A to Z of Juvenile Idiopathic Arthritis


  • Ankylosing Spondylitis (AS): Inflammation and stiffening of the joints of the spine. It is also known as AS.
  • Antibody: A special protein produced by the body’s immune system that recognizes and helps fight infectious agents and other foreign substances that invade the body.
  • Anti-inflammatory: Something that reduces swelling, heat and pain. It is usually a medicine
  • Anti-nuclear antibody (ANA): This test is used to do two things: it helps identify the type of arthritis your child has; and, it is an important indicator of your child’s risk of developing eye problems.
  • Arthritis: A problem with the joints that causes swelling, pain, heat and a sense of stiffness.
  • Aspiration of a joint: This is where the fluid from a swollen joint is removed to be tested in a laboratory, to check for a possible infection.
  • Auto-immune disease: A disease of the immune system that makes it attacks your own body. Rheumatoid arthritis is an auto-immune disease.


  • Biologic medications: Specialist treatment for certain kinds of arthritis.
  • Biological therapies (biologics): This medication is used to control pain, swelling and stiffness when DMARDS are not effective to control. Etanercept, Adalimumab and Tocilizumab are funded for JIA in New Zealand. They suppress the immune system so your child may be more likely to catch infections and should not be given live vaccinations while taking biologics.
  • Bone scan: This uses a small amount of radiation to highlight the bones in a scanner.


  • Cartilage: A connective tissue that covers the ends of the bone in a joint.
  • Chronic: Does not go away. Long term.
  • Chronic recurrent multifocal osteomyelitis (CRMO): This is a disorder that causes bone pain due to inflammation in the bone not caused by infection. One or multiple bones can be affected.
  • Connective tissue disease: A general term for rare diseases such as lupus (Systemic Lupus Erythematosus), scleroderma, muscle inflammation and Sjogrens syndrome.
  • Consultant: A senior doctor who specialises in an area of medicine or surgery.
  • Corticosteroid: These are hormones that are produced naturally by the adrenal glands. As a medicine, they can rapidly reduce pain and inflammation. It reduces the activity of the immune system. It is also known as a steroid. They are most commonly given by injection into the inflamed joints.
  • C-reactive protein (CRP): This is a blood test that detects inflammation. Protein shows up when inflammation is found in the body. ESR and CRP show similar amounts of inflammation. But one may be high when the other is not. This test may be repeated to check a child’s response to medicine.
  • CT scan. This uses a series of X-rays and a computer to make detailed images of bones, muscles, fat, and organs. CT scans are more detailed than regular X-rays.


  • Disease-modifying anti-rheumatic drugs (DMARDS): A DMARDS drug such as methotrexate and sulfasalazine can slow the progression of JIA by ‘calming’ the overactive immune system. They take several months to reach maximum effectiveness.


  • Enthesitis-related arthritis (ERA): Also known as Spondyloarthritis. Affects where the muscles, ligaments or tendons attach to the bone (entheses). It most commonly affects the spine, heels, hips, knees, ankles and feet, but may also affect the fingers, elbows, pelvis, chest, digestive tract (Crohn’s disease or ulcerative colitis) and lower back (ankylosing spondylitis). More common in boys; typically appears in children between the ages of eight and 15.
  • Erythrocyte sedimentation rate (ESR or sed rate). This is a blood test that looks at how quickly red blood cells fall to the bottom of a test tube. When swelling and inflammation are present, the blood’s proteins clump together and become heavier than normal. They fall and settle faster at the bottom of the test tube. The faster the blood cells fall, the more severe the inflammation there is in the body.
  • Eye drops: These will be used if you have eye inflammation. They’re used to reduce the inflammation, prevent the swollen iris from sticking to the lens and to reduce pressure inside the eye. Some of the medicines used for the arthritis, such as methotrexate and the biological therapies, can be used to treat eye inflammation if the eye drops alone aren’t enough.


  • Flare: A period of time when symptoms of a disease are worse, it may last days, weeks or months.
  • Full blood count (FBC): A blood test to check for anything abnormal that might be important in managing the illness


  • Haematocrit: This blood test measures the number of red blood cells in a blood sample. Low levels of red blood cells (anaemia) are common in people with inflammatory arthritis and rheumatic diseases.
  • Henoch-Schonlein purpura (HSP): A form of vasculitis, a condition which involves inflammation of the blood vessels.  The most common vasculitis in children along with Kawasaki disease.
  • HLA-B27: A blood test that helps determine the type of arthritis your child may have.
  • Hydrotherapy: The use of water to soothe pain and improve mobility.


