A Directory of Medical Tests





Taking a medical history and performing a physical examination
usually provide the information a doctor needs to evaluate a child's
health or to understand what's causing an illness. But sometimes,
doctors need to order tests to find out more.

Here are some common tests and what they involve:

Blood Tests


Blood tests usually can be done in a doctor's office or in a lab
where technicians are trained to take blood. When only a small amount of
blood is needed, the sample can sometimes be taken from a baby by
sticking a heel and from an older child by sticking a finger with a
small needle.

If a larger blood sample is needed, the technician drawing the blood
will clean the skin, insert a needle into a vein (usually in the arm or
hand), and withdraw blood. In kids, it sometimes takes more than one
try. A bandage and a cotton swab will help stop the flow of blood when
the needle is removed.

Blood tests can be scary for kids, so try to be a calming presence
during the procedure. Holding your child's hand or offering a stuffed
animal or other comforting object can help. Tell your child that it may
pinch a little, but that it will be over soon. With younger kids, try
singing a song, saying the alphabet, or counting together while the
blood is being drawn.

Common blood tests include:

• Complete blood count (CBC). A CBC
  measures the levels of different types of blood cells. By determining
  if there are too many or not enough of each blood cell type, a CBC can
  help to detect a wide variety of illnesses or signs of infection.
  
• Blood chemistry test. Basic blood chemistry tests
  measure the levels of certain electrolytes, such as sodium and
  potassium, in the blood. Doctors typically order them to look for any
  sign of kidney dysfunction, diabetes, metabolic disorders, and tissue
  damage.
  
• Blood culture. A blood culture
  may be ordered when a child has symptoms of an infection — such as a
  high fever or chills — and the doctor suspects bacteria may have spread
  into the blood. A blood culture shows what type of germ is causing an
  infection, which will determine how it should be treated.
  
• Lead test. The American Academy of Pediatrics (AAP) recommends that all toddlers get tested for lead in the blood at 1 and 2 years of age since young kids are at risk for lead poisoning
  if they eat or inhale particles of lead-based paint. High lead levels
  can cause stomach problems and headaches and also have been linked to
  some developmental problems.
  
• Liver function test. Liver function tests
  check to see how the liver is working and look for any sort of liver
  damage or inflammation. Doctors typically order one when looking for
  signs of a viral infection (like mononucleosis or viral hepatitis) or
  liver damage from other health problems.
  
• Pregnancy and Newborns Tests
  
  State requirements differ regarding tests for newborns and pregnant
  women, and recommendations by medical experts are often updated. So talk
  with the doctor if you have questions about what's right for you.
  
• Prenatal tests. From ultrasounds to amniocentesis, a wide array of prenatal tests
  can help keep pregnant women informed. These tests can help identify —
  and then treat — health problems that could endanger both mother and
  baby. Some tests are done routinely for all pregnancies. Others are done
  if the pregnancy is considered high-risk (e.g., when a woman is 35 or
  older, is younger than 15, is overweight or underweight, or has a
  history of pregnancy complications).
  
• Multiple marker test. Most pregnant women are offered a blood-screening test between weeks 15-20. Also known as a "triple marker" or quadruple screen, this blood test can reveal conditions like spina bifida or Down syndrome
  by measuring certain hormones and protein levels in the mother's blood.
  Keep in mind that these are screening tests and only show the
  possibility of a problem existing — they don't provide definitive
  diagnoses. However, if results show a potential problem, a doctor will
  recommend other diagnostic tests.
  
• Newborn screening tests. These tests
  are done soon after a child is born to detect conditions that often
  can't be found before delivery, like sickle cell anemia or cystic
  fibrosis. Blood is drawn (usually from a needle stick on the heel) and
  spots are placed on special paper, which is then sent to a lab for
  analysis. Different states test for different diseases in infants.
  
• Bilirubin level. Bilirubin is a substance in the blood that can build up in babies and cause their skin to appear jaundiced (yellow). Usually jaundice
  is a harmless condition, but if the level of bilirubin gets too high,
  it can lead to brain damage. A baby who appears jaundiced may have a
  bilirubin level check, which is done with an instrument placed on the
  skin or by blood tests.
  
• Hearing screen. The American Academy of Pediatrics (AAP) recommends that all babies have a hearing screen
  done before discharge from the hospital, and most states have universal
  screening programs. It's important to pick up hearing deficits early so
  that they can be treated as soon as possible. Hearing screens take 5-10
  minutes and are painless. Sometimes they involve putting small probes
  in the ears; other times, they're done with electrodes.
  
• Radiology Tests
  
• X-rays. X-rays can help doctors find a variety of
  conditions, including broken bones and lung infections. X-rays aren't
  painful, and typically involve just having the child stand, sit, or lie
  on a table while the X-ray machine takes a picture of the area the
  doctor is concerned about. The child is sometimes given a special gown
  or covering to help protect other areas of the body from radiation.
  
• Ultrasound. Though they're typically associated
  with pregnancy, doctors order ultrasounds in lots of different cases.
  For example, ultrasounds can be used to look for collections of fluid in
  the body, for problems with the kidneys, or to look at a baby's brain.
  An ultrasound is painless and uses high-frequency sound waves to bounce
  off organs and create a picture. A special jelly is applied to the skin,
  and a handheld device is moved over the skin. The sound waves that come
  back produce an image on a screen. The images seen on most ultrasounds
  are difficult for the untrained eye to decipher, so a doctor will view
  the image and interpret it.
  
• Computed tomography (CAT scan or CT-Scan). CAT
  scans are a kind of X-ray, and typically are ordered to look for things
  such as appendicitis, internal bleeding, or abnormal growths. A scan is
  not painful, but sometimes can be scary for young kids. A child is asked
  to lie on a narrow table, which slides into a scanner. A scan may
  require the use of a contrast material (a dye or other substance) to
  improve the visibility of certain tissues or blood vessels. The contrast
  material may be swallowed or given through an IV.
  
