Organic Acidaemias


3-Methylcrotonyl CoA Carboxylase Deficiency (3MCC)



3-methylcrotonyl-CoA carboxylase deficiency (3-MCC) is an inherited autosomal recessive disorder where the body is unable to process certain parts of proteins properly. 3-MCC is an organic acid condition because it can lead to harmful amounts of organic acids and toxins in the body.


The condition is diagnosed during newborn screening via the heel prick test taken 48-72 hours after birth.


1:50,000 estimated worldwide.


Treatment largely involves restricting protein intake to prevent the build-up of 3-hydroxyisovaleric acid and 3 methylcoronlglycine. Many 3-MCC individuals also require supplements of carnitine.

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Organic Acidurias Handbook

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