  • Immune system: The part of your body that fights against germs.
  • Inflammation: Swelling, redness, heat and pain. This happens when parts of your body are hurt or react to illness. The body sends extra blood cells to the place that is hurt.
  • Infusion: A way to give fluids or medicine directly into a vein.
  • Injection: To give medicine by needle under the skin, into a muscle or into a joint.
  • Immunosuppressant: These medicines suppress (limit) the activity of the body’s immune system.


  • Joint: Where two bones meet.


  • Juvenile idiopathic arthritis (JIA): The word ‘Juvenile’ means that young people / child. (16 years old or younger get this type of arthritis). The word ‘idiopathic’ means that we don’t know what the cause is. ‘Arthritis’ means inflammation of joints; it causes joint swelling, stiffness and pain. JIA is a chronic condition. Researchers aren’t sure why kids develop JIA. They believe kids with JIA have certain genes that are activated by a virus, bacteria or other external factors.
  • Juvenile dermatomyositis (JDM): This is a disease in children that causes skin rash (dermato) and muscle inflammation (myositis). It results in weak muscles.


  • Kawasaki disease: (also called mucocutaneous lymph node syndrome) This is the most common form of vasculitis that affects children, along with HSP (Henoch-Schonlein purpura), that commonly affects children. This disease produces irritation and inflammation of many tissues of the body, including the hands, feet, whites of the eyes, mouth, lips and throat.


  • Ligament: A strong white, shiny, flexible band of fibrous tissue that holds a joint together. Ligaments bind bone to bone.
  • Long-term: A long time, more than just weeks or months.
  • Lumbar: Refers to the part of the back between the ribs and the hips.
  • Lupus: A chronic disease where the skin, joints and internal organs can become inflamed. It is also known as Systemic Lupus Erythematosus (SLE).


  • Magnetic Resonance Imaging or Computed Tomography (MRI or CT scans): They do much the same as x-ray but in greater detail. They can also show changes in non-bone structures around the joints (like ligaments and tendons). This test uses large magnets and a computer to make detailed pictures of organs and structures in the body.
  • Mobility: Able to move around.
  • Musculoskeletal: Relating to or involving the muscles or skeleton (bones). Osteoarthritis, rheumatoid arthritis and back ache are examples of musculoskeletal diseases.
  • Myositis: Inflammation of the muscles, which can lead to muscle weakness.


  • Non-steroidal anti-inflammatory drugs (NSAIDS): This is a medicine that reduces inflammation and control stiffness and swelling, but they do not cure JIA. The most common side effects are stomach upsets.


  • Occupational Therapist (OT): A professional who helps people who are ill or injured learn better ways to do everyday activities, theyprovide other aids to help a child with everyday activities such as getting dressed or writing.
  • Oligoarthritis:(from ‘oligo’ meaning few). This occurs when up to four joints are affected, usually the knees and ankles. Children may also develop eye inflammation (iritis or uveitis).
  • Ophthalmologist: A doctor who specialises in eye problems.
  • Oral: Relating to the mouth or to take by mouth.
  • Orthopaedic surgeon: A doctor who operates on bones and joints.
  • Orthotic: The design and use of external appliances to support specific muscles promote a specific motion or correct deformities.
  • Outpatient: A person who is treated by hospital staff in a day clinic.


