UPDATE OF FOLLOW UP OF 29 CHILDREN WITH ORGANIC ACIDURIAS FROM CHILE

Abstract
Propionic aciduria (PA) and Methylmalonic aciduria (MMA) result from an inherited abnormality of the enzymes propionyl CoA carboxylase and methylmalonyl CoA mutase respectively. This produces an imbalance of the amino acids: methionine, threonine, valine and isoleucine (MTVI). Their clinical presentation can be neonatal or late onset forms. Twenty nine cases of organic acidurias have been diagnosed (21 PA and 8 MMA). The average age of diagnosis was 6.6 days for the neonatal form and 13.0 months for the late onset form. The most frequent symptoms were hypotonia, lethargy and ketosis. The neonatal PA and MMA had average ammonia of 1 137 ± 882 μg/dl and of 1 500 ± 801.9 μg/dl respectively. Nine children were dialysed, 37.9% have died. At this moment, 18 children are in follow up with ages ranging between 2.4 and 19.5 years. The children with neonatal and late onset forms had average propionylcarnitines of 42.8 ± 25 μM/l and 37.3 ± 21.7 and free carnitine of 49 ± 6.5 and 52.3 ± 3.5 μM/l respectively. According to the body mass index, 22% is underweight, 50% is normal, 22% is overweight and 1 child is obese. The average intellectual quotient in the neonatal onset form is 58.4 ± 13 and in the late onset form is 73.6 ± 15. It is concluded that the prognosis depends closely to the presentation form and to a frequent and strict follow-up.

Key words
Organic acidemia, methylmalonic acidemia, propionic acidemia, acylcarnitines, intellectual quotient

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