: Osteoporosis, Disuse

  Disuse osteoporosis is bone loss that results from not enough stress or pressure on the bones, making them brittle and weak, and easy to fracture.

• A to Z: Patellar Dislocation

  Patellar dislocation happens when the patella (kneecap) slips out of its normal position.

• A to Z: Pectus Carinatum

  Learn more about pectus carinatum, commonly called pigeon chest.

• A to Z: Pectus Excavatum

  Learn more about pectus excavatum, commonly called sunken chest.

• A to Z: Pott’s Fracture

  Bimalleolar fracture, Pott's fracture, medial malleolus, lateral malleolus, ankle, ankle fracture, broken ankle, tibia, fibula, shinbone, operative fixation, surgery, malleoli

• A to Z: Scoliosis

  Learn about scoliosis, an abnormal curvature in the spine often detected just before puberty begins.

• A to Z: Sever Disease

  Sever disease is a painful bone disorder due to inflammation (swelling) of the growth plate in the heel.

• A to Z: Slipped Capital Femoral Epiphysis (SCFE)

  In slipped capital femoral epiphysis (SCFE), the very top of the thighbone (called the femoral head) slips out of line with the rest of the thighbone, causing a weakened hip joint.

• A to Z: Slipped Disc

  Activities and sports that put stress on the back can lead to a slipped disc, which can cause pain in the back, arms, and legs.

• A to Z: Dislocation, Shoulder

  A shoulder dislocation causes the top of the upper arm bone (humerus) to slip out of its normal position in the shoulder socket.

• A to Z: Dislocation, Thumb

  A dislocation is when the bones in a joint slip out of their normal position. A dislocated thumb may happen from a fall, blow, or sports injury, especially if the thumb is bent back or jammed.

• A to Z: Dislocation, Toe

  A dislocation is when the bones in a joint slip out of their normal position. A dislocated toe may happen from a blow or jamming the toe, such as bumping the toe into furniture or during sports.

• A to Z: Disuse Osteoporosis

  See: Osteoporosis, Disuse.

• A to Z: Enchondromatosis

  See: Chondrodystrophy.

• A to Z: Enthesopathy

  Learn about rheumatic disorders and conditions that affect the joints and entheses.

• A to Z: Fracture, Bimalleolar

  Learn about types of lower extremity fractures and conditions that can affect the ankle and lower leg.

• A to Z: Fracture, Clavicle

  A clavicle fracture, or broken collarbone, is one of the most common broken bones among kids and teens.

• A to Z: Fracture, Collarbone

  A fall onto the shoulder or an outstretched arm can result in this type of broken bone. Learn more here.

• A to Z: Fracture, Distal Radius and Ulna

  Fractures of the distal radius and ulna, or broken bones of the forearm, are common childhood injuries.

• A to Z: Fracture, Elbow

  Fractured (broken) elbows are a common injury in kids and teens.

• A to Z: Fracture, Fibula

  A fractured fibula is a break to the smaller of the two bones in the lower leg.

• A to Z: Fracture, Lateral Malleolus

  Learn about types of lower extremity fractures and conditions that can affect the ankle and lower leg.

• A to Z: Fracture, Radius

  A fractured radius is a broken bone in the lower arm. It is a common injury that usually heals quickly.

• A to Z: Fracture, Scaphoid (Wrist)

  A fractured scaphoid is a broken small bone in the wrist.

• A to Z: Gait Abnormality (Abnormality of Gait)

  Learn about abnormality of gait (or gait abnormality), an unusual walking pattern or style.

• A to Z: Genu Valgum

  Learn about common childhood orthopedic conditions and conditions that affect the legs and knees.

• A to Z: Genu Varum

  Learn about common childhood orthopedic conditions and conditions that affect the legs and knees.

• A to Z: Joint Effusion

  Learn more about this type of joint swelling that can caused by infections, injuries, and arthritis.

• A to Z: Kyphosis

  Learn more about kyphosis, an abnormal rounding of the spine.

• A to Z: Hypoxemia

  Hypoxemia is a condition in which there is a lower than normal level of oxygen in the blood.

• A to Z: Pneumonia, Mycoplasma

  Mycoplasma pneumonia, also called walking pneumonia or atypical pneumonia, is a mild lung infection caused by bacteria.

• A to Z: Pneumonia, Viral

  Learn about viral pneumonia, a lung infection caused by a virus.

• A to Z: Pneumonitis

  Pneumonitis is a general term for inflammation of the lungs.

• A to Z: Respiratory Failure

  Learn what happens when the lungs cannot properly bring oxygen into or remove carbon dioxide from the blood.

• A to Z: Respiratory Syncytial Virus

  Learn about RSV, a contagious infection that's a major cause of respiratory illness in young children.

• A to Z: Sarcoidosis

  Learn about abnormal immune system responses and disorders that can affect the lungs, lymph system, and other organs.

• A to Z: Abnormality of Gait (Gait Abnormality)

  Abnormality of gait (or gait abnormality) is an unusual walking pattern or style.

• A to Z: Achondroplasia

  Achondroplasia is a genetic disorder that interferes with bone growth and causes dwarfism (short stature).

• A to Z: Anterior Cruciate Ligament (ACL) Injuries

  Learn more about ACL injuries and how they're treated.

• A to Z: Arthrogryposis

  Learn about congenital conditions and conditions that affect the muscles and joints in newborn babies.

• A to Z: Benign Joint Hypermobility Syndrome

  Learn about inherited disorders and conditions that can affect the joints and connective tissues.

• A to Z: Biceps Tendonitis

  Learn more about biceps tendonitis and how it's treated.

• A to Z: Calcaneal Apophysitis

  See: Sever Disease.

• A to Z: Cervicalgia

  Learn about causes of neck pain and conditions that can affect the cervical spine.