  • Paediatrician: Specialist doctor working with children.
  • Pain relievers (analgesics): This medication includes paracetamol; (Panadol) this medication can help your child feel more comfortable, be more active and sleep better but they do not reduce inflammation.
  • Patella: The medical term for the kneecap.
  • Pharmacist: A trained person who prepares medicine. This person makes sure you get the right kind and amount of medicine that your doctor prescribes.
  • Physical activity: This is essential for good health and wellbeing in children with JIA. Exercise helps reduce the pain of JIA, keeps muscles and bones strong, and improves confidence. You will need to find physical activities and sports that your child enjoys but that do not cause too much discomfort. Your child’s physiotherapist can advise on suitable activities and exercises. Swimming is great as it allows freedom of movement, cycling and yoga are also great activities, plus they are fun.
  • Physiotherapist: A trained professional who helps patients learn ways to reduce their pain. Also known as a physio. A physio helps patients increase and maintain their movement and muscle strength.
  • Platelet: Cells in the blood that help stop bleeding.
  • Podiatrist: Is a health professional specialising in diagnosis/treatment of disorders of the feet.
  • Polymyalgia Rheumatica (PMR): A disorder of the muscles and joints involving symptoms such as pain and stiffness, which involves the shoulders, arms, neck and hips and affects both sides of the body.
  • Polyarticular: (from ‘poly’ meaning many) This type involves five or more joints, with the same joints on each side of the body affected, including fingers, toes, wrists, ankles, hips, knees, neck and jaw.
  • Posture: The way in which somebody holds their body, especially when
  • Prescription: Written directions from your doctor to the pharmacist about your medicine. Also known as a ‘script’.
  • Prognosis: Prediction of the probable outcome of a disease based on the condition of the person, and the usual course of the disease in similar situations.
  • Psoriasis: A dry scaly skin rash.
  • Psoriatic arthritis (PsA): Joint symptoms and a scaly rash behind the ears and/or on the eyelids, elbows, knees, belly button and scalp, it may also affect the nails. Skin symptoms may occur before or after joint symptoms appear. May affect one or more joints, often the wrists, knees, ankles, fingers or toes.


  • Radiologist: A doctor who looks at and studies x-rays and other images to diagnose health problems.
  • Reactive arthritis: A type of arthritis that causes pain and swelling in the joints because of an infection elsewhere in the body.
  • Rehabilitation: Restoring skills by a person who has suffered an illness or injury so they can do as much as possible for themselves again.
  • Remission: A period of time when a disease shows no symptoms or signs.
  • Rheumatoid arthritis: A disease that causes inflammation in many joints.
  • Rheumatologist: A specialist Doctor who treats conditions involving the musculoskeletal system. The musculoskeletal system is made up of bones, muscles, tendons, ligaments, joints, cartilage, and other connective tissue. Rheumatologists medically treat diseases, disorders, etc., that affect the musculoskeletal system including many autoimmune diseases like JIA.
  • Rheumatoid factor (RF): An antibody detected by blood test. Proteins are produced by the immune system that can attack healthy tissue in the body.


  • Scleroderma: Chronic hardening and tightening of the skin and connective tissues. Loss of the skin’s ability to stretch. There can be a decreased hand function because of skin tightening on the hand and fingers.
  • Scoliosis: A condition that causes the spine to curve to the side.
  • Soft tissue: The ligaments, tendons, and muscles in the body.
  • Synovium: The membrane lining the inside of joints. Produces synovial fluid.
  • Systemic: In all parts of the body.
  • Systemic Lupus Erythematosus (SLE): A chronic disease where the skin, joints and internal organs can become inflamed. It is also known as Lupus.
  • Systemic onset JIA:Affects the entire body, (joints, skin and internal organs). This usually includes fevers and rashes, and may cause inflammation of the internal organs. Symptoms may be confused with other childhood diseases such as measles or glandular fever.


  • Tendons: The tough cords of tissue that connect muscles to bones.
  • TENS: Transcutaneous electrical nerve stimulation. A device which uses small pulses of electricity to relieve pain.
  • Therapy: Action to help a disease, illness or injury.
  • Treatment: The action or medicine used to take care of a disease or injury.


  • Ultrasound: A type of scan used to examine muscles, tendons, and internal organs.
  • Undifferentiated arthritis: This is arthritis that has symptoms of 2 or more JIA types above. Or the symptoms might not match any type of JIA.
  • Urine: A liquid waste made in the kidneys.
  • Uveitis: A condition that causes the middle layer of the eye to become inflamed. The eye examination usually involves the following:-

Assessment of vision: (with your glasses if you normally wear them), and the response of your pupils to light.

Tonometry: A tonometry exam measures the pressure inside your eye (intraocular pressure). Numbing eye drops may be used for this test.

A slit-lamp examination: A slit lamp is a microscope that magnifies and illuminates the front of your eye with an intense line of light. This evaluation is necessary to identify microscopic inflammatory cells in the front of the eye.

Ophthalmoscopy: Also known as funduscopy, this exam involves widening (dilating) the pupil with eye drops, and shining a bright light into the eye to examine the back of the eye.


  • Vasculitis: Inflamed blood vessels.


  • White blood cell count: This blood test measures the number of white blood cells in the blood. Higher levels of white blood cells may mean an infection. Lower levels may be a sign of some rheumatic diseases or a reaction to medicine.


  • X-ray: Takes pictures of your child’s joints to see how they change with time.