Testing & Diagnosis for Primary Immunodeficiency in Children


Many people (including some doctors) still mistakenly think that PIDDs are rare. For that reason, many people are diagnosed too late. The first step in treating your child is forming an accurate and complete diagnosis. To determine your child's primary immunodeficiency disorder, Children's doctors will use a combination of medical history, physical examination and laboratory tests.

Medical history

  • Since these disorders are genetic, it is also important for us to obtain a full medical history of both your child and your family.

Physical examination

  • This is important to look for signs of infection or other findings that can provide clues regarding specific PIDDs.


  • Blood tests we perform will help us determine which immune system components responsible for fighting off infection are affected, such as white blood cells or antibodies. The type of abnormality identified will help determine what type of PIDD your child has.
  • Other tests such as X-rays or CT scans may also be helpful to find infections or other clues regarding specific PIDDs.

Prenatal or newborn testing

  • For mothers who have already had a child with a PID, prenatal testing can be done for subsequent pregnancies. Samples of amniotic fluid, blood or cells from the placenta are tested for PIDD in order to be prepared to start treating a child with PIDD soon after birth.
  • Currently, Massachusetts is one of only a few states in the USA that conducts normal newborn screening for severe combined immunodeficiency (SCID).
    Read our FAQs to learn more about tests, treatment or procedures.
    After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child’s condition. Then we will meet with you and your family to discuss the results and outline the best treatment options.