How do you Diagnose DOOR Syndrome?
DOOR syndrome is diagnosed based on clinical symptoms, imaging (e.g. x-ray), genetic testing and a detailed family history.
When a baby is born, the physical abnormalities, such as shortened fingers and toes, or an extra bone in the thumb, should be taken as clinical indicators to test for hearing loss.
Specialized hearing tests help to confirm suspected deafness in the initial months of the baby’s life.
Genetic tests help to identify potential TBC1D24 mutations or variations. In DOOR syndrome, TBC1D24 variations are inherited in an autosomal recessive manner (where the child inherits a mutated version of TBC1D24 from each parent). The mutations in TBC1D24 give rise to varied clinical changes in the brain, bones, and ears. However, there are cases of DOOR syndrome where TBC1D24 is normal.
Elevated levels of 2-oxoglutaric acid are detected in the plasma (colorless portion of blood) and urine of those with DOOR syndrome. The reasons for this are unclear
The following investigations help to identify and confirm the diagnosis of DOOR.
- MRI helps to record cross-sectional pictures of the brain with the help of radio waves and magnetic field.
EEGis used to record irregular electrical activity in the brain.
- CT scan creates cross-sectional pictures of the brain with the help of x-rays, which is then displayed on the computer.
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