3-hydroxy-3-methylglutaric aciduria (HMG)
Diagnosis and Testing
How do I get tested for 3-Hydroxy-3-Methylglutaric Aciduria (HMG)?
If the newborn screen comes back positive for 3-Hydroxy-3-methylglutaric aciduria, follow up testing would need to be completed for a positive diagnosis of 3-Hydroxy-3-methylglutaric aciduria. This involves testing the blood and urine of the patient to look for organic acid and amino acid levels. There is a specific pattern of these that would indicate a positive diagnosis of 3-Hydroxy-3-methylglutaric aciduria.
More Diagnosis and Testing Content
Is there newborn testing for 3-Hydroxy-3-Methylglutaric Aciduria (HMG)?
Yes, 3-Hydroxy-3-methylglutaric aciduria is included on newborn screening.
Is there more than one test for 3-Hydroxy-3-Methylglutaric Aciduria (HMG)?
For a positive diagnosis of 3-Hydroxy-3-methylglutaric aciduria (HMG), blood and urine from the patient needs to be tested for organic acid and amino acid levels. Genetic testing may then be completed to further confirm the diagnosis.
Who else in my family should be tested for 3-Hydroxy-3-methylglutaric aciduria (HMG)?
Most likely, if a family member has not shown symptoms of 3-Hydroxy-3-methylglutaric aciduria, then they do not have 3-Hydroxy-3-methylglutaric aciduria. Family members of an individual diagnosed with 3-Hydroxy-3-methylglutaric aciduria may a carrier. This means that they do not have the medical concerns associated with this condition, but have a chance of having children with 3-Hydroxy-3-methylglutaric aciduria. The risk to have a child with 3-Hydroxy-3-methylglutaric aciduria are dependent on if their partner(s) were also a carrier of the syndrome.
If the parents of an affected child have any siblings that are interested in having children, they may want to be tested to see if they are carriers. If they find that they are carriers, their partner may also want to be tested to determine their risk of having a child with 3-Hydroxy-3-methylglutaric aciduria.
Does it matter if you test blood vs. saliva vs biopsy for 3-Hydroxy-3-Methylglutaric Aciduria (HMG)?
Because different tissues will have different levels of organic and amino acids, it is important to test both urine and blood for a positive diagnosis of 3-Hydroxy-3-methylglutaric aciduria. Amnio acid and urine organic acid levels are not measured adequately in saliva tissue. Genetic testing is usually completed on a blood sample, however, DNA can also be isolated for testing from a saliva sample or skin biopsy.