• Magnetic resonance imaging (MRI). MRIs
  use radio waves and magnetic fields to produce an image. MRIs are often
  used to look at bones, joints, and the brain. The child is asked to lie
  on a narrow table and it slides in to the middle of an MRI machine.
  While MRIs are not painful, they can be noisy and long, making them
  scary to kids. Often, children need to be sedated for MRIs. Contrast
  material is sometimes given through an IV in order to get a better
  picture of certain structures.
  
• Upper gastrointestinal imaging (Upper GI). An upper GI
  is a study that involves swallowing contrast material while X-rays are
  taken of the top part of the digestive system. This allows the doctor to
  see how a child swallows. Upper GI studies are used to evaluate things
  like difficulty swallowing and gastroesophageal reflux (GERD).
  An upper GI isn't painful, but some kids don't like to drink the
  contrast material, which sometimes can be flavored to make it more
  appealing.
  
• Voiding cystourethrogram (VCUG). A VCUG
  involves putting dye into the bladder and then watching with continuous
  X-rays to see where the dye goes. Doctors typically order a VCUG when
  they are concerned about urinary reflux, which can sometimes lead to
  kidney damage later. A catheter is inserted through the urethra, into
  the bladder, which can be uncomfortable and scary for a child, but
  usually is not painful. The bladder is then filled with contrast
  material that is put in through the catheter. Images are taken while the
  bladder is filling and then while the child is urinating, to see where
  the dye and the urine go.
  
• Other Tests
  
• Throat culture (strep screen). Doctors often order throat cultures to test for the germs that cause strep throat, which are known as group A streptococcus,
  or strep. The cultures are done in the doctor's office and aren't
  painful, but can be uncomfortable for a few seconds. The doctor or
  medical assistant wipes the back of the throat with a long cotton swab.
  This tickles the back of the throat and can cause a child to gag, but
  will be over very quickly, especially if your child stays still.
  
• Stool test. Stool (or feces or poop) can provide
  doctors with valuable information about what's wrong when your child has
  a problem in the stomach, intestines, or another part of the
  gastrointestinal system. The doctor may order stool tests
  if there is suspicion of something like an allergy, an infection, or
  digestive problems. Sometimes it is collected at home by a parent in a
  special container that the doctor provides. The doctor will also provide
  instructions on how to get the most useful sample for analysis.
  
• Urine test. Doctors order urine tests
  to make sure that the kidneys are functioning properly or when they
  suspect an infection in the kidneys or bladder. It can be taken in the
  doctor's office or at home. It's easy for toilet-trained kids to give a
  urine sample since they can go in a cup. In other cases, the doctor or
  nurse will insert a catheter (a narrow, soft tube) through the urinary
  tract opening into the bladder to get the urine sample. While this can
  be uncomfortable and scary for kids, it's typically not painful.
  
• Lumbar puncture (spinal tap). During a lumbar puncture
  a small amount of the fluid that surrounds the brain and spinal cord,
  the cerebrospinal fluid, is removed and examined. In kids, a lumbar
  puncture is often done to look for meningitis, an infection of the
  meninges (the membrane covering the brain and spinal cord). Other
  reasons to do lumbar punctures include: to remove fluid and relieve
  pressure with certain types of headaches, to look for other diseases in
  the central nervous system, or to place chemotherapy medications into
  the spinal fluid. Spinal taps, which can be done on an inpatient or
  outpatient basis, might be uncomfortable but shouldn't be too painful.
  Depending on a child's age, maturity, and size, the test may be done
  while the child is sedated.
  
• Electroencephalography (EEG). EEGs
  often are used to detect conditions that affect brain function, such as
  epilepsy, seizure disorders, and brain injury. Brain cells communicate
  by electrical impulses, and an EEG measures and records these impulses
  to detect anything abnormal. The procedure isn't painful but kids often
  don't like the electrodes being applied to their heads. A technician
  arranges several electrodes at specific sites on the head, fixing them
  in place with sticky paste. The patient must remain still and lie down
  while the EEG is done.
  
• Electrocardiography (EKG). EKGs
  measure the heart's electrical activity to help evaluate its function
  and identify any problems. The EKG can help determine the rate and
  rhythm of heartbeats, the size and position of the heart's chambers, and
  whether there is any damage present. EKGs can detect abnormal heart
  rhythms, some congenital heart defects, and heart tissue that isn't
  getting enough oxygen. It's not a painful procedure — the child must lie
  down and a series of small electrodes are fixed on the skin with sticky
  papers on the chest, wrists, and ankles. The patient must sit still and
  may be asked to hold his or her breath briefly while the heartbeats are
  recorded.
  
• Electromyography (EMG). An EMG
  measures the response of muscles and nerves to electrical activity.
  It's used to help determine muscle conditions that might be causing
  muscle weakness, including muscular dystrophy and nerve disorders. A
  needle electrode is inserted into the muscle (the insertion might feel
  similar to a pinch) and the signal from the muscle is transmitted from
  the electrode through a wire to a receiver/amplifier, which is connected
  to a device that displays a readout. EMGs can be uncomfortable and
  scary to kids, but aren't usually painful. Occasionally kids are sedated
  while they're done.
  
• Biopsies. Biopsies
  are samples of body tissues taken to look for things such as cancer,
  inflammation, celiac disease, or the presence or absence of certain
  cells. Biopsies can be taken from almost anywhere, including lymph
  nodes, bone marrow, or kidneys. Doctors examine the removed tissue under
  a microscope to make a diagnosis. Kids are usually sedated for a
  biopsy.