Diagnosis

The doctor will perform a physical exam and ask questions about your child's medical history, family history of high blood pressure, and nutrition and activity level.

Your child's blood pressure will be measured. The correct blood pressure cuff size is important for measuring accurately. It is also important that blood pressure be measured with proper technique, in a quiet environment, with the child resting comfortably. During a single visit, your child's blood pressure might be measured two or more times for accuracy.

For a diagnosis of high blood pressure, your child's blood pressure must be higher than normal when measured during at least three visits to the doctor.

If your child is diagnosed with high blood pressure, it's important to determine whether it's primary or secondary. These tests might be used to look for another condition that could be causing your child's high blood pressure:

• Blood tests to check your child's kidney function, electrolytes, and cholesterol and triglyceride levels (lipids)
• Urine sample test (urinalysis)
• Echocardiogram to create pictures of the heart and blood flow through the heart
• Ultrasound of your child's kidneys (renal ultrasound)

Ambulatory monitoring

To confirm a diagnosis of high blood pressure, your child's doctor might recommend ambulatory monitoring. This involves your child temporarily wearing a device that measures blood pressure throughout the day, including during sleep and various activities.

Ambulatory monitoring can help rule out blood pressure that's temporarily raised because your child is nervous at the doctor's office (white-coat hypertension).