Diagnosis
The diagnosis of Down syndrome usually considers the characteristics listed in the signs and symptoms section. This syndrome is usually detected early in the course of pregnancy in women who screen correctly, especially in high-risk pregnancies.
When they are taken to the doctor, he would be interested to know a few facts to guide the diagnosis:
- In most cases, the parents come to the doctor’s office with concerns about developmental delay, visual or hearing problems, and recurrent respiratory infections
- Doctors will ask if the patient is vomiting or feeding adequately because some of them develop a blockage in the gastrointestinal tract
- The delay in cognitive abilities is fundamental for the diagnosis
- Doctors will also highlight the importance of cardiovascular health, especially palpitations, fainting, arrhythmia, etc.
- Sleeping problems, sleep apnea, daytime drowsiness, and difficulty waking are also crucial for the diagnosis of this condition.
- In some cases, Down syndrome patients can be subject to sexual abuse, and doctors may need to perform a complete physical exam to rule this out.
In most cases, the diagnosis is not a problem, and it is not always necessary to perform a DNA test. However, doctors may need to know about the type of trisomy (full trisomy, translocation, or mosaicism), which is why they usually order a DNA test. In some cases, it will be recommended to differentiate Down syndrome with a trisomy 18, which has similar features. In that scenario, it is also recommended a DNA test.