GLUTARIC ACIDEMIA (GA)

GA Full Form: Glutaric Acidemia/Aciduria

Prevalence of GA-1 in India: Glutaric acidemia type I occurs in approximately 1 of every 30,000 to 40,000 individuals. It is much more common in the Amish community and in the Ojibwa population of Canada, where up to 1 in 300 newborns may be affected. In India, the prevalence of IEM is one in 2497 newborns. With increasing awareness of newborn screening in India, detection of GA has strengthened.

Glutaric Aciduria Definition:

GA patients have inadequate levels of an enzyme that helps break down the amino acids lysine, hydroxylysine, and tryptophan, which are building blocks of protein. Excessive levels of these amino acids and their intermediate breakdown products can accumulate in the blood (acidemia) and in the urine (aciduria) leading to Glutaric aciduria or GA.

Glutaric Aciduria Causes:

Glutaric Aciduria Type-I is a rare hereditary metabolic disorder, caused by a deficiency of the enzyme glutaryl-CoA dehydrogenase. One of a group of disorders known as “organic acidemias.” Accumulation of 5- carbon dicarboxylic acids may impair synthesis of gamma-aminobutyric acid (GABA), which functions as a neurotransmitter in the brain, inhibiting nerve excitation. The gene associated with Glutaric Aciduria I has been mapped to chromosome 19.

Glutaric Aciduria Symptoms:

Babies with Glutaric Aciduria Type- I usually appear normal at birth. At almost any time during the first year of life, usually due to an acute illness, there may occur a crisis involving decreased muscle tone (hypotonia), vomiting, and high levels of organic acids in the blood, and central nervous system degeneration.

Glutaric Aciduria Test:

A positive MS/MS screening result should be confirmed by one or more alternative techniques, including a sensitive method for quantitative determination of GA and 3-OH-GA in urine or blood such as GC/MS, mutation analysis of the GCDH gene, and/or GCDH enzyme analysis. A normal urine or blood 3-OH-GA level will make the diagnosis unlikely, whereas an elevated urine or blood level of 3-OH-GA should be followed by mutation analysis and start of treatment.

TMS being the primary test should always be backed with a GC-MS (Gas chromatography mass spectrometry) test to reconfirm the diagnosis. GC-MS is gold standard technology for confirming Glutaric Acidemia.

 

Glutaric Aciduria Treatment:

Elevated concentrations of glutaric acid, beta-hydroxy-glutaric acid and occasionally glutaconic acid appear in the urine of children with GA. Excretion of glutaric acid in the urine may exceed 1 gram per day, an excessive amount. Glutaric acid concentrations are also elevated in blood serum, cerebrospinal fluid, and body tissues. Hence, nutrition management plays a very crucial role.

Glutaric Aciduria dietary management includes:-

Low protein diet with lysine free, low tryptophan and micronutrient supplements. Regular monitoring of plasma amino acids, specifically lysine and arginine, is very important. Carnitine supplementation of 100mg/kg/day is also given to promote growth & development.

Overall, Nutrition management of GA-1 consists of restricting lysine and tryptophan, supplementing L-carnitine, and providing sufficient energy to prevent catabolism.

GA Diet in India:

GA patients must remain on a protein-restrictive diet that limits the amount of lysine and tryptophan they take in. Protein-restriction must start as soon as possible, after birth to promote proper growth and development. Amino acid based specialized nutrition formulae are available that provide all the nutrients necessary for proper growth and development, but lack lysine and tryptophan. Hence, GA patients require special diets. Pristine Organics offers lysine and tryptophan free diets at 15% and 48% Protein levels depending on the patients’ needs in India. The optimum amount of Pristine Balance Metanutrition GA diet is calculated based on the child’s age and body weight and is constantly adapted to his or her needs.

Providing education and support for the family is the key to a successful long range of therapy. Effective treatment is best achieved by a team of specialists such as your Physician, Nutritionist, Geneticist, Neurologist, and Psychologist.

A healthy Glutaric Acidemia disorder life expectancy can be foreseen with a wholesome approach with watchful diet, medical support and optimal nutrient supplement.