3-hydroxy-3-methylglutaric aciduria (HMG)


3-hydroxy-3-methylglutaric aciduria (HMG) is an inborn error of metabolism, an inherited condition in which an enzyme, 3-hydroxy-3-methylglutaryl-CoA lyase, in the body is either missing or not working well. When this enzyme is not working well the body is unable to help break down the amino acid (a part of protein) known as leucine, and is also unable to properly make ketones, (substances that help the body store energy). HMG lyase deficiency is an organic acid condition because it can lead to the build-up of harmful organic acids and toxins in the body. Symptoms can vary and may include low muscle tone (hypotonia), vomiting, extreme tiredness/lethargy, enlarged liver, low blood sugar (hypoglycemia), and/or other potential signs and symptoms. HMG lyase deficiency can be a life-threatening condition. Illnesses or infections, going too long without food, or eating large amounts of protein are some examples of circumstances that could also trigger symptoms of HMG lyase deficiency. Management often includes a special diet, medication/supplements, other special precautions and emergency management recommendations. Support groups are available to help connect families living with HMG lyase deficiency with others who have experience or expertise with this condition.

To learn more about 3-hydroxy-3-methylglutaric aciduria, visit Screening, Technology, and Research in Genetics (STAR-G): 3-hydroxy-3-methylglutaryl-CoA lyase deficiency. Please see Medically Prescribed Formula for information about medically prescribed formula and pharmacologic interventions for inborn errors of metabolism. A listing of contact information for Minnesota inborn errors of metabolism medical specialty providers/clinics serving children affected with or undergoing evaluation for conditions that can be detected through Minnesota Newborn Screening is available upon request.