Because there are many forms of chILD, there is not one specific test that is used for diagnosis. Before giving a diagnosis of chILD, doctors should rule out other possible causes of the symptoms. Such conditions include: Cystic fibrosis, Asthma, Acid reflux, Cardiac (heart) disease, Aspiration, Scoliosis, Chest wall abnormalities, Neuro-muscular disease, and Immune deficiency.
Common tests in the diagnostic process include:
- Imaging Studies
- Chest x-rays and High-Resolution Computed Tomography (HRCT) to get images of the lungs
- Barium Swallow to look for signs of aspiration while swallowing food and liquids of different consistencies
- Echocardiography to look at the function of the heart
- Blood Gases to measure the levels of oxygen and carbon dioxide in the blood
- Pulse Oximetry to estimate how well the hemoglobin is carrying oxygen
- Sweat Testing which is a common test for cystic fibrosis
- Skin Testing for tuberculosis
Other Laboratory Tests are often performed to help with the diagnosis and to test the extent of the lung disease. These can include:
- Bronchoscopy with bronchoalveolar lavage (BAL)
- Electrocardiogram and/or Cardiac Catheterization to check for heart defects or Pulmonary Hypertension
- pH Probe to look for acid reflux
- Exercise Testing
- Genetic Tests
Only a few of the chILD diseases have known genetic causes. Tests on blood and other tissue to find known gene disorders, see if someone carries a gene for a disease, or confirm a diagnosis when symptoms are present
- Pulmonary Function Tests (PFTs)
There are many types of tests. Before the age of 3, some centers can do infant PFTs. These require sedation and are only done in certain centers. By 3 to 6 years old, many kids can do regular PFTs which do not require sedation, are available at most centers, and can be very useful to monitor lung function. PFTs measure how well the lungs work. These involve a series of breathing moves to test how much air the lungs take in and push out and how fast they can do it. If a child has a lung problem, PFTs can show what type and how severe it is.
- Lung Biopsy
Right now, this is the “gold standard” test used to diagnose and type many forms of chILD. An experienced pathologist can learn a lot about the health of the lung tissue and identify many of the chILD disorders from the lung biopsy. However, a biopsy does not yield a diagnosis 100 percent of the time! The location of the biopsy, proper handling of the sample, and the experience of the pathologist are all vital to a successful biopsy. We recommend that you have biopsies performed at experienced chILD centers whenever